grails - 在grails中使用HTTP GET调用时，字段值呈现为空

Question

这是Person的 Realm 类:

 package com.sample
 class Person {
    String id
    String name
    Integer age
    Address address
static hasMany = [pets:Pet, alias: String, aliases : Alias]

static mapWith = "mongo"
 static constraints = {
      address nullable:true
      pets nullable :true
 }
}

这是Address的域类:

 package com.sample

 class Address {

   String address
   static mapWith = "mongo"
   static constraints = {
           address maxSize: 1000
   }
 }

这是PersonController中的ShowPerson方法:

 def showPerson(String name,String age){

            if(Person.findByAgeAndName(age,name) != null) {
                    render Person.findByAgeAndName(age,name) as JSON
            }
            else {

                def addobj = new Address(address: "kondapur")
                addobj.save(flush:true)

                def pet1 = new Pet(name : "Dog", breed : "A")
                pet1.save(flush:true)

                def alias1 = "ALIAS1"
                def alias2 = "ALIAS2"

                def list = ["A"]
                def aliases1 = new Alias(aliasname : [list])
                aliases1.save(flush:true)

                def person = new Person(name : name, age : age,  address : addobj, pets : [pet1], alias : [alias1, alias2], aliases : [aliases1])

                person.save()   

                render person as JSON
            }

        }

最初在DB中没有人员(这意味着Person.findByAgeAndName(age，name)== null)因此它创建了一个新对象并将其保存在数据库中。所以当我点击网址

 > http://localhost:8080/TestJson/showPerson/sample/23

现在的输出是:

现在，当我重新单击相同的URL时(暗示Person.findByAgeAndName(age，name)!= null)因此它是从数据库中获取的:

现在的输出是:

地址在数据库中另存为:

该人在数据库中另存为:

有人可以告诉我如何尝试从数据库中获取保存的对象(即本例中的kondapur而不是null)时，如何获取不为null的地址(红色圆圈)并获取相应的值。

Answer 1

默认情况下，Grails JSON marshaller不会添加嵌套类，您必须添加一行代码:

     def showPerson(String name,String age){

   JSON.use('deep')// <============================== Add this line

                if(Person.findByAgeAndName(age,name) != null) {
                        render Person.findByAgeAndName(age,name) as JSON
                }
            else {

                def addobj = new Address(address: "kondapur")
                addobj.save(flush:true)

                def pet1 = new Pet(name : "Dog", breed : "A")
                pet1.save(flush:true)

                def alias1 = "ALIAS1"
                def alias2 = "ALIAS2"

                def list = ["A"]
                def aliases1 = new Alias(aliasname : [list])
                aliases1.save(flush:true)

                def person = new Person(name : name, age : age,  address : addobj, pets : [pet1], alias : [alias1, alias2], aliases : [aliases1])

                person.save()   



                render person as JSON
            }

        }