对两个文件进行比较并显示异同之开源解决(显示增加删除)

 

这两个文件并不是一个字段都不同.所以用一个一个 对比的办法是不可能的.因为text2 只是在 text1的基础上

 

在首字母上面增加了一个0 其他的没有改变...由于项目紧..没有自己实现..(自己实现也没有什么太好的思路)

 

这里就不讨论原理了..

http://www.incava.org/projects/java/java-diff/

 

文件下载

 

这个是开源的解决方案..在网络上面找到的.分享下.

 

实现很简单一共有两个类..两jar包都没有..直接把源文件放到工程下面进行测试..

 

demo也是很简单的.

 

Object[] a = new Object[] {

 "a",

 "b",

 "c",

 "d",

 Object[] b = new Object[] {

 "a",

 "x",

 "y",

 "b",

 "c",

 "j",

 "e",

 Difference[] expected = new Difference[] {

 new Difference(1, -1, 1, 2),

 new Difference(3, 3, 5, 5),

 Diff diff = new Diff(a, b);

 List diffOut = diff.diff();

要求输入的是一个Object[] 或是一个Collection的接口...

 

这个就不说你是怎么将你的文件转换成数组了.

 

 String strs = "123456";

 char[] strChars = strs.toCharArray();

 Object[] objs = new Object[strChars.length];

 for( int i = 0; i strChars.length; i ++){

 objs[i] = strChars[i];

 }

 下面看这个代码:

 

 public static void main(String[] args) {

 Object[] a = new Object[] { "a", "b", "c", "d", "e" };

 Object[] b = new Object[] { "a", "x", "y", "b", "c", "j", "e", };

 Diff diff = new Diff(a, b);

 List diffOut = diff.diff();

 for (int i = 0; i diffOut.size(); i++) {

 Difference diffce = (Difference) diffOut.get(i);

 System.out.println(diffce);

 }

 在main函数里面运行:

 

显示结果:

del: [1,-1] add: [1,2]
del: [3,3] add: [5,5]

 

其中difference是显示不同的类下面有4个属性:

 

/**

 * The point at which the deletion starts.

 private int delStart = NONE;

 * The point at which the deletion ends.

 private int delEnd = NONE;

 * The point at which the addition starts.

 private int addStart = NONE;

 * The point at which the addition ends.

 private int addEnd = NONE;

 当delEnd 或 addEnd 为 -1 的时候表示不进行操作.

 

 

 //abcde

 //01234

 //a add xy /add cde

 //0 12 345

 //a add xy /add c del d /del e

 //0 12 3 4

 //a add xy /add bc del d /del add j /add e

 //0 12 34 5 6

图示: add 表示增加 del 表示删除.

del: [1,-1]  没有删除 add: [1,2]向a [1]中添加[1][2]
del: [3,3]  删除a中[3]  add: [5,5] 向a中添加[5]

 

[start,end]表示操作的数组下标从0开始.起始结束.

 

注:进行了del操作.数组长度减少.添加数组长度增加.

 

其中你自己调用.delStart,delEnd , addStart,addEnd就可以对数组进行标示了....

 

如果代码中的 add 换成其他的 b 标签就可以在html中.显示文件的不同了.

 

public static void main(String[] args) {

 Object[] a = new Object[] { "a", "b", "c", "d", "e" };

 Object[] b = new Object[] { "a", "x", "y", "b", "c", "j", "e" };

 Diff diff = new Diff(a, b);

 List diffOut = diff.diff();

 for (int i = 0; i diffOut.size(); i++) {

 Difference diffce = (Difference) diffOut.get(i);

 System.out.println(diffce);

 // abcde

 // 01234

 // a add xy /add cde

 // 0 12 345

 // a add xy /add c del d /del e

 // 0 12 3 4

 // a add xy /add bc del d /del add j /add e

 // 0 12 34 5 6

 ArrayList list = new ArrayList();

 for (int i = 0; i a.length; i++) {

 list.add(a[i]);

 for (int i = 0; i diffOut.size(); i++) {

 Difference tempDiff = (Difference) diffOut.get(i);

 int delStart = tempDiff.getDeletedStart();

 int delEnd = tempDiff.getDeletedEnd();

 int addStart = tempDiff.getAddedStart();

 int addEnd = tempDiff.getAddedEnd();

 if (delEnd != -1) {

 // delEnd == -1 就是不进行刪除...

 // 删除开始.

 for (int j = delStart; j = delEnd; j++) {

 // 删除多个.

 list.remove(j);

 if (delStart != 0) {

 String temp = list.get(delStart - 1).toString();

 list.remove(delStart - 1);

 list

 .add(delStart - 1, temp + " del " + b[j]

 + " /del 

 } else {

 String temp = list.get(0).toString();

 list.remove(0);

 list.add(0, temp + " del " + b[j] + " /del 

 pirntList(list);

 if (addEnd != -1) {

 // addEnd == -1 就是不进行添加...

 // 下面添加的情况..

 for (int j = addStart; j = addEnd; j++) {

 // 添加多个.

 if (addStart list.size()) {

 list.add(" add " + b[j] + " /add 

 } else {

 list.add(addStart, " add " + b[j] + " /add 

 pirntList(list);

 pirntList(list);

 // return buffer.toString();

 public static void pirntList(List list) {

 StringBuffer buffer = new StringBuffer();

 for (int i = 0; i list.size(); i++) {

 buffer.append(""+list.get(i));

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

 }

通过ArrayList 实现对数据的整理.用remove 删除.用add(index,object)进行添加.

 

结果:

 

del: [1,-1] add: [1,2]
del: [3,3] add: [5,5]
a add x /add bcde
a add y /add add x /add bcde
a add y /add add x /add del b /del cde
a add y /add add x /add del b /del cd add j /add e
a add y /add add x /add del b /del cd add j /add e

 

最后显示了a变成b的全部过程.

 

 

 

 

 

 

 

 

项目中我们经常会用到的加载数据，加载完数据后显示内容，如果没有数据显示一个空白页，这是如果网络错误了显示一个网络错误页，自定义一个PageLayout。