===== REST API =====

Representational State Transfer (REST) is a software architecture style consisting of guidelines and best practices for creating scalable web services. REST is a simpler alternative to SOAP and WSDL-based Web services. 

REST APIs communicate over the Hypertext Transfer Protocol (HTTP) (GET, POST, PUT, DELETE) used by web browsers.

=== CRUD ===

Simple transaction methods can be mapped to HTTP messages.

  * **C**REATE - POST
  * **R**EAD - GET
  * **U**PDATE - PUT
  * **D**ELETE - DELETE

=== JBOSS RestEasy ===

http://docs.jboss.org/resteasy/docs/3.0.7.Final/userguide/html_single/index.html

=== JSON (JavaScript Object Notation)===

Simple XML example of a data:

  <menu id="file" value="File">
    <popup>
      <menuitem value="New" onclick="CreateNewDoc()" />
      <menuitem value="Open" onclick="OpenDoc()" />
      <menuitem value="Close" onclick="CloseDoc()" />
    </popup>
  </menu>

The same in JSON format:

  {"menu": {
    "id": "file",
    "value": "File",
    "popup": {
    "menuitem": [
      {"value": "New", "onclick": "CreateNewDoc()"},
      {"value": "Open", "onclick": "OpenDoc()"},
      {"value": "Close", "onclick": "CloseDoc()"}
    ]
   }
  }}


===== Rest Api Example=====

1.) Create a dynamic web project: REST_API

2.) Copy the following class:

  package restapi;
  
  import java.util.HashSet;
  import java.util.Set;
  
  import javax.ws.rs.ApplicationPath;
  import javax.ws.rs.core.Application;
  
  import org.ait.rest.Restapi;
  
  @ApplicationPath("/rest")
  public class RestApplication extends Application {
	public Set<Class<?>> getClasses() {
		System.out.println("Restapi.class");
		Set<Class<?>> classes = new HashSet<Class<?>>();
		classes.add(Restapi.class);
		return classes;
	}
  }

3.) Create an other file (org.ait.rest.Restapi) with the following content:

  package org.ait.rest;
  
  import javax.enterprise.context.RequestScoped;
  import javax.ws.rs.GET;
  import javax.ws.rs.Path;
  import javax.ws.rs.PathParam;
  import javax.ws.rs.Produces;
  import javax.xml.bind.annotation.XmlElement;
  import javax.xml.bind.annotation.XmlRootElement;
  
  @RequestScoped
  @Path("restapi/{name}")
  public class Restapi {
  	
  	@GET
  	@Produces("application/json")
  	public Person testApi(@PathParam("name") String name) {
  		Person me = new Person();
  		me.name = name;
  		me.age = 18;
  		return me;
  	}	
  }
  
  @XmlRootElement(name = "Person")
  class Person {
  	String name;
  	@XmlElement
  	public String getName() {
  		return name;
  	}
  	@XmlElement
  	public int getAge() {
  		return age;
  	}
  	int age;
  }

4.) Browse: e.g.: http://localhost:8080/REST_API/rest/restapi/karcsi