java 正则表达式--group

运行结果：

group 0 :x99SuperJava

group 1 :99

group 2 :SuperJava

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另外一个例子：

?运行结果：
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public class Test {  public static void main(String args[]){  StringBuffer sb = new StringBuffer();  String replacement = "Smith";  Pattern pattern = Pattern.compile("Bond");  Matcher matcher =pattern.matcher("My name is Bond. James Bond. I would like a martini.");  matcher.find();matcher.appendReplacement(sb, replacement);// 结果是My name is Smith. James// Smithmatcher.appendTail(sb);System.out.println(sb);}   }  

?运行结果： ?My name is Smith. James Bond. I would like a martini.
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