code: @Test @SuppressWarnings("unchecked") public void testLinkedMap() throws Exception {
    LinkedHashMap<String,String> map=new LinkedHashMap<String,String>();
    map.put("aaa","bbb");
    StringWriter writer=new StringWriter();
    JSON.json(map,writer);
    String json=writer.getBuffer().toString();
    Assert.assertEquals("{\"aaa\":\"bbb\"}",json);
    StringReader reader=new StringReader(json);
    LinkedHashMap<String,String> result=JSON.parse(reader,LinkedHashMap.class);
    Assert.assertEquals("bbb",result.get("aaa"));
  }
  