juneau-doc/docs/Topics/06.juneau-rest-server/13.Serializers.html

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Serializers

<p>
	REST resources use the {@link oaj.serializer.Serializer} API for defining serializers for 
	serializing response POJOs.
</p>
<p>
	The servlet will pick which serializer to use by matching the request <l>Accept</l> header with the
	media types defined through the {@link oaj.serializer.Serializer#getMediaTypeRanges()} method.
</p>
<p>
	Serializers can be associated with REST servlets in the following ways:
</p>
<ul class='javatree'>
	<li class='ja'>
		{@link oajr.annotation.Rest#serializers() Rest(serializers)} 
		- Annotation on resource Java class.
	<li class='ja'>
		{@link oajr.annotation.RestMethod#serializers() RestMethod(serializers)} 
		- Annotation on resource Java method.
	<li class='jf'>
		{@link oajr.RestContext#REST_serializers} 
		- Programmatic.
</ul>
<p>
	The following are all equivalent ways of defining serializers used by a resource:
</p> 		
<p class='bpcode w800'>
	<jc>// Option #1 - Defined via annotation.</jc>
	<ja>@Rest</ja>(serializers={JsonSerializer.<jk>class</jk>, XmlSerializer.<jk>class</jk>})
	<jk>public class</jk> MyResource {
		
		<jc>// Option #2 - Defined via builder passed in through resource constructor.</jc>
			<jk>public</jk> MyResource(RestContextBuilder builder) <jk>throws</jk> Exception {
			
			<jc>// Using method on builder.</jc>
			builder.serializers(JsonSerializer.<jk>class</jk>, XmlSerializer.<jk>class</jk>);

			<jc>// Same, but use pre-instantiated parsers.</jc>
			builder.serializers(JsonSerializer.<jsf>DEFAULT</jsf>, XmlSerializer.<jsf>DEFAULT</jsf>);

			<jc>// Same, but using property.</jc>
			builder.set(<jsf>REST_serializers</jsf>, JsonSerializer.<jk>class</jk>, XmlSerializer.<jk>class</jk>);
		}

		<jc>// Option #3 - Defined via builder passed in through init method.</jc>
		<ja>@RestHook</ja>(<jsf>INIT</jsf>)
		<jk>public void</jk> init(RestContextBuilder builder) <jk>throws</jk> Exception {
			builder.serializers(JsonSerializer.<jk>class</jk>, XmlSerializer.<jk>class</jk>);
		}

		<jc>// Override at the method level.</jc>
		<ja>@RestMethod</ja>(serializers={HtmlSerializer.<jk>class</jk>})
		<jk>public</jk> MyPojo myMethod() {
			<jc>// Return a POJO to be serialized.</jc>
			<jk>return new</jk> MyPojo(); 
		}
	}
</p>

<ul class='seealso'>
	<li class='jf'>{@link oajr.RestContext#REST_serializers}
</ul>