[英]Spring AOP Pointcut expression for annotated field
是否可以捕獲具有特定注釋的任何字段? 我的最終目標是在該字段中注入一個值,但目前我的切入點是錯誤的(不確定正確的語法)。
@Pointcut("execution(* *(..)) && @annotation(com.mycompany.MyAnnotation)")
private void annotatedField(){}
@Around("annotatedField()")
public Object injectValue(final ProceedingJoinPoint proceedingJoinPoint) throws Throwable {}
我相信切入點是使用注釋聲明任何方法。 我想改變它說任何領域。
我認為你應該遵循Sotirios Delimanolis的建議,並盡可能使用Spring on-board手段。 如果那時你仍然認為它們不夠並且絕對想要使用方面來實現你的想法,你可以在Spring中使用AspectJ而不是Spring AOP並利用get()
和set()
等切入點的全部功能來攔截read /在類成員上編寫操作(靜態和非靜態)。 例如:
標記注釋:
package de.scrum_master.app;
import java.lang.annotation.ElementType;
import java.lang.annotation.Retention;
import java.lang.annotation.RetentionPolicy;
import java.lang.annotation.Target;
@Retention(RetentionPolicy.RUNTIME)
@Target(ElementType.FIELD)
public @interface MyAnnotation {}
司機申請:
應用程序讀取( toString()
)並寫入(構造函數,main方法)所有字段,其中包括帶注釋的status
字段。
package de.scrum_master.app;
public class Application {
private int id;
private String name;
@MyAnnotation private String status;
public Application(int id, String name, String status) {
this.id = id;
this.name = name;
this.status = status;
}
@Override
public String toString() {
return "Application [id=" + id + ", name=" + name + ", status=" + status + "]";
}
public static void main(String[] args) {
Application application = new Application(11, "AspectJ demo", "starting");
System.out.println(application);
application.id = 22;
application.name = "AspectJ field access demo";
application.status = "running";
System.out.println(application);
application.status = "shutting down";
System.out.println(application);
application.status = "stopped";
System.out.println(application);
}
}
方面:
package de.scrum_master.aspect;
import org.aspectj.lang.JoinPoint;
import org.aspectj.lang.annotation.Aspect;
import org.aspectj.lang.annotation.Before;
@Aspect
public class AnnotatedFieldAspect {
@Before("get(* *) && @annotation(de.scrum_master.app.MyAnnotation)")
public void interceptRead(JoinPoint thisJoinPoint) {
System.out.println(thisJoinPoint);
}
@Before("set(* *) && @annotation(de.scrum_master.app.MyAnnotation) && args(newValue)")
public void interceptWrite(JoinPoint thisJoinPoint, Object newValue) {
System.out.println(thisJoinPoint + " -> " + newValue);
}
}
控制台日志:
set(String de.scrum_master.app.Application.status) -> starting
get(String de.scrum_master.app.Application.status)
Application [id=11, name=AspectJ demo, status=starting]
set(String de.scrum_master.app.Application.status) -> running
get(String de.scrum_master.app.Application.status)
Application [id=22, name=AspectJ field access demo, status=running]
set(String de.scrum_master.app.Application.status) -> shutting down
get(String de.scrum_master.app.Application.status)
Application [id=22, name=AspectJ field access demo, status=shutting down]
set(String de.scrum_master.app.Application.status) -> stopped
get(String de.scrum_master.app.Application.status)
Application [id=22, name=AspectJ field access demo, status=stopped]
聲明:本站的技術帖子網頁,遵循CC BY-SA 4.0協議,如果您需要轉載,請注明本站網址或者原文地址。任何問題請咨詢:yoyou2525@163.com.