java使用正則表達式的方法從json串兒，取想要的value值

例子1：

現有json：

({"code":"200","json":["111"],"message":"true"})

從中提取json的value數據。

直接上代碼如下：

import java.util.ArrayList;
import java.util.regex.Matcher;
import java.util.regex.Pattern;

public class Snippet {
    public static void main(String[] args) {
        ArrayList json = new ArrayList();
        json.add("111");
        User user = new User();
        user.setJson(json);
        user.setCode("200");
        user.setMessage("true");
        String string = "(" + JSON.toJSONString(user) + ")";
        // String regex = "\"json\":(.*?),\"message\"";// 使用非貪婪模式！
        Pattern pattern = Pattern.compile("\\[\"(.*?)\"\\]");
        Matcher matcher = pattern.matcher(string);
        while (matcher.find()) {
            System.out.println(matcher.group(1));
        }
    }
}

例子2：

String str = "我是[001]真心求救的[002]，你能幫幫我嗎";

        Pattern pattern = Pattern.compile("\\[(.*?)\\]");

        Matcher matcher = pattern.matcher(str);

        while(matcher.find()){

            System.out.println(matcher.group(1));

        }

例子3：

public static void main(String[] args) {


String
parse="[{CSTM_NO:\"11118\",CSTM_NAME:\"廣東XX電力有限公司\",FIX_GNL:\"111810158\",FIX_ACC:\"D201306070003\",OP_FLAG:\"正常\",BUSS_KIND_NAME:\"三個月定期存款\",BAL:\"25,178,750.00\",AVAL_BAL:\"25,178,750.00\",OP_DATE:\"2013-06-07\",DUE_DATE:\"2013-12-07\",ROWNUM_:1,idx:0},{CSTM_NO:\"11118\",CSTM_NAME:\"廣東XX電力有限公司\",FIX_GNL:\"111810158\",FIX_ACC:\"D201306070002\",OP_FLAG:\"正常\",BUSS_KIND_NAME:\"三個月定期存款\",BAL:\"25,178,750.00\",AVAL_BAL:\"25,178,750.00\",OP_DATE:\"2013-06-07\",DUE_DATE:\"2013-12-07\",ROWNUM_:3,idx:2},{CSTM_NO:\"11118\",CSTM_NAME:\"廣東XX電力有限公司\",FIX_GNL:\"111810158\",FIX_ACC:\"D201306070005\",OP_FLAG:\"正常\",BUSS_KIND_NAME:\"三個月定期存款\",BAL:\"25,178,750.00\",AVAL_BAL:\"25,178,750.00\",OP_DATE:\"2013-06-07\",DUE_DATE:\"2013-12-07\",ROWNUM_:4,idx:3}]";


String regex="FIX_ACC:(.*?),OP_FLAG";//別忘了使用非貪婪模式！


Matcher matcher=Pattern.compile(regex).matcher(parse);


while(matcher.find())


{


 String ret=matcher.group(1);


  System.out.println(ret);


}


}

總結：(.*?)這個拿出來，左邊括號左邊是左邊界，右邊括號右邊是右邊界，選對后直接匹配，即可拿到