Commons Lang StringUtils.replace性能vs String.replace

Commons Lang StringUtils.replace性能vs String.replace

从1的源代码中：

java.lang.String

public String replace(CharSequence target, CharSequence replacement) {   return Pattern .compile(target.toString(), Pattern.LITERAL) .matcher(this ) .replaceAll(         Matcher.quoteReplacement(replacement.toString()));}

String.replace(CharSequence target, CharSequencereplacement)

与实施

java.util.regex.Pattern

，因此，它是不奇怪的是较慢的是2，这是与实现和。

StringUtils.replace(Stringtext, String searchString, Stringreplacement)

indexOf``StringBuffer

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();}

脚注

1我链接到并复制源代码的版本是JDK 7

2我链接到并从中复制源代码的版本是common-lang-2.5