springboot 缓存@EnableCaching实例

class User {
 private Long id;
 private String name;
// setter getter
}

import javax.annotation.PostConstruct;
import org.springframework.cache.annotation.CacheEvict;
import org.springframework.cache.annotation.CachePut;
import org.springframework.cache.annotation.Cacheable;
import org.springframework.cache.annotation.EnableCaching;
import org.springframework.stereotype.Component;
/**
 * @author micro
 * @date 2017年8月2日
 * @description :
 */
@Component
@EnableCaching
public class UserDao {
 private Map<Long, User> userMap;
 @PostConstruct
 public void init() {
  //模拟数据库
  userMap = new HashMap<Long, User>();
  userMap.put(1L, new User(1L,"micro1"));
  userMap.put(2L, new User(2L, "micro2"));
 }
 
 @Cacheable("user")  // 注解key属性可以执行缓存对象user(可以理解为一个map)的key 
 public User getUser(Long userId) {
  System.out.println("查询数据库:userId ->" + userId);
  return userMap.get(userId);
 }
 
 @Cacheable(value = "nameCache", key = "#name")
 public User getUserByName(Long userId, String name) {
  System.out.println("查询数据库:userId ->" + userId);
  return userMap.get(userId);
 }
 
 @Cacheable("nameCache")
 public User getUserByName(String name) {
  System.out.println("查询数据库:userName : " + name);
  for (Long k : userMap.keySet()) {
   if (userMap.get(k).equals(name)) {
    return userMap.get(k);
   }
  }
  return null;
 }
 
 @CachePut("user") // 与Cacheable区别就是Cacheable先看缓存如果有，直接缓存换回，CachePut则是每次都会调用并且把返回值放到缓存
 public User getUser2(Long userId) {
  System.out.println("查询数据库:userId : " + userId);
  return userMap.get(userId);
 }
 
 @CacheEvict("user")
 public void removeFromCache(Long userId) {
  return ;
 }
}

@SpringBootApplication
public class CacheTest implements CommandLineRunner {
 @Autowired
 private UserDao userDao; 
 public static void main(String[] args) {
  new SpringApplication(CacheTest.class).run(args);
 } 
 @Override
 public void run(String... args) throws Exception {
  System.out.println("第一次查询");
  System.out.println(userDao.getUser(1L));
  System.out.println("第二次查询");
  System.out.println(userDao.getUser(1L));
  userDao.removeFromCache(1L);// 移除缓存
  System.out.println("第三次查询");
  userDao.getUser(1L);// 没有缓存了  
  System.out.println("--------");
  // 测试不同的key缓存
  userDao.getUserByName("micro1");
  userDao.getUserByName(1L, "micro1");// 指定了参数name 为key 此次读取缓存
 }
}