`OutputDecorator` not called with `XmlMapper`

[ndionisi]

OutputDecorator seems to be ignored on XmlMapper.
With a (JSON) ObjectMapper, the following test passes:

    @Test
    public void json_objectMapper_should_use_decorator() throws Exception {
        ObjectMapper objectMapper = new ObjectMapper();
        objectMapper.getFactory().setOutputDecorator(new OutputDecorator() {
            @Override
            public OutputStream decorate(IOContext ctxt, OutputStream out) throws IOException {
                out.write("DECORATOR".getBytes(StandardCharsets.UTF_8));
                return out;
            }

            @Override
            public Writer decorate(IOContext ctxt, Writer w) throws IOException {
                w.write("DECORATOR");
                return w;
            }
        });
        assertThat(objectMapper.writeValueAsString("value")).isEqualTo("DECORATOR\"value\"");
    }

But with an XmlMapper, the following test fails:

    @Test
    public void xml_objectMapper_should_use_decorator() throws Exception {
        ObjectMapper objectMapper = new XmlMapper();
        objectMapper.getFactory().setOutputDecorator(new OutputDecorator() {
            @Override
            public OutputStream decorate(IOContext ctxt, OutputStream out) throws IOException {
                out.write("DECORATOR".getBytes(StandardCharsets.UTF_8));
                return out;
            }

            @Override
            public Writer decorate(IOContext ctxt, Writer w) throws IOException {
                w.write("DECORATOR");
                return w;
            }
        });
        assertThat(objectMapper.writeValueAsString("value")).isEqualTo("DECORATOR<String>value</String>");
    }

with the following error:

org.junit.ComparisonFailure: 
Expected :"DECORATOR<String>value</String>"
Actual   :"<String>value</String>"

According to the source code, it seems that the XmlFactory never calls its _decorate() method.

[cowtowncoder]

That is quite possible: I fixed this, I think, for 3.0 (master) and possibly for 2.10.

Which version is this with?

[ndionisi]

Sorry, should have mentionned the version. Got the issue in 2.9.8