fileiodemo.txt

来自「主要是java书上的一些代码」· 文本 代码 · 共 56 行

1: //: FileIODemo.java
2: 
3: //package g3ds.joop.ch7;
4: 
5: import java.io.*;
6: 
7: public class FileIODemo{
8: 	private String strTemp;
9: 	private String  strFinal=new String();
10: 	
11: 	//测试
12: 	public static void main(String[] args) throws IOException{
13: 		FileIODemo obj = new FileIODemo();
14: 		
15: 		//打开一个文件FileIODemo.java
16: 		obj.open("FileIODemo.java");
17: 		//把它另存为FileIODemo.txt，并加上行号
18: 		obj.saveAs("FileIODemo.txt");
19: 	}
20: 	
21: 	public void open(String fileName){
22: 		try{
23: 			//把文件内容读入缓存
24: 			BufferedReader in = new BufferedReader(
25: 				new FileReader(fileName));
26: 		
27: 			while((strTemp = in.readLine())!= null)
28: 				strFinal += strTemp + "\n";
29: 			
30: 			//关闭文件
31: 			in.close();
32: 		}catch(IOException e){}
33: 	}
34: 	
35: 	public void saveAs(String fileName){
36: 		try {
37:       		//读入缓存中文件的内容
38:       		BufferedReader in = new BufferedReader(
39: 				new StringReader(strFinal));
40: 			
41: 			//定义写出的文件名
42: 			PrintWriter out = new PrintWriter(
43: 				new BufferedWriter(new FileWriter(fileName)));
44:             
45:             //写过程
46: 			int lineCount = 1;
47: 			while((strTemp = in.readLine()) != null )
48: 				out.println(lineCount++ + ": " + strTemp);
49: 			
50: 			//关闭文件
51: 			in.close();	
52: 			out.close();
53: 		} catch(IOException e) {}
54: 	}
55: }