RESTful Java Play Framework

Simple ebean CRUD

Prerequisite

Play Framework 2.4.xDownload here

Setup the play framework (installing)JDK 1.8 (or later)IntelliJ CE

Create New Project

Through Command Line type: activator new

Create New Project

Open IntelliJ and import the new project

Create New Project

choose import project from external: SBT

And next just let the default value, click

finish

Create New Project

Here is the structure of Play

framework

The Objective

Create RESTful with Java Play FrameworkBuild basic API: GET, POST, PUT, DELETEBuild parameterize API

Use ORM (Object Relational Mapping) : Ebean

Configuration

plugin.sbt at project/ folder, uncomment or add this:addSbtPlugin("com.typesafe.sbt" % "sbt-play-ebean" % "1.0.0”)

Configuration

build.sbt (root)name := """Java-Play-RESTful-JPA"""

version := "1.0-SNAPSHOT"

lazy val root = (project in file(".")).enablePlugins(PlayJava, PlayEbean)

scalaVersion := "2.11.6"

libraryDependencies ++= Seq( javaJdbc, cache, javaWs)

routesGenerator := InjectedRoutesGenerator

Configuration

conf/application.conf, add:db.default.driver=org.h2.Driverdb.default.url="jdbc:h2:mem:play"db.default.jndiName=DefaultDSjpa.default=defaultPersistenceUnit

For simple purpose (development), we use mem as database on memory.

Configuration

Still on conf/application.conf, add:ebean.default="models.*”

This is as ORM related object model mapping

Create Simple POST

At conf/routes, we add url for API access.

POST /person controllers.Application.addPerson()

The method is POST, the access to this API is {baseurl}/person. For this example, we use json format for body.The process is on controllers/Application.java method addPerson()

Create models

Create models/Person.java

package models;

import com.avaje.ebean.Model;

import javax.persistence.Entity;import javax.persistence.Id;

@Entitypublic class Person extends Model{

@Id public Long id;

public String name;

public static Finder<Integer, Person> find = new Finder<Integer, Person>(Integer.class, Person.class);}

Create controller

Add the method addPerson() at controller application.java@BodyParser.Of(BodyParser.Json.class)public Result addPerson(){ JsonNode json = request().body().asJson();

Person person = Json.fromJson(json, Person.class);

if (person.toString().equals("")){ return badRequest("Missing parameter"); }

person.save(); return ok();}

Let’s tryFirst create run configuration: Choose SBT Task and chose for the Task is run.

Execute Run.

Because of the first time server start, it need trigger script evolution execute first by open the base url on the browser and apply the script.

Let’s try

Let curl from command line:

curl -X POST -H "Content-Type: application/json" -H "Cache-Control: no-cache" -d '{ "name":"Faren"}' 'http://localhost:9000/person’

It will store one object Person.

Create Simple GET

Add url on routesGET /person controllers.Application.listPerson()

Add controller Application.javapublic Result listPerson(){

List<Person> persons = new Model.Finder(String.class, Person.class).all();

return ok(toJson(persons));}

Let’s try

No need to Rerun the server. Just curl the GET method from command line.curl -X GET -H "Cache-Control: no-cache" 'http://localhost:9000/person’

The Output:[{"id":1,"name":"Faren"},{"id":33,"name":"Faren"}]

Get single record

Add url on routes

GET /person/:id controllers.Application.getPerson(id: Int)

Add controller Application.javapublic Result getPerson(int id){

Person person = Person.find.byId(id);

if (person == null){ return notFound("User not found!"); }

return ok(toJson(person));

}

Let’s try

Run curl on command line:curl -X GET -H "Cache-Control: no-cache" 'http://localhost:9000/person/1’

The Output:{ "id": 1, "name": "Faren"}

PUTAdd url on routesPUT /person/:id controllers.Application.updatePerson(id: Int)

Add controller Application.java@BodyParser.Of(BodyParser.Json.class)public Result updatePerson(int id){

Person person = Person.find.byId(id);

if (person == null){ return notFound("User not found"); }

JsonNode json = request().body().asJson(); Person personToBe = Json.fromJson(json, Person.class);

person = personToBe; person.update(); return ok();}

DELETE

Add url on routes

DELETE /person/:id controllers.Application.deletePerson(id: Int)

Add controller Application.java

public Result deletePerson(int id){

Person person = Person.find.byId(id);

if (person == null){ return notFound("User not found"); }

person.delete(); return ok();}

API with parameterFor example:http://localhost:9000/searchperson?name=Faren

Add url on routesGET /searchperson controllers.Application.searchPerson(name: String)

Add controller Application.javapublic Result searchPerson(String name){ List<Person> persons = Person.find.where() .like("name", "%"+name+"%") .findList();

if (persons == null){ return notFound("User not found!"); }

return ok(toJson(persons));

}

Full Source Code:

https://github.com/faren/java-play-ebean