JAVA annotationÈëÃÅ

JAVA annotationÈëÃÅ 
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Ò». ×î³£¼ûµÄannotation
@Override:ÓÃÔÚ·½·¨Ö®ÉÏ£¬ÓÃÀ´¸æËß±ðÈËÕâÒ»¸ö·½·¨ÊǸÄд¸¸ÀàµÄ
@Deprecated:½¨Òé±ðÈ˲»ÒªÊ¹ÓþɵÄAPIµÄʱºòÓõÄ,±àÒëµÄʱºò»áÓòúÉú¾¯¸æÐÅÏ¢,¿ÉÒÔÉ趨ÔÚ³ÌÐòÀïµÄËùÓеÄÔªËØÉÏ.
@SuppressWarnings:ÔÝʱ°ÑһЩ¾¯¸æÐÅÏ¢ÏûÏ¢¹Ø±Õ
@Entity:±íʾ¸ÃÀàÊǿɳ־û¯µÄÀà
 
¶þ. Éè¼ÆÒ»¸ö×Ô¼ºµÄAnnotation
      ÏÈ¿´´úÂëÔÙ½²»°
1. Ö»ÓÐÒ»¸ö²ÎÊýµÄAnnotationʵÏÖ
 
package chb.test.annotation;
import java.lang.annotation.Documented;
import java.lang.annotation.ElementType;
import java.lang.annotation.Retention;
import java.lang.annotation.RetentionPolicy;
import java.lang.annotation.Target;
@Target(ElementType.TYPE)
@Retention(RetentionPolicy.RUNTIME)
@Documented
public @interface MyAnnotation1 {
String value();
} 
 
2. ÓÐÁ½¸ö²ÎÊýµÄAnnotationʵÏÖ
 
package chb.test.annotation;
import java.lang.annotation.Documented;
import java.lang.annotation.ElementType;
import java.lang.annotation.Retention;
import java.lang.annotation.RetentionPolicy;
import java.lang.annotation.Target;
@Target(ElementType.METHOD)
@Retention(RetentionPolicy.RUNTIME)
@Documented
public @interface MyAnnotation2 {
String description();
boolean isAnnotation();
} 
 
3. AnnotationʵÑéÀà
 
package chb.test.annotation;
@MyAnnotation1("this is annotation1")
public class AnnotationDemo {
@MyAnnotation2(description="this is annotation2",isAnnotation=true)
public void sayHello(){
System.out.println("hello world!");
}
} 
 
4.Annotation²âÊÔ˵Ã÷Àà
 
package chb.test.annotation;
import java.lang.reflect.Method;
import org.junit.Test;
public class TestAnnotation {
@Test
public void test() throws ClassNotFoundException, SecurityException, NoSuchMethodException{
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