带缓冲的字符流

带缓冲的字符流

• BufferedReader的read()方法读取字符时会一次读取若干字符到缓冲区, 然后逐个返回给程序, 降低读取文件的次数, 提高效率

• BufferedWriter的write()方法写出字符时会先写到缓冲区, 缓冲区写满时才会写到文件, 降低写文件的次数, 提高效率

    //创建字符输入流对象,关联aaa.txt
    BufferedReader br = new BufferedReader(new FileReader("aaa.txt"));
    //创建字符输出流对象,关联bbb.txt
    BufferedWriter bw = new BufferedWriter(new FileWriter("bbb.txt"));
    
    int ch;
    //read一次,会先将缓冲区读满,从缓冲去中一个一个的返给临时变量ch
    while((ch = br.read()) != -1) {
    	//write一次,是将数据装到字符数组,装满后再一起写出去
    	bw.write(ch);
    }
    
    br.close();							//关流
    bw.close();