Here you can find the source of splitWorker(final String str, final char separatorChar, final boolean preserveAllTokens)
Parameter | Description |
---|---|
str | the String to parse, may be null |
separatorChar | the separate character |
preserveAllTokens | if true , adjacent separators are treated as empty token separators; if false , adjacent separators are treated as one separator. |
private static String[] splitWorker(final String str, final char separatorChar, final boolean preserveAllTokens)
//package com.java2s; //License from project: Apache License import java.util.*; public class Main { /**/* www .j a va2 s .co m*/ * An empty immutable {@code String} array. */ public static final String[] EMPTY_STRING_ARRAY = new String[0]; /** * Performs the logic for the {@code split} and * {@code splitPreserveAllTokens} methods that do not return a maximum array * length. * * @param str the String to parse, may be {@code null} * @param separatorChar the separate character * @param preserveAllTokens if {@code true}, adjacent separators are treated as empty * token separators; if {@code false}, adjacent separators are * treated as one separator. * @return an array of parsed Strings, {@code null} if null String input */ private static String[] splitWorker(final String str, final char separatorChar, final boolean preserveAllTokens) { // Performance tuned for 2.0 (JDK1.4) if (str == null) { return null; } final int len = str.length(); if (len == 0) { return EMPTY_STRING_ARRAY; } final List<String> list = new ArrayList<String>(); int i = 0, start = 0; boolean match = false; boolean lastMatch = false; while (i < len) { if (str.charAt(i) == separatorChar) { if (match || preserveAllTokens) { list.add(str.substring(start, i)); match = false; lastMatch = true; } start = ++i; continue; } lastMatch = false; match = true; i++; } if (match || preserveAllTokens && lastMatch) { list.add(str.substring(start, i)); } return list.toArray(new String[list.size()]); } /** * Performs the logic for the {@code split} and * {@code splitPreserveAllTokens} methods that return a maximum array * length. * * @param str the String to parse, may be {@code null} * @param separatorChars the separate character * @param max the maximum number of elements to include in the array. A zero * or negative value implies no limit. * @param preserveAllTokens if {@code true}, adjacent separators are treated as empty * token separators; if {@code false}, adjacent separators are * treated as one separator. * @return an array of parsed Strings, {@code null} if null String input */ private static String[] splitWorker(final String str, final String separatorChars, final int max, final boolean preserveAllTokens) { // Performance tuned for 2.0 (JDK1.4) // Direct code is quicker than StringTokenizer. // Also, StringTokenizer uses isSpace() not isWhitespace() if (str == null) { return null; } final int len = str.length(); if (len == 0) { return EMPTY_STRING_ARRAY; } final List<String> list = new ArrayList<String>(); int sizePlus1 = 1; int i = 0, start = 0; boolean match = false; boolean lastMatch = false; if (separatorChars == null) { // Null separator means use whitespace while (i < len) { if (Character.isWhitespace(str.charAt(i))) { if (match || preserveAllTokens) { lastMatch = true; if (sizePlus1++ == max) { i = len; lastMatch = false; } list.add(str.substring(start, i)); match = false; } start = ++i; continue; } lastMatch = false; match = true; i++; } } else if (separatorChars.length() == 1) { // Optimise 1 character case final char sep = separatorChars.charAt(0); while (i < len) { if (str.charAt(i) == sep) { if (match || preserveAllTokens) { lastMatch = true; if (sizePlus1++ == max) { i = len; lastMatch = false; } list.add(str.substring(start, i)); match = false; } start = ++i; continue; } lastMatch = false; match = true; i++; } } else { // standard case while (i < len) { if (separatorChars.indexOf(str.charAt(i)) >= 0) { if (match || preserveAllTokens) { lastMatch = true; if (sizePlus1++ == max) { i = len; lastMatch = false; } list.add(str.substring(start, i)); match = false; } start = ++i; continue; } lastMatch = false; match = true; i++; } } if (match || preserveAllTokens && lastMatch) { list.add(str.substring(start, i)); } return list.toArray(new String[list.size()]); } public static String[] toArray(List<String> array) { return array.toArray(new String[] {}); } }