在php中，怎样把字符串转为UTF-8字节数组？

Test.java

import java.io.*;

public class Test{

    public static void main(String args[]){
        String Str1 = new String("在php中");

        try{
            byte[] bytes = Str1.getBytes("UTF-8");

            StringBuilder sb = new StringBuilder();

            for (byte b : bytes) {
                sb.append(String.format("%d ", b & 0xff));
            }

            System.out.println(sb.toString());

        }catch( UnsupportedEncodingException e){
            System.out.println("Unsupported character set");
        }
    }
}