Question

I like to expose one JAVA method as a Web service that will accept POST ,strip the parameters out of it and reply accordingly. I read I have to use doPost(req,resp) , but How can I get to the servlet code? what should be in web.xml? there will not be a welcome-file ? After mapping the servlet, can I read it without the need for a index.html as start point?

Answer 1

create the doPost(req,resp) method in your servlet and map it to a url in web.xml

<servlet>
        <servlet-name>HelloPost</servlet-name>
        <servlet-class>packageName.HelloPost</servlet-class>
</servlet>

<servlet-mapping>
        <servlet-name>HelloPost</servlet-name>
        <url-pattern>/post-url</url-pattern>
</servlet-mapping>

then you can post your request to /post-url .You don’t need to use index.html.Any url can be put in welcome file to load for the url /
To set /post-url as landing page , use

<welcome-file-list>
        <welcome-file>/post-url</welcome-file>
</welcome-file-list> 

you can get started here https://developers.google.com/appengine/docs/java/gettingstarted/creating