Using JAXB to unmarshal/marshal a List<String>

Question

I'm trying to create a very simple REST server. I just have a test method that will return a List of Strings. Here's the code:

  @GET @Path("/test2") public List test2(){     List list=new Vector();     list.add("a");     list.add("b");     return list; }  

It gives the following error:

 SEVERE: A message body writer for Java type, class java.util.Vector, and MIME media type, application/octet-stream, was not found 

I was hoping JAXB had a default setting for simple types like String, Integer, etc. I guess not. Here's what I imagined:

 <Strings>   <String>a</String>   <String>b</String> </Strings> 

What's the easiest way to make this method work?

Answer 1

I used @LiorH's example and expanded it to:

  @XmlRootElement(name="List") public class JaxbList<T>{     protected List<T> list;      public JaxbList(){}      public JaxbList(List<T> list){         this.list=list;     }      @XmlElement(name="Item")     public List<T> getList(){         return list;     } }  

Note, that it uses generics so you can use it with other classes than String. Now, the application code is simply:

      @GET     @Path("/test2")     public JaxbList test2(){         List list=new Vector();         list.add("a");         list.add("b");         return new JaxbList(list);     }  

Why doesn't this simple class exist in the JAXB package? Anyone see anything like it elsewhere?

Answer 2

@GET @Path("/test2") public Response test2(){    List<String> list=new Vector<String>();    list.add("a");    list.add("b");     final GenericEntity<List<String>> entity = new GenericEntity<List<String>>(list) { };    return Response.ok().entity(entity).build(); }