quick3.5的Luaj用法问题

java端:
package org.cocos2dx.jutils;

import javax.crypto.Cipher;
import javax.crypto.SecretKey;
import javax.crypto.spec.SecretKeySpec;

public class DESHelper {

public static String test(){
    return new String("hhhhhhhhhhhhuuuuuuuuuuuuu");
}

}
Lua端:
local flag,encode = luaj.callStaticMethod(“org/cocos2dx/juitls/DESHelper”, “test”)

直接崩掉,求大神解答