Splits a String by Character type as returned by
* java.lang.Character.getType(char)
. Groups of contiguous
* characters of the same type are returned as complete tokens.
*
* StringUtils.splitByCharacterType(null) = null * StringUtils.splitByCharacterType("") = [] * StringUtils.splitByCharacterType("ab de fg") = ["ab", " ", "de", " ", "fg"] * StringUtils.splitByCharacterType("ab de fg") = ["ab", " ", "de", " ", "fg"] * StringUtils.splitByCharacterType("ab:cd:ef") = ["ab", ":", "cd", ":", "ef"] * StringUtils.splitByCharacterType("number5") = ["number", "5"] * StringUtils.splitByCharacterType("fooBar") = ["foo", "B", "ar"] * StringUtils.splitByCharacterType("foo200Bar") = ["foo", "200", "B", "ar"] * StringUtils.splitByCharacterType("ASFRules") = ["ASFR", "ules"] ** @param str the String to split, may be
null
* @return an array of parsed Strings, null
if null String input
* @since 2.4
*/
public static String[] splitByCharacterType(String str) {
return splitByCharacterType(str, false);
}
/**
*
* Splits a String by Character type as returned by
* java.lang.Character.getType(char)
. Groups of contiguous
* characters of the same type are returned as complete tokens, with the
* following exception: if camelCase
is true
,
* the character of type Character.UPPERCASE_LETTER
, if any,
* immediately preceding a token of type
* Character.LOWERCASE_LETTER
will belong to the following
* token rather than to the preceding, if any,
* Character.UPPERCASE_LETTER
token.
*
* @param str
* the String to split, may be null
* @param camelCase
* whether to use so-called "camel-case" for letter types
* @return an array of parsed Strings, null
if null String
* input
* @since 2.4
*/
private static String[] splitByCharacterType(String str, boolean camelCase) {
if (str == null) {
return null;
}
if (str.length() == 0) {
return new String[0];
}
char[] c = str.toCharArray();
List list = new ArrayList();
int tokenStart = 0;
int currentType = Character.getType(c[tokenStart]);
for (int pos = tokenStart + 1; pos < c.length; pos++) {
int type = Character.getType(c[pos]);
if (type == currentType) {
continue;
}
if (camelCase && type == Character.LOWERCASE_LETTER
&& currentType == Character.UPPERCASE_LETTER) {
int newTokenStart = pos - 1;
if (newTokenStart != tokenStart) {
list.add(new String(c, tokenStart, newTokenStart - tokenStart));
tokenStart = newTokenStart;
}
} else {
list.add(new String(c, tokenStart, pos - tokenStart));
tokenStart = pos;
}
currentType = type;
}
list.add(new String(c, tokenStart, c.length - tokenStart));
return (String[]) list.toArray(new String[list.size()]);
}
}