package com.core.util;
public class StringUtil {
// Performance testing notes (JDK 1.4, Jul03, scolebourne)
// Whitespace:
// Character.isWhitespace() is faster than WHITESPACE.indexOf()
// where WHITESPACE is a string of all whitespace characters
//
// Character access:
// String.charAt(n) versus toCharArray(), then array[n]
// String.charAt(n) is about 15% worse for a 10K string
// They are about equal for a length 50 string
// String.charAt(n) is about 4 times better for a length 3 string
// String.charAt(n) is best bet overall
//
// Append:
// String.concat about twice as fast as StringBuffer.append
// (not sure who tested this)
public static final String EMPTY = "";
public static final int INDEX_NOT_FOUND = -1;
private static final int PAD_LIMIT = 8192;
public StringUtil() {
super();
}
// Empty checks
//-----------------------------------------------------------------------
public static boolean isEmpty(String str) {
return str == null || str.length() == 0;
}
public static boolean isNotEmpty(String str) {
return !StringUtil.isEmpty(str);
}
public static boolean isBlank(String str) {
int strLen;
if (str == null || (strLen = str.length()) == 0) {
return true;
}
for (int i = 0; i < strLen; i++) {
if ((Character.isWhitespace(str.charAt(i)) == false)) {
return false;
}
}
return true;
}
public static boolean isNotBlank(String str) {
return !StringUtil.isBlank(str);
}
// Trim
//-----------------------------------------------------------------------
public static String clean(String str) {
return str == null ? EMPTY : str.trim();
}
public static String trim(String str) {
return str == null ? null : str.trim();
}
public static String trimToNull(String str) {
String ts = trim(str);
return isEmpty(ts) ? null : ts;
}
public static String trimToEmpty(String str) {
return str == null ? EMPTY : str.trim();
}
// Stripping
//-----------------------------------------------------------------------
public static String strip(String str) {
return strip(str, null);
}
public static String stripToNull(String str) {
if (str == null) {
return null;
}
str = strip(str, null);
return str.length() == 0 ? null : str;
}
public static String stripToEmpty(String str) {
return str == null ? EMPTY : strip(str, null);
}
public static String strip(String str, String stripChars) {
if (isEmpty(str)) {
return str;
}
str = stripStart(str, stripChars);
return stripEnd(str, stripChars);
}
public static String stripStart(String str, String stripChars) {
int strLen;
if (str == null || (strLen = str.length()) == 0) {
return str;
}
int start = 0;
if (stripChars == null) {
while ((start != strLen) && Character.isWhitespace(str.charAt(start))) {
start++;
}
} else if (stripChars.length() == 0) {
return str;
} else {
while ((start != strLen) && (stripChars.indexOf(str.charAt(start)) != -1)) {
start++;
}
}
return str.substring(start);
}
public static String stripEnd(String str, String stripChars) {
int end;
if (str == null || (end = str.length()) == 0) {
return str;
}
if (stripChars == null) {
while ((end != 0) && Character.isWhitespace(str.charAt(end - 1))) {
end--;
}
} else if (stripChars.length() == 0) {
return str;
} else {
while ((end != 0) && (stripChars.indexOf(str.charAt(end - 1)) != -1)) {
end--;
}
}
return str.substring(0, end);
}
// StripAll
//-----------------------------------------------------------------------
public static String[] stripAll(String[] strs) {
return stripAll(strs, null);
}
public static String[] stripAll(String[] strs, String stripChars) {
int strsLen;
if (strs == null || (strsLen = strs.length) == 0) {
return strs;
}
String[] newArr = new String[strsLen];
for (int i = 0; i < strsLen; i++) {
newArr[i] = strip(strs[i], stripChars);
}
return newArr;
}
// Equals
//-----------------------------------------------------------------------
public static boolean equals(String str1, String str2) {
return str1 == null ? str2 == null : str1.equals(str2);
}
public static boolean equalsIgnoreCase(String str1, String str2) {
return str1 == null ? str2 == null : str1.equalsIgnoreCase(str2);
}
// IndexOf
//-----------------------------------------------------------------------
public static int indexOf(String str, char searchChar) {
if (isEmpty(str)) {
return -1;
}
return str.indexOf(searchChar);
}
public static int indexOf(String str, char searchChar, int startPos) {
if (isEmpty(str)) {
return -1;
}
return str.indexOf(searchChar, startPos);
}
public static int indexOf(String str, String searchStr) {
if (str == null || searchStr == null) {
return -1;
}
return str.indexOf(searchStr);
}
public static int ordinalIndexOf(String str, String searchStr, int ordinal) {
if (str == null || searchStr == null || ordinal <= 0) {
return INDEX_NOT_FOUND;
}
if (searchStr.length() == 0) {
return 0;
}
int found = 0;
int index = INDEX_NOT_FOUND;
do {
index = str.indexOf(searchStr, index + 1);
if (index < 0) {
return index;
}
found++;
} while (found < ordinal);
return index;
}
public static int indexOf(String str, String searchStr, int startPos) {
if (str == null || searchStr == null) {
return -1;
}
// JDK1.2/JDK1.3 have a bug, when startPos > str.length for "", hence
if (searchStr.length() == 0 && startPos >= str.length()) {
return str.length();
}
return str.indexOf(searchStr, startPos);
}
// LastIndexOf
//-----------------------------------------------------------------------
public static int lastIndexOf(String str, char searchChar) {
if (isEmpty(str)) {
return -1;
}
return str.lastIndexOf(searchChar);
}
public static int lastIndexOf(String str, char searchChar, int startPos) {
if (isEmpty(str)) {
return -1;
}
return str.lastIndexOf(searchChar, startPos);
}
public static int lastIndexOf(String str, String searchStr) {
if (str == null || searchStr == null) {
return -1;
}
return str.lastIndexOf(searchStr);
}
public static int lastIndexOf(String str, String searchStr, int startPos) {
if (str == null || searchStr == null) {
return -1;
}
return str.lastIndexOf(searchStr, startPos);
}
// Contains
//-----------------------------------------------------------------------
public static boolean contains(String str, char searchChar) {
if (isEmpty(str)) {
return false;
}
return str.indexOf(searchChar) >= 0;
}
public static boolean contains(String str, String searchStr) {
if (str == null || searchStr == null) {
return false;
}
return str.indexOf(searchStr) >= 0;
}
public static boolean containsIgnoreCase(String str, String searchStr) {
if (str == null || searchStr == null) {
return false;
}
return contains(str.toUpperCase(), searchStr.toUpperCase());
}
// ContainsAny
//-----------------------------------------------------------------------
public static boolean containsAny(String str, char[] searchChars) {
if (str == null || str.length() == 0 || searchChars == null || searchChars.length == 0) {
return false;
}
for (int i = 0; i < str.length(); i++) {
char ch = str.charAt(i);
for (int j = 0; j < searchChars.length; j++) {
if (searchChars[j] == ch) {
return true;
}
}
}
return false;
}
public static boolean containsAny(String str, String searchChars) {
if (searchChars == null) {
return false;
}
return containsAny(str, searchChars.toCharArray());
}
public static int indexOfAnyBut(String str, String searchChars) {
if (isEmpty(str) || isEmpty(searchChars)) {
return -1;
}
for (int i = 0; i < str.length(); i++) {
if (searchChars.indexOf(str.charAt(i)) < 0) {
return i;
}
}
return -1;
}
// ContainsNone
//-----------------------------------------------------------------------
public static boolean containsNone(String str, char[] invalidChars) {
if (str == null || invalidChars == null) {
return true;
}
int strSize = str.length();
int validSize = invalidChars.length;
for (int i = 0; i < strSize; i++) {
char ch = str.charAt(i);
for (int j = 0; j < validSize; j++) {
if (invalidChars[j] == ch) {
return false;
}
}
}
return true;
}
public static boolean containsNone(String str, String invalidChars) {
if (str == null || invalidChars == null) {
return true;
}
return containsNone(str, invalidChars.toCharArray());
}
// IndexOfAny strings
//-----------------------------------------------------------------------
public static int indexOfAny(String str, String[] searchStrs) {
if ((str == null) || (searchStrs == null)) {
return -1;
}
int sz = searchStrs.length;
// String's can't have a MAX_VALUEth index.
int ret = Integer.MAX_VALUE;
int tmp = 0;
for (int i = 0; i < sz; i++) {
String search = searchStrs[i];
if (search == null) {
continue;
}
tmp = str.indexOf(search);
if (tmp == -1) {
continue;
}
if (tmp < ret) {
ret = tmp;
}
}
return (ret == Integer.MAX_VALUE) ? -1 : ret;
}
public static int lastIndexOfAny(String str, String[] searchStrs) {
if ((str == null) || (searchStrs == null)) {
return -1;
}
int sz = searchStrs.length;
int ret = -1;
int tmp = 0;
for (int i = 0; i < sz; i++) {
String search = searchStrs[i];
if (search == null) {
continue;
}
tmp = str.lastIndexOf(search);
if (tmp > ret) {
ret = tmp;
}
}
return ret;
}
// Substring
//-----------------------------------------------------------------------
public static String substring(String str, int start) {
if (str == null) {
return null;
}
// handle negatives, which means last n characters
if (start < 0) {
start = str.length() + start; // remember start is negative
}
if (start < 0) {
start = 0;
}
if (start > str.length()) {
return EMPTY;
}
return str.substring(start);
}
public static String substring(String str, int start, int end) {
if (str == null) {
return null;
}
// handle negatives
if (end < 0) {
end = str.length() + end; // remember end is negative
}
if (start < 0) {
start = str.length() + start; // remember start is negative
}
// check length next
if (end > str.length()) {
end = str.length();
}
// if start is greater than end, return ""
if (start > end) {
return EMPTY;
}
if (start < 0) {
start = 0;
}
if (end < 0) {
end = 0;
}
return str.substring(start, end);
}
// Left/Right/Mid
//-----------------------------------------------------------------------
public static String left(String str, int len) {
if (str == null) {
return null;
}
if (len < 0) {
return EMPTY;
}
if (str.length() <= len) {
return str;
}
return str.substring(0, len);
}
public static String right(String str, int len) {
if (str == null) {
return null;
}
if (len < 0) {
return EMPTY;
}
if (str.length() <= len) {
return str;
}
return str.substring(str.length() - len);
}
public static String mid(String str, int pos, int len) {
if (str == null) {
return null;
}
if (len < 0 || pos > str.length()) {
return EMPTY;
}
if (pos < 0) {
pos = 0;
}
if (str.length() <= (pos + len)) {
return str.substring(pos);
}
return str.substring(pos, pos + len);
}
// SubStringAfter/SubStringBefore
//-----------------------------------------------------------------------
public static String substringBefore(String str, String separator) {
if (isEmpty(str) || separator == null) {
return str;
}
if (separator.length() == 0) {
return EMPTY;
}
int pos = str.indexOf(separator);
if (pos == -1) {
return str;
}
return str.substring(0, pos);
}
public static String substringAfter(String str, String separator) {
if (isEmpty(str)) {
return str;
}
if (separator == null) {
return EMPTY;
}
int pos = str.indexOf(separator);
if (pos == -1) {
return EMPTY;
}
return str.substring(pos + separator.length());
}
public static String substringBeforeLast(String str, String separator) {
if (isEmpty(str) || isEmpty(separator)) {
return str;
}
int pos = str.lastIndexOf(separator);
if (pos == -1) {
return str;
}
return str.substring(0, pos);
}
public static String substringAfterLast(String str, String separator) {
if (isEmpty(str)) {
return str;
}
if (isEmpty(separator)) {
return EMPTY;
}
int pos = str.lastIndexOf(separator);
if (pos == -1 || pos == (str.length() - separator.length())) {
return EMPTY;
}
return str.substring(pos + separator.length());
}
// Substring between
//-----------------------------------------------------------------------
public static String substringBetween(String str, String tag) {
return substringBetween(str, tag, tag);
}
public static String substringBetween(String str, String open, String close) {
if (str == null || open == null || close == null) {
return null;
}
int start = str.indexOf(open);
if (start != -1) {
int end = str.indexOf(close, start + open.length());
if (end != -1) {
return str.substring(start + open.length(), end);
}
}
return null;
}
public static String join(Object[] array) {
return join(array, null);
}
public static String join(Object[] array, char separator) {
if (array == null) {
return null;
}
return join(array, separator, 0, array.length);
}
public static String join(Object[] array, char separator, int startIndex, int endIndex) {
if (array == null) {
return null;
}
int bufSize = (endIndex - startIndex);
if (bufSize <= 0) {
return EMPTY;
}
bufSize *= ((array[startIndex] == null ? 16 : array[startIndex].toString().length()) + 1);
StringBuffer buf = new StringBuffer(bufSize);
for (int i = startIndex; i < endIndex; i++) {
if (i > startIndex) {
buf.append(separator);
}
if (array[i] != null) {
buf.append(array[i]);
}
}
return buf.toString();
}
public static String join(Object[] array, String separator) {
if (array == null) {
return null;
}
return join(array, separator, 0, array.length);
}
public static String join(Object[] array, String separator, int startIndex, int endIndex) {
if (array == null) {
return null;
}
if (separator == null) {
separator = EMPTY;
}
// endIndex - startIndex > 0: Len = NofStrings *(len(firstString) + len(separator))
// (Assuming that all Strings are roughly equally long)
int bufSize = (endIndex - startIndex);
if (bufSize <= 0) {
return EMPTY;
}
bufSize *= ((array[startIndex] == null ? 16 : array[startIndex].toString().length())
+ separator.length());
StringBuffer buf = new StringBuffer(bufSize);
for (int i = startIndex; i < endIndex; i++) {
if (i > startIndex) {
buf.append(separator);
}
if (array[i] != null) {
buf.append(array[i]);
}
}
return buf.toString();
}
public static String deleteWhitespace(String str) {
if (isEmpty(str)) {
return str;
}
int sz = str.length();
char[] chs = new char[sz];
int count = 0;
for (int i = 0; i < sz; i++) {
if (!Character.isWhitespace(str.charAt(i))) {
chs[count++] = str.charAt(i);
}
}
if (count == sz) {
return str;
}
return new String(chs, 0, count);
}
// Remove
//-----------------------------------------------------------------------
public static String removeStart(String str, String remove) {
if (isEmpty(str) || isEmpty(remove)) {
return str;
}
if (str.startsWith(remove)){
return str.substring(remove.length());
}
return str;
}
public static String removeStartIgnoreCase(String str, String remove) {
if (isEmpty(str) || isEmpty(remove)) {
return str;
}
if (startsWithIgnoreCase(str, remove)) {
return str.substring(remove.length());
}
return str;
}
public static String removeEnd(String str, String remove) {
if (isEmpty(str) || isEmpty(remove)) {
return str;
}
if (str.endsWith(remove)) {
return str.substring(0, str.length() - remove.length());
}
return str;
}
public static String removeEndIgnoreCase(String str, String remove) {
if (isEmpty(str) || isEmpty(remove)) {
return str;
}
if (endsWithIgnoreCase(str, remove)) {
return str.substring(0, str.length() - remove.length());
}
return str;
}
public static String remove(String str, String remove) {
if (isEmpty(str) || isEmpty(remove)) {
return str;
}
return replace(str, remove, EMPTY, -1);
}
public static String remove(String str, char remove) {
if (isEmpty(str) || str.indexOf(remove) == -1) {
return str;
}
char[] chars = str.toCharArray();
int pos = 0;
for (int i = 0; i < chars.length; i++) {
if (chars[i] != remove) {
chars[pos++] = chars[i];
}
}
return new String(chars, 0, pos);
}
// Replacing
//-----------------------------------------------------------------------
public static String replaceOnce(String text, String searchString, String replacement) {
return replace(text, searchString, replacement, 1);
}
public static String replace(String text, String searchString, String replacement) {
return replace(text, searchString, replacement, -1);
}
public static String replace(String text, String searchString, String replacement, int max) {
if (isEmpty(text) || isEmpty(searchString) || replacement == null || max == 0) {
return text;
}
int start = 0;
int end = text.indexOf(searchString, start);
if (end == -1) {
return text;
}
int replLength = searchString.length();
int increase = replacement.length() - replLength;
increase = (increase < 0 ? 0 : increase);
increase *= (max < 0 ? 16 : (max > 64 ? 64 : max));
StringBuffer buf = new StringBuffer(text.length() + increase);
while (end != -1) {
buf.append(text.substring(start, end)).append(replacement);
start = end + replLength;
if (--max == 0) {
break;
}
end = text.indexOf(searchString, start);
}
buf.append(text.substring(start));
return buf.toString();
}
public static String replaceEach(String text, String[] searchList, String[] replacementList) {
return replaceEach(text, searchList, replacementList, false, 0);
}
public static String replaceEachRepeatedly(String text, String[] searchList, String[] replacementList) {
// timeToLive should be 0 if not used or nothing to replace, else it's
// the length of the replace array
int timeToLive = searchList == null ? 0 : searchList.length;
return replaceEach(text, searchList, replacementList, true, timeToLive);
}
private static String replaceEach(String text, String[] searchList, String[] replacementList,
boolean repeat, int timeToLive)
{
// mchyzer Performance note: This creates very few new objects (one major goal)
// let me know if there are performance requests, we can create a harness to measure
if (text == null || text.length() == 0 || searchList == null ||
searchList.length == 0 || replacementList == null || replacementList.length == 0)
{
return text;
}
// if recursing, this shouldnt be less than 0
if (timeToLive < 0) {
throw new IllegalStateException("TimeToLive of " + timeToLive + " is less than 0: " + text);
}
int searchLength = searchList.length;
int replacementLength = replacementList.length;
// make sure lengths are ok, these need to be equal
if (searchLength != replacementLength) {
throw new IllegalArgumentException("Search and Replace array lengths don't match: "
+ searchLength
+ " vs "
+ replacementLength);
}
// keep track of which still have matches
boolean[] noMoreMatchesForReplIndex = new boolean[searchLength];
// index on index that the match was found
int textIndex = -1;
int replaceIndex = -1;
int tempIndex = -1;
// index of replace array that will replace the search string found
// NOTE: logic duplicated below START
for (int i = 0; i < searchLength; i++) {
if (noMoreMatchesForReplIndex[i] || searchList[i] == null ||
searchList[i].length() == 0 || replacementList[i] == null)
{
continue;
}
tempIndex = text.indexOf(searchList[i]);
// see if we need to keep searching for this
if (tempIndex == -1) {
noMoreMatchesForReplIndex[i] = true;
} else {
if (textIndex == -1 || tempIndex < textIndex) {
textIndex = tempIndex;
replaceIndex = i;
}
}
}
// NOTE: logic mostly below END
// no search strings found, we are done
if (textIndex == -1) {
return text;
}
int start = 0;
// get a good guess on the size of the result buffer so it doesnt have to double if it goes over a bit
int increase = 0;
// count the replacement text elements that are larger than their corresponding text being replaced
for (int i = 0; i < searchList.length; i++) {
int greater = replacementList[i].length() - searchList[i].length();
if (greater > 0) {
increase += 3 * greater; // assume 3 matches
}
}
// have upper-bound at 20% increase, then let Java take over
increase = Math.min(increase, text.length() / 5);
StringBuffer buf = new StringBuffer(text.length() + increase);
while (textIndex != -1) {
for (int i = start; i < textIndex; i++) {
buf.append(text.charAt(i));
}
buf.append(replacementList[replaceIndex]);
start = textIndex + searchList[replaceIndex].length();
textIndex = -1;
replaceIndex = -1;
tempIndex = -1;
// find the next earliest match
// NOTE: logic mostly duplicated above START
for (int i = 0; i < searchLength; i++) {
if (noMoreMatchesForReplIndex[i] || searchList[i] == null ||
searchList[i].length() == 0 || replacementList[i] == null)
{
continue;
}
tempIndex = text.indexOf(searchList[i], start);
// see if we need to keep searching for this
if (tempIndex == -1) {
noMoreMatchesForReplIndex[i] = true;
} else {
if (textIndex == -1 || tempIndex < textIndex) {
textIndex = tempIndex;
replaceIndex = i;
}
}
}
// NOTE: logic duplicated above END
}
int textLength = text.length();
for (int i = start; i < textLength; i++) {
buf.append(text.charAt(i));
}
String result = buf.toString();
if (!repeat) {
return result;
}
return replaceEach(result, searchList, replacementList, repeat, timeToLive - 1);
}
// Replace, character based
//-----------------------------------------------------------------------
public static String replaceChars(String str, char searchChar, char replaceChar) {
if (str == null) {
return null;
}
return str.replace(searchChar, replaceChar);
}
public static String replaceChars(String str, String searchChars, String replaceChars) {
if (isEmpty(str) || isEmpty(searchChars)) {
return str;
}
if (replaceChars == null) {
replaceChars = EMPTY;
}
boolean modified = false;
int replaceCharsLength = replaceChars.length();
int strLength = str.length();
StringBuffer buf = new StringBuffer(strLength);
for (int i = 0; i < strLength; i++) {
char ch = str.charAt(i);
int index = searchChars.indexOf(ch);
if (index >= 0) {
modified = true;
if (index < replaceCharsLength) {
buf.append(replaceChars.charAt(index));
}
} else {
buf.append(ch);
}
}
if (modified) {
return buf.toString();
}
return str;
}
// Overlay
//-----------------------------------------------------------------------
public static String overlayString(String text, String overlay, int start, int end) {
return new StringBuffer(start + overlay.length() + text.length() - end + 1)
.append(text.substring(0, start))
.append(overlay)
.append(text.substring(end))
.toString();
}
public static String overlay(String str, String overlay, int start, int end) {
if (str == null) {
return null;
}
if (overlay == null) {
overlay = EMPTY;
}
int len = str.length();
if (start < 0) {
start = 0;
}
if (start > len) {
start = len;
}
if (end < 0) {
end = 0;
}
if (end > len) {
end = len;
}
if (start > end) {
int temp = start;
start = end;
end = temp;
}
return new StringBuffer(len + start - end + overlay.length() + 1)
.append(str.substring(0, start))
.append(overlay)
.append(str.substring(end))
.toString();
}
public static String chomp(String str, String separator) {
if (isEmpty(str) || separator == null) {
return str;
}
if (str.endsWith(separator)) {
return str.substring(0, str.length() - separator.length());
}
return str;
}
// Padding
//-----------------------------------------------------------------------
public static String repeat(String str, int repeat) {
// Performance tuned for 2.0 (JDK1.4)
if (str == null) {
return null;
}
if (repeat <= 0) {
return EMPTY;
}
int inputLength = str.length();
if (repeat == 1 || inputLength == 0) {
return str;
}
if (inputLength == 1 && repeat <= PAD_LIMIT) {
return padding(repeat, str.charAt(0));
}
int outputLength = inputLength * repeat;
switch (inputLength) {
case 1 :
char ch = str.charAt(0);
char[] output1 = new char[outputLength];
for (int i = repeat - 1; i >= 0; i--) {
output1[i] = ch;
}
return new String(output1);
case 2 :
char ch0 = str.charAt(0);
char ch1 = str.charAt(1);
char[] output2 = new char[outputLength];
for (int i = repeat * 2 - 2; i >= 0; i--, i--) {
output2[i] = ch0;
output2[i + 1] = ch1;
}
return new String(output2);
default :
StringBuffer buf = new StringBuffer(outputLength);
for (int i = 0; i < repeat; i++) {
buf.append(str);
}
return buf.toString();
}
}
private static String padding(int repeat, char padChar) throws IndexOutOfBoundsException {
if (repeat < 0) {
throw new IndexOutOfBoundsException("Cannot pad a negative amount: " + repeat);
}
final char[] buf = new char[repeat];
for (int i = 0; i < buf.length; i++) {
buf[i] = padChar;
}
return new String(buf);
}
public static String rightPad(String str, int size) {
return rightPad(str, size, ' ');
}
public static String rightPad(String str, int size, char padChar) {
if (str == null) {
return null;
}
int pads = size - str.length();
if (pads <= 0) {
return str; // returns original String when possible
}
if (pads > PAD_LIMIT) {
return rightPad(str, size, String.valueOf(padChar));
}
return str.concat(padding(pads, padChar));
}
public static String rightPad(String str, int size, String padStr) {
if (str == null) {
return null;
}
if (isEmpty(padStr)) {
padStr = " ";
}
int padLen = padStr.length();
int strLen = str.length();
int pads = size - strLen;
if (pads <= 0) {
return str; // returns original String when possible
}
if (padLen == 1 && pads <= PAD_LIMIT) {
return rightPad(str, size, padStr.charAt(0));
}
if (pads == padLen) {
return str.concat(padStr);
} else if (pads < padLen) {
return str.concat(padStr.substring(0, pads));
} else {
char[] padding = new char[pads];
char[] padChars = padStr.toCharArray();
for (int i = 0; i < pads; i++) {
padding[i] = padChars[i % padLen];
}
return str.concat(new String(padding));
}
}
public static String leftPad(String str, int size) {
return leftPad(str, size, ' ');
}
public static String leftPad(String str, int size, char padChar) {
if (str == null) {
return null;
}
int pads = size - str.length();
if (pads <= 0) {
return str; // returns original String when possible
}
if (pads > PAD_LIMIT) {
return leftPad(str, size, String.valueOf(padChar));
}
return padding(pads, padChar).concat(str);
}
public static String leftPad(String str, int size, String padStr) {
if (str == null) {
return null;
}
if (isEmpty(padStr)) {
padStr = " ";
}
int padLen = padStr.length();
int strLen = str.length();
int pads = size - strLen;
if (pads <= 0) {
return str; // returns original String when possible
}
if (padLen == 1 && pads <= PAD_LIMIT) {
return leftPad(str, size, padStr.charAt(0));
}
if (pads == padLen) {
return padStr.concat(str);
} else if (pads < padLen) {
return padStr.substring(0, pads).concat(str);
} else {
char[] padding = new char[pads];
char[] padChars = padStr.toCharArray();
for (int i = 0; i < pads; i++) {
padding[i] = padChars[i % padLen];
}
return new String(padding).concat(str);
}
}
public static int length(String str) {
return str == null ? 0 : str.length();
}
// Centering
//-----------------------------------------------------------------------
public static String center(String str, int size) {
return center(str, size, ' ');
}
public static String center(String str, int size, char padChar) {
if (str == null || size <= 0) {
return str;
}
int strLen = str.length();
int pads = size - strLen;
if (pads <= 0) {
return str;
}
str = leftPad(str, strLen + pads / 2, padChar);
str = rightPad(str, size, padChar);
return str;
}
public static String center(String str, int size, String padStr) {
if (str == null || size <= 0) {
return str;
}
if (isEmpty(padStr)) {
padStr = " ";
}
int strLen = str.length();
int pads = size - strLen;
if (pads <= 0) {
return str;
}
str = leftPad(str, strLen + pads / 2, padStr);
str = rightPad(str, size, padStr);
return str;
}
// Case conversion
//-----------------------------------------------------------------------
public static String upperCase(String str) {
if (str == null) {
return null;
}
return str.toUpperCase();
}
public static String lowerCase(String str) {
if (str == null) {
return null;
}
return str.toLowerCase();
}
public static String capitalize(String str) {
int strLen;
if (str == null || (strLen = str.length()) == 0) {
return str;
}
return new StringBuffer(strLen)
.append(Character.toTitleCase(str.charAt(0)))
.append(str.substring(1))
.toString();
}
public static String capitalise(String str) {
return capitalize(str);
}
public static String uncapitalize(String str) {
int strLen;
if (str == null || (strLen = str.length()) == 0) {
return str;
}
return new StringBuffer(strLen)
.append(Character.toLowerCase(str.charAt(0)))
.append(str.substring(1))
.toString();
}
public static String uncapitalise(String str) {
return uncapitalize(str);
}
public static String swapCase(String str) {
int strLen;
if (str == null || (strLen = str.length()) == 0) {
return str;
}
StringBuffer buffer = new StringBuffer(strLen);
char ch = 0;
for (int i = 0; i < strLen; i++) {
ch = str.charAt(i);
if (Character.isUpperCase(ch)) {
ch = Character.toLowerCase(ch);
} else if (Character.isTitleCase(ch)) {
ch = Character.toLowerCase(ch);
} else if (Character.isLowerCase(ch)) {
ch = Character.toUpperCase(ch);
}
buffer.append(ch);
}
return buffer.toString();
}
// Count matches
//-----------------------------------------------------------------------
public static int countMatches(String str, String sub) {
if (isEmpty(str) || isEmpty(sub)) {
return 0;
}
int count = 0;
int idx = 0;
while ((idx = str.indexOf(sub, idx)) != -1) {
count++;
idx += sub.length();
}
return count;
}
// Character Tests
//-----------------------------------------------------------------------
public static boolean isAlpha(String str) {
if (str == null) {
return false;
}
int sz = str.length();
for (int i = 0; i < sz; i++) {
if (Character.isLetter(str.charAt(i)) == false) {
return false;
}
}
return true;
}
public static boolean isAlphaSpace(String str) {
if (str == null) {
return false;
}
int sz = str.length();
for (int i = 0; i < sz; i++) {
if ((Character.isLetter(str.charAt(i)) == false) && (str.charAt(i) != ' ')) {
return false;
}
}
return true;
}
public static boolean isAlphanumeric(String str) {
if (str == null) {
return false;
}
int sz = str.length();
for (int i = 0; i < sz; i++) {
if (Character.isLetterOrDigit(str.charAt(i)) == false) {
return false;
}
}
return true;
}
public static boolean isAlphanumericSpace(String str) {
if (str == null) {
return false;
}
int sz = str.length();
for (int i = 0; i < sz; i++) {
if ((Character.isLetterOrDigit(str.charAt(i)) == false) && (str.charAt(i) != ' ')) {
return false;
}
}
return true;
}
public static boolean isNumeric(String str) {
if (str == null) {
return false;
}
int sz = str.length();
for (int i = 0; i < sz; i++) {
if (Character.isDigit(str.charAt(i)) == false) {
return false;
}
}
return true;
}
public static boolean isNumericSpace(String str) {
if (str == null) {
return false;
}
int sz = str.length();
for (int i = 0; i < sz; i++) {
if ((Character.isDigit(str.charAt(i)) == false) && (str.charAt(i) != ' ')) {
return false;
}
}
return true;
}
public static boolean isWhitespace(String str) {
if (str == null) {
return false;
}
int sz = str.length();
for (int i = 0; i < sz; i++) {
if ((Character.isWhitespace(str.charAt(i)) == false)) {
return false;
}
}
return true;
}
// Defaults
//-----------------------------------------------------------------------
public static String defaultString(String str) {
return str == null ? EMPTY : str;
}
public static String defaultString(String str, String defaultStr) {
return str == null ? defaultStr : str;
}
// Reversing
//-----------------------------------------------------------------------
public static String reverse(String str) {
if (str == null) {
return null;
}
return new StringBuffer(str).reverse().toString();
}
// Abbreviating
//-----------------------------------------------------------------------
public static String abbreviate(String str, int maxWidth) {
return abbreviate(str, 0, maxWidth);
}
public static String abbreviate(String str, int offset, int maxWidth) {
if (str == null) {
return null;
}
if (maxWidth < 4) {
throw new IllegalArgumentException("Minimum abbreviation width is 4");
}
if (str.length() <= maxWidth) {
return str;
}
if (offset > str.length()) {
offset = str.length();
}
if ((str.length() - offset) < (maxWidth - 3)) {
offset = str.length() - (maxWidth - 3);
}
if (offset <= 4) {
return str.substring(0, maxWidth - 3) + "...";
}
if (maxWidth < 7) {
throw new IllegalArgumentException("Minimum abbreviation width with offset is 7");
}
if ((offset + (maxWidth - 3)) < str.length()) {
return "..." + abbreviate(str.substring(offset), maxWidth - 3);
}
return "..." + str.substring(str.length() - (maxWidth - 3));
}
// Difference
//-----------------------------------------------------------------------
public static String difference(String str1, String str2) {
if (str1 == null) {
return str2;
}
if (str2 == null) {
return str1;
}
int at = indexOfDifference(str1, str2);
if (at == -1) {
return EMPTY;
}
return str2.substring(at);
}
public static int indexOfDifference(String str1, String str2) {
if (str1 == str2) {
return -1;
}
if (str1 == null || str2 == null) {
return 0;
}
int i;
for (i = 0; i < str1.length() && i < str2.length(); ++i) {
if (str1.charAt(i) != str2.charAt(i)) {
break;
}
}
if (i < str2.length() || i < str1.length()) {
return i;
}
return -1;
}
public static int indexOfDifference(String[] strs) {
if (strs == null || strs.length <= 1) {
return -1;
}
boolean anyStringNull = false;
boolean allStringsNull = true;
int arrayLen = strs.length;
int shortestStrLen = Integer.MAX_VALUE;
int longestStrLen = 0;
// find the min and max string lengths; this avoids checking to make
// sure we are not exceeding the length of the string each time through
// the bottom loop.
for (int i = 0; i < arrayLen; i++) {
if (strs[i] == null) {
anyStringNull = true;
shortestStrLen = 0;
} else {
allStringsNull = false;
shortestStrLen = Math.min(strs[i].length(), shortestStrLen);
longestStrLen = Math.max(strs[i].length(), longestStrLen);
}
}
// handle lists containing all nulls or all empty strings
if (allStringsNull || (longestStrLen == 0 && !anyStringNull)) {
return -1;
}
// handle lists containing some nulls or some empty strings
if (shortestStrLen == 0) {
return 0;
}
// find the position with the first difference across all strings
int firstDiff = -1;
for (int stringPos = 0; stringPos < shortestStrLen; stringPos++) {
char comparisonChar = strs[0].charAt(stringPos);
for (int arrayPos = 1; arrayPos < arrayLen; arrayPos++) {
if (strs[arrayPos].charAt(stringPos) != comparisonChar) {
firstDiff = stringPos;
break;
}
}
if (firstDiff != -1) {
break;
}
}
if (firstDiff == -1 && shortestStrLen != longestStrLen) {
// we compared all of the characters up to the length of the
// shortest string and didn't find a match, but the string lengths
// vary, so return the length of the shortest string.
return shortestStrLen;
}
return firstDiff;
}
public static String getCommonPrefix(String[] strs) {
if (strs == null || strs.length == 0) {
return EMPTY;
}
int smallestIndexOfDiff = indexOfDifference(strs);
if (smallestIndexOfDiff == -1) {
// all strings were identical
if (strs[0] == null) {
return EMPTY;
}
return strs[0];
} else if (smallestIndexOfDiff == 0) {
// there were no common initial characters
return EMPTY;
} else {
// we found a common initial character sequence
return strs[0].substring(0, smallestIndexOfDiff);
}
}
// Misc
//-----------------------------------------------------------------------
public static int getLevenshteinDistance(String s, String t) {
if (s == null || t == null) {
throw new IllegalArgumentException("Strings must not be null");
}
int n = s.length(); // length of s
int m = t.length(); // length of t
if (n == 0) {
return m;
} else if (m == 0) {
return n;
}
if (n > m) {
// swap the input strings to consume less memory
String tmp = s;
s = t;
t = tmp;
n = m;
m = t.length();
}
int p[] = new int[n+1]; //'previous' cost array, horizontally
int d[] = new int[n+1]; // cost array, horizontally
int _d[]; //placeholder to assist in swapping p and d
// indexes into strings s and t
int i; // iterates through s
int j; // iterates through t
char t_j; // jth character of t
int cost; // cost
for (i = 0; i<=n; i++) {
p[i] = i;
}
for (j = 1; j<=m; j++) {
t_j = t.charAt(j-1);
d[0] = j;
for (i=1; i<=n; i++) {
cost = s.charAt(i-1)==t_j ? 0 : 1;
// minimum of cell to the left+1, to the top+1, diagonally left and up +cost
d[i] = Math.min(Math.min(d[i-1]+1, p[i]+1), p[i-1]+cost);
}
// copy current distance counts to 'previous row' distance counts
_d = p;
p = d;
d = _d;
}
// our last action in the above loop was to switch d and p, so p now
// actually has the most recent cost counts
return p[n];
}
// startsWith
//-----------------------------------------------------------------------
public static boolean startsWith(String str, String prefix) {
return startsWith(str, prefix, false);
}
public static boolean startsWithIgnoreCase(String str, String prefix) {
return startsWith(str, prefix, true);
}
private static boolean startsWith(String str, String prefix, boolean ignoreCase) {
if (str == null || prefix == null) {
return (str == null && prefix == null);
}
if (prefix.length() > str.length()) {
return false;
}
return str.regionMatches(ignoreCase, 0, prefix, 0, prefix.length());
}
// endsWith
//-----------------------------------------------------------------------
public static boolean endsWith(String str, String suffix) {
return endsWith(str, suffix, false);
}
public static boolean endsWithIgnoreCase(String str, String suffix) {
return endsWith(str, suffix, true);
}
private static boolean endsWith(String str, String suffix, boolean ignoreCase) {
if (str == null || suffix == null) {
return (str == null && suffix == null);
}
if (suffix.length() > str.length()) {
return false;
}
int strOffset = str.length() - suffix.length();
return str.regionMatches(ignoreCase, strOffset, suffix, 0, suffix.length());
}
}
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