JAVA1

import java.io.File;
import java.io.FileReader;
import java.io.FileWriter;
import java.io.IOException;


public class TestFile {

	/**
	 * @param args
	 */
	public static void main(String[] args) {
		// TODO Auto-generated method stub
		File f;
		FileReader in;
		FileWriter out;
		f=new File("c:\\test.txt");
		if(f.exists()){
			f.delete();
		}else{
			try{
				f.createNewFile();
				in=new FileReader(f);
				String str="好好学习，天天向上";
				
			}catch(IOException e){
				e.printStackTrace();
			}
		}
	}

}

package Testio;

import java.io.File;
import java.io.FileReader;
import java.io.IOException;



public class Testio {
	public static void main(String args[]){
		File f;
		FileReader in;
		FileReader out;
		f=new File("c:\\test.txt");
		if(f.exists()){
			f.delete();
		}else{
			try{
				f.createNewFile();
				in=new FileReader(f);
				String str="haohaoxuexi";
			}catch(IOException e){
				e.printStackTrace();
			}
		}
		
	}
}

import java.io.File;
import java.io.FileNotFoundException;
import java.io.FileReader;
import java.io.FileWriter;
import java.io.IOException;


public class TestFile {

	/**
	 * @param args
	 */
	public static void main(String[] args) {
		// TODO Auto-generated method stub
		File f;
		f=new File("c:\\test.txt");
		FileWriter out;
		FileReader in;
			try{
				/*
				String str="白日依山尽，黄河入海流\r\n欲穷千里目，更上一层楼。";
				out=new FileWriter(f);
				out.write(str);
				out.close();
				*/
				in=new FileReader(f);
				char cbuf[]=new char[(int)f.length()];
				in.read(cbuf);
				System.out.println(new String(cbuf).trim());
				in.close();
				
			}catch(FileNotFoundException e1){
				e1.printStackTrace();
			}catch(IOException e){
				e.printStackTrace();
			}
		}
	}