在spring-boot中，引入非常多的新特性，简化了spring中繁琐，臃肿的开发方式

组合注解

使用组合注解，通过其名称，就可以非常容易知道其意义，提高代码的可读性

@RestController=@Controller+@ResponseBody

@GetMapping=@RequestMapping(method = RequestMethod.GET)

http客户端

spring-boot提供了专门用于restApi调用的模板类RestTemplate，该模板类使用了单例的设计模式，底层也实现了线程池,http长连接的特性，开发人员非常方便就可以开发出高性能的http客户端程序

列子

spring-cloud-consumer-user工程

UserController.java

package com.example.demo.controller;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.web.bind.annotation.GetMapping;
import org.springframework.web.bind.annotation.PathVariable;
import org.springframework.web.bind.annotation.RequestMapping;
import org.springframework.web.bind.annotation.RestController;
import org.springframework.web.client.RestTemplate;
import com.example.demo.model.User;
@RestController
@RequestMapping(value="/user")
public class UserController {
    @Autowired
    private RestTemplate restTemplate;
    @GetMapping(value="/get/{id}")
    public User get(@PathVariable String id){
        return restTemplate.getForObject("http://localhost:8080/user/get?id="+id, User.class);
    }
}

CoreConfig.java

package com.example.demo.config;
import org.springframework.context.annotation.Bean;
import org.springframework.context.annotation.Configuration;
import org.springframework.web.client.RestTemplate;
@Configuration
public class CoreConfig {
    @Bean
    public RestTemplate restTemplateBean(){
        return new RestTemplate();
    }
}

User.java

package com.example.demo.model;
import java.util.Date;
public class User {
    private String id;
    private String userName;
    private int age;
    private Date birthday;
    public String getId() {
        return id;
    }
    public void setId(String id) {
        this.id = id;
    }
    public String getUserName() {
        return userName;
    }
    public void setUserName(String userName) {
        this.userName = userName;
    }
    public int getAge() {
        return age;
    }
    public void setAge(int age) {
        this.age = age;
    }
    public Date getBirthday() {
        return birthday;
    }
    public void setBirthday(Date birthday) {
        this.birthday = birthday;
    }
}

application.properties

server.port=8081

spring-cloud-provider工程

UserController.java

package com.dennis.controller;
import java.util.HashMap;
import java.util.Map;
import org.springframework.web.bind.annotation.GetMapping;
import org.springframework.web.bind.annotation.RequestMapping;
import org.springframework.web.bind.annotation.ResponseBody;
import org.springframework.web.bind.annotation.RestController;

import com.dennis.model.User;
@RestController
@RequestMapping(value="/user")
public class UserController {
    private Map<String, User> umap = new HashMap();
    public UserController(){
        umap.put("1", new User("1", "xiaoming", 30));
        umap.put("2", new User("2", "xiaohong", 20));
        umap.put("3", new User("3", "zhangsan", 80));
        umap.put("4", new User("4", "lisi", 10));
        umap.put("5", new User("5", "wangwu", 22));
    }
    @GetMapping(value="/get")
    @ResponseBody
    public User get(String id){
        return umap.get(id);
    }
}