正文
springboot使用异步查询数据
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主要适用于需要查询多种类型的数据，而且二者的参数没有关联的情况。
1、开启异步调用注解
2、创建抽象类，定义相关方法
/**
* @author：YZH
* time: 2019/8/8 12:16
* description: 建立抽象类，定义相关方法
**/
public abstract class BaseAdapt<T,Base>{
private Base base; public BaseAdapt(Base base){
this.base = base;
} /**
* 查询list数据（默认要实现）
* @return
*/
public abstract List<T>list(); /**
* 查询数量
* @return
*/
public int count(){return 0;} /**
* 返回单个对象V
* @return
*/
public T getT(){
return null;
} }
3、建立异步调用方法
@Component
public class DemoThread { @Async
public <T,Base> Future<T> getT(BaseAdapt<T,Base>baseAdapt) {
return new AsyncResult<>(baseAdapt.getT());
} @Async
public <T,Base> Future<List<T>> list(BaseAdapt<T,Base> baseAdapt){
return new AsyncResult<>(baseAdapt.list());
} @Async
public Future<Integer>count(BaseAdapt baseAdapt){
return new AsyncResult<>(baseAdapt.count());
}
}
4、建立一个dao类，模拟访问数据库
@Component
public class UserDao { public User getUser(){
User user = new User();
user.setName("测试");
user.setId(UUID.randomUUID().toString());
return user;
} public List<User>listUser(){
int num = new Random(1).nextInt(10);
System.out.println("随机生成："+num+"个user");
List<User>users = new ArrayList<>(num);
for (int i = 0; i < num; i++) {
User user = new User();
user.setId(UUID.randomUUID().toString());
user.setName("测试"+i);
users.add(user);
}
return users;
}
public int count(){
return new Random(1).nextInt(10);
}
}
5、调用
a、只实现默认方法，获取list数据
@Test
public void testAsync() throws InstantiationException, IllegalAccessException, ExecutionException, InterruptedException {
BaseAdapt<User,UserDao>baseAdapt = new BaseAdapt<User, UserDao>(userDao) {
@Override
public List<User> list() {
return userDao.listUser();
}
};
Future<List<User>> list = demoThread.list(baseAdapt);
Future<Integer> count = demoThread.count(baseAdapt);
List<User> users = list.get();
Integer integer = count.get();
System.out.println("总数："+integer);
for (User user : users) {
System.out.println(user);
}
}
b、新增查询数量
@Test
public void testAsync() throws InstantiationException, IllegalAccessException, ExecutionException, InterruptedException {
BaseAdapt<User,UserDao>baseAdapt = new BaseAdapt<User, UserDao>(userDao) {
@Override
public List<User> list() {
return userDao.listUser();
}
@Override
public int count() {
return userDao.count();
}
};
Future<List<User>> list = demoThread.list(baseAdapt);
Future<Integer> count = demoThread.count(baseAdapt);
List<User> users = list.get();
Integer integer = count.get();
System.out.println("总数："+integer);
for (User user : users) {
System.out.println(user);
}
}
