Liferay is easy: Liferay Custom JSON Web Services

Liferay give you JSON web services for its entities like groups, organization etc . You can see all those services by this URL http://localhost:8080/api/jsonws .

But today we will create our own Entity like Student and access the methods by URLs and get JSON response. So Lets start this step by step:-

Step 1:-Create Service Builder
My database table name is student with this data:-

And my service.xml is:-

	<?xml version="1.0" encoding="UTF-8"?>
	<!DOCTYPE service-builder PUBLIC "-//Liferay//DTD Service Builder 6.2.0//EN" "http://www.liferay.com/dtd/liferay-service-builder_6_2_0.dtd">
	<service-builder package-path="com.services">
	<author>aditya.bhardwaj</author>
	<namespace>restapi</namespace>
	<entity name="Student" table="student" local-service="true" remote-service="true">
	<column name="sid" type="long" primary="true" id-type="increment"></column>
	<column name="studentName" type="String"></column>
	<column name="address" type="String"></column>
	<column name="phone" type="String"></column>
	</entity>
	</service-builder>

view raw service.xml hosted with ❤ by GitHub

Now Build Services.

Explanation:-
We already discuss how to create service builder in Liferay .
Here we also provide tag remote-service="true" which is needed for Rest Services.

Step 2:-Change xxxServiceImpl
When you build services it will create a xxxServiceImpl class .Now create your method which you want as JSON API in StudentServiceImpl :-

StudentServiceImpl.java

	package com.services.service.impl;
	import com.liferay.portal.kernel.exception.PortalException;
	import com.liferay.portal.kernel.exception.SystemException;
	import com.liferay.portal.security.ac.AccessControlled;
	import com.services.model.Student;
	import com.services.service.StudentLocalServiceUtil;
	import com.services.service.base.StudentServiceBaseImpl;

	public class StudentServiceImpl extends StudentServiceBaseImpl {

	@AccessControlled(guestAccessEnabled = true)
	public Student getStudentDetail(long sid) throws PortalException, SystemException{
	return StudentLocalServiceUtil.getStudent(sid);
	}
	}

view raw StudentServiceImpl.java hosted with ❤ by GitHub

Now again Build Services.

Explanation:-
1)Here we create getStudentDetail which internally call method from Util Class so basically we expose our method For Rest API.
2)We annotate our method with:-
@AccessControlled(guestAccessEnabled = true)
so that you can access this method without login. If you want that no one access this method without login simply remove this annotation.

Step 3:-Check Output
Now deploy your portlet and hit http://localhost:8080/api/jsonws in your browser and select your project from context path:-

Now Click on your method get-student-detail

provide studentId and click on Invoke:-

You will see the Result. Now you can click on JavaScipt Example:-

URL Example:-

You can directly hit this URL in browser and see the Json response.

Step 5:-Access in Jsp
You can access the JSON rest web services in jsp as:-

view.jsp

	<%@ taglib uri="http://alloy.liferay.com/tld/aui" prefix="aui" %>
	<%@ taglib uri="http://java.sun.com/portlet_2_0" prefix="portlet" %>
	<portlet:defineObjects />

	<aui:form method="GET" name="<portlet:namespace />fm">
	<aui:fieldset>
	<aui:input label="Student ID" name="student-ID"></aui:input>
	</aui:fieldset>
	<aui:button-row><aui:button id="get-student-detail" value="Get Student Detail"></aui:button></aui:button-row>
	</aui:form>

	<aui:script use="node, event">
	var getStudentDetail = A.one('#get-student-detail');
	var studentIDNode = A.one('#<portlet:namespace />student-ID');

	getStudentDetail.on('click', function(event) {
	var studentID = studentIDNode.get('value');
	var studentDetail = Liferay.Service(
	'/restAPI-portlet.student/get-student-detail',
	{
	sid: studentID
	},
	function(obj) {
	alert("Details=>"+obj.studentName+"-"+obj.address);
	console.log(obj);
	}
	);
	});
	</aui:script>