import java.io.FileNotFoundException;
import java.io.FileOutputStream;
import java.io.PrintStream;

public class Practice06 {
    public static void main(String[] args) throws FileNotFoundException {
        PrintStream ps=new PrintStream(new FileOutputStream("f.text"));
        ps.println("字节打印流");//默认自动换行
        ps.print("666");
        ps.printf("%s","字符串");//占位符打印
        ps.close();
    }
}

import java.io.FileNotFoundException;
import java.io.FileOutputStream;
import java.io.PrintWriter;

public class Practice07 {
    public static void main(String[] args) throws FileNotFoundException {
        PrintWriter pw=new PrintWriter(new FileOutputStream("g.text"),true);
        //要把true开关打开，否则不会在文件中写下数据.
        pw.println("hello,world!");
        pw.print("你好");
        pw.printf("%d",12);
    }
}