java JNative 调用 dll 的一个方法参数怎么设置啊

PB语言 解密示例:

long ll_size 
string ls_outpass 
string ls_inpass

ls_inpass = trim(as_toDecrypt)
ll_size = b64_size(len(ls_inpass),1) 
ls_outpass = space(ll_size) 
b64_des(ls_inpass,ls_outpass,is_key,len(ls_inpass),0) 
return ls_outpass

然后Java的参数改怎样设置, 下面是我写的方法，好像不对：

byte[] ls_inpass_byte = ls_inpass.getBytes();
                  Pointer ls_outpass = new Pointer(MemoryBlockFactory.createMemoryBlock(outLen*4));
                getUrl = new JNative("des64.dll", "b64_des"); 
                   getUrl.setRetVal(Type.STRING);
                   getUrl.setParameter(0, Type.VOID, ls_inpass_byte); 
                   getUrl.setParameter(1, ls_outpass);
                   getUrl.setParameter(2, Type.STRING,key);
                   getUrl.setParameter(3, ls_inpass.length());
                   getUrl.setParameter(4, Type.INT,"0");
                   getUrl.invoke(); //调用方法
                   System.out.println("解密结果:"+getUrl.getRetVal()); //输出返回值