zoukankan      html  css  js  c++  java
  • Spring4 MVC RESTFul WebServices CRUD实例+RestTemplate

    简单介绍REST

    REST 表示状态传输。这是一个体系结构样式,可用于设计网络服务,可以被各种客户端消耗。核心思想是,不使用如CORBA,RPC或SOAP复杂的机制在机器之间进行连接,简单的 HTTP 用于使它们之间调用。

    在基于 REST 的设计中,资源被一套通用动词操作使用。
    • 创建资源:应该使用 HTTP POST
    • 要获取资源:应该使用HTTP GET
    • 更新资源:应使用HTTP PUT
    • 要删除资源:应使用HTTP DELETE
    这意味着,作为一个 REST 服务开发人员或客户端,应符合上述标准,以便 REST 操作。

    通常Rest 是基于Web服务返回JSON或XML数据格式作为响应,虽然它并不仅仅限于这些类型。客户端可以指定(使用 HTTP Accept 报头),他们所感兴趣的资源类型,并且服务器可以返回资源,指定它所服务的内容类型资源。 

    基于REST的控制器

    下面是一个可能基于 REST 的控制器,实现REST API。这里所说的“可能”,这意味着可以以另一种方式实现它,还是(或者更纯粹的方式)符合REST风格。

    这就是我们的 REST API 功能/作用:
    • GET 请求 /api/user/ 返回用户的列表
    • GET 请求  /api/user/1 返回ID为1的用户
    • POST 请求 /api/user/ 以用户对象的JSON格式创建新的用户
    • PUT 请求 /api/user/3 以用户对象作为JSON更新ID为3的用户
    • DELETE 请求 /api/user/4 删除ID为4的用户
    • DELETE 请求 /api/user/ 删除所有的用户

    需要用到的java包

    java对象和json相互转化

    jackson-mapper-asl
    jackson-databind
    

      

    pom.xml

    <properties>
      	<springVersion>4.3.5.RELEASE</springVersion>  
      	<jacksonVersion>2.7.4</jacksonVersion>  	
      </properties>
      
      <dependencies>
      
      
         <!-- spring-test支持 -->
        <dependency>
        	<groupId>org.springframework</groupId>
        	<artifactId>spring-test</artifactId>
        	<version>${springVersion}</version>
        </dependency>
        <dependency>
          <groupId>junit</groupId>
          <artifactId>junit</artifactId>
          <version>4.11</version>
          <scope>test</scope>
        </dependency>
        
        
        
          <!-- spring模块库 -->
        <dependency>
        	<groupId>org.springframework</groupId>
        	<artifactId>spring-beans</artifactId>
        	<version>${springVersion}</version>
        </dependency> 
        <dependency>
        	<groupId>org.springframework</groupId>
        	<artifactId>spring-web</artifactId>
        	<version>${springVersion}</version>
        </dependency>
        <dependency>
        	<groupId>org.springframework</groupId>
        	<artifactId>spring-webmvc</artifactId>
        	<version>${springVersion}</version>
        </dependency>  
    	<!-- https://mvnrepository.com/artifact/org.springframework/spring-tx -->
    	<dependency>
    	    <groupId>org.springframework</groupId>
    	    <artifactId>spring-tx</artifactId>
    	    <version>${springVersion}</version>
    	</dependency>
    	
        
        <!-- Servlet dependencies -->
        <!-- servlet(HttpServletRequest,HttpServletResponse) -->	
    	<dependency>
    		<groupId>javax.servlet</groupId>
    		<artifactId>javax.servlet-api</artifactId>
    		<version>3.1.0</version>
    	</dependency>
        
        <!-- https://mvnrepository.com/artifact/org.codehaus.jackson/jackson-mapper-asl -->
    	<!-- java对象和json相互转化 -->	
    	<dependency>
    	    <groupId>org.codehaus.jackson</groupId>
    	    <artifactId>jackson-mapper-asl</artifactId>
    	    <version>1.9.13</version>
    	</dependency>
    	<dependency>
            <groupId>com.fasterxml.jackson.core</groupId>
            <artifactId>jackson-databind</artifactId>
            <version>2.7.4</version>
        </dependency>
        
        
      </dependencies>
      
      
      
      <build>
      	<pluginManagement>
      		<plugins>
      			<plugin>
        			<groupId>org.apache.maven.plugins</groupId>
        			<artifactId>maven-war-plugin</artifactId>
        			<version>2.6</version>
        			<configuration>
        				<warSourceDirectory>src/main/webapp</warSourceDirectory>
        				<warName>gugua11</warName>
        				<failOnMissingWebXml>false</failOnMissingWebXml>
        			</configuration>
        		</plugin>
      		</plugins>
      	</pluginManagement>
        <finalName>gugua11</finalName>
      </build>
    

      

    user字段结构

    user.java

    package springmvc.model;
    
    public class User {
    
    	private long id;
    	private String name;
    	private int age;
    	private double salary;
    	
    	
    	
    	
    	public User() {
    		id=0;
    	}
    
    
    	public User(long id, String name, int age, double salary) {	
    		this.id = id;
    		this.name = name;
    		this.age = age;
    		this.salary = salary;
    	}
    	
    	
    	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;
    	}
    	
    	
    	public int getAge() {
    		return age;
    	}
    	public void setAge(int age) {
    		this.age = age;
    	}
    	
    	
    	public double getSalary() {
    		return salary;
    	}
    	public void setSalary(double salary) {
    		this.salary = salary;
    	}
    
    	
    
    	@Override
    	public int hashCode() {
    		final int prime = 31;
    		int result = 1;		
    		result = prime * result + (int) (id ^ (id >>> 32));		
    		return result;
    	}
    
    
    	@Override
    	public boolean equals(Object obj) {		
    		if (this == obj)
    			return true;		
    		if (obj == null)
    			return false;		
    		if (getClass() != obj.getClass())
    			return false;		
    		User other = (User) obj;
    		if (id != other.id)
    			return false;		
    		return true;
    	}
    	
    		
    	
    	
    }
    

      

    userService接口

    package springmvc.service;
    
    import java.util.List;
    
    import springmvc.model.User;
    
    public interface UserService {
    
    	
    	User findById(long id);
    	
    	User findByName(String name);
    	
    	void saveUser(User user);
    	
    	void updateUser(User usre);
    	
    	void deleteUserById(long id);
    	
    	List<User> findAllUser();
    	
    	void deleteAllUser();
    	
    	public boolean isUserExists(User user);
    }
    

      

    userServiceImplement接口实现

    @Service("userService")   #声明服务,用于自动装配
    @Transactional  #事务支持(类似于msql事务提交)

    package springmvc.service;
    
    import java.util.ArrayList;
    import java.util.Iterator;
    import java.util.List;
    import java.util.concurrent.atomic.AtomicLong;
    
    import org.springframework.stereotype.Service;
    import org.springframework.transaction.annotation.Transactional;
    
    import springmvc.model.User;
    
    @Service("userService")
    @Transactional
    public class UserServiceImpl implements UserService {
    
    	private static final AtomicLong counter = new AtomicLong();
    	private static List<User> users;
    	
    	static {
    		users = populateDummyUsers();
    	}
    	
    	
    	@Override
    	public List<User> findAllUser() {
    		// TODO Auto-generated method stub
    		return users;
    	}
    	
    	@Override
    	public User findById(long id) {
    		// TODO Auto-generated method stub
    		for(User user: users)
    		{
    			if(user.getId() == id)
    			{
    				return user;
    			}
    		}
    		return null;
    	}
    
    	@Override
    	public User findByName(String name) {
    		// TODO Auto-generated method stub
    		for(User user: users)
    		{
    			if(user.getName().equals(name) )
    			{
    				return user;
    			}
    		}
    		return null;
    	}
    
    	@Override
    	public void saveUser(User user) {
    		// TODO Auto-generated method stub
    		user.setId(counter.incrementAndGet());
    		users.add(user);
    	}
    
    	@Override
    	public void updateUser(User user) {
    		// TODO Auto-generated method stub
    		int index = users.indexOf(user);
    		users.set(index, user);
    	}
    
    	@Override
    	public void deleteUserById(long id) {
    		// TODO Auto-generated method stub
    		for(Iterator<User> iterator = users.iterator(); iterator.hasNext();)
    		{
    			User user = iterator.next();
    			if(user.getId() == id)
    			{
    				iterator.remove();
    			}
    		}
    	}
    
    	@Override
    	public boolean isUserExists(User user) {
    		// TODO Auto-generated method stub
    		return findByName(user.getName())!=null;
    	}
    	
    
    	@Override
    	public void deleteAllUser() {
    		// TODO Auto-generated method stub
    		users.clear();
    	}
    
    	//默认数据
    	public static List<User> populateDummyUsers()
    	{
    		List<User> users = new ArrayList<User>();
    		users.add(new User(counter.incrementAndGet(), "张三", 30, 700000));
    		users.add(new User(counter.incrementAndGet(), "李四", 35, 850000));
    		users.add(new User(counter.incrementAndGet(), "王五", 36, 900000));
    		users.add(new User(counter.incrementAndGet(), "田七", 38, 1000000));
    		return users;
    		
    	}
    	
    
    }
    

      

    输出头部信息

    CORSFilter.java

    package springmvc.configuration;
    
    
    import java.io.IOException;
    
    import javax.servlet.Filter;
    import javax.servlet.FilterChain;
    import javax.servlet.FilterConfig;
    import javax.servlet.ServletException;
    import javax.servlet.ServletRequest;
    import javax.servlet.ServletResponse;
    import javax.servlet.http.HttpServletResponse;
    
    //支持跨域操作
    public class CORSFilter implements Filter {
    
    
    	
    
    	@Override
    	public void doFilter(ServletRequest req, ServletResponse res, FilterChain chain)
    			throws IOException, ServletException {
    		// TODO Auto-generated method stub
    		System.out.print("Filtering on .......");
    		HttpServletResponse response = (HttpServletResponse) res;
    		response.setHeader("Access-Control-Allow-Origin", "*");
    		response.setHeader("Access-Control-Allow-Methods", "POST, GET, PUT, OPTIONS, DELETE");
    		response.setHeader("Access-Control-Max-Age", "3600");
    		response.setHeader("Access-Control-Allow-Headers", "x-requested-with");
    		chain.doFilter(req, res);	
    	}
    
    	@Override
    	public void init(FilterConfig arg0) throws ServletException {
    		// TODO Auto-generated method stub
    		
    	}
    	
    	@Override
    	public void destroy() {
    		// TODO Auto-generated method stub
    		
    	}
    
    	
    	
    }
    

      

    springmvc,自动引入,配置声明

    package springmvc.configuration;
    
    import org.springframework.context.annotation.ComponentScan;
    import org.springframework.context.annotation.Configuration;
    import org.springframework.web.servlet.config.annotation.EnableWebMvc;
    
    @Configuration
    @EnableWebMvc
    @ComponentScan(basePackages="springmvc")
    public class HelloWorldConfiguration {
    
    
    }
    

      

    初始分Dispatcher转发功能

    package springmvc.configuration;
    
    import javax.servlet.Filter;
    
    import org.springframework.web.servlet.support.AbstractAnnotationConfigDispatcherServletInitializer;
    
    public class HelloWorldInitializer extends AbstractAnnotationConfigDispatcherServletInitializer {
    
    	@Override
    	protected Class<?>[] getRootConfigClasses() {
    		// TODO Auto-generated method stub
    		return new Class[] { HelloWorldConfiguration.class };
    	}
    
    	@Override
    	protected Class<?>[] getServletConfigClasses() {
    		// TODO Auto-generated method stub
    		return null;
    	}
    
    	@Override
    	protected String[] getServletMappings() {
    		// TODO Auto-generated method stub
    		return new String[]{"/"};
    	}
    	
    	@Override
    	protected Filter[] getServletFilters()
    	{
    		Filter [] singleton = { new CORSFilter()};
    		return singleton;
    		
    	}
    
    	
    	
    	
    }
    

      

    控制器

    package springmvc.controller;
    
    import java.util.List;
    
    import org.springframework.beans.factory.annotation.Autowired;
    import org.springframework.http.HttpHeaders;
    import org.springframework.http.HttpStatus;
    import org.springframework.http.MediaType;
    import org.springframework.http.ResponseEntity;
    import org.springframework.web.bind.annotation.PathVariable;
    import org.springframework.web.bind.annotation.RequestBody;
    import org.springframework.web.bind.annotation.RequestMapping;
    import org.springframework.web.bind.annotation.RequestMethod;
    import org.springframework.web.bind.annotation.RestController;
    import org.springframework.web.util.UriComponentsBuilder;
    
    import springmvc.model.User;
    import springmvc.service.UserService;
    
    @RestController
    public class HelloWorldRestController {	
    		
    	
    	@Autowired
    	UserService userService;	
    
    	
    	@RequestMapping(value="/users", method=RequestMethod.GET)
    	public ResponseEntity<List<User>> listAllUsers()
    	{
    		List<User> users = userService.findAllUser();
    		if(users.isEmpty())
    		{
    			return new ResponseEntity<List<User>>(HttpStatus.NO_CONTENT);
    		}
    		return new ResponseEntity<List<User>>(users, HttpStatus.OK) ;
    		
    	}
    	
    	@RequestMapping(value="/user/{id}", method=RequestMethod.PUT, produces=MediaType.APPLICATION_JSON_VALUE)
    	public ResponseEntity<User> getUser(@PathVariable("id") long id)
    	{
    		User user = userService.findById(id);
    		if(user == null)
    		{
    			return new ResponseEntity<User>(HttpStatus.NOT_FOUND);
    		}
    		return new ResponseEntity<User>(user, HttpStatus.OK);
    		
    	}
    	
    	@RequestMapping(value="/user/{name}", method=RequestMethod.GET, produces=MediaType.APPLICATION_JSON_VALUE)
    	public ResponseEntity<User> getNameUser(@PathVariable("name") String name)
    	{
    		User user = userService.findByName(name);
    		if(user == null)
    		{
    			return new ResponseEntity<User>(HttpStatus.NOT_FOUND);
    		}
    		return new ResponseEntity<User>(user, HttpStatus.OK);
    	}
    	
    	@RequestMapping(value="/user/create", method=RequestMethod.POST)
    	public ResponseEntity<Void> createUser(@RequestBody User user, UriComponentsBuilder uriBuilder)
    	{
    		if(userService.isUserExists(user))
    		{
    			return new ResponseEntity<Void>(HttpStatus.CONFLICT); 
    		}
    		userService.saveUser(user);
    		
    		HttpHeaders headers = new HttpHeaders();
    		headers.setLocation(uriBuilder.path("/user/{id}").buildAndExpand(user.getId()).toUri());
    		
    		return new ResponseEntity<Void>(headers, HttpStatus.CREATED);
    		
    	}
    	
    	
    }
    

      

    @RequestMapping(value="/user/delete/{id}", method=RequestMethod.GET, produces=MediaType.APPLICATION_JSON_VALUE)
    	public ResponseEntity<User> deleteUserOne(@PathVariable("id") long id)
    	{
    		User user = userService.findById(id);
    		if(user == null)
    		{
    			return new ResponseEntity<User>(HttpStatus.NOT_FOUND);
    		}
    		userService.deleteById(id);
    		return new ResponseEntity<User>(HttpStatus.NO_CONTENT);
    		
    	}
    	
    	
    	@RequestMapping(value="/user/delete/all", method=RequestMethod.GET)
    	public ResponseEntity<User> deleteAllUsers()
    	{
    		userService.deleteAllUser();
    		return new ResponseEntity<User>(HttpStatus.NO_CONTENT);
    		
    	}
    

      

    大致访问:

    http://localhost:8080/gugua11/users

    http://localhost:8080/gugua11/user/1

    ......

    用火狐插件RESTClient,注意添加HTTP头字段:

    Content-Type: application/json

     

  • 相关阅读:
    机械设计手册
    如何在PADS的封装中做非金属化孔
    【Protle99SE】PCB中各层的含义【小汇】
    Stm32时钟分析
    头文件为什么要加#ifndef #define #endif
    android adb常用指令
    安装 SQLManagementStudio_x86_CHS(SQL Server Management Studio) 老提示重启的解决办法
    SQL 2008下载地址以及全新安装详细过程
    【原创】pads2007 Layout 电气连接性检查过孔显示错误
    十款最具发展前景机器人
  • 原文地址:https://www.cnblogs.com/achengmu/p/9157142.html
Copyright © 2011-2022 走看看