code: @Test public void mimeType() throws Exception {
    FileCopyUtils.copy("test",new FileWriter(this.temporaryFolder.newFile("test.xxcss")));
    AbstractEmbeddedServletContainerFactory factory=getFactory();
    factory.setDocumentRoot(this.temporaryFolder.getRoot());
    MimeMappings mimeMappings=new MimeMappings();
    mimeMappings.add("xxcss","text/css");
    factory.setMimeMappings(mimeMappings);
    this.container=factory.getEmbeddedServletContainer();
    this.container.start();
    ClientHttpResponse response=getClientResponse(getLocalUrl("/test.xxcss"));
    assertThat(response.getHeaders().getContentType().toString(),equalTo("text/css"));
    response.close();
  }
  