UTF-8项目发送GBK报文，JAVA实现UTF-8转码为GBK

String t = xml;
String utf8 = new String(t.getBytes( "UTF-8"));
System.out.println(utf8);
String unicode = new String(utf8.getBytes(),"UTF-8");
System.out.println(unicode);
String gbk = new String(unicode.getBytes("GBK"));
System.out.println(gbk);

不过这个方法是无法把中文转码的。中文转码需要用

URLEncoder这个方法