Java String Split by Char splitString(final String s, final char c, final boolean trimBlanks)

Description

Optimized version of String#split that doesn't use regexps.

License

Apache License

Parameter

Parameter	Description
s	The string to split.
c	The separator to use to split the string.
trimBlanks	true to not return any whitespace only array items

Return

A non-null, non-empty array. <p>Copied from <a href="http://opentsdb.net">OpenTSDB</a>.

Declaration

public static String[] splitString(final String s, final char c, final boolean trimBlanks) 

Method Source Code

//package com.java2s;
/*/* ww w.ja  v a2s.c  o  m*/
 * Copyright 2015 the original author or authors.
 *
 * Licensed 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.
 */

import java.util.ArrayList;
import java.util.List;

public class Main {
    /**
     * Optimized version of {@code String#split} that doesn't use regexps.
     * This function works in O(5n) where n is the length of the string to
     * split.
     * @param s The string to split.
     * @param c The separator to use to split the string.
     * @param trimBlanks true to not return any whitespace only array items
     * @return A non-null, non-empty array.
     * <p>Copied from <a href="http://opentsdb.net">OpenTSDB</a>.
     */
    public static String[] splitString(final String s, final char c, final boolean trimBlanks) {
        final char[] chars = s.toCharArray();
        int num_substrings = 1;
        final int last = chars.length - 1;
        for (int i = 0; i <= last; i++) {
            char x = chars[i];
            if (x == c) {
                num_substrings++;
            }
        }
        final String[] result = new String[num_substrings];
        final int len = chars.length;
        int start = 0; // starting index in chars of the current substring.
        int pos = 0; // current index in chars.
        int i = 0; // number of the current substring.
        for (; pos < len; pos++) {
            if (chars[pos] == c) {
                result[i++] = new String(chars, start, pos - start);
                start = pos + 1;
            }
        }
        result[i] = new String(chars, start, pos - start);
        if (trimBlanks) {
            int blanks = 0;
            final List<String> strs = new ArrayList<String>(result.length);
            for (int x = 0; x < result.length; x++) {
                if (result[x].trim().isEmpty()) {
                    blanks++;
                } else {
                    strs.add(result[x]);
                }
            }
            if (blanks == 0)
                return result;
            return strs.toArray(new String[result.length - blanks]);
        }
        return result;
    }
}

Related

1. splitList(String source, char useChar)
2. splitOnChar(String str, char c)
3. splitOnChar(String str, int ch)
4. splitOnCharArray(String value, String splitOn)
5. SplitSearchString(String search_string, char split_char, boolean clear_exact_match_char)
6. splitString(String str, char sep)
7. splitString(String string, char ch)
8. splitStringToChars(String str)
9. splitTrim(String str, String limitChar)