org.apache.bval.util.StringUtils 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.bval.util;
import java.util.ArrayList;
import java.util.Collection;
import java.util.Iterator;
import java.util.List;
public final class StringUtils {
private StringUtils() {
}
/**
* Taken from commons-lang3.
*
*
Capitalizes a String changing the first character to title case as
* per {@link Character#toTitleCase(char)}. No other characters are changed.
*
*
For a word based algorithm, see {@link org.apache.commons.lang3.text.WordUtils#capitalize(String)}.
* A {@code null} input String returns {@code null}.
*
*
* StringUtils.capitalize(null) = null
* StringUtils.capitalize("") = ""
* StringUtils.capitalize("cat") = "Cat"
* StringUtils.capitalize("cAt") = "CAt"
* StringUtils.capitalize("'cat'") = "'cat'"
*
*
* @param str the String to capitalize, may be null
* @return the capitalized String, {@code null} if null String input
* @see org.apache.commons.lang3.text.WordUtils#capitalize(String)
*/
public static String capitalize(final String str) {
int strLen;
if (str == null || (strLen = str.length()) == 0) {
return str;
}
final char firstChar = str.charAt(0);
final char newChar = Character.toTitleCase(firstChar);
if (firstChar == newChar) {
// already capitalized
return str;
}
char[] newChars = new char[strLen];
newChars[0] = newChar;
str.getChars(1, strLen, newChars, 1);
return String.valueOf(newChars);
}
/**
* Taken from commons-lang3.
* Checks if a CharSequence is whitespace, empty ("") or null.
*
*
* StringUtils.isBlank(null) = true
* StringUtils.isBlank("") = true
* StringUtils.isBlank(" ") = true
* StringUtils.isBlank("bob") = false
* StringUtils.isBlank(" bob ") = false
*
*
* @param cs the CharSequence to check, may be null
* @return {@code true} if the CharSequence is null, empty or whitespace
*/
public static boolean isBlank(final CharSequence cs) {
int strLen;
if (cs == null || (strLen = cs.length()) == 0) {
return true;
}
for (int i = 0; i < strLen; i++) {
if (Character.isWhitespace(cs.charAt(i)) == false) {
return false;
}
}
return true;
}
public static String join(Collection values, String joinToken) {
if (values == null) {
return null;
}
if (values.size() == 0) {
return "";
}
if (values.size() == 1) {
return values.iterator().next().toString();
}
if (joinToken == null) {
joinToken = "null"; // backward compat with commons-lang StringUtils...
}
StringBuilder sb = new StringBuilder(values.size() * (16 + joinToken.length()));
Iterator it = values.iterator();
sb.append(it.next());
while (it.hasNext()) {
sb.append(joinToken).append(it.next());
}
return sb.toString();
}
public static String joinArray(Object[] values, String joinToken) {
if (values == null) {
return null;
}
if (values.length == 0) {
return "";
}
if (values.length == 1) {
return values[0].toString();
}
if (joinToken == null) {
joinToken = "null"; // backward compat with commons-lang StringUtils...
}
StringBuilder sb = new StringBuilder(values.length * (16 + joinToken.length()));
sb.append(values[0]);
for (int i = 1; i < values.length; i++) {
sb.append(joinToken).append(values[i]);
}
return sb.toString();
}
/**
* Splits the provided text into an array, separator is whitespace.
*/
public static String[] split(String str) {
return split(str, null);
}
/**
*
Splits the provided text into an array, separator is whitespace.
*/
public static String[] split(String str, Character token) {
if (str == null || str.length() == 0) {
return ObjectUtils.EMPTY_STRING_ARRAY;
}
// split on token
List ret = new ArrayList();
StringBuilder sb = new StringBuilder(str.length());
for (int pos = 0; pos < str.length(); pos++) {
char c = str.charAt(pos);
if ((token == null && Character.isWhitespace(c)) || (token != null && token.equals(c))) {
if (sb.length() > 0) {
ret.add(sb.toString());
sb.setLength(0); // reset the string
}
} else {
sb.append(c);
}
}
if (sb.length() > 0) {
ret.add(sb.toString());
}
return ret.toArray(new String[ret.size()]);
}
}