java读写 功能

package model;

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

public class FileReadDemo {
	public static void main(String[] args){
		try {
			FileReader fr = new FileReader("E:\\demo.txt");
			char[] arr = new char[1024];
			int num = 0;
			 try {
				while((num = fr.read(arr))!=-1)
				    {
				        System.out.println(new String(arr,0,num));
				    }
			} catch (IOException e) {
				// TODO Auto-generated catch block
				e.printStackTrace();
			}

		} catch (FileNotFoundException e) {
			// TODO Auto-generated catch block
			e.printStackTrace();
		}
	}
}