import java.util.regex.Matcher;

import java.util.regex.Pattern;

/**

 * Created by Frank

 * 替换匹配的文本

 */

public class ReplaceDemo {

    public static void main(String[] args) {

        // 创建一个正则表达式模式，用以匹配一个单词（\b=单词边界）

        String patt = "\\bfavor\\b";

        // 用于测试的输入字符串

        String input = "Do me a favor? Fetch my favorites.AAA favor BBB";

        System.out.println("Input:" + input);

        // 从正则表达式实例中运行方法并查看其如何运行

        Pattern r = Pattern.compile(patt);

        Matcher m = r.matcher(input);

        System.out.println("ReplaceAll:" + m.replaceAll("favour"));

        // appendReplacement方法

        m.reset();

        StringBuffer sb = new StringBuffer();

        while (m.find()) {

            // 将匹配之前的字符串复制到sb,再将匹配结果替换为："favour"，并追加到sb

            m.appendReplacement(sb, "favour");

        }

        System.out.println(sb.toString());

        m.appendTail(sb);

        System.out.println(sb.toString());

    }

}

Input:Do me a favor? Fetch my favorites.AAA favor BBB

ReplaceAll:Do me a favour? Fetch my favorites.AAA favour BBB

Do me a favour? Fetch my favorites.AAA favour

Do me a favour? Fetch my favorites.AAA favour BBB