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// *  http://www.apache.org/licenses/LICENSE-2.0                                                                             *
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package org.apache.juneau.json.annotation;

import static java.lang.annotation.ElementType.*;
import static java.lang.annotation.RetentionPolicy.*;

import java.lang.annotation.*;

import org.apache.juneau.annotation.*;

/**
 * Annotation for specifying various JSON options for the JSON serializers and parsers.
 *
 * 
 * Can be used in the following locations:
 * 

 * 	Marshalled classes/methods/fields.
 * 	
@Rest-annotated classes and @RestOp-annotated methods when an {@link #on()} value is specified.
 * 
 *
 * 
 * Can be used for the following:
 * 

 * 	
 * 		Wrap bean instances inside wrapper object (e.g. {'wrapperAttr':bean}).
 * 
 *
 * See Also:

 * 	JSON Details

 * 
 */
@Documented
@Target({TYPE,METHOD,FIELD})
@Retention(RUNTIME)
@Inherited
@Repeatable(JsonAnnotation.Array.class)
@ContextApply(JsonAnnotation.Apply.class)
public @interface Json {

	/**
	 * Dynamically apply this annotation to the specified classes/methods/fields.
	 *
	 * 
	 * Used in conjunction with {@link org.apache.juneau.BeanContext.Builder#applyAnnotations(Class...)} to dynamically apply an annotation to an existing class/method/field.
	 * It is ignored when the annotation is applied directly to classes/methods/fields.
	 *
	 * 
Valid patterns:
	 * 
	 *  Classes:
	 * 		
	 * 			Fully qualified:
	 * 				
	 * 					"com.foo.MyClass"
	 * 				
	 * 			
Fully qualified inner class:
	 * 				
	 * 					"com.foo.MyClass$Inner1$Inner2"
	 * 				
	 * 			
Simple:
	 * 				
	 * 					"MyClass"
	 * 				
	 * 			
Simple inner:
	 * 				
	 * 					"MyClass$Inner1$Inner2"
	 * 					
"Inner1$Inner2"
	 * 					
"Inner2"
	 * 				
	 * 		
	 * 	
Methods:
	 * 		
	 * 			Fully qualified with args:
	 * 				
	 * 					"com.foo.MyClass.myMethod(String,int)"
	 * 					
"com.foo.MyClass.myMethod(java.lang.String,int)"
	 * 					
"com.foo.MyClass.myMethod()"
	 * 				
	 * 			
Fully qualified:
	 * 				
	 * 					"com.foo.MyClass.myMethod"
	 * 				
	 * 			
Simple with args:
	 * 				
	 * 					"MyClass.myMethod(String,int)"
	 * 					
"MyClass.myMethod(java.lang.String,int)"
	 * 					
"MyClass.myMethod()"
	 * 				
	 * 			
Simple:
	 * 				
	 * 					"MyClass.myMethod"
	 * 				
	 * 			
Simple inner class:
	 * 				
	 * 					"MyClass$Inner1$Inner2.myMethod"
	 * 					
"Inner1$Inner2.myMethod"
	 * 					
"Inner2.myMethod"
	 * 				
	 * 		
	 * 	
Fields:
	 * 		
	 * 			Fully qualified:
	 * 				
	 * 					"com.foo.MyClass.myField"
	 * 				
	 * 			
Simple:
	 * 				
	 * 					"MyClass.myField"
	 * 				
	 * 			
Simple inner class:
	 * 				
	 * 					"MyClass$Inner1$Inner2.myField"
	 * 					
"Inner1$Inner2.myField"
	 * 					
"Inner2.myField"
	 * 				
	 * 		
	 * 	
A comma-delimited list of anything on this list.
	 * 
	 *
	 * See Also:

	 * 	Dynamically Applied Annotations
	 * 
	 *
	 * @return The annotation value.
	 */
	String[] on() default {};

	/**
	 * Dynamically apply this annotation to the specified classes.
	 *
	 * 
	 * Identical to {@link #on()} except allows you to specify class objects instead of a strings.
	 *
	 * 
See Also:

	 * 	Dynamically Applied Annotations
	 * 
	 *
	 * @return The annotation value.
	 */
	Class[] onClass() default {};

	/**
	 * Wraps beans in a JSON object with the specified attribute name.
	 *
	 * 
	 * Applies only to {@link ElementType#TYPE}.
	 *
	 * 

	 * This annotation can be applied to beans as well as other objects serialized to other types (e.g. strings).
	 *
	 * 
Example:
	 * 
	 * 	@Json(wrapperAttr="myWrapper")
	 * 	public class MyBean {
	 * 		public int f1 = 123;
	 * 	}
	 * 
	 *
	 * 
	 * Without the @Json annotations, serializing this bean as JSON would have produced the following...
	 * 

	 * 	{
	 * 		f1: 123
	 * 	}
	 * 
	 *
	 * 
	 * With the annotations, serializing this bean as JSON produces the following...
	 * 

	 * 	{
	 * 		myWrapper: {
	 * 			f1: 123
	 * 		}
	 * 	}
	 * 
	 *
	 * @return The annotation value.
	 */
	String wrapperAttr() default "";
}