Java比较两个文本差异,想用java找到两个文本文件之间的内容差异

I have two text files,

a.txt

b.txt

Each text files contains some file paths. b.txt contains some more file paths than a.txt. I would like to determine which paths are added and which are removed from a.txt so that it corresponds to paths in b.txt.

For example,

abc.txt contains

E:\Users\Documents\hello\a.properties

E:\Users\Documents\hello\b.properties

E:\Users\Documents\hello\c.properties

and xyz.txt contains

E:\Users\Documents\hello\a.properties

E:\Users\Documents\hello\c.properties

E:\Users\Documents\hello\g.properties

E:\Users\Documents\hello\h.properties

Now how to find that g.prop and h.prop are added and b.prop is removed?

Could anyone explain how it is done? I could only find how to check for identical contents.

解决方案

The below code will serve your purpose irrespective of the content of the file.

import java.io.BufferedReader;

import java.io.FileNotFoundException;

import java.io.FileReader;

import java.io.InputStream;

import java.io.InputStreamReader;

import java.util.ArrayList;

import java.util.List;

public class Test {

public Test(){

System.out.println("Test.Test()");

}

public static void main(String[] args) throws Exception {

BufferedReader br1 = null;

BufferedReader br2 = null;

String sCurrentLine;

List list1 = new ArrayList();

List list2 = new ArrayList();

br1 = new BufferedReader(new FileReader("test.txt"));

br2 = new BufferedReader(new FileReader("test2.txt"));

while ((sCurrentLine = br1.readLine()) != null) {

list1.add(sCurrentLine);

}

while ((sCurrentLine = br2.readLine()) != null) {

list2.add(sCurrentLine);

}

List tmpList = new ArrayList(list1);

tmpList.removeAll(list2);

System.out.println("content from test.txt which is not there in test2.txt");

for(int i=0;i

System.out.println(tmpList.get(i)); //content from test.txt which is not there in test2.txt

}

System.out.println("content from test2.txt which is not there in test.txt");

tmpList = list2;

tmpList.removeAll(list1);

for(int i=0;i

System.out.println(tmpList.get(i)); //content from test2.txt which is not there in test.txt

}

}

}