IO流_PrintWriter(字符打印流)与PrintStream(字节打印流)

PrintStream:
   1.提供了打印方法可以对多种数据类型值进行打印,并保持数据的表示形式
   2.它不抛IOException
   3.构造函数接受三种类型的值:
     字符串路径
     File对象
     字节输出流

import java.io.FileNotFoundException;
import java.io.IOException;
import java.io.PrintStream;

public class PrintStreamDemo {
    public static void main(String[] args) throws IOException {
        PrintDemo();
    }
    private static void PrintDemo() throws IOException {
        PrintStream out = new PrintStream("F:\\print1.txt");
        //out.write(97);//写入门的是一个字节,只写最低8位,就是最低的那个字节
        
        out.print(97);//写入的是原样的数据,原理是先将数据变成字符串保持原样将数据打印到目的地
        
        out.close();
    }
}

 

PrintWriter:

  构造函数参数:
       字符串路径
       File对象
       字节输出流

       字符输出流

import java.io.BufferedReader;
import java.io.FileWriter;
import java.io.IOException;
import java.io.InputStreamReader;
import java.io.PrintWriter;

public class PrintWriterDemo {

    public static void main(String[] args) throws IOException {
        PrintDemo();
    }
    public static void PrintDemo() throws IOException {
        
        BufferedReader bufr = new BufferedReader(new InputStreamReader(System.in));
        
        //PrintWriter out = new PrintWriter(System.out,true);
        PrintWriter out = new PrintWriter(new FileWriter("F:\\0.txt"),true);
        String line = null;
        while((line = bufr.readLine())!=null){
            if("over".equals(line)){
                break;
            }
            out.println(line);//PrintWriter out = new PrintWriter(System.out,true);写了true会自动刷新
            //out.flush();
        }
        bufr.close();
        out.close();
    }
}

 

posted @ 2014-03-12 14:02  胡椒粉hjf  阅读(698)  评论(0编辑  收藏  举报