我负责的模块，在执行我这边逻辑的时候，要给别人预留一个口，可以通知别人，我这边的逻辑执行了，就这么简单的一个功能，不能用springboot，很惭愧，我居然不会做了。
springboot的高度封装，已经让我变成了一个废物。
这个口，其实就是一个事件。下面举例三种Java事件的实现方式
- 抽象类
- jdk util中的Event，这个方式感觉并不那么友好
- springboot Event
模拟身体要撒尿、拉屎，大脑监听到信号的操作。
一、抽象类
先实现一个抽象类
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| public abstract class EventHandler {
public void beforePee() {
}
public void afterPee() {
}
public void beforeShit() {
}
public void afterShit() {
}
}
|
Body
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| public class Body {
private EventHandler eventHandler=new EventHandler() {
};
public void setEventHandler(EventHandler eventHandler) {
this.eventHandler = eventHandler;
}
public void bodyActivity() {
eventHandler.beforePee();
pee();
eventHandler.afterPee();
eventHandler.beforeShit();
shit();
eventHandler.afterShit();
}
private void pee() {
System.out.println("撒尿");
try {
Thread.sleep(1000);
} catch (InterruptedException e) {
e.printStackTrace();
}
}
private void shit() {
System.out.println("拉屎");
try {
Thread.sleep(1000);
} catch (InterruptedException e) {
e.printStackTrace();
}
}
}
|
大脑实现监听
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| public class HeadListener extends EventHandler {
@Override
public void beforePee() {
System.out.println("大脑监听到身体想撒尿");
}
@Override
public void afterPee() {
System.out.println("大脑监听到身体撒完尿");
}
@Override
public void beforeShit() {
System.out.println("大脑监听到身体想拉屎");
}
@Override
public void afterShit() {
System.out.println("大脑监听到身体拉完屎");
}
}
|
启动入口类
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| public class AbstractClassMain {
public static void main(String[] args) {
Body body =new Body();
body.setEventHandler(new HeadListener());
body.bodyActivity();
}
}
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输出结果
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| 大脑监听到身体想撒尿
撒尿
大脑监听到身体撒完尿
大脑监听到身体想拉屎
拉屎
大脑监听到身体拉完屎
|
不一定要用抽象类，其实接口本身也是一种实现方式
二、SpringBoot中的Event
事件
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| public class Event extends EventObject {
public Event(Object source) {
super(source);
}
}
public class BeforePee {
}
public class AfterPee {
}
public class BeforeShit {
}
public class AfterShit {
}
|
Body
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| @Component
public class Body {
@Autowired
private ApplicationContext context;
public void bodyActivity() {
context.publishEvent(new Event(new BeforePee()));
pee();
context.publishEvent(new Event(new AfterPee()));
context.publishEvent(new Event(new BeforeShit()));
shit();
context.publishEvent(new Event(new AfterShit()));
}
private void pee() {
System.out.println("撒尿");
try {
Thread.sleep(1000);
} catch (InterruptedException e) {
e.printStackTrace();
}
}
private void shit() {
System.out.println("拉屎");
try {
Thread.sleep(1000);
} catch (InterruptedException e) {
e.printStackTrace();
}
}
}
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大脑监听
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| @Component
public class HeadListener {
@EventListener
public void headListener(Event event) {
Object source = event.getSource();
if(source instanceof BeforePee) {
System.out.println("大脑监听到身体想撒尿");
}
if(source instanceof AfterPee) {
System.out.println("大脑监听到身体撒完尿");
}
if(source instanceof BeforeShit) {
System.out.println("大脑监听到身体想拉屎");
}
if(source instanceof AfterShit) {
System.out.println("大脑监听到身体拉完屎");
}
}
}
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配置Runner让Springboot项目启动后执行
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| @Component
public class ExecuteRunner implements CommandLineRunner {
@Autowired
private Body body;
@Override
public void run(String... args) throws Exception {
body.bodyActivity();
}
}
|
运行结果跟上面相同
