java 文件读写

import java.io.BufferedReader;import java.io.BufferedWriter;import java.io.File;import java.io.FileNotFoundException;import java.io.FileReader;import java.io.FileWriter;import java.io.IOException;//文件读写public class FileDemo {public static void main(String[] args) {StringBuffer line=null;try {FileReader fr = new FileReader("C:/test.txt");BufferedReader br =new BufferedReader(fr); line=new StringBuffer();while (br.ready()) {line.append(br.readLine());}br.close();} catch (FileNotFoundException e) {// e.printStackTrace();} catch (IOException e) {// e.printStackTrace();}try {File f =new File("D:/test.txt");FileWriter fw = new FileWriter(f);BufferedWriter bw = new BufferedWriter(fw);bw.write(line.toString());bw.flush();bw.close();} catch (IOException e) {// e.printStackTrace();}}}