Question

我是Play framework＆amp; ebean 并且想要一个通用的util函数来更新我的Model的实例所以我使用了以下代码：

private static void updateEntity(Class cls, Long id, ObjectNode data){
    Object instance = Ebean.find(cls,id);

    for (Field field :cls.getFields()){
        String fieldName = field.getName();
        if (!fieldName.equals("id")){
            field.setAccessible(true);
            try {
                field.set(instance, data.get(fieldName).toString());
            } catch (Exception e) {
                e.printStackTrace();
            }
        }
    }

    try {
      //not work  
      cls.getMethod("save").invoke(instance);
    } catch (IllegalAccessException e) {
        e.printStackTrace();
    } catch (InvocationTargetException e) {
        e.printStackTrace();
    } catch (NoSuchMethodException e) {
        e.printStackTrace();
    }
    //not work too
    //Ebean.save(instance);

}

我通过使用：

来调用它

    Long id = 1L;
    Class cls = MyEntity.class;
    ObjectNode data = Json.newObject();
    data.put("name","Hello world");
    data.put("id",1L);
    updateEntity(cls,id,data);

MyEntity是包含id和name的模型的nomarl实体类那么，我下一步该怎么办？

Answer 1

private static void updateEntity(Class cls, Long id, ObjectNode data){

User user = Ebean.find(cls,id);     // For example, consider Ebean returns 'User' object. You can mention your Model here.

try{
    user.getClass().getDeclaredField("id").set(user, data.get("id").toString());
}
catch(NoSuchFieldException exception){
    exception.printStackTrace();    // If no field is found in the name of `id`.
}   
catch(NullPointerException exception){
    exception.printStackTrace();    // If field name is null
}   
catch(Exception exception){
    exception.printStackTrace();
}   

user.save();
}

playframework 2.2.1 ebean如何使用java refection更新实体

1 个答案: