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package org.apache.juneau.swap;

import org.apache.juneau.annotation.*;

/**
 * Identifies a class as being a surrogate class.
 *
 * 
 * Surrogate classes are used in place of other classes during serialization.
 * 
For example, you may want to use a surrogate class to change the names or order of bean properties on a bean.
 *
 * 

 * This interface has no methods to implement.
 * 
It's simply used by the framework to identify the class as a surrogate class when specified as a swap.
 *
 * 

 * The following is an example of a surrogate class change changes a property name:
 * 

 * 	public class MySurrogate implements Surrogate {
 *
 * 		// Public constructor that wraps the normal object during serialization.
 * 		public MySurrogate(NormalClass object) {...}
 *
 * 		// Public no-arg constructor using during parsing.
 * 		// Not required if only used during serializing.
 * 		public MySurrogate() {...}
 *
 * 		// Public method that converts surrogate back into normal object during parsing.
 * 		// The method name can be anything (e.g. "build", "create", etc...).
 * 		// Not required if only used during serializing.
 * 		public NormalClass unswap() {...}
 * 	}
 * 
 *
 * 
 * Surrogate classes are associated with serializers and parsers using the {@link org.apache.juneau.BeanContext.Builder#swaps(Class...)}
 * method.
 * 

 * 	JsonSerializer serializer = JsonSerializer
 * 		.create()
 * 		.swaps(MySurrogate.class)
 * 		.build();
 *
 * 	JsonParser parser = JsonParser
 * 		.create()
 * 		.swaps(MySurrogate.class)
 * 		.build();
 * 
 *
 * 
 * Surrogates can also be associated using the {@link Swap @Swap} annotation.
 * 

 * 	@Swap(MySurrogate.class)
 * 	public class NormalClass {...}
 * 
 *
 * 
 * On a side note, a surrogate class is functionally equivalent to the following {@link ObjectSwap}
 * implementation:
 * 

 * 	public class MySurrogate extends ObjectSwap<NormalClass,MySurrogate> {
 * 		public MySurrogate swap(NormalClass object) throws SerializeException {
 * 			return new MySurrogate(object);
 * 		}
 * 		public NormalClass unswap(MySurrogate surrogate, ClassMeta<?> hint) throws ParseException {
 * 			return surrogate.unswap();
 * 		}
 * 	}
 * 
 *
 * See Also:

 * 	Surrogate Classes
 * 	
Swaps
 * 
 */
public interface Surrogate {}