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Function Toggles Java Annotations

How can I enable jQuery java annotations?

Simple switch function: - if (turn on the switch) do x

Spring allows you to use "profiles" to switch beans.

I use them and they are beautiful, but I would like to switch annotation to field or classes. How can i do this?

Use the case, I have a class that has jpa annotations. I want to tag through the configuration that some @transient fields when in certain environments.

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aspectj spring .

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UPDATE

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package org.foo.bar;

import org.springframework.context.ApplicationContext;
import org.springframework.context.support.ClassPathXmlApplicationContext;

public class Main {

    public static void main(String[] args) {
        ApplicationContext context = new ClassPathXmlApplicationContext("/applicationContext.xml");
        MyClass myObj = context.getBean("myObj", MyClass.class);

        System.out.println(myObj);
        System.out.println(myObj.getValue1());
        System.out.println(myObj.getValue2());
    }

}


package org.foo.bar;

public class MyClass {

    @MyAnn("annotated-field-1")
    private String field1;
    private String field2;

    @MyAnn("annotated-method-1")
    public String getValue1() {
        String value = null;
        try {
            MyAnn ann = getClass().getDeclaredMethod("getValue1").getAnnotation(MyAnn.class);
            if(ann != null) {
                value = ann.value();
            }
        } catch (NoSuchMethodException e) {
            throw new RuntimeException(e);
        }
        return value;
    }

    public String getValue2() {
        String value = null;
        try {
            MyAnn ann = getClass().getDeclaredMethod("getValue2").getAnnotation(MyAnn.class);
            if(ann != null) {
                value = ann.value();
            }
        } catch (NoSuchMethodException e) {
            throw new RuntimeException(e);
        }
        return value;
    }

    @Override
    public String toString() {
        String field1 = null;
        try {
            MyAnn ann = getClass().getDeclaredField("field1").getAnnotation(MyAnn.class);
            if(ann != null) {
                field1 = ann.value();
            }
        } catch (NoSuchFieldException e) {
            throw new RuntimeException(e);
        }

        String field2 = null;
        try {
            MyAnn ann = getClass().getDeclaredField("field2").getAnnotation(MyAnn.class);
            if(ann != null) {
                field2 = ann.value();
            }
        } catch (NoSuchFieldException e) {
            throw new RuntimeException(e);
        }

        StringBuilder sb = new StringBuilder();
        sb.append("MyClass");
        sb.append("{field1='").append(field1).append('\'');
        sb.append(", field2='").append(field2).append('\'');
        sb.append('}');
        return sb.toString();
    }
}


package org.foo.bar;

import java.lang.annotation.Documented;
import java.lang.annotation.ElementType;
import java.lang.annotation.Inherited;
import java.lang.annotation.Retention;
import java.lang.annotation.RetentionPolicy;
import java.lang.annotation.Target;

@Retention(RetentionPolicy.RUNTIME)
@Inherited
@Documented
@Target({ElementType.FIELD, ElementType.METHOD})
public @interface MyAnn {

    String value();

}


<?xml version="1.0" encoding="UTF-8"?>
<beans xmlns="http://www.springframework.org/schema/beans"
       xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
       xmlns:context="http://www.springframework.org/schema/context"
       xsi:schemaLocation="http://www.springframework.org/schema/beans http://www.springframework.org/schema/beans/spring-beans.xsd http://www.springframework.org/schema/context http://www.springframework.org/schema/context/spring-context-3.1.xsd">

    <context:load-time-weaver />

    <bean id="myObj" class="org.foo.bar.MyClass" />

</beans>


package org.foo.bar;

public aspect ToggleAnnotationAspect {

    declare @field : private String org.foo.bar.MyClass.field1 : -@MyAnn;
    declare @field : private String org.foo.bar.MyClass.field2 : @MyAnn("annotated-field-2");

    declare @method : public String org.foo.bar.MyClass.getValue2() : @MyAnn("annotated-method-2");

}

META-INF/aop.xml

<?xml version="1.0"?>

<aspectj>
    <aspects>
        <aspect name="org.foo.bar.ToggleAnnotationAspect"/>
    </aspects>
</aspectj>


java -javaagent:spring-instrument-3.1.3.RELEASE.jar \
     -classpath app1.jar;<rest_of_cp> org.foo.bar.Main


MyClass{field1='annotated-field-1', field2='null'}
annotated-method-1
null

​​

java -javaagent:spring-instrument-3.1.3.RELEASE.jar \
     -classpath app1.jar;app1-aspects.jar;<rest_of_cp> org.foo.bar.Main


MyClass{field1='null', field2='annotated-field-2'}
annotated-method-1
annotated-method-2

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+3

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, , . ORM JPA (, Hibernate).

ORM , , Hibernate, Interceptor , hibernate.ejb.interceptor JPA, .

, , , (, @ConditionalTransiet), - , , , enviornment, onLoad onSave Object.

+3

, . , , - JPA ( persistence). , .

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+1

( ):

@Profile("active")
privileged aspect AddField {
    private String MyClass.name;
}

@Profile("inactive")
privileged aspect AddFieldTransient {
    @Transient
    private String MyClass.name;
}

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+1

Hibernate , , XML . .

JPA, orm.xml . . http://docs.jboss.org/hibernate/annotations/3.5/reference/en/html/xml-overriding.html .

In your case, if you use metadata-complete="true", all metadata is taken from the orm.xml file, not from annotations. Then you can use two different orm.xml.

<entity class="Administration" access="PROPERTY" metadata-complete="true">
    <attributes>
       <basic name="status"/>
       <basic name="optional">
     </attributes>


<entity class="Administration" access="PROPERTY" metadata-complete="true">
    <attributes>
       <basic name="status"/>
       <!-- omitted optional property -->
     </attributes>

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