项目结构如下：

SpringCloudOrderApplication类

package com.example.demo;

import org.springframework.boot.SpringApplication;
import org.springframework.boot.autoconfigure.SpringBootApplication;
import org.springframework.cloud.netflix.eureka.EnableEurekaClient;
import org.springframework.context.annotation.Bean;
import org.springframework.web.client.RestTemplate;

@SpringBootApplication
@EnableEurekaClient
public class SpringCloudOrderApplication {

  @Bean	//必须new 一个RestTemplate并放入spring容器当中,否则启动时报错
  public RestTemplate restTemplate() {
    return new RestTemplate();
  }

  public static void main(String[] args) {
    SpringApplication.run(SpringCloudOrderApplication.class, args);
  }

OrderController类

package com.example.demo.controller;

import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.beans.factory.annotation.Value;
import org.springframework.web.bind.annotation.GetMapping;
import org.springframework.web.bind.annotation.PathVariable;
import org.springframework.web.bind.annotation.RestController;
import org.springframework.web.client.RestTemplate;

import com.example.demo.entity.User;

@RestController
public class OrderController {
  @Autowired
  private RestTemplate restTemplate;
  
  //获取application.yml里相应节点的值
  @Value("${user.userServicePath}")
  private String userServicePath;

  @GetMapping("/order/{id}")
  public User findById(@PathVariable Long id) {
    return this.restTemplate.getForObject(this.userServicePath + id, User.class);
  }
}

User类

package com.example.demo.entity;

import java.math.BigDecimal;

public class User {
  private Long id;

  private String username;

  private String name;

  private Short age;

  private BigDecimal balance;

  public Long getId() {
    return this.id;
  }

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

  public String getUsername() {
    return this.username;
  }

  public void setUsername(String username) {
    this.username = username;
  }

  public String getName() {
    return this.name;
  }

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

  public Short getAge() {
    return this.age;
  }

  public void setAge(Short age) {
    this.age = age;
  }

  public BigDecimal getBalance() {
    return this.balance;
  }

  public void setBalance(BigDecimal balance) {
    this.balance = balance;
  }

}

application.yml配置

spring:
  application:
    name: spring-cloud-order    #微服务的名称
server:
  port: 7901  #微服务端口号
user: 
  userServicePath: http://localhost:7900/user/    #用户微服务的URL地址
eureka:
  client:
    healthcheck:
      enabled: true   # 开启健康检查
    serviceUrl:
      defaultZone: http://user:123456@localhost:8761/eureka   #服务eureka的URL地址
  instance:
    prefer-ip-address: true

Pom.xml配置

<?xml version="1.0" encoding="UTF-8"?>
<project xmlns="http://maven.apache.org/POM/4.0.0" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
	xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 http://maven.apache.org/xsd/maven-4.0.0.xsd">
	<modelVersion>4.0.0</modelVersion>

	<groupId>com.example.demo</groupId>
	<artifactId>spring-cloud-order</artifactId>
	<version>0.0.1-SNAPSHOT</version>
	<packaging>war</packaging>

	<name>spring-cloud-order</name>
	<description>spring-cloud-order</description>

	<parent>
		<groupId>org.springframework.boot</groupId>
		<artifactId>spring-boot-starter-parent</artifactId>
		<version>1.4.1.RELEASE</version>
	</parent>

	<properties>
		<!-- 文件拷贝时的编码 -->  
		<project.build.sourceEncoding>UTF-8</project.build.sourceEncoding>
		<project.reporting.outputEncoding>UTF-8</project.reporting.outputEncoding>
		  <!-- 编译时的编码 -->  
        <maven.compiler.encoding>UTF-8</maven.compiler.encoding>  
        <!-- jdk版本 -->  
		<java.version>1.8</java.version>
	</properties>

	<dependencies>
		<dependency>
			<groupId>org.springframework.boot</groupId>
			<artifactId>spring-boot-starter-web</artifactId>
		</dependency>
		<!-- 注册中心 -->
		<dependency>
			<groupId>org.springframework.cloud</groupId>
			<artifactId>spring-cloud-starter-eureka</artifactId>
		</dependency>
		<!-- 这个库让我们可以访问应用的很多信息,包括:/env、/info、/metrics、/health等 -->
		<dependency>
			<groupId>org.springframework.boot</groupId>
			<artifactId>spring-boot-starter-actuator</artifactId>
		</dependency>
		<!-- 用于热部署 -->
		<dependency>
			<groupId>org.springframework.boot</groupId>
			<artifactId>spring-boot-devtools</artifactId>
		</dependency>		
	</dependencies>
	<dependencyManagement>
		<dependencies>
		<!-- 版本依赖管理，故之后添加依赖无需指定version -->
			<dependency>
				<groupId>org.springframework.cloud</groupId>
				<artifactId>spring-cloud-dependencies</artifactId>
				<version>Camden.SR2</version>
				<type>pom</type>
				<scope>import</scope>
			</dependency>
		</dependencies>
	</dependencyManagement>

	<build>
		<plugins>
		<!-- 用以为integration-test提供支持。 -->
			<plugin>
				<groupId>org.springframework.boot</groupId>
				<artifactId>spring-boot-maven-plugin</artifactId>
			</plugin>
		</plugins>
	</build>
</project>

注意，要是创建的项目报错，请点击项目右键：Maven----->Update Project

勾选Force Update of Snapshots/Releases即可