如何返回Objectify上的自定义对象列表 [英] How to return a list of custom objects on Objectify
问题描述
我正在研究一个使用Google App Engine作为后端的Android项目,如下所述:使用Android&在Android Studio上的Google App Engine 。
我在后端有一些模型类,像User和Item,我试图返回一个Items用户拥有。
public List< Ref< Item>> getItems(){
返回项目;
}
当我尝试与Gradle文件同步项目
,我得到这个错误:
错误:任务':backend:appengineEndpointsGetClientLibs'的执行失败。
运行endpoints命令时发生错误get-client-lib:参数化类型com.googlecode.objectify.Ref≤backend.model.Item>不支持。
我在这里查了一些其他的问题,并且通过添加 @ApiResourceProperty(ignored = AnnotationBoolean.TRUE)
注解来构建项目而没有错误我的getter方法。但添加完这一行后,我无法在Android应用程序端看到此方法。
任何想法如何使获得Android端项目列表成为可能? p>
我通过保存/检索包含序列化集合的对象来完成此操作。 Class Lesson实现了Serializable。
Language.java
import java.io.Serializable;
import java.util.List;
import com.googlecode.objectify.annotation.Entity;
import com.googlecode.objectify.annotation.Id;
import com.googlecode.objectify.annotation.Serialize;
@Entity
公共类语言{
@Id
私有字符串键;
私有字符串标题;
@Serialize
私人列表<课程>教训; //这里收集
// getters / setters ommited
}
LanguageService.java
import static com.googlecode.objectify.ObjectifyService.ofy;
导入com.google.api.server.spi.config.Api;
import com.google.api.server.spi.config.ApiMethod;
import com.google.api.server.spi.config.Named;
import com.googlecode.objectify.Key;
import com.googlecode.objectify.ObjectifyService;
import com.minspok.entity.Language;
$ b @Api(name =langapi,version =v1,description =langapi)
public class LanguageService {
static {
ObjectifyService.register(Language.class);
$ b @ApiMethod(name =get)
public语言getLanguage(@Named(key)字符串键){
语言语言= ofy()。load()。key(Key.create(Language.class,
key))。now();
返回语言;
$ b @ApiMethod(name =create)
public void createLanguage(语言语言){
ofy()。save()。实体(语言);
有用阅读: https://github.com/objectify/objectify/wiki/Entities
I'm working on an Android project which uses Google App Engine for backend as described here: Using Android & Google App Engine on Android Studio.
I have some model classes on the backend side like User and Item, and I'm trying to return a list of Items user has.
public List<Ref<Item>> getItems() {
return items;
}
When I try to Sync Project with Gradle Files
, I get this error:
Error:Execution failed for task ':backend:appengineEndpointsGetClientLibs'. There was an error running endpoints command get-client-lib: Parameterized type com.googlecode.objectify.Ref≤backend.model.Item> not supported.
I checked some other questions here and was able to build the project without errors by adding @ApiResourceProperty(ignored = AnnotationBoolean.TRUE)
annotation to my getter method. But after adding this line, I cannot see this method on Android app side.
Any idea how to make it possible to get a list of Items on Android side?
I did it by saving/retrieving object that contains serialized collection. Class Lesson implements Serializable.
Language.java
import java.io.Serializable;
import java.util.List;
import com.googlecode.objectify.annotation.Entity;
import com.googlecode.objectify.annotation.Id;
import com.googlecode.objectify.annotation.Serialize;
@Entity
public class Language {
@Id
private String key;
private String title;
@Serialize
private List<Lesson> lessons; //here collection
//getters/setters ommited
}
LanguageService.java
import static com.googlecode.objectify.ObjectifyService.ofy;
import com.google.api.server.spi.config.Api;
import com.google.api.server.spi.config.ApiMethod;
import com.google.api.server.spi.config.Named;
import com.googlecode.objectify.Key;
import com.googlecode.objectify.ObjectifyService;
import com.minspok.entity.Language;
@Api(name = "langapi", version = "v1", description = "langapi")
public class LanguageService {
static{
ObjectifyService.register( Language.class );
}
@ApiMethod(name = "get")
public Language getLanguage(@Named("key") String key){
Language language = ofy().load().key(Key.create(Language.class,
key)).now();
return language;
}
@ApiMethod(name = "create")
public void createLanguage(Language language){
ofy().save().entity(language);
}
}
Helpful reading: https://github.com/objectify/objectify/wiki/Entities
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