File复制文本文件

package cn.itcast_01;


import java.io.BufferedReader;
import java.io.BufferedWriter;
import java.io.FileReader;
import java.io.FileWriter;
import java.io.IOException;


/*
 * 复制文本文件
 * 
 * 分析：
 * 复制数据，如果我们知道用记事本打开并能够读懂，就用字符流，否则用字节流。
 * 通过该原理，我们知道我们应该采用字符流更方便一些。
 * 而字符流有5种方式，所以做这个题目我们有5种方式。推荐掌握第5种。
 * 数据源：
 * c:\\a.txt -- FileReader -- BufferdReader
 * 目的地：
 * d:\\b.txt -- FileWriter -- BufferedWriter
 */
public class CopyFileDemo {
public static void main(String[] args) throws IOException {
String srcString = "c:\\a.txt";
String destString = "d:\\b.txt";
// method1(srcString, destString);
// method2(srcString, destString);
// method3(srcString, destString);
// method4(srcString, destString);
method5(srcString, destString);
}


// 字符缓冲流一次读写一个字符串
private static void method5(String srcString, String destString)
throws IOException {
BufferedReader br = new BufferedReader(new FileReader(srcString));
BufferedWriter bw = new BufferedWriter(new FileWriter(destString));


String line = null;
while ((line = br.readLine()) != null) {
bw.write(line);
bw.newLine();
bw.flush();
}


bw.close();
br.close();
}


// 字符缓冲流一次读写一个字符数组
private static void method4(String srcString, String destString)
throws IOException {
BufferedReader br = new BufferedReader(new FileReader(srcString));
BufferedWriter bw = new BufferedWriter(new FileWriter(destString));


char[] chs = new char[1024];
int len = 0;
while ((len = br.read(chs)) != -1) {
bw.write(chs, 0, len);
}


bw.close();
br.close();
}


// 字符缓冲流一次读写一个字符
private static void method3(String srcString, String destString)
throws IOException {
BufferedReader br = new BufferedReader(new FileReader(srcString));
BufferedWriter bw = new BufferedWriter(new FileWriter(destString));


int ch = 0;
while ((ch = br.read()) != -1) {
bw.write(ch);
}


bw.close();
br.close();
}


// 基本字符流一次读写一个字符数组
private static void method2(String srcString, String destString)
throws IOException {
FileReader fr = new FileReader(srcString);
FileWriter fw = new FileWriter(destString);


char[] chs = new char[1024];
int len = 0;
while ((len = fr.read(chs)) != -1) {
fw.write(chs, 0, len);
}


fw.close();
fr.close();
}


// 基本字符流一次读写一个字符
private static void method1(String srcString, String destString)
throws IOException {
FileReader fr = new FileReader(srcString);
FileWriter fw = new FileWriter(destString);


int ch = 0;
while ((ch = fr.read()) != -1) {
fw.write(ch);
}


fw.close();
fr.close();
}
}