关于java的IO中PrintWriter问题

Question

public class PrintIOTest {
public static void main(String[] ages){
try{
FileOutputStream fos = new FileOutputStream("test.txt");
PrintStream ps = new PrintStream(fos);
ps.print("hello,world!");

    }catch (FileNotFoundException e){
        e.printStackTrace();
    }


    /*try{
        FileWriter fw = new FileWriter("test.txt");
        PrintWriter pw = new PrintWriter(fw);
        pw.write("你好");
    }catch(IOException e){
        e.printStackTrace();
    }*/

}

}

用字节流外面套一个PrintStream运行正常，但是换成注释里的内容却只能新建test.tex，而不写内容，请问是怎么回事？？

Answer 1

用这个：
try {
FileWriter fw = new FileWriter("test.txt");
PrintWriter pw = new PrintWriter(fw);
pw.write("你好");
pw.close();
} catch (IOException e) {
e.printStackTrace();
}