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Of course, the goal of this article is not to be speed, but to show that it is now easy to build a Spring web mvc Rest-style HelloWorld application.However, if you've seen the Spring Boot project, it may take up to three minutes to build a simple Rest-style application.Go back and share.

My Building Environment

JDK 7

Maven 3

Servlet3 Container

Create Project

First use Maven to create a normal Maven application, not a web application.

Add Dependency

<!-- servlet 3 -->
        <dependency>
            <groupId>javax.servlet</groupId>
            <artifactId>javax.servlet-api</artifactId>
            <version>3.0.1</version>
        </dependency>

        <!--spring context -->
        <dependency>
            <groupId>org.springframework</groupId>
            <artifactId>spring-context-support</artifactId>
            <version>4.0.0.RELEASE</version>
        </dependency>

        <!--spring webmvc -->
        <dependency>
            <groupId>org.springframework</groupId>
            <artifactId>spring-webmvc</artifactId>
            <version>4.0.0.RELEASE</version>
        </dependency>

        <!--jackson -->
        <dependency>
            <groupId>com.fasterxml.jackson.core</groupId>
            <artifactId>jackson-databind</artifactId>
            <version>2.2.3</version>
        </dependency>

servlet3 dependency scope is provided to represent environment provisioning, then adds spring-context-support and spring-webmvc dependencies, and finally jackson dependencies for json.It's very simple and clear.

Add a maven plugin

For testing purposes, add a jetty maven plug-in so that it runs directly using mvn jetty:run.

<build>
        <finalName>springmvc</finalName>
        <plugins>
            <plugin>
                <groupId>org.mortbay.jetty</groupId>
                <artifactId>jetty-maven-plugin</artifactId>
                <version>8.1.8.v20121106</version>
                <configuration>
                    <reload>manual</reload>
                    <webAppConfig>
                        <contextPath>/${project.build.finalName}</contextPath>
                    </webAppConfig>
                    <connectors>
                        <connector implementation="org.eclipse.jetty.server.nio.SelectChannelConnector">
                            <port>9080</port>
                            <!--<maxIdleTime>60000</maxIdleTime>-->
                        </connector>
                    </connectors>
                </configuration>
            </plugin>
        </plugins>
    </build>

Entities

package com.sishuok.entity;

import java.io.Serializable;

/**
 * <p>User: Zhang Kaitao
 * <p>Date: 13-12-19
 * <p>Version: 1.0
 */
public class User implements Serializable {
    private Long id;
    private String name;

    public Long getId() {
        return id;
    }

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

    public String getName() {
        return name;
    }

    public void setName(String name) {
        this.name = name;
    }

    @Override
    public boolean equals(Object o) {
        if (this == o) return true;
        if (o == null || getClass() != o.getClass()) return false;

        User user = (User) o;

        if (id != null ? !id.equals(user.id) : user.id != null) return false;

        return true;
    }

    @Override
    public int hashCode() {
        return id != null ? id.hashCode() : 0;
    }
}

Controller

package com.sishuok.controller;

import com.sishuok.entity.User;
import org.springframework.web.bind.annotation.PathVariable;
import org.springframework.web.bind.annotation.RequestMapping;
import org.springframework.web.bind.annotation.RequestMethod;
import org.springframework.web.bind.annotation.RestController;

/**
 * <p>User: Zhang Kaitao
 * <p>Date: 13-12-19
 * <p>Version: 1.0
 */
@RestController
@RequestMapping("/user")
public class UserController {

    @RequestMapping(value = "/{id}", method = RequestMethod.GET)
    public User view(@PathVariable("id") Long id) {
        User user = new User();
        user.setId(id);
        user.setName("zhang");
        return user;
    }
}

Specifically, do not introduce more, please refer to: New Spring4 Feature - Enhancement of Web Development "And" Learn Spring MVC from me>.

SpringMVC Annotation Style Configuration

@Configuration
@EnableWebMvc
@ComponentScan
public class AppConfig {
}

Refer to the specific meaning of " New Spring4 Feature - Groovy Bean Definition DSL "Section.

Servlet3 Container Start Initializer

Programmatically register Servlet at Servlet container startup

package com.sishuok;

import org.springframework.web.WebApplicationInitializer;
import org.springframework.web.context.WebApplicationContext;
import org.springframework.web.context.support.AnnotationConfigWebApplicationContext;
import org.springframework.web.servlet.DispatcherServlet;

import javax.servlet.ServletContext;
import javax.servlet.ServletException;
import javax.servlet.ServletRegistration;

/**
 * <p>User: Zhang Kaitao
 * <p>Date: 13-12-19
 * <p>Version: 1.0
 */
public class AppInitializer implements WebApplicationInitializer {

    @Override
    public void onStartup(ServletContext servletContext) throws ServletException {
        AnnotationConfigWebApplicationContext webApplicationContext =
                new AnnotationConfigWebApplicationContext();
        webApplicationContext.register(AppConfig.class);


        DispatcherServlet dispatcherServlet = new DispatcherServlet(webApplicationContext);
        ServletRegistration.Dynamic dynamic = servletContext.addServlet("dispatcherServlet", dispatcherServlet);
        dynamic.addMapping("/");

    }
} 

Refer to the specific meaning of " Learn Spring3 from me Of Chapter 12 And New Spring4 Feature - Groovy Bean Definition DSL And My github servlet3-showcase "Section.(

Then run mvn jetty:run and your browser will enter the following address to get our json data.

http://localhost:9080/springmvc/user/1

Reference example github address: springmvc-rest-helloworld

A very simple Rest-style web application is set up and ready to go.

The next article introduces building a spring mvc REST-style HelloWorld using Spring Boot in 2 minutes.