正则 替换

private static void getStrings() {
		        String str = "zz.getSszbhgbQms()+z.getZbgjQms()+z.getJkcgQms()+z.getYygjQms()";
		        String str2 ;
		        Pattern p = Pattern.compile("([a-z]+)(\\.)(get)([a-zA-Z]+)\\(\\)");
		        Matcher m = p.matcher(str);
		        ArrayList<String> strs = new ArrayList<String>();
		        while (m.find()) {
		            strs.add(m.group());
		            str = str.replace(m.group(),m.group()+"==null?0:"+m.group());
		        } 
		        System.out.println(str);
		        System.out.println("getString##");
		        for (String s : strs){
		            System.out.println(s);
		        }        
		    }

可实现功能：

将

zz.getSszbhgbQms()+z.getZbgjQms()+z.getJkcgQms()+z.getYygjQms()

转换为

zz.getSszbhgbQms()==null?0:zz.getSszbhgbQms()+z.getZbgjQms()==null?0:z.getZbgjQms()+z.getJkcgQms()==null?0:z.getJkcgQms()+z.getYygjQms()==null?0:z.getYygjQms()

为了解决get方法中有些值是null而不能相加。只能先出此下策了。

加上读入文件的io

package com.iss;

import java.io.BufferedReader;
import java.io.File;
import java.io.FileInputStream;
import java.io.FileNotFoundException;
import java.io.IOException;
import java.io.InputStreamReader;
import java.io.UnsupportedEncodingException;
import java.util.ArrayList;
import java.util.Scanner;
import java.util.regex.Matcher;
import java.util.regex.Pattern;
   
/** 
 * Scanner的小例子，从文件中读内容 
 * */  
public class Help{  
    public static void main(String[] args) throws IOException{  
        File file = new File("F:"+File.separator+"Work"+File.separator+"A.txt");  
        FileInputStream fip = new FileInputStream(file);
        
        InputStreamReader isr = new InputStreamReader(fip,"UTF-8");
        BufferedReader br = new BufferedReader(isr);
          String temp;
	        while((temp = br.readLine()) != null){
	         
	        Pattern p = Pattern.compile("([a-z]+)(\\.)(get)([a-zA-Z]+)\\(\\)");
	        Matcher m = p.matcher(temp);
	        ArrayList<String> strs = new ArrayList<String>();
	        while (m.find()) {
	            strs.add(m.group());
	            temp = temp.replace(m.group(),m.group()+"==null?0.0:"+m.group());
	        } 
	        //res +=temp;
	        System.out.println(temp);
	        }
	        //System.out.println(res);
	        br.close();
	        isr.close();
          
    }  
}

原文地址：https://www.jb51.cc/regex/361492.html