Package org.apache.juneau.swap

Class MapSwap<T>

java.lang.Object

org.apache.juneau.swap.ObjectSwap<T,JsonMap>

org.apache.juneau.swap.MapSwap<T>

Type Parameters:

T - The normal form of the class.

public abstract class MapSwap<T>
extends ObjectSwap<T,JsonMap>

Abstract subclass for object swaps that swap objects for object maps.

Example:

// A swap that converts beans into generic maps. public class MyBeanSwap extends MapSwap<byte[]> { @Override public JsonMap swap(BeanSession session, MyBean bean) throws Exception { return JsonMap.of("foo", bean.getFoo()); } @Override public MyBean unswap(BeanSession session, JsonMap map, ClassMeta<?> hint) throws Exception { return new MyBean(map.get("foo")); } } // Use it to serialize a byte array. WriterSerializer serializer = JsonSerializer.create().simple().swaps(MyBeanSwap.class).build(); String json = serializer.serialize(new MyBean("bar")); // Produces "{foo:'bar'}"

See Also:

• Swaps

Field Summary

Fields inherited from class org.apache.juneau.swap.ObjectSwap

NULL

Constructor Summary

Constructors

Constructor	Description
MapSwap()

Method Summary

Modifier and Type	Method	Description
JsonMap	swap(BeanSession session, T o)	If this transform is to be used to serialize non-serializable objects, it must implement this method.
T	unswap(BeanSession session, JsonMap f, ClassMeta<?> hint)	If this transform is to be used to reconstitute objects that aren't true Java beans, it must implement this method.

Methods inherited from class org.apache.juneau.swap.ObjectSwap

forMediaTypes, forMediaTypes, getNormalClass, getSwapClass, getSwapClassMeta, isNormalObject, isSwappedObject, match, swap, toString, unswap, withTemplate, withTemplate

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, wait, wait, wait

Constructor Details

MapSwap

public MapSwap()

Method Details

swap

public JsonMap swap(BeanSession session,
 T o)
             throws Exception

Description copied from class: ObjectSwap

If this transform is to be used to serialize non-serializable objects, it must implement this method.

The object must be converted into one of the following serializable types:

• String
• Number
• Boolean
• Collection containing anything on this list.
• Map containing anything on this list.
• A java bean with properties of anything on this list.
• An array of anything on this list.

Overrides:

swap in class ObjectSwap<T,JsonMap>

Parameters:

session - The bean session to use to get the class meta. This is always going to be the same bean context that created this swap.

o - The object to be transformed.

Returns:

The transformed object.

Throws:

Exception - If a problem occurred trying to convert the output.

unswap

public T unswap(BeanSession session,
 JsonMap f,
 ClassMeta<?> hint)
         throws Exception

Description copied from class: ObjectSwap

If this transform is to be used to reconstitute objects that aren't true Java beans, it must implement this method.

Overrides:

unswap in class ObjectSwap<T,JsonMap>

Parameters:

session - The bean session to use to get the class meta. This is always going to be the same bean context that created this swap.

f - The transformed object.

hint - If possible, the parser will try to tell you the object type being created. For example, on a serialized date, this may tell you that the object being created must be of type GregorianCalendar.
This may be null if the parser cannot make this determination.

Returns:

The narrowed object.

Throws:

Exception - If this method is not implemented.