17.7. Maps of JAXB Objects

RESTEasy automatically marshals maps of JAXB objects to and from XML, JSON, Fastinfoset, and other JAXB mappers. Your parameter or method return type must be generic, with a String as the key and the JAXB object's type.

@XmlRootElement(namespace = "http://foo.com")
public static class Foo
{
   @XmlAttribute
   private String name;

   public Foo()
   {
   }

   public Foo(String name)
   {
      this.name = name;
   }

   public String getName()
   {
      return name;
   }
}

@Path("/map")
public static class MyResource
{
   @POST
   @Produces("application/xml")
   @Consumes("application/xml")
   public Map<String, Foo> post(Map<String, Foo> map)
   {
      Assert.assertEquals(2, map.size());
      Assert.assertNotNull(map.get("bill"));
      Assert.assertNotNull(map.get("monica"));
      Assert.assertEquals(map.get("bill").getName(), "bill");
      Assert.assertEquals(map.get("monica").getName(), "monica");
      return map;
   }
 }

This resource publishes and receives JAXB objects within a map. By default, they are wrapped in a map element in the default namespace. Each map element has zero or more entry elements with a key attribute.

 <map>
<entry key="bill" xmlns="http://foo.com">
    <foo name="bill"/>
</entry>
<entry key="monica" xmlns="http://foo.com">
    <foo name="monica"/>
</entry>
 </map>

You can change the namespace URI, namespace prefix and map, entry, and key element and attribute names by using the @org.jboss.resteasy.annotations.providers.jaxb.WrappedMap annotation on a parameter or method.

 @Target({ElementType.PARAMETER, ElementType.METHOD})
 @Retention(RetentionPolicy.RUNTIME)
 public @interface WrappedMap
 {
/**
 * map element name
 */
String map() default "map";

/**
 * entry element name *
 */
String entry() default "entry";

/**
 * entry's key attribute name
 */
String key() default "key";

String namespace() default "";

String prefix() default "";
 }

So, to output the following XML:

 <hashmap>
<hashentry hashkey="bill" xmlns:foo="http://foo.com">
    <foo:foo name="bill"/>
</hashentry>
 </map>

We would use the @WrappedMap annotation as follows:

@Path("/map")
public static class MyResource
{
   @GET
   @Produces("application/xml")
   @WrappedMap(map="hashmap", entry="hashentry", key="hashkey")
   public Map<String, Foo> get()
   {
      ...
      return map;
   }

17.7.1. JSON and JAXB maps

RESTEasy supports the use of maps with JSON. It encloses returned JAXB objects within simple JSON maps. For example:

   @XmlRootElement
@XmlAccessorType(XmlAccessType.FIELD)
public static class Foo
{
   @XmlAttribute
   private String test;

   public Foo()
   {
   }

   public Foo(String test)
   {
      this.test = test;
   }

   public String getTest()
   {
      return test;
   }

   public void setTest(String test)
   {
      this.test = test;
   }
}

This a List or array of this Foo class would be represented in JSON like this:

 { "entry1" : {"foo":{"@test":"bill"}}, "entry2" : {"foo":{"@test":"monica}"}}}

It also expects this format for input