juneau-doc/docs/Topics/06.juneau-rest-server/17.Transforms.html

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Transforms

<p>
	The Juneau serializers and parsers can be configured on how to handle POJOs through the use of Transforms.
	(See {@doc juneau-marshall.Transforms Transforms})
</p>
<p>
	Transforms are associated serializers and parsers registered on a REST resource via the following:
</p>
<ul class='javatree'>
	<li class='ja'>{@link oaj.annotation.BeanConfig#beanFilters() BeanConfig(beanFilters)} - On class or methods. 
	<li class='ja'>{@link oaj.annotation.BeanConfig#pojoSwaps() BeanConfig(pojoSwaps)} - On class or methods. 
	<li class='jm'>{@link oajr.RestContextBuilder#beanFilters(Object...)} 
	<li class='jm'>{@link oajr.RestContextBuilder#pojoSwaps(Object...)} 
</ul>
<p class='bpcode w800'>
	<jc>// Servlet with transforms applied</jc>
	<ja>@Rest</ja>(
		...
	)
	<ja>@BeanConfig</ja>(
		pojoSwaps={
			<jc>// Calendars should be serialized/parsed as ISO8601 date-time strings</jc>
			TemporalCalendarSwap.IsoInstant.<jk>class</jk>,

			<jc>// Byte arrays should be serialized/parsed as BASE64-encoded strings</jc>
			ByteArraySwap.Base64.<jk>class</jk>
		},
		beanFilters={
			<jc>// Subclasses of MyInterface will be treated as MyInterface objects.</jc>
			<jc>// Bean properties not defined on that interface will be ignored.</jc>
			MyInterface.<jk>class</jk>
		}
	)
	<jk>public</jk> MyRestServlet <jk>extends</jk> BasicRestServlet {...}
</p>
<p>
	The programmatic equivalent to this is:
</p>
<p class='bpcode w800'>
	<jc>// Servlet with properties applied</jc>
	<ja>@Rest</ja>(...)
	<jk>public</jk> MyRestServlet <jk>extends</jk> BasicRestServlet {
	
		<jk>public</jk> MyRestServlet(RestContextBuilder builder) {
			
			builder
				.pojoSwaps(
					TemporalCalendarSwap.IsoInstant.<jk>class</jk>,
					ByteArraySwap.Base64.<jk>class</jk>
				) 
				.beanFilters(MyInterface.<jk>class</jk>);
		}
	}
</p>