Spring MVC REST Service Sample

applicationContext-mvc.xml

<?xml version="1.0" encoding="UTF-8"?>
<beans xmlns="http://www.springframework.org/schema/beans"
    xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
    xmlns:context="http://www.springframework.org/schema/context"
    xmlns:p="http://www.springframework.org/schema/p"
    xmlns:mvc="http://www.springframework.org/schema/mvc"
    xsi:schemaLocation="http://www.springframework.org/schema/beans http://www.springframework.org/schema/beans/spring-beans.xsd
        http://www.springframework.org/schema/context http://www.springframework.org/schema/context/spring-context.xsd
        http://www.springframework.org/schema/mvc http://www.springframework.org/schema/mvc/spring-mvc.xsd">

    <context:component-scan base-package="com.brunocesar" />

    <mvc:annotation-driven content-negotiation-manager="contentNegotiationManager" />

    <bean id="contentNegotiationManager" class="org.springframework.web.accept.ContentNegotiationManagerFactoryBean">
        <property name="defaultContentType" value="application/json" />
        <property name="mediaTypes">
            <value>
                json=application/json
                xml=application/xml
            </value>
        </property>
    </bean>

</beans>

Candidato.java

package com.brunocesar.bean;

public class Candidato {

    public Candidato() {}

    public Candidato(final long id, final String nome) {
        this.id = id;
        this.nome = nome;
    }

    private long id;
    private String nome;

    public long getId() {
        return id;
    }

    public void setId(final long id) {
        this.id = id;
    }

    public String getNome() {
        return nome;
    }

    public void setNome(final String nome) {
        this.nome = nome;
    }

}

CandidatoService.java

package com.brunocesar.service;

import java.util.List;

import com.brunocesar.bean.Candidato;

public interface CandidatoService {

    List<Candidato> listarCandidatos();

}

CandidatoServiceImpl.java

package com.brunocesar.service.impl;

import java.util.ArrayList;
import java.util.List;

import org.springframework.stereotype.Service;

import com.brunocesar.bean.Candidato;
import com.brunocesar.service.CandidatoService;

@Service
public class CandidatoServiceImpl implements CandidatoService {

    @Override
    public List<Candidato> listarCandidatos() {
        final List<Candidato> result = new ArrayList<>();
        result.add(new Candidato(1, "Pedro da Silva"));
        result.add(new Candidato(2, "Paula Pereira"));
        result.add(new Candidato(3, "<anonimo>"));
        return result;
    }

}

CandidatosWS.java

package com.brunocesar.ws;

import java.util.List;

import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.web.bind.annotation.RequestMapping;
import org.springframework.web.bind.annotation.RequestMethod;
import org.springframework.web.bind.annotation.RestController;

import com.brunocesar.bean.Candidato;
import com.brunocesar.service.CandidatoService;

@RestController
@RequestMapping(value = "/test")
public class CandidatosWS {

    @Autowired
    private CandidatoService candidatoService;

    @RequestMapping(value = "/candidatos", method = RequestMethod.GET)
    public List<Candidato> allCandidatos() {
        return candidatoService.listarCandidatos();
    }
}

SpringMvcWebInitializer.java

package com.brunocesar.config;

import org.springframework.web.servlet.support.AbstractAnnotationConfigDispatcherServletInitializer;

public class SpringMvcWebInitializer extends AbstractAnnotationConfigDispatcherServletInitializer {

    @Override
    protected Class<?>[] getRootConfigClasses() {
        return new Class[] {WebApplicationConfig.class};
    }

    @Override
    protected Class<?>[] getServletConfigClasses() {
        return null;
    }

    @Override
    protected String[] getServletMappings() {
        return new String[] {"/"};
    }

}

web.xml

<?xml version="1.0" encoding="UTF-8"?>
<web-app version="3.0" xmlns="http://java.sun.com/xml/ns/javaee"
    xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
    xsi:schemaLocation="http://java.sun.com/xml/ns/javaee http://java.sun.com/xml/ns/javaee/web-app_3_0.xsd"
    metadata-complete="true">

    <display-name>Test Application</display-name>

    <listener>
        <listener-class>org.springframework.web.context.request.RequestContextListener</listener-class>
    </listener>
    <listener>
        <listener-class>org.springframework.web.util.Log4jConfigListener</listener-class>
    </listener>

    <!-- spring servlet -->
    <servlet>
        <servlet-name>springDispatcherServlet</servlet-name>
        <servlet-class>org.springframework.web.servlet.DispatcherServlet</servlet-class>
        <init-param>
            <param-name>contextConfigLocation</param-name>
            <param-value>WEB-INF/applicationContext-mvc.xml</param-value>
        </init-param>
        <load-on-startup>0</load-on-startup>
    </servlet>
    <servlet-mapping>
        <servlet-name>springDispatcherServlet</servlet-name>
        <url-pattern>/</url-pattern>
    </servlet-mapping>

</web-app>

WebApplicationConfig.java

package com.brunocesar.config;

import org.springframework.context.annotation.ComponentScan;
import org.springframework.context.annotation.Configuration;
import org.springframework.http.MediaType;
import org.springframework.web.servlet.config.annotation.ContentNegotiationConfigurer;
import org.springframework.web.servlet.config.annotation.EnableWebMvc;
import org.springframework.web.servlet.config.annotation.WebMvcConfigurerAdapter;

@EnableWebMvc
@Configuration
@ComponentScan(basePackages = "com.brunocesar")
public class WebApplicationConfig extends WebMvcConfigurerAdapter {

    @Override
    public void configureContentNegotiation(final ContentNegotiationConfigurer configurer) {
        configurer.parameterName("mediaType")
                .defaultContentType(MediaType.APPLICATION_JSON)
                .mediaType("xml", MediaType.APPLICATION_XML)
                .mediaType("json", MediaType.APPLICATION_JSON);
    }

}