com.flyfish.oauth.utils.SpringStringUtils Maven / Gradle / Ivy
package com.flyfish.oauth.utils;
import java.util.*;
public class SpringStringUtils {
/**
* Split a {@code String} at the first occurrence of the delimiter.
* Does not include the delimiter in the result.
* @param toSplit the string to split (potentially {@code null} or empty)
* @param delimiter to split the string up with (potentially {@code null} or empty)
* @return a two element array with index 0 being before the delimiter, and
* index 1 being after the delimiter (neither element includes the delimiter);
* or {@code null} if the delimiter wasn't found in the given input {@code String}
*/
public static String[] split(String toSplit, String delimiter) {
if (!hasLength(toSplit) || !hasLength(delimiter)) {
return null;
}
int offset = toSplit.indexOf(delimiter);
if (offset < 0) {
return null;
}
String beforeDelimiter = toSplit.substring(0, offset);
String afterDelimiter = toSplit.substring(offset + delimiter.length());
return new String[] {beforeDelimiter, afterDelimiter};
}
/**
* Check whether the given {@code CharSequence} contains actual text.
* More specifically, this method returns {@code true} if the
* {@code CharSequence} is not {@code null}, its length is greater than
* 0, and it contains at least one non-whitespace character.
*
* StringUtils.hasText(null) = false
* StringUtils.hasText("") = false
* StringUtils.hasText(" ") = false
* StringUtils.hasText("12345") = true
* StringUtils.hasText(" 12345 ") = true
*
* @param str the {@code CharSequence} to check (may be {@code null})
* @return {@code true} if the {@code CharSequence} is not {@code null},
* its length is greater than 0, and it does not contain whitespace only
* @see Character#isWhitespace
*/
public static boolean hasText(CharSequence str) {
return (str != null && str.length() > 0 && containsText(str));
}
/**
* Check whether the given {@code String} contains actual text.
* More specifically, this method returns {@code true} if the
* {@code String} is not {@code null}, its length is greater than 0,
* and it contains at least one non-whitespace character.
* @param str the {@code String} to check (may be {@code null})
* @return {@code true} if the {@code String} is not {@code null}, its
* length is greater than 0, and it does not contain whitespace only
* @see #hasText(CharSequence)
*/
public static boolean hasText( String str) {
return (str != null && !str.isEmpty() && containsText(str));
}
private static boolean containsText(CharSequence str) {
int strLen = str.length();
for (int i = 0; i < strLen; i++) {
if (!Character.isWhitespace(str.charAt(i))) {
return true;
}
}
return false;
}
/**
* Check that the given {@code CharSequence} is neither {@code null} nor
* of length 0.
*
Note: this method returns {@code true} for a {@code CharSequence}
* that purely consists of whitespace.
*
* StringUtils.hasLength(null) = false
* StringUtils.hasLength("") = false
* StringUtils.hasLength(" ") = true
* StringUtils.hasLength("Hello") = true
*
* @param str the {@code CharSequence} to check (may be {@code null})
* @return {@code true} if the {@code CharSequence} is not {@code null} and has length
* @see #hasText(String)
*/
public static boolean hasLength(CharSequence str) {
return (str != null && str.length() > 0);
}
/**
* Check that the given {@code String} is neither {@code null} nor of length 0.
* Note: this method returns {@code true} for a {@code String} that
* purely consists of whitespace.
* @param str the {@code String} to check (may be {@code null})
* @return {@code true} if the {@code String} is not {@code null} and has length
* @see #hasLength(CharSequence)
* @see #hasText(String)
*/
public static boolean hasLength( String str) {
return (str != null && !str.isEmpty());
}
/**
* Copy the given {@code Collection} into a {@code String} array.
*
The {@code Collection} must contain {@code String} elements only.
* @param collection the {@code Collection} to copy
* @return the {@code String} array
*/
public static String[] toStringArray(Collection collection) {
return collection.toArray(new String[0]);
}
/**
* Copy the given Enumeration into a {@code String} array.
* The Enumeration must contain {@code String} elements only.
* @param enumeration the Enumeration to copy
* @return the {@code String} array
*/
public static String[] toStringArray(Enumeration enumeration) {
return toStringArray(Collections.list(enumeration));
}
/**
* Take a {@code String} that is a delimited list and convert it into a
* {@code String} array.
* A single {@code delimiter} may consist of more than one character,
* but it will still be considered as a single delimiter string, rather
* than as bunch of potential delimiter characters, in contrast to
* {@link #tokenizeToStringArray}.
* @param str the input {@code String} (potentially {@code null} or empty)
* @param delimiter the delimiter between elements (this is a single delimiter,
* rather than a bunch individual delimiter characters)
* @return an array of the tokens in the list
* @see #tokenizeToStringArray
*/
public static String[] delimitedListToStringArray(String str, String delimiter) {
return delimitedListToStringArray(str, delimiter, null);
}
/**
* Take a {@code String} that is a delimited list and convert it into
* a {@code String} array.
*
A single {@code delimiter} may consist of more than one character,
* but it will still be considered as a single delimiter string, rather
* than as bunch of potential delimiter characters, in contrast to
* {@link #tokenizeToStringArray}.
* @param str the input {@code String} (potentially {@code null} or empty)
* @param delimiter the delimiter between elements (this is a single delimiter,
* rather than a bunch individual delimiter characters)
* @param charsToDelete a set of characters to delete; useful for deleting unwanted
* line breaks: e.g. "\r\n\f" will delete all new lines and line feeds in a {@code String}
* @return an array of the tokens in the list
* @see #tokenizeToStringArray
*/
public static String[] delimitedListToStringArray(
String str, String delimiter, String charsToDelete) {
if (str == null) {
return new String[0];
}
if (delimiter == null) {
return new String[] {str};
}
List result = new ArrayList<>();
if ("".equals(delimiter)) {
for (int i = 0; i < str.length(); i++) {
result.add(deleteAny(str.substring(i, i + 1), charsToDelete));
}
}
else {
int pos = 0;
int delPos;
while ((delPos = str.indexOf(delimiter, pos)) != -1) {
result.add(deleteAny(str.substring(pos, delPos), charsToDelete));
pos = delPos + delimiter.length();
}
if (str.length() > 0 && pos <= str.length()) {
// Add rest of String, but not in case of empty input.
result.add(deleteAny(str.substring(pos), charsToDelete));
}
}
return toStringArray(result);
}
/**
* Delete any character in a given {@code String}.
* @param inString the original {@code String}
* @param charsToDelete a set of characters to delete.
* E.g. "az\n" will delete 'a's, 'z's and new lines.
* @return the resulting {@code String}
*/
public static String deleteAny(String inString, String charsToDelete) {
if (!hasLength(inString) || !hasLength(charsToDelete)) {
return inString;
}
StringBuilder sb = new StringBuilder(inString.length());
for (int i = 0; i < inString.length(); i++) {
char c = inString.charAt(i);
if (charsToDelete.indexOf(c) == -1) {
sb.append(c);
}
}
return sb.toString();
}
/**
* Tokenize the given {@code String} into a {@code String} array via a
* {@link StringTokenizer}.
* The given {@code delimiters} string can consist of any number of
* delimiter characters. Each of those characters can be used to separate
* tokens. A delimiter is always a single character; for multi-character
* delimiters, consider using {@link #delimitedListToStringArray}.
* @param str the {@code String} to tokenize (potentially {@code null} or empty)
* @param delimiters the delimiter characters, assembled as a {@code String}
* (each of the characters is individually considered as a delimiter)
* @param trimTokens trim the tokens via {@link String#trim()}
* @param ignoreEmptyTokens omit empty tokens from the result array
* (only applies to tokens that are empty after trimming; StringTokenizer
* will not consider subsequent delimiters as token in the first place).
* @return an array of the tokens
* @see java.util.StringTokenizer
* @see String#trim()
* @see #delimitedListToStringArray
*/
public static String[] tokenizeToStringArray(
String str, String delimiters, boolean trimTokens, boolean ignoreEmptyTokens) {
if (str == null) {
return new String[0];
}
StringTokenizer st = new StringTokenizer(str, delimiters);
List tokens = new ArrayList<>();
while (st.hasMoreTokens()) {
String token = st.nextToken();
if (trimTokens) {
token = token.trim();
}
if (!ignoreEmptyTokens || token.length() > 0) {
tokens.add(token);
}
}
return toStringArray(tokens);
}
/**
* Take an array of strings and split each element based on the given delimiter.
* A {@code Properties} instance is then generated, with the left of the delimiter
* providing the key, and the right of the delimiter providing the value.
* Will trim both the key and value before adding them to the {@code Properties}.
* @param array the array to process
* @param delimiter to split each element using (typically the equals symbol)
* @return a {@code Properties} instance representing the array contents,
* or {@code null} if the array to process was {@code null} or empty
*/
public static Properties splitArrayElementsIntoProperties(String[] array, String delimiter) {
return splitArrayElementsIntoProperties(array, delimiter, null);
}
/**
* Take an array of strings and split each element based on the given delimiter.
* A {@code Properties} instance is then generated, with the left of the
* delimiter providing the key, and the right of the delimiter providing the value.
*
Will trim both the key and value before adding them to the
* {@code Properties} instance.
* @param array the array to process
* @param delimiter to split each element using (typically the equals symbol)
* @param charsToDelete one or more characters to remove from each element
* prior to attempting the split operation (typically the quotation mark
* symbol), or {@code null} if no removal should occur
* @return a {@code Properties} instance representing the array contents,
* or {@code null} if the array to process was {@code null} or empty
*/
public static Properties splitArrayElementsIntoProperties(
String[] array, String delimiter, String charsToDelete) {
if (array == null || array.length == 0) {
return null;
}
Properties result = new Properties();
for (String element : array) {
if (charsToDelete != null) {
element = deleteAny(element, charsToDelete);
}
String[] splittedElement = split(element, delimiter);
if (splittedElement == null) {
continue;
}
result.setProperty(splittedElement[0].trim(), splittedElement[1].trim());
}
return result;
}
}