如何在java web service中调用一个方法？

Question

I'm a learner of both java and android programming. I made a web service of hello world. Created a class called HelloWorld. There is only one method in it like

sayHello(){
System.out.println("hello world")
}

Now how should I write a android main activity to invoke this method using http request. what are the prerequisites to use http request. What are the libraries to import. Should I download any library from any where? I googled for it. Many irrelevant results are coming. I'm not able to comprehend from them.So seeking help here which seemed to be the only option.

Kind answer is appreciated.

Answer 1

The Android platform comes with everything you need to make HTTP requests. You should take a look at the URLHttpConnection. Bear in mind, that making an HTTP request is a bit harder then just using this class. You should think about doing it on a worker thread, so you don't block the UI. You should also think about the data transfer protocol you are going to use for your client - server communication and how to process the received responses.

I think this can get you started: http://developer.android.com/training/basics/network-ops/connecting.html

When you feel more comfortable with the concept, you can try and use a library for your HTTP request. Here is a useful link: https://developer.android.com/training/volley/index.html

Only one thing - seems like your web service is not sending any data back to clients, it's just printing to the server standard output, so it is unlikely you see any information sent to your Android app.