org.apache.commons.lang.text.StrBuilder Maven / Gradle / Ivy
/*
* Licensed to the Apache Software Foundation (ASF) under one or more
* contributor license agreements. See the NOTICE file distributed with
* this work for additional information regarding copyright ownership.
* The ASF licenses this file to You under the Apache License, Version 2.0
* (the "License"); you may not use this file except in compliance with
* the License. You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/
package org.apache.commons.lang.text;
import java.io.Reader;
import java.io.Writer;
import java.util.Collection;
import java.util.Iterator;
import java.util.List;
import org.apache.commons.lang.ArrayUtils;
import org.apache.commons.lang.SystemUtils;
/**
* Builds a string from constituent parts providing a more flexible and powerful API
* than StringBuffer.
*
* The main differences from StringBuffer/StringBuilder are:
*
* - Not synchronized
* - Not final
* - Subclasses have direct access to character array
* - Additional methods
*
* - appendWithSeparators - adds an array of values, with a separator
* - appendPadding - adds a length padding characters
* - appendFixedLength - adds a fixed width field to the builder
* - toCharArray/getChars - simpler ways to get a range of the character array
* - delete - delete char or string
* - replace - search and replace for a char or string
* - leftString/rightString/midString - substring without exceptions
* - contains - whether the builder contains a char or string
* - size/clear/isEmpty - collections style API methods
*
*
*
* Views
*
* - asTokenizer - uses the internal buffer as the source of a StrTokenizer
* - asReader - uses the internal buffer as the source of a Reader
* - asWriter - allows a Writer to write directly to the internal buffer
*
*
*
*
* The aim has been to provide an API that mimics very closely what StringBuffer
* provides, but with additional methods. It should be noted that some edge cases,
* with invalid indices or null input, have been altered - see individual methods.
* The biggest of these changes is that by default, null will not output the text
* 'null'. This can be controlled by a property, {@link #setNullText(String)}.
*
* Prior to 3.0, this class implemented Cloneable but did not implement the
* clone method so could not be used. From 3.0 onwards it no longer implements
* the interface.
*
* @author Apache Software Foundation
* @since 2.2
* @version $Id: StrBuilder.java 1057349 2011-01-10 20:40:49Z niallp $
*/
public class StrBuilder implements Cloneable {
/**
* The extra capacity for new builders.
*/
static final int CAPACITY = 32;
/**
* Required for serialization support.
*
* @see java.io.Serializable
*/
private static final long serialVersionUID = 7628716375283629643L;
/** Internal data storage. */
protected char[] buffer; // TODO make private?
/** Current size of the buffer. */
protected int size; // TODO make private?
/** The new line. */
private String newLine;
/** The null text. */
private String nullText;
//-----------------------------------------------------------------------
/**
* Constructor that creates an empty builder initial capacity 32 characters.
*/
public StrBuilder() {
this(CAPACITY);
}
/**
* Constructor that creates an empty builder the specified initial capacity.
*
* @param initialCapacity the initial capacity, zero or less will be converted to 32
*/
public StrBuilder(int initialCapacity) {
super();
if (initialCapacity <= 0) {
initialCapacity = CAPACITY;
}
buffer = new char[initialCapacity];
}
/**
* Constructor that creates a builder from the string, allocating
* 32 extra characters for growth.
*
* @param str the string to copy, null treated as blank string
*/
public StrBuilder(String str) {
super();
if (str == null) {
buffer = new char[CAPACITY];
} else {
buffer = new char[str.length() + CAPACITY];
append(str);
}
}
//-----------------------------------------------------------------------
/**
* Gets the text to be appended when a new line is added.
*
* @return the new line text, null means use system default
*/
public String getNewLineText() {
return newLine;
}
/**
* Sets the text to be appended when a new line is added.
*
* @param newLine the new line text, null means use system default
* @return this, to enable chaining
*/
public StrBuilder setNewLineText(String newLine) {
this.newLine = newLine;
return this;
}
//-----------------------------------------------------------------------
/**
* Gets the text to be appended when null is added.
*
* @return the null text, null means no append
*/
public String getNullText() {
return nullText;
}
/**
* Sets the text to be appended when null is added.
*
* @param nullText the null text, null means no append
* @return this, to enable chaining
*/
public StrBuilder setNullText(String nullText) {
if (nullText != null && nullText.length() == 0) {
nullText = null;
}
this.nullText = nullText;
return this;
}
//-----------------------------------------------------------------------
/**
* Gets the length of the string builder.
*
* @return the length
*/
public int length() {
return size;
}
/**
* Updates the length of the builder by either dropping the last characters
* or adding filler of unicode zero.
*
* @param length the length to set to, must be zero or positive
* @return this, to enable chaining
* @throws IndexOutOfBoundsException if the length is negative
*/
public StrBuilder setLength(int length) {
if (length < 0) {
throw new StringIndexOutOfBoundsException(length);
}
if (length < size) {
size = length;
} else if (length > size) {
ensureCapacity(length);
int oldEnd = size;
int newEnd = length;
size = length;
for (int i = oldEnd; i < newEnd; i++) {
buffer[i] = '\0';
}
}
return this;
}
//-----------------------------------------------------------------------
/**
* Gets the current size of the internal character array buffer.
*
* @return the capacity
*/
public int capacity() {
return buffer.length;
}
/**
* Checks the capacity and ensures that it is at least the size specified.
*
* @param capacity the capacity to ensure
* @return this, to enable chaining
*/
public StrBuilder ensureCapacity(int capacity) {
if (capacity > buffer.length) {
char[] old = buffer;
buffer = new char[capacity * 2];
System.arraycopy(old, 0, buffer, 0, size);
}
return this;
}
/**
* Minimizes the capacity to the actual length of the string.
*
* @return this, to enable chaining
*/
public StrBuilder minimizeCapacity() {
if (buffer.length > length()) {
char[] old = buffer;
buffer = new char[length()];
System.arraycopy(old, 0, buffer, 0, size);
}
return this;
}
//-----------------------------------------------------------------------
/**
* Gets the length of the string builder.
*
* This method is the same as {@link #length()} and is provided to match the
* API of Collections.
*
* @return the length
*/
public int size() {
return size;
}
/**
* Checks is the string builder is empty (convenience Collections API style method).
*
* This method is the same as checking {@link #length()} and is provided to match the
* API of Collections.
*
* @return true if the size is 0.
*/
public boolean isEmpty() {
return size == 0;
}
/**
* Clears the string builder (convenience Collections API style method).
*
* This method does not reduce the size of the internal character buffer.
* To do that, call clear() followed by {@link #minimizeCapacity()}.
*
* This method is the same as {@link #setLength(int)} called with zero
* and is provided to match the API of Collections.
*
* @return this, to enable chaining
*/
public StrBuilder clear() {
size = 0;
return this;
}
//-----------------------------------------------------------------------
/**
* Gets the character at the specified index.
*
* @see #setCharAt(int, char)
* @see #deleteCharAt(int)
* @param index the index to retrieve, must be valid
* @return the character at the index
* @throws IndexOutOfBoundsException if the index is invalid
*/
public char charAt(int index) {
if (index < 0 || index >= length()) {
throw new StringIndexOutOfBoundsException(index);
}
return buffer[index];
}
/**
* Sets the character at the specified index.
*
* @see #charAt(int)
* @see #deleteCharAt(int)
* @param index the index to set
* @param ch the new character
* @return this, to enable chaining
* @throws IndexOutOfBoundsException if the index is invalid
*/
public StrBuilder setCharAt(int index, char ch) {
if (index < 0 || index >= length()) {
throw new StringIndexOutOfBoundsException(index);
}
buffer[index] = ch;
return this;
}
/**
* Deletes the character at the specified index.
*
* @see #charAt(int)
* @see #setCharAt(int, char)
* @param index the index to delete
* @return this, to enable chaining
* @throws IndexOutOfBoundsException if the index is invalid
*/
public StrBuilder deleteCharAt(int index) {
if (index < 0 || index >= size) {
throw new StringIndexOutOfBoundsException(index);
}
deleteImpl(index, index + 1, 1);
return this;
}
//-----------------------------------------------------------------------
/**
* Copies the builder's character array into a new character array.
*
* @return a new array that represents the contents of the builder
*/
public char[] toCharArray() {
if (size == 0) {
return ArrayUtils.EMPTY_CHAR_ARRAY;
}
char chars[] = new char[size];
System.arraycopy(buffer, 0, chars, 0, size);
return chars;
}
/**
* Copies part of the builder's character array into a new character array.
*
* @param startIndex the start index, inclusive, must be valid
* @param endIndex the end index, exclusive, must be valid except that
* if too large it is treated as end of string
* @return a new array that holds part of the contents of the builder
* @throws IndexOutOfBoundsException if startIndex is invalid,
* or if endIndex is invalid (but endIndex greater than size is valid)
*/
public char[] toCharArray(int startIndex, int endIndex) {
endIndex = validateRange(startIndex, endIndex);
int len = endIndex - startIndex;
if (len == 0) {
return ArrayUtils.EMPTY_CHAR_ARRAY;
}
char chars[] = new char[len];
System.arraycopy(buffer, startIndex, chars, 0, len);
return chars;
}
/**
* Copies the character array into the specified array.
*
* @param destination the destination array, null will cause an array to be created
* @return the input array, unless that was null or too small
*/
public char[] getChars(char[] destination) {
int len = length();
if (destination == null || destination.length < len) {
destination = new char[len];
}
System.arraycopy(buffer, 0, destination, 0, len);
return destination;
}
/**
* Copies the character array into the specified array.
*
* @param startIndex first index to copy, inclusive, must be valid
* @param endIndex last index, exclusive, must be valid
* @param destination the destination array, must not be null or too small
* @param destinationIndex the index to start copying in destination
* @throws NullPointerException if the array is null
* @throws IndexOutOfBoundsException if any index is invalid
*/
public void getChars(int startIndex, int endIndex, char destination[], int destinationIndex) {
if (startIndex < 0) {
throw new StringIndexOutOfBoundsException(startIndex);
}
if (endIndex < 0 || endIndex > length()) {
throw new StringIndexOutOfBoundsException(endIndex);
}
if (startIndex > endIndex) {
throw new StringIndexOutOfBoundsException("end < start");
}
System.arraycopy(buffer, startIndex, destination, destinationIndex, endIndex - startIndex);
}
//-----------------------------------------------------------------------
/**
* Appends the new line string to this string builder.
*
* The new line string can be altered using {@link #setNewLineText(String)}.
* This might be used to force the output to always use Unix line endings
* even when on Windows.
*
* @return this, to enable chaining
*/
public StrBuilder appendNewLine() {
if (newLine == null) {
append(SystemUtils.LINE_SEPARATOR);
return this;
}
return append(newLine);
}
/**
* Appends the text representing null to this string builder.
*
* @return this, to enable chaining
*/
public StrBuilder appendNull() {
if (nullText == null) {
return this;
}
return append(nullText);
}
/**
* Appends an object to this string builder.
* Appending null will call {@link #appendNull()}.
*
* @param obj the object to append
* @return this, to enable chaining
*/
public StrBuilder append(Object obj) {
if (obj == null) {
return appendNull();
}
return append(obj.toString());
}
/**
* Appends a string to this string builder.
* Appending null will call {@link #appendNull()}.
*
* @param str the string to append
* @return this, to enable chaining
*/
public StrBuilder append(String str) {
if (str == null) {
return appendNull();
}
int strLen = str.length();
if (strLen > 0) {
int len = length();
ensureCapacity(len + strLen);
str.getChars(0, strLen, buffer, len);
size += strLen;
}
return this;
}
/**
* Appends part of a string to this string builder.
* Appending null will call {@link #appendNull()}.
*
* @param str the string to append
* @param startIndex the start index, inclusive, must be valid
* @param length the length to append, must be valid
* @return this, to enable chaining
*/
public StrBuilder append(String str, int startIndex, int length) {
if (str == null) {
return appendNull();
}
if (startIndex < 0 || startIndex > str.length()) {
throw new StringIndexOutOfBoundsException("startIndex must be valid");
}
if (length < 0 || (startIndex + length) > str.length()) {
throw new StringIndexOutOfBoundsException("length must be valid");
}
if (length > 0) {
int len = length();
ensureCapacity(len + length);
str.getChars(startIndex, startIndex + length, buffer, len);
size += length;
}
return this;
}
/**
* Appends a string buffer to this string builder.
* Appending null will call {@link #appendNull()}.
*
* @param str the string buffer to append
* @return this, to enable chaining
*/
public StrBuilder append(StringBuffer str) {
if (str == null) {
return appendNull();
}
int strLen = str.length();
if (strLen > 0) {
int len = length();
ensureCapacity(len + strLen);
str.getChars(0, strLen, buffer, len);
size += strLen;
}
return this;
}
/**
* Appends part of a string buffer to this string builder.
* Appending null will call {@link #appendNull()}.
*
* @param str the string to append
* @param startIndex the start index, inclusive, must be valid
* @param length the length to append, must be valid
* @return this, to enable chaining
*/
public StrBuilder append(StringBuffer str, int startIndex, int length) {
if (str == null) {
return appendNull();
}
if (startIndex < 0 || startIndex > str.length()) {
throw new StringIndexOutOfBoundsException("startIndex must be valid");
}
if (length < 0 || (startIndex + length) > str.length()) {
throw new StringIndexOutOfBoundsException("length must be valid");
}
if (length > 0) {
int len = length();
ensureCapacity(len + length);
str.getChars(startIndex, startIndex + length, buffer, len);
size += length;
}
return this;
}
/**
* Appends another string builder to this string builder.
* Appending null will call {@link #appendNull()}.
*
* @param str the string builder to append
* @return this, to enable chaining
*/
public StrBuilder append(StrBuilder str) {
if (str == null) {
return appendNull();
}
int strLen = str.length();
if (strLen > 0) {
int len = length();
ensureCapacity(len + strLen);
System.arraycopy(str.buffer, 0, buffer, len, strLen);
size += strLen;
}
return this;
}
/**
* Appends part of a string builder to this string builder.
* Appending null will call {@link #appendNull()}.
*
* @param str the string to append
* @param startIndex the start index, inclusive, must be valid
* @param length the length to append, must be valid
* @return this, to enable chaining
*/
public StrBuilder append(StrBuilder str, int startIndex, int length) {
if (str == null) {
return appendNull();
}
if (startIndex < 0 || startIndex > str.length()) {
throw new StringIndexOutOfBoundsException("startIndex must be valid");
}
if (length < 0 || (startIndex + length) > str.length()) {
throw new StringIndexOutOfBoundsException("length must be valid");
}
if (length > 0) {
int len = length();
ensureCapacity(len + length);
str.getChars(startIndex, startIndex + length, buffer, len);
size += length;
}
return this;
}
/**
* Appends a char array to the string builder.
* Appending null will call {@link #appendNull()}.
*
* @param chars the char array to append
* @return this, to enable chaining
*/
public StrBuilder append(char[] chars) {
if (chars == null) {
return appendNull();
}
int strLen = chars.length;
if (strLen > 0) {
int len = length();
ensureCapacity(len + strLen);
System.arraycopy(chars, 0, buffer, len, strLen);
size += strLen;
}
return this;
}
/**
* Appends a char array to the string builder.
* Appending null will call {@link #appendNull()}.
*
* @param chars the char array to append
* @param startIndex the start index, inclusive, must be valid
* @param length the length to append, must be valid
* @return this, to enable chaining
*/
public StrBuilder append(char[] chars, int startIndex, int length) {
if (chars == null) {
return appendNull();
}
if (startIndex < 0 || startIndex > chars.length) {
throw new StringIndexOutOfBoundsException("Invalid startIndex: " + length);
}
if (length < 0 || (startIndex + length) > chars.length) {
throw new StringIndexOutOfBoundsException("Invalid length: " + length);
}
if (length > 0) {
int len = length();
ensureCapacity(len + length);
System.arraycopy(chars, startIndex, buffer, len, length);
size += length;
}
return this;
}
/**
* Appends a boolean value to the string builder.
*
* @param value the value to append
* @return this, to enable chaining
*/
public StrBuilder append(boolean value) {
if (value) {
ensureCapacity(size + 4);
buffer[size++] = 't';
buffer[size++] = 'r';
buffer[size++] = 'u';
buffer[size++] = 'e';
} else {
ensureCapacity(size + 5);
buffer[size++] = 'f';
buffer[size++] = 'a';
buffer[size++] = 'l';
buffer[size++] = 's';
buffer[size++] = 'e';
}
return this;
}
/**
* Appends a char value to the string builder.
*
* @param ch the value to append
* @return this, to enable chaining
*/
public StrBuilder append(char ch) {
int len = length();
ensureCapacity(len + 1);
buffer[size++] = ch;
return this;
}
/**
* Appends an int value to the string builder using String.valueOf.
*
* @param value the value to append
* @return this, to enable chaining
*/
public StrBuilder append(int value) {
return append(String.valueOf(value));
}
/**
* Appends a long value to the string builder using String.valueOf.
*
* @param value the value to append
* @return this, to enable chaining
*/
public StrBuilder append(long value) {
return append(String.valueOf(value));
}
/**
* Appends a float value to the string builder using String.valueOf.
*
* @param value the value to append
* @return this, to enable chaining
*/
public StrBuilder append(float value) {
return append(String.valueOf(value));
}
/**
* Appends a double value to the string builder using String.valueOf.
*
* @param value the value to append
* @return this, to enable chaining
*/
public StrBuilder append(double value) {
return append(String.valueOf(value));
}
//-----------------------------------------------------------------------
/**
* Appends an object followed by a new line to this string builder.
* Appending null will call {@link #appendNull()}.
*
* @param obj the object to append
* @return this, to enable chaining
* @since 2.3
*/
public StrBuilder appendln(Object obj) {
return append(obj).appendNewLine();
}
/**
* Appends a string followed by a new line to this string builder.
* Appending null will call {@link #appendNull()}.
*
* @param str the string to append
* @return this, to enable chaining
* @since 2.3
*/
public StrBuilder appendln(String str) {
return append(str).appendNewLine();
}
/**
* Appends part of a string followed by a new line to this string builder.
* Appending null will call {@link #appendNull()}.
*
* @param str the string to append
* @param startIndex the start index, inclusive, must be valid
* @param length the length to append, must be valid
* @return this, to enable chaining
* @since 2.3
*/
public StrBuilder appendln(String str, int startIndex, int length) {
return append(str, startIndex, length).appendNewLine();
}
/**
* Appends a string buffer followed by a new line to this string builder.
* Appending null will call {@link #appendNull()}.
*
* @param str the string buffer to append
* @return this, to enable chaining
* @since 2.3
*/
public StrBuilder appendln(StringBuffer str) {
return append(str).appendNewLine();
}
/**
* Appends part of a string buffer followed by a new line to this string builder.
* Appending null will call {@link #appendNull()}.
*
* @param str the string to append
* @param startIndex the start index, inclusive, must be valid
* @param length the length to append, must be valid
* @return this, to enable chaining
* @since 2.3
*/
public StrBuilder appendln(StringBuffer str, int startIndex, int length) {
return append(str, startIndex, length).appendNewLine();
}
/**
* Appends another string builder followed by a new line to this string builder.
* Appending null will call {@link #appendNull()}.
*
* @param str the string builder to append
* @return this, to enable chaining
* @since 2.3
*/
public StrBuilder appendln(StrBuilder str) {
return append(str).appendNewLine();
}
/**
* Appends part of a string builder followed by a new line to this string builder.
* Appending null will call {@link #appendNull()}.
*
* @param str the string to append
* @param startIndex the start index, inclusive, must be valid
* @param length the length to append, must be valid
* @return this, to enable chaining
* @since 2.3
*/
public StrBuilder appendln(StrBuilder str, int startIndex, int length) {
return append(str, startIndex, length).appendNewLine();
}
/**
* Appends a char array followed by a new line to the string builder.
* Appending null will call {@link #appendNull()}.
*
* @param chars the char array to append
* @return this, to enable chaining
* @since 2.3
*/
public StrBuilder appendln(char[] chars) {
return append(chars).appendNewLine();
}
/**
* Appends a char array followed by a new line to the string builder.
* Appending null will call {@link #appendNull()}.
*
* @param chars the char array to append
* @param startIndex the start index, inclusive, must be valid
* @param length the length to append, must be valid
* @return this, to enable chaining
* @since 2.3
*/
public StrBuilder appendln(char[] chars, int startIndex, int length) {
return append(chars, startIndex, length).appendNewLine();
}
/**
* Appends a boolean value followed by a new line to the string builder.
*
* @param value the value to append
* @return this, to enable chaining
* @since 2.3
*/
public StrBuilder appendln(boolean value) {
return append(value).appendNewLine();
}
/**
* Appends a char value followed by a new line to the string builder.
*
* @param ch the value to append
* @return this, to enable chaining
* @since 2.3
*/
public StrBuilder appendln(char ch) {
return append(ch).appendNewLine();
}
/**
* Appends an int value followed by a new line to the string builder using String.valueOf.
*
* @param value the value to append
* @return this, to enable chaining
* @since 2.3
*/
public StrBuilder appendln(int value) {
return append(value).appendNewLine();
}
/**
* Appends a long value followed by a new line to the string builder using String.valueOf.
*
* @param value the value to append
* @return this, to enable chaining
* @since 2.3
*/
public StrBuilder appendln(long value) {
return append(value).appendNewLine();
}
/**
* Appends a float value followed by a new line to the string builder using String.valueOf.
*
* @param value the value to append
* @return this, to enable chaining
* @since 2.3
*/
public StrBuilder appendln(float value) {
return append(value).appendNewLine();
}
/**
* Appends a double value followed by a new line to the string builder using String.valueOf.
*
* @param value the value to append
* @return this, to enable chaining
* @since 2.3
*/
public StrBuilder appendln(double value) {
return append(value).appendNewLine();
}
//-----------------------------------------------------------------------
/**
* Appends each item in an array to the builder without any separators.
* Appending a null array will have no effect.
* Each object is appended using {@link #append(Object)}.
*
* @param array the array to append
* @return this, to enable chaining
* @since 2.3
*/
public StrBuilder appendAll(Object[] array) {
if (array != null && array.length > 0) {
for (int i = 0; i < array.length; i++) {
append(array[i]);
}
}
return this;
}
/**
* Appends each item in a collection to the builder without any separators.
* Appending a null collection will have no effect.
* Each object is appended using {@link #append(Object)}.
*
* @param coll the collection to append
* @return this, to enable chaining
* @since 2.3
*/
public StrBuilder appendAll(Collection coll) {
if (coll != null && coll.size() > 0) {
Iterator it = coll.iterator();
while (it.hasNext()) {
append(it.next());
}
}
return this;
}
/**
* Appends each item in an iterator to the builder without any separators.
* Appending a null iterator will have no effect.
* Each object is appended using {@link #append(Object)}.
*
* @param it the iterator to append
* @return this, to enable chaining
* @since 2.3
*/
public StrBuilder appendAll(Iterator it) {
if (it != null) {
while (it.hasNext()) {
append(it.next());
}
}
return this;
}
//-----------------------------------------------------------------------
/**
* Appends an array placing separators between each value, but
* not before the first or after the last.
* Appending a null array will have no effect.
* Each object is appended using {@link #append(Object)}.
*
* @param array the array to append
* @param separator the separator to use, null means no separator
* @return this, to enable chaining
*/
public StrBuilder appendWithSeparators(Object[] array, String separator) {
if (array != null && array.length > 0) {
separator = (separator == null ? "" : separator);
append(array[0]);
for (int i = 1; i < array.length; i++) {
append(separator);
append(array[i]);
}
}
return this;
}
/**
* Appends a collection placing separators between each value, but
* not before the first or after the last.
* Appending a null collection will have no effect.
* Each object is appended using {@link #append(Object)}.
*
* @param coll the collection to append
* @param separator the separator to use, null means no separator
* @return this, to enable chaining
*/
public StrBuilder appendWithSeparators(Collection coll, String separator) {
if (coll != null && coll.size() > 0) {
separator = (separator == null ? "" : separator);
Iterator it = coll.iterator();
while (it.hasNext()) {
append(it.next());
if (it.hasNext()) {
append(separator);
}
}
}
return this;
}
/**
* Appends an iterator placing separators between each value, but
* not before the first or after the last.
* Appending a null iterator will have no effect.
* Each object is appended using {@link #append(Object)}.
*
* @param it the iterator to append
* @param separator the separator to use, null means no separator
* @return this, to enable chaining
*/
public StrBuilder appendWithSeparators(Iterator it, String separator) {
if (it != null) {
separator = (separator == null ? "" : separator);
while (it.hasNext()) {
append(it.next());
if (it.hasNext()) {
append(separator);
}
}
}
return this;
}
//-----------------------------------------------------------------------
/**
* Appends a separator if the builder is currently non-empty.
* Appending a null separator will have no effect.
* The separator is appended using {@link #append(String)}.
*
* This method is useful for adding a separator each time around the
* loop except the first.
*
* for (Iterator it = list.iterator(); it.hasNext(); ) {
* appendSeparator(",");
* append(it.next());
* }
*
* Note that for this simple example, you should use
* {@link #appendWithSeparators(Collection, String)}.
*
* @param separator the separator to use, null means no separator
* @return this, to enable chaining
* @since 2.3
*/
public StrBuilder appendSeparator(String separator) {
return appendSeparator(separator, null);
}
/**
* Appends one of both separators to the StrBuilder.
* If the builder is currently empty it will append the defaultIfEmpty-separator
* Otherwise it will append the standard-separator
*
* Appending a null separator will have no effect.
* The separator is appended using {@link #append(String)}.
*
* This method is for example useful for constructing queries
*
* StrBuilder whereClause = new StrBuilder();
* if(searchCommand.getPriority() != null) {
* whereClause.appendSeparator(" and", " where");
* whereClause.append(" priority = ?")
* }
* if(searchCommand.getComponent() != null) {
* whereClause.appendSeparator(" and", " where");
* whereClause.append(" component = ?")
* }
* selectClause.append(whereClause)
*
*
* @param standard the separator if builder is not empty, null means no separator
* @param defaultIfEmpty the separator if builder is empty, null means no separator
* @return this, to enable chaining
* @since 2.5
*/
public StrBuilder appendSeparator(String standard, String defaultIfEmpty) {
String str = isEmpty() ? defaultIfEmpty : standard;
if (str != null) {
append(str);
}
return this;
}
/**
* Appends a separator if the builder is currently non-empty.
* The separator is appended using {@link #append(char)}.
*
* This method is useful for adding a separator each time around the
* loop except the first.
*
* for (Iterator it = list.iterator(); it.hasNext(); ) {
* appendSeparator(',');
* append(it.next());
* }
*
* Note that for this simple example, you should use
* {@link #appendWithSeparators(Collection, String)}.
*
* @param separator the separator to use
* @return this, to enable chaining
* @since 2.3
*/
public StrBuilder appendSeparator(char separator) {
if (size() > 0) {
append(separator);
}
return this;
}
/**
* Append one of both separators to the builder
* If the builder is currently empty it will append the defaultIfEmpty-separator
* Otherwise it will append the standard-separator
*
* The separator is appended using {@link #append(char)}.
* @param standard the separator if builder is not empty
* @param defaultIfEmpty the separator if builder is empty
* @return this, to enable chaining
* @since 2.5
*/
public StrBuilder appendSeparator(char standard, char defaultIfEmpty) {
if (size() > 0) {
append(standard);
}
else {
append(defaultIfEmpty);
}
return this;
}
/**
* Appends a separator to the builder if the loop index is greater than zero.
* Appending a null separator will have no effect.
* The separator is appended using {@link #append(String)}.
*
* This method is useful for adding a separator each time around the
* loop except the first.
*
* for (int i = 0; i < list.size(); i++) {
* appendSeparator(",", i);
* append(list.get(i));
* }
*
* Note that for this simple example, you should use
* {@link #appendWithSeparators(Collection, String)}.
*
* @param separator the separator to use, null means no separator
* @param loopIndex the loop index
* @return this, to enable chaining
* @since 2.3
*/
public StrBuilder appendSeparator(String separator, int loopIndex) {
if (separator != null && loopIndex > 0) {
append(separator);
}
return this;
}
/**
* Appends a separator to the builder if the loop index is greater than zero.
* The separator is appended using {@link #append(char)}.
*
* This method is useful for adding a separator each time around the
* loop except the first.
*
* for (int i = 0; i < list.size(); i++) {
* appendSeparator(",", i);
* append(list.get(i));
* }
*
* Note that for this simple example, you should use
* {@link #appendWithSeparators(Collection, String)}.
*
* @param separator the separator to use
* @param loopIndex the loop index
* @return this, to enable chaining
* @since 2.3
*/
public StrBuilder appendSeparator(char separator, int loopIndex) {
if (loopIndex > 0) {
append(separator);
}
return this;
}
//-----------------------------------------------------------------------
/**
* Appends the pad character to the builder the specified number of times.
*
* @param length the length to append, negative means no append
* @param padChar the character to append
* @return this, to enable chaining
*/
public StrBuilder appendPadding(int length, char padChar) {
if (length >= 0) {
ensureCapacity(size + length);
for (int i = 0; i < length; i++) {
buffer[size++] = padChar;
}
}
return this;
}
//-----------------------------------------------------------------------
/**
* Appends an object to the builder padding on the left to a fixed width.
* The toString of the object is used.
* If the object is larger than the length, the left hand side is lost.
* If the object is null, the null text value is used.
*
* @param obj the object to append, null uses null text
* @param width the fixed field width, zero or negative has no effect
* @param padChar the pad character to use
* @return this, to enable chaining
*/
public StrBuilder appendFixedWidthPadLeft(Object obj, int width, char padChar) {
if (width > 0) {
ensureCapacity(size + width);
String str = (obj == null ? getNullText() : obj.toString());
if (str == null) {
str = "";
}
int strLen = str.length();
if (strLen >= width) {
str.getChars(strLen - width, strLen, buffer, size);
} else {
int padLen = width - strLen;
for (int i = 0; i < padLen; i++) {
buffer[size + i] = padChar;
}
str.getChars(0, strLen, buffer, size + padLen);
}
size += width;
}
return this;
}
/**
* Appends an object to the builder padding on the left to a fixed width.
* The String.valueOf of the int value is used.
* If the formatted value is larger than the length, the left hand side is lost.
*
* @param value the value to append
* @param width the fixed field width, zero or negative has no effect
* @param padChar the pad character to use
* @return this, to enable chaining
*/
public StrBuilder appendFixedWidthPadLeft(int value, int width, char padChar) {
return appendFixedWidthPadLeft(String.valueOf(value), width, padChar);
}
/**
* Appends an object to the builder padding on the right to a fixed length.
* The toString of the object is used.
* If the object is larger than the length, the right hand side is lost.
* If the object is null, null text value is used.
*
* @param obj the object to append, null uses null text
* @param width the fixed field width, zero or negative has no effect
* @param padChar the pad character to use
* @return this, to enable chaining
*/
public StrBuilder appendFixedWidthPadRight(Object obj, int width, char padChar) {
if (width > 0) {
ensureCapacity(size + width);
String str = (obj == null ? getNullText() : obj.toString());
if (str == null) {
str = "";
}
int strLen = str.length();
if (strLen >= width) {
str.getChars(0, width, buffer, size);
} else {
int padLen = width - strLen;
str.getChars(0, strLen, buffer, size);
for (int i = 0; i < padLen; i++) {
buffer[size + strLen + i] = padChar;
}
}
size += width;
}
return this;
}
/**
* Appends an object to the builder padding on the right to a fixed length.
* The String.valueOf of the int value is used.
* If the object is larger than the length, the right hand side is lost.
*
* @param value the value to append
* @param width the fixed field width, zero or negative has no effect
* @param padChar the pad character to use
* @return this, to enable chaining
*/
public StrBuilder appendFixedWidthPadRight(int value, int width, char padChar) {
return appendFixedWidthPadRight(String.valueOf(value), width, padChar);
}
//-----------------------------------------------------------------------
/**
* Inserts the string representation of an object into this builder.
* Inserting null will use the stored null text value.
*
* @param index the index to add at, must be valid
* @param obj the object to insert
* @return this, to enable chaining
* @throws IndexOutOfBoundsException if the index is invalid
*/
public StrBuilder insert(int index, Object obj) {
if (obj == null) {
return insert(index, nullText);
}
return insert(index, obj.toString());
}
/**
* Inserts the string into this builder.
* Inserting null will use the stored null text value.
*
* @param index the index to add at, must be valid
* @param str the string to insert
* @return this, to enable chaining
* @throws IndexOutOfBoundsException if the index is invalid
*/
public StrBuilder insert(int index, String str) {
validateIndex(index);
if (str == null) {
str = nullText;
}
int strLen = (str == null ? 0 : str.length());
if (strLen > 0) {
int newSize = size + strLen;
ensureCapacity(newSize);
System.arraycopy(buffer, index, buffer, index + strLen, size - index);
size = newSize;
str.getChars(0, strLen, buffer, index); // str cannot be null here
}
return this;
}
/**
* Inserts the character array into this builder.
* Inserting null will use the stored null text value.
*
* @param index the index to add at, must be valid
* @param chars the char array to insert
* @return this, to enable chaining
* @throws IndexOutOfBoundsException if the index is invalid
*/
public StrBuilder insert(int index, char chars[]) {
validateIndex(index);
if (chars == null) {
return insert(index, nullText);
}
int len = chars.length;
if (len > 0) {
ensureCapacity(size + len);
System.arraycopy(buffer, index, buffer, index + len, size - index);
System.arraycopy(chars, 0, buffer, index, len);
size += len;
}
return this;
}
/**
* Inserts part of the character array into this builder.
* Inserting null will use the stored null text value.
*
* @param index the index to add at, must be valid
* @param chars the char array to insert
* @param offset the offset into the character array to start at, must be valid
* @param length the length of the character array part to copy, must be positive
* @return this, to enable chaining
* @throws IndexOutOfBoundsException if any index is invalid
*/
public StrBuilder insert(int index, char chars[], int offset, int length) {
validateIndex(index);
if (chars == null) {
return insert(index, nullText);
}
if (offset < 0 || offset > chars.length) {
throw new StringIndexOutOfBoundsException("Invalid offset: " + offset);
}
if (length < 0 || offset + length > chars.length) {
throw new StringIndexOutOfBoundsException("Invalid length: " + length);
}
if (length > 0) {
ensureCapacity(size + length);
System.arraycopy(buffer, index, buffer, index + length, size - index);
System.arraycopy(chars, offset, buffer, index, length);
size += length;
}
return this;
}
/**
* Inserts the value into this builder.
*
* @param index the index to add at, must be valid
* @param value the value to insert
* @return this, to enable chaining
* @throws IndexOutOfBoundsException if the index is invalid
*/
public StrBuilder insert(int index, boolean value) {
validateIndex(index);
if (value) {
ensureCapacity(size + 4);
System.arraycopy(buffer, index, buffer, index + 4, size - index);
buffer[index++] = 't';
buffer[index++] = 'r';
buffer[index++] = 'u';
buffer[index] = 'e';
size += 4;
} else {
ensureCapacity(size + 5);
System.arraycopy(buffer, index, buffer, index + 5, size - index);
buffer[index++] = 'f';
buffer[index++] = 'a';
buffer[index++] = 'l';
buffer[index++] = 's';
buffer[index] = 'e';
size += 5;
}
return this;
}
/**
* Inserts the value into this builder.
*
* @param index the index to add at, must be valid
* @param value the value to insert
* @return this, to enable chaining
* @throws IndexOutOfBoundsException if the index is invalid
*/
public StrBuilder insert(int index, char value) {
validateIndex(index);
ensureCapacity(size + 1);
System.arraycopy(buffer, index, buffer, index + 1, size - index);
buffer[index] = value;
size++;
return this;
}
/**
* Inserts the value into this builder.
*
* @param index the index to add at, must be valid
* @param value the value to insert
* @return this, to enable chaining
* @throws IndexOutOfBoundsException if the index is invalid
*/
public StrBuilder insert(int index, int value) {
return insert(index, String.valueOf(value));
}
/**
* Inserts the value into this builder.
*
* @param index the index to add at, must be valid
* @param value the value to insert
* @return this, to enable chaining
* @throws IndexOutOfBoundsException if the index is invalid
*/
public StrBuilder insert(int index, long value) {
return insert(index, String.valueOf(value));
}
/**
* Inserts the value into this builder.
*
* @param index the index to add at, must be valid
* @param value the value to insert
* @return this, to enable chaining
* @throws IndexOutOfBoundsException if the index is invalid
*/
public StrBuilder insert(int index, float value) {
return insert(index, String.valueOf(value));
}
/**
* Inserts the value into this builder.
*
* @param index the index to add at, must be valid
* @param value the value to insert
* @return this, to enable chaining
* @throws IndexOutOfBoundsException if the index is invalid
*/
public StrBuilder insert(int index, double value) {
return insert(index, String.valueOf(value));
}
//-----------------------------------------------------------------------
/**
* Internal method to delete a range without validation.
*
* @param startIndex the start index, must be valid
* @param endIndex the end index (exclusive), must be valid
* @param len the length, must be valid
* @throws IndexOutOfBoundsException if any index is invalid
*/
private void deleteImpl(int startIndex, int endIndex, int len) {
System.arraycopy(buffer, endIndex, buffer, startIndex, size - endIndex);
size -= len;
}
/**
* Deletes the characters between the two specified indices.
*
* @param startIndex the start index, inclusive, must be valid
* @param endIndex the end index, exclusive, must be valid except
* that if too large it is treated as end of string
* @return this, to enable chaining
* @throws IndexOutOfBoundsException if the index is invalid
*/
public StrBuilder delete(int startIndex, int endIndex) {
endIndex = validateRange(startIndex, endIndex);
int len = endIndex - startIndex;
if (len > 0) {
deleteImpl(startIndex, endIndex, len);
}
return this;
}
//-----------------------------------------------------------------------
/**
* Deletes the character wherever it occurs in the builder.
*
* @param ch the character to delete
* @return this, to enable chaining
*/
public StrBuilder deleteAll(char ch) {
for (int i = 0; i < size; i++) {
if (buffer[i] == ch) {
int start = i;
while (++i < size) {
if (buffer[i] != ch) {
break;
}
}
int len = i - start;
deleteImpl(start, i, len);
i -= len;
}
}
return this;
}
/**
* Deletes the character wherever it occurs in the builder.
*
* @param ch the character to delete
* @return this, to enable chaining
*/
public StrBuilder deleteFirst(char ch) {
for (int i = 0; i < size; i++) {
if (buffer[i] == ch) {
deleteImpl(i, i + 1, 1);
break;
}
}
return this;
}
//-----------------------------------------------------------------------
/**
* Deletes the string wherever it occurs in the builder.
*
* @param str the string to delete, null causes no action
* @return this, to enable chaining
*/
public StrBuilder deleteAll(String str) {
int len = (str == null ? 0 : str.length());
if (len > 0) {
int index = indexOf(str, 0);
while (index >= 0) {
deleteImpl(index, index + len, len);
index = indexOf(str, index);
}
}
return this;
}
/**
* Deletes the string wherever it occurs in the builder.
*
* @param str the string to delete, null causes no action
* @return this, to enable chaining
*/
public StrBuilder deleteFirst(String str) {
int len = (str == null ? 0 : str.length());
if (len > 0) {
int index = indexOf(str, 0);
if (index >= 0) {
deleteImpl(index, index + len, len);
}
}
return this;
}
//-----------------------------------------------------------------------
/**
* Deletes all parts of the builder that the matcher matches.
*
* Matchers can be used to perform advanced deletion behaviour.
* For example you could write a matcher to delete all occurances
* where the character 'a' is followed by a number.
*
* @param matcher the matcher to use to find the deletion, null causes no action
* @return this, to enable chaining
*/
public StrBuilder deleteAll(StrMatcher matcher) {
return replace(matcher, null, 0, size, -1);
}
/**
* Deletes the first match within the builder using the specified matcher.
*
* Matchers can be used to perform advanced deletion behaviour.
* For example you could write a matcher to delete
* where the character 'a' is followed by a number.
*
* @param matcher the matcher to use to find the deletion, null causes no action
* @return this, to enable chaining
*/
public StrBuilder deleteFirst(StrMatcher matcher) {
return replace(matcher, null, 0, size, 1);
}
//-----------------------------------------------------------------------
/**
* Internal method to delete a range without validation.
*
* @param startIndex the start index, must be valid
* @param endIndex the end index (exclusive), must be valid
* @param removeLen the length to remove (endIndex - startIndex), must be valid
* @param insertStr the string to replace with, null means delete range
* @param insertLen the length of the insert string, must be valid
* @throws IndexOutOfBoundsException if any index is invalid
*/
private void replaceImpl(int startIndex, int endIndex, int removeLen, String insertStr, int insertLen) {
int newSize = size - removeLen + insertLen;
if (insertLen != removeLen) {
ensureCapacity(newSize);
System.arraycopy(buffer, endIndex, buffer, startIndex + insertLen, size - endIndex);
size = newSize;
}
if (insertLen > 0) {
insertStr.getChars(0, insertLen, buffer, startIndex);
}
}
/**
* Replaces a portion of the string builder with another string.
* The length of the inserted string does not have to match the removed length.
*
* @param startIndex the start index, inclusive, must be valid
* @param endIndex the end index, exclusive, must be valid except
* that if too large it is treated as end of string
* @param replaceStr the string to replace with, null means delete range
* @return this, to enable chaining
* @throws IndexOutOfBoundsException if the index is invalid
*/
public StrBuilder replace(int startIndex, int endIndex, String replaceStr) {
endIndex = validateRange(startIndex, endIndex);
int insertLen = (replaceStr == null ? 0 : replaceStr.length());
replaceImpl(startIndex, endIndex, endIndex - startIndex, replaceStr, insertLen);
return this;
}
//-----------------------------------------------------------------------
/**
* Replaces the search character with the replace character
* throughout the builder.
*
* @param search the search character
* @param replace the replace character
* @return this, to enable chaining
*/
public StrBuilder replaceAll(char search, char replace) {
if (search != replace) {
for (int i = 0; i < size; i++) {
if (buffer[i] == search) {
buffer[i] = replace;
}
}
}
return this;
}
/**
* Replaces the first instance of the search character with the
* replace character in the builder.
*
* @param search the search character
* @param replace the replace character
* @return this, to enable chaining
*/
public StrBuilder replaceFirst(char search, char replace) {
if (search != replace) {
for (int i = 0; i < size; i++) {
if (buffer[i] == search) {
buffer[i] = replace;
break;
}
}
}
return this;
}
//-----------------------------------------------------------------------
/**
* Replaces the search string with the replace string throughout the builder.
*
* @param searchStr the search string, null causes no action to occur
* @param replaceStr the replace string, null is equivalent to an empty string
* @return this, to enable chaining
*/
public StrBuilder replaceAll(String searchStr, String replaceStr) {
int searchLen = (searchStr == null ? 0 : searchStr.length());
if (searchLen > 0) {
int replaceLen = (replaceStr == null ? 0 : replaceStr.length());
int index = indexOf(searchStr, 0);
while (index >= 0) {
replaceImpl(index, index + searchLen, searchLen, replaceStr, replaceLen);
index = indexOf(searchStr, index + replaceLen);
}
}
return this;
}
/**
* Replaces the first instance of the search string with the replace string.
*
* @param searchStr the search string, null causes no action to occur
* @param replaceStr the replace string, null is equivalent to an empty string
* @return this, to enable chaining
*/
public StrBuilder replaceFirst(String searchStr, String replaceStr) {
int searchLen = (searchStr == null ? 0 : searchStr.length());
if (searchLen > 0) {
int index = indexOf(searchStr, 0);
if (index >= 0) {
int replaceLen = (replaceStr == null ? 0 : replaceStr.length());
replaceImpl(index, index + searchLen, searchLen, replaceStr, replaceLen);
}
}
return this;
}
//-----------------------------------------------------------------------
/**
* Replaces all matches within the builder with the replace string.
*
* Matchers can be used to perform advanced replace behaviour.
* For example you could write a matcher to replace all occurances
* where the character 'a' is followed by a number.
*
* @param matcher the matcher to use to find the deletion, null causes no action
* @param replaceStr the replace string, null is equivalent to an empty string
* @return this, to enable chaining
*/
public StrBuilder replaceAll(StrMatcher matcher, String replaceStr) {
return replace(matcher, replaceStr, 0, size, -1);
}
/**
* Replaces the first match within the builder with the replace string.
*
* Matchers can be used to perform advanced replace behaviour.
* For example you could write a matcher to replace
* where the character 'a' is followed by a number.
*
* @param matcher the matcher to use to find the deletion, null causes no action
* @param replaceStr the replace string, null is equivalent to an empty string
* @return this, to enable chaining
*/
public StrBuilder replaceFirst(StrMatcher matcher, String replaceStr) {
return replace(matcher, replaceStr, 0, size, 1);
}
// -----------------------------------------------------------------------
/**
* Advanced search and replaces within the builder using a matcher.
*
* Matchers can be used to perform advanced behaviour.
* For example you could write a matcher to delete all occurances
* where the character 'a' is followed by a number.
*
* @param matcher the matcher to use to find the deletion, null causes no action
* @param replaceStr the string to replace the match with, null is a delete
* @param startIndex the start index, inclusive, must be valid
* @param endIndex the end index, exclusive, must be valid except
* that if too large it is treated as end of string
* @param replaceCount the number of times to replace, -1 for replace all
* @return this, to enable chaining
* @throws IndexOutOfBoundsException if start index is invalid
*/
public StrBuilder replace(
StrMatcher matcher, String replaceStr,
int startIndex, int endIndex, int replaceCount) {
endIndex = validateRange(startIndex, endIndex);
return replaceImpl(matcher, replaceStr, startIndex, endIndex, replaceCount);
}
/**
* Replaces within the builder using a matcher.
*
* Matchers can be used to perform advanced behaviour.
* For example you could write a matcher to delete all occurances
* where the character 'a' is followed by a number.
*
* @param matcher the matcher to use to find the deletion, null causes no action
* @param replaceStr the string to replace the match with, null is a delete
* @param from the start index, must be valid
* @param to the end index (exclusive), must be valid
* @param replaceCount the number of times to replace, -1 for replace all
* @return this, to enable chaining
* @throws IndexOutOfBoundsException if any index is invalid
*/
private StrBuilder replaceImpl(
StrMatcher matcher, String replaceStr,
int from, int to, int replaceCount) {
if (matcher == null || size == 0) {
return this;
}
int replaceLen = (replaceStr == null ? 0 : replaceStr.length());
char[] buf = buffer;
for (int i = from; i < to && replaceCount != 0; i++) {
int removeLen = matcher.isMatch(buf, i, from, to);
if (removeLen > 0) {
replaceImpl(i, i + removeLen, removeLen, replaceStr, replaceLen);
to = to - removeLen + replaceLen;
i = i + replaceLen - 1;
if (replaceCount > 0) {
replaceCount--;
}
}
}
return this;
}
//-----------------------------------------------------------------------
/**
* Reverses the string builder placing each character in the opposite index.
*
* @return this, to enable chaining
*/
public StrBuilder reverse() {
if (size == 0) {
return this;
}
int half = size / 2;
char[] buf = buffer;
for (int leftIdx = 0, rightIdx = size - 1; leftIdx < half; leftIdx++,rightIdx--) {
char swap = buf[leftIdx];
buf[leftIdx] = buf[rightIdx];
buf[rightIdx] = swap;
}
return this;
}
//-----------------------------------------------------------------------
/**
* Trims the builder by removing characters less than or equal to a space
* from the beginning and end.
*
* @return this, to enable chaining
*/
public StrBuilder trim() {
if (size == 0) {
return this;
}
int len = size;
char[] buf = buffer;
int pos = 0;
while (pos < len && buf[pos] <= ' ') {
pos++;
}
while (pos < len && buf[len - 1] <= ' ') {
len--;
}
if (len < size) {
delete(len, size);
}
if (pos > 0) {
delete(0, pos);
}
return this;
}
//-----------------------------------------------------------------------
/**
* Checks whether this builder starts with the specified string.
*
* Note that this method handles null input quietly, unlike String.
*
* @param str the string to search for, null returns false
* @return true if the builder starts with the string
*/
public boolean startsWith(String str) {
if (str == null) {
return false;
}
int len = str.length();
if (len == 0) {
return true;
}
if (len > size) {
return false;
}
for (int i = 0; i < len; i++) {
if (buffer[i] != str.charAt(i)) {
return false;
}
}
return true;
}
/**
* Checks whether this builder ends with the specified string.
*
* Note that this method handles null input quietly, unlike String.
*
* @param str the string to search for, null returns false
* @return true if the builder ends with the string
*/
public boolean endsWith(String str) {
if (str == null) {
return false;
}
int len = str.length();
if (len == 0) {
return true;
}
if (len > size) {
return false;
}
int pos = size - len;
for (int i = 0; i < len; i++,pos++) {
if (buffer[pos] != str.charAt(i)) {
return false;
}
}
return true;
}
//-----------------------------------------------------------------------
/**
* Extracts a portion of this string builder as a string.
*
* @param start the start index, inclusive, must be valid
* @return the new string
* @throws IndexOutOfBoundsException if the index is invalid
*/
public String substring(int start) {
return substring(start, size);
}
/**
* Extracts a portion of this string builder as a string.
*
* Note: This method treats an endIndex greater than the length of the
* builder as equal to the length of the builder, and continues
* without error, unlike StringBuffer or String.
*
* @param startIndex the start index, inclusive, must be valid
* @param endIndex the end index, exclusive, must be valid except
* that if too large it is treated as end of string
* @return the new string
* @throws IndexOutOfBoundsException if the index is invalid
*/
public String substring(int startIndex, int endIndex) {
endIndex = validateRange(startIndex, endIndex);
return new String(buffer, startIndex, endIndex - startIndex);
}
/**
* Extracts the leftmost characters from the string builder without
* throwing an exception.
*
* This method extracts the left length characters from
* the builder. If this many characters are not available, the whole
* builder is returned. Thus the returned string may be shorter than the
* length requested.
*
* @param length the number of characters to extract, negative returns empty string
* @return the new string
*/
public String leftString(int length) {
if (length <= 0) {
return "";
} else if (length >= size) {
return new String(buffer, 0, size);
} else {
return new String(buffer, 0, length);
}
}
/**
* Extracts the rightmost characters from the string builder without
* throwing an exception.
*
* This method extracts the right length characters from
* the builder. If this many characters are not available, the whole
* builder is returned. Thus the returned string may be shorter than the
* length requested.
*
* @param length the number of characters to extract, negative returns empty string
* @return the new string
*/
public String rightString(int length) {
if (length <= 0) {
return "";
} else if (length >= size) {
return new String(buffer, 0, size);
} else {
return new String(buffer, size - length, length);
}
}
/**
* Extracts some characters from the middle of the string builder without
* throwing an exception.
*
* This method extracts length characters from the builder
* at the specified index.
* If the index is negative it is treated as zero.
* If the index is greater than the builder size, it is treated as the builder size.
* If the length is negative, the empty string is returned.
* If insufficient characters are available in the builder, as much as possible is returned.
* Thus the returned string may be shorter than the length requested.
*
* @param index the index to start at, negative means zero
* @param length the number of characters to extract, negative returns empty string
* @return the new string
*/
public String midString(int index, int length) {
if (index < 0) {
index = 0;
}
if (length <= 0 || index >= size) {
return "";
}
if (size <= index + length) {
return new String(buffer, index, size - index);
} else {
return new String(buffer, index, length);
}
}
//-----------------------------------------------------------------------
/**
* Checks if the string builder contains the specified char.
*
* @param ch the character to find
* @return true if the builder contains the character
*/
public boolean contains(char ch) {
char[] thisBuf = buffer;
for (int i = 0; i < this.size; i++) {
if (thisBuf[i] == ch) {
return true;
}
}
return false;
}
/**
* Checks if the string builder contains the specified string.
*
* @param str the string to find
* @return true if the builder contains the string
*/
public boolean contains(String str) {
return indexOf(str, 0) >= 0;
}
/**
* Checks if the string builder contains a string matched using the
* specified matcher.
*
* Matchers can be used to perform advanced searching behaviour.
* For example you could write a matcher to search for the character
* 'a' followed by a number.
*
* @param matcher the matcher to use, null returns -1
* @return true if the matcher finds a match in the builder
*/
public boolean contains(StrMatcher matcher) {
return indexOf(matcher, 0) >= 0;
}
//-----------------------------------------------------------------------
/**
* Searches the string builder to find the first reference to the specified char.
*
* @param ch the character to find
* @return the first index of the character, or -1 if not found
*/
public int indexOf(char ch) {
return indexOf(ch, 0);
}
/**
* Searches the string builder to find the first reference to the specified char.
*
* @param ch the character to find
* @param startIndex the index to start at, invalid index rounded to edge
* @return the first index of the character, or -1 if not found
*/
public int indexOf(char ch, int startIndex) {
startIndex = (startIndex < 0 ? 0 : startIndex);
if (startIndex >= size) {
return -1;
}
char[] thisBuf = buffer;
for (int i = startIndex; i < size; i++) {
if (thisBuf[i] == ch) {
return i;
}
}
return -1;
}
/**
* Searches the string builder to find the first reference to the specified string.
*
* Note that a null input string will return -1, whereas the JDK throws an exception.
*
* @param str the string to find, null returns -1
* @return the first index of the string, or -1 if not found
*/
public int indexOf(String str) {
return indexOf(str, 0);
}
/**
* Searches the string builder to find the first reference to the specified
* string starting searching from the given index.
*
* Note that a null input string will return -1, whereas the JDK throws an exception.
*
* @param str the string to find, null returns -1
* @param startIndex the index to start at, invalid index rounded to edge
* @return the first index of the string, or -1 if not found
*/
public int indexOf(String str, int startIndex) {
startIndex = (startIndex < 0 ? 0 : startIndex);
if (str == null || startIndex >= size) {
return -1;
}
int strLen = str.length();
if (strLen == 1) {
return indexOf(str.charAt(0), startIndex);
}
if (strLen == 0) {
return startIndex;
}
if (strLen > size) {
return -1;
}
char[] thisBuf = buffer;
int len = size - strLen + 1;
outer:
for (int i = startIndex; i < len; i++) {
for (int j = 0; j < strLen; j++) {
if (str.charAt(j) != thisBuf[i + j]) {
continue outer;
}
}
return i;
}
return -1;
}
/**
* Searches the string builder using the matcher to find the first match.
*
* Matchers can be used to perform advanced searching behaviour.
* For example you could write a matcher to find the character 'a'
* followed by a number.
*
* @param matcher the matcher to use, null returns -1
* @return the first index matched, or -1 if not found
*/
public int indexOf(StrMatcher matcher) {
return indexOf(matcher, 0);
}
/**
* Searches the string builder using the matcher to find the first
* match searching from the given index.
*
* Matchers can be used to perform advanced searching behaviour.
* For example you could write a matcher to find the character 'a'
* followed by a number.
*
* @param matcher the matcher to use, null returns -1
* @param startIndex the index to start at, invalid index rounded to edge
* @return the first index matched, or -1 if not found
*/
public int indexOf(StrMatcher matcher, int startIndex) {
startIndex = (startIndex < 0 ? 0 : startIndex);
if (matcher == null || startIndex >= size) {
return -1;
}
int len = size;
char[] buf = buffer;
for (int i = startIndex; i < len; i++) {
if (matcher.isMatch(buf, i, startIndex, len) > 0) {
return i;
}
}
return -1;
}
//-----------------------------------------------------------------------
/**
* Searches the string builder to find the last reference to the specified char.
*
* @param ch the character to find
* @return the last index of the character, or -1 if not found
*/
public int lastIndexOf(char ch) {
return lastIndexOf(ch, size - 1);
}
/**
* Searches the string builder to find the last reference to the specified char.
*
* @param ch the character to find
* @param startIndex the index to start at, invalid index rounded to edge
* @return the last index of the character, or -1 if not found
*/
public int lastIndexOf(char ch, int startIndex) {
startIndex = (startIndex >= size ? size - 1 : startIndex);
if (startIndex < 0) {
return -1;
}
for (int i = startIndex; i >= 0; i--) {
if (buffer[i] == ch) {
return i;
}
}
return -1;
}
/**
* Searches the string builder to find the last reference to the specified string.
*
* Note that a null input string will return -1, whereas the JDK throws an exception.
*
* @param str the string to find, null returns -1
* @return the last index of the string, or -1 if not found
*/
public int lastIndexOf(String str) {
return lastIndexOf(str, size - 1);
}
/**
* Searches the string builder to find the last reference to the specified
* string starting searching from the given index.
*
* Note that a null input string will return -1, whereas the JDK throws an exception.
*
* @param str the string to find, null returns -1
* @param startIndex the index to start at, invalid index rounded to edge
* @return the last index of the string, or -1 if not found
*/
public int lastIndexOf(String str, int startIndex) {
startIndex = (startIndex >= size ? size - 1 : startIndex);
if (str == null || startIndex < 0) {
return -1;
}
int strLen = str.length();
if (strLen > 0 && strLen <= size) {
if (strLen == 1) {
return lastIndexOf(str.charAt(0), startIndex);
}
outer:
for (int i = startIndex - strLen + 1; i >= 0; i--) {
for (int j = 0; j < strLen; j++) {
if (str.charAt(j) != buffer[i + j]) {
continue outer;
}
}
return i;
}
} else if (strLen == 0) {
return startIndex;
}
return -1;
}
/**
* Searches the string builder using the matcher to find the last match.
*
* Matchers can be used to perform advanced searching behaviour.
* For example you could write a matcher to find the character 'a'
* followed by a number.
*
* @param matcher the matcher to use, null returns -1
* @return the last index matched, or -1 if not found
*/
public int lastIndexOf(StrMatcher matcher) {
return lastIndexOf(matcher, size);
}
/**
* Searches the string builder using the matcher to find the last
* match searching from the given index.
*
* Matchers can be used to perform advanced searching behaviour.
* For example you could write a matcher to find the character 'a'
* followed by a number.
*
* @param matcher the matcher to use, null returns -1
* @param startIndex the index to start at, invalid index rounded to edge
* @return the last index matched, or -1 if not found
*/
public int lastIndexOf(StrMatcher matcher, int startIndex) {
startIndex = (startIndex >= size ? size - 1 : startIndex);
if (matcher == null || startIndex < 0) {
return -1;
}
char[] buf = buffer;
int endIndex = startIndex + 1;
for (int i = startIndex; i >= 0; i--) {
if (matcher.isMatch(buf, i, 0, endIndex) > 0) {
return i;
}
}
return -1;
}
//-----------------------------------------------------------------------
/**
* Creates a tokenizer that can tokenize the contents of this builder.
*
* This method allows the contents of this builder to be tokenized.
* The tokenizer will be setup by default to tokenize on space, tab,
* newline and formfeed (as per StringTokenizer). These values can be
* changed on the tokenizer class, before retrieving the tokens.
*
* The returned tokenizer is linked to this builder. You may intermix
* calls to the buider and tokenizer within certain limits, however
* there is no synchronization. Once the tokenizer has been used once,
* it must be {@link StrTokenizer#reset() reset} to pickup the latest
* changes in the builder. For example:
*
* StrBuilder b = new StrBuilder();
* b.append("a b ");
* StrTokenizer t = b.asTokenizer();
* String[] tokens1 = t.getTokenArray(); // returns a,b
* b.append("c d ");
* String[] tokens2 = t.getTokenArray(); // returns a,b (c and d ignored)
* t.reset(); // reset causes builder changes to be picked up
* String[] tokens3 = t.getTokenArray(); // returns a,b,c,d
*
* In addition to simply intermixing appends and tokenization, you can also
* call the set methods on the tokenizer to alter how it tokenizes. Just
* remember to call reset when you want to pickup builder changes.
*
* Calling {@link StrTokenizer#reset(String)} or {@link StrTokenizer#reset(char[])}
* with a non-null value will break the link with the builder.
*
* @return a tokenizer that is linked to this builder
*/
public StrTokenizer asTokenizer() {
return new StrBuilderTokenizer();
}
//-----------------------------------------------------------------------
/**
* Gets the contents of this builder as a Reader.
*
* This method allows the contents of the builder to be read
* using any standard method that expects a Reader.
*
* To use, simply create a StrBuilder, populate it with
* data, call asReader, and then read away.
*
* The internal character array is shared between the builder and the reader.
* This allows you to append to the builder after creating the reader,
* and the changes will be picked up.
* Note however, that no synchronization occurs, so you must perform
* all operations with the builder and the reader in one thread.
*
* The returned reader supports marking, and ignores the flush method.
*
* @return a reader that reads from this builder
*/
public Reader asReader() {
return new StrBuilderReader();
}
//-----------------------------------------------------------------------
/**
* Gets this builder as a Writer that can be written to.
*
* This method allows you to populate the contents of the builder
* using any standard method that takes a Writer.
*
* To use, simply create a StrBuilder,
* call asWriter, and populate away. The data is available
* at any time using the methods of the StrBuilder.
*
* The internal character array is shared between the builder and the writer.
* This allows you to intermix calls that append to the builder and
* write using the writer and the changes will be occur correctly.
* Note however, that no synchronization occurs, so you must perform
* all operations with the builder and the writer in one thread.
*
* The returned writer ignores the close and flush methods.
*
* @return a writer that populates this builder
*/
public Writer asWriter() {
return new StrBuilderWriter();
}
//-----------------------------------------------------------------------
// /**
// * Gets a String version of the string builder by calling the internal
// * constructor of String by reflection.
// *
// * WARNING: You must not use the StrBuilder after calling this method
// * as the buffer is now shared with the String object. To ensure this,
// * the internal character array is set to null, so you will get
// * NullPointerExceptions on all method calls.
// *
// * @return the builder as a String
// */
// public String toSharedString() {
// try {
// Constructor con = String.class.getDeclaredConstructor(
// new Class[] {int.class, int.class, char[].class});
// con.setAccessible(true);
// char[] buffer = buf;
// buf = null;
// size = -1;
// nullText = null;
// return (String) con.newInstance(
// new Object[] {new Integer(0), new Integer(size), buffer});
//
// } catch (Exception ex) {
// ex.printStackTrace();
// throw new UnsupportedOperationException("StrBuilder.toSharedString is unsupported: " + ex.getMessage());
// }
// }
//-----------------------------------------------------------------------
/**
* Checks the contents of this builder against another to see if they
* contain the same character content ignoring case.
*
* @param other the object to check, null returns false
* @return true if the builders contain the same characters in the same order
*/
public boolean equalsIgnoreCase(StrBuilder other) {
if (this == other) {
return true;
}
if (this.size != other.size) {
return false;
}
char thisBuf[] = this.buffer;
char otherBuf[] = other.buffer;
for (int i = size - 1; i >= 0; i--) {
char c1 = thisBuf[i];
char c2 = otherBuf[i];
if (c1 != c2 && Character.toUpperCase(c1) != Character.toUpperCase(c2)) {
return false;
}
}
return true;
}
/**
* Checks the contents of this builder against another to see if they
* contain the same character content.
*
* @param other the object to check, null returns false
* @return true if the builders contain the same characters in the same order
*/
public boolean equals(StrBuilder other) {
if (this == other) {
return true;
}
if (this.size != other.size) {
return false;
}
char thisBuf[] = this.buffer;
char otherBuf[] = other.buffer;
for (int i = size - 1; i >= 0; i--) {
if (thisBuf[i] != otherBuf[i]) {
return false;
}
}
return true;
}
/**
* Checks the contents of this builder against another to see if they
* contain the same character content.
*
* @param obj the object to check, null returns false
* @return true if the builders contain the same characters in the same order
*/
public boolean equals(Object obj) {
if (obj instanceof StrBuilder) {
return equals((StrBuilder) obj);
}
return false;
}
/**
* Gets a suitable hash code for this builder.
*
* @return a hash code
*/
public int hashCode() {
char buf[] = buffer;
int hash = 0;
for (int i = size - 1; i >= 0; i--) {
hash = 31 * hash + buf[i];
}
return hash;
}
//-----------------------------------------------------------------------
/**
* Gets a String version of the string builder, creating a new instance
* each time the method is called.
*
* Note that unlike StringBuffer, the string version returned is
* independent of the string builder.
*
* @return the builder as a String
*/
public String toString() {
return new String(buffer, 0, size);
}
/**
* Gets a StringBuffer version of the string builder, creating a
* new instance each time the method is called.
*
* @return the builder as a StringBuffer
*/
public StringBuffer toStringBuffer() {
return new StringBuffer(size).append(buffer, 0, size);
}
/**
* Clone this object.
*
* @return a clone of this object
* @throws CloneNotSupportedException if clone is not supported
* @since 2.6
*/
public Object clone() throws CloneNotSupportedException {
StrBuilder clone = (StrBuilder)super.clone();
clone.buffer = new char[buffer.length];
System.arraycopy(buffer, 0, clone.buffer, 0, buffer.length);
return clone;
}
//-----------------------------------------------------------------------
/**
* Validates parameters defining a range of the builder.
*
* @param startIndex the start index, inclusive, must be valid
* @param endIndex the end index, exclusive, must be valid except
* that if too large it is treated as end of string
* @return the new string
* @throws IndexOutOfBoundsException if the index is invalid
*/
protected int validateRange(int startIndex, int endIndex) {
if (startIndex < 0) {
throw new StringIndexOutOfBoundsException(startIndex);
}
if (endIndex > size) {
endIndex = size;
}
if (startIndex > endIndex) {
throw new StringIndexOutOfBoundsException("end < start");
}
return endIndex;
}
/**
* Validates parameters defining a single index in the builder.
*
* @param index the index, must be valid
* @throws IndexOutOfBoundsException if the index is invalid
*/
protected void validateIndex(int index) {
if (index < 0 || index > size) {
throw new StringIndexOutOfBoundsException(index);
}
}
//-----------------------------------------------------------------------
/**
* Inner class to allow StrBuilder to operate as a tokenizer.
*/
class StrBuilderTokenizer extends StrTokenizer {
/**
* Default constructor.
*/
StrBuilderTokenizer() {
super();
}
/** {@inheritDoc} */
protected List tokenize(char[] chars, int offset, int count) {
if (chars == null) {
return super.tokenize(StrBuilder.this.buffer, 0, StrBuilder.this.size());
} else {
return super.tokenize(chars, offset, count);
}
}
/** {@inheritDoc} */
public String getContent() {
String str = super.getContent();
if (str == null) {
return StrBuilder.this.toString();
} else {
return str;
}
}
}
//-----------------------------------------------------------------------
/**
* Inner class to allow StrBuilder to operate as a writer.
*/
class StrBuilderReader extends Reader {
/** The current stream position. */
private int pos;
/** The last mark position. */
private int mark;
/**
* Default constructor.
*/
StrBuilderReader() {
super();
}
/** {@inheritDoc} */
public void close() {
// do nothing
}
/** {@inheritDoc} */
public int read() {
if (ready() == false) {
return -1;
}
return StrBuilder.this.charAt(pos++);
}
/** {@inheritDoc} */
public int read(char b[], int off, int len) {
if (off < 0 || len < 0 || off > b.length ||
(off + len) > b.length || (off + len) < 0) {
throw new IndexOutOfBoundsException();
}
if (len == 0) {
return 0;
}
if (pos >= StrBuilder.this.size()) {
return -1;
}
if (pos + len > size()) {
len = StrBuilder.this.size() - pos;
}
StrBuilder.this.getChars(pos, pos + len, b, off);
pos += len;
return len;
}
/** {@inheritDoc} */
public long skip(long n) {
if (pos + n > StrBuilder.this.size()) {
n = StrBuilder.this.size() - pos;
}
if (n < 0) {
return 0;
}
pos += n;
return n;
}
/** {@inheritDoc} */
public boolean ready() {
return pos < StrBuilder.this.size();
}
/** {@inheritDoc} */
public boolean markSupported() {
return true;
}
/** {@inheritDoc} */
public void mark(int readAheadLimit) {
mark = pos;
}
/** {@inheritDoc} */
public void reset() {
pos = mark;
}
}
//-----------------------------------------------------------------------
/**
* Inner class to allow StrBuilder to operate as a writer.
*/
class StrBuilderWriter extends Writer {
/**
* Default constructor.
*/
StrBuilderWriter() {
super();
}
/** {@inheritDoc} */
public void close() {
// do nothing
}
/** {@inheritDoc} */
public void flush() {
// do nothing
}
/** {@inheritDoc} */
public void write(int c) {
StrBuilder.this.append((char) c);
}
/** {@inheritDoc} */
public void write(char[] cbuf) {
StrBuilder.this.append(cbuf);
}
/** {@inheritDoc} */
public void write(char[] cbuf, int off, int len) {
StrBuilder.this.append(cbuf, off, len);
}
/** {@inheritDoc} */
public void write(String str) {
StrBuilder.this.append(str);
}
/** {@inheritDoc} */
public void write(String str, int off, int len) {
StrBuilder.this.append(str, off, len);
}
}
}