如何将一个List>类型的集合数据转换成json格式输出

------解决方案--------------------------------------------------------
去网上下一个json-lib-2.4-jdk15.jar和ezmorph-1.0.6.jar，就可以调用
List<Map> list = new ArrayList<Map>();
String json = JSONArray.fromObject(list).toString(); 
------解决方案--------------------------------------------------------
Java code

List<Map<String,String>>

StringBuilder sb = new StringBuilder();
        sb.append("{");
   for(Map<String,String> map:list){
        for (String key : map.keySet()) {
            sb.append("\"").append(key).append("\":\"").append(map.get(key))
                    .append("\"").append(",");
        }
}
        sb.deleteCharAt(sb.lastIndexOf(","));
        sb.append("}");