java复制的五种方法

第一种：

private static void methods1() throws FileNotFoundException, IOException {
	//字符流 -- 一次读写一个字符
	//创建输入流对象
	FileReader fr = new FileReader("a_FileWriterDemo_0216.java");
		
	//创建输出流对象
	FileWriter fw = new FileWriter("1.txt");
		
	//一次读取一个字符
	int ch;
	while((ch = fr.read())!=-1){
		fw.write(ch);
	}
		
	//释放资源
	fw.close();
	fr.close();
}

第二种：

private static void methods2() throws FileNotFoundException, IOException {
    //字符流 -- 一次读写一个字符
    //创建输入流对    
    FileReader fr = new FileReader("a_FileWriterDemo_0216.java");

    //创建输出流对象
    FileWriter fw = new FileWriter("2.txt");
	
    //一次读取一个字符数组
    char[]chs = new char[1024];
    int len;
    while((len = fr.read(chs))!=-1){
        fw.write(chs,0,len);
    }
    
    //释放资源
    fw.close();
    fr.close();
}

第三种 ：

private static void methods3() throws FileNotFoundException, IOException {
    //缓冲流一次读取一个字符
	//创建输入缓冲流对象
	BufferedReader br = new BufferedReader(new FileReader("a_FileWriterDemo_0216.java"));
	//创建输出缓冲流对象
	BufferedWriter bw = new BufferedWriter(new FileWriter("3.txt "));
	
	//一次读写一个字符
	int ch;
	while((ch = br.read())!=-1){
		bw.write(ch);
	}
		
	//释放资源
	bw.close();
	br.close();
}

第四种：

private static void methods4() throws FileNotFoundException, IOException {
	//缓冲流一次读取一个字符数组
	//创建输入缓冲流对象
	BufferedReader br = new BufferedReader(new FileReader("a_FileWriterDemo_0216.java"));
	//创建输出缓冲流对象
	BufferedWriter bw = new BufferedWriter(new FileWriter("4.txt "));
		
	//一次读写一个字符
	char[] chs = new char[1024];
	int len;
	while((len = br.read(chs))!=-1){
		bw.write(chs,0,len);
	}
		
	//释放资源
	bw.close();
	br.close();
}

第五种：

private static void meyhods5() throws FileNotFoundException, IOException {
	//缓冲流一次读取一个字符串
	//创建输入缓冲流对象
	BufferedReader br = new BufferedReader(new FileReader("a_FileWriterDemo_0216.java"));
	//创建输出缓冲流对象
	BufferedWriter bw = new BufferedWriter(new FileWriter("5.txt "));
		
	//一次读写一个字符串
	String line;
	while((line = br.readLine())!=null){
		bw.write(line);
		bw.newLine();
		bw.flush();
	}
		
	//释放资源
	bw.close();
	br.close();
}

 主方法

public static void main(String[] args) throws Exception {
	methods1();
	methods2();
	methods3();
	methods4();
	meyhods5();	
}