java注解

地址
`java

复制代码
/注解声明/

/**

• 水果名称注解
• @author peida
  
  /
  @Target(ElementType.FIELD)
  @Retention(RetentionPolicy.RUNTIME)
  @Documented
  public @interface FruitName {
  String value() default “”;
  }

/**

• 水果颜色注解
• @author peida
  
  /
  @Target(ElementType.FIELD)
  @Retention(RetentionPolicy.RUNTIME)
  @Documented
  public @interface FruitColor {
  /**
  • 颜色枚举
  • @author peida
    
    /
    public enum Color{ BULE,RED,GREEN};

    /**

  • 颜色属性
  • @return
    */
    Color fruitColor() default Color.GREEN;

}

/**

• 水果供应者注解
• @author peida
  
  /
  @Target(ElementType.FIELD)
  @Retention(RetentionPolicy.RUNTIME)
  @Documented
  public @interface FruitProvider {
  /**
  • 供应商编号
  • @return
    */
    public int id() default -1;

    /**

  • 供应商名称
  • @return
    */
    public String name() default “”;

    /**

  • 供应商地址
  • @return
    */
    public String address() default “”;
    }

/注解使用/

public class Apple {

@FruitName("Apple")
private String appleName;

@FruitColor(fruitColor=Color.RED)
private String appleColor;

@FruitProvider(id=1,name="陕西红富士集团",address="陕西省西安市延安路89号红富士大厦")
private String appleProvider;

public void setAppleColor(String appleColor) {
    this.appleColor = appleColor;
}
public String getAppleColor() {
    return appleColor;
}

public void setAppleName(String appleName) {
    this.appleName = appleName;
}
public String getAppleName() {
    return appleName;
}

public void setAppleProvider(String appleProvider) {
    this.appleProvider = appleProvider;
}
public String getAppleProvider() {
    return appleProvider;
}

public void displayName(){
    System.out.println("水果的名字是：苹果");
}

}

/***注解处理器***/

public class FruitInfoUtil {
public static void getFruitInfo(Class<?> clazz){

    String strFruitName=" 水果名称：";
    String strFruitColor=" 水果颜色：";
    String strFruitProvicer="供应商信息：";

    Field[] fields = clazz.getDeclaredFields();

    for(Field field :fields){
        if(field.isAnnotationPresent(FruitName.class)){
            FruitName fruitName = (FruitName) field.getAnnotation(FruitName.class);
            strFruitName=strFruitName+fruitName.value();
            System.out.println(strFruitName);
        }
        else if(field.isAnnotationPresent(FruitColor.class)){
            FruitColor fruitColor= (FruitColor) field.getAnnotation(FruitColor.class);
            strFruitColor=strFruitColor+fruitColor.fruitColor().toString();
            System.out.println(strFruitColor);
        }
        else if(field.isAnnotationPresent(FruitProvider.class)){
            FruitProvider fruitProvider= (FruitProvider) field.getAnnotation(FruitProvider.class);
            strFruitProvicer=" 供应商编号："+fruitProvider.id()+" 供应商名称："+fruitProvider.name()+" 供应商地址："+fruitProvider.address();
            System.out.println(strFruitProvicer);
        }
    }
}

}

/***输出结果***/
public class FruitRun {

/**
 * @param args
 */
public static void main(String[] args) {

    FruitInfoUtil.getFruitInfo(Apple.class);

}

}