Question

我尝试编译使用MongoDB和Morphia的GWT应用程序，但有例外：

*[ERROR] - Line 12: No source code is available for type com.google.code.morphia.Morphia; did you forget to inherit a required module?
[ERROR] - Line 13: No source code is available for type com.mongodb.DB; did you forget to inherit a required module?
[ERROR] - Line 15: No source code is available for type java.net.UnknownHostException; did you forget to inherit a required module?
[ERROR] - Line 15: No source code is available for type com.mongodb.MongoException; did you forget to inherit a required module?
[ERROR] - Line 17: No source code is available for type com.mongodb.Mongo; did you forget to inherit a required module?
[ERROR] - Line 27: No source code is available for type com.mongodb.DBCollection; did you forget to inherit a required module?*

将Morphia和MongoDB jar插入Java构建路径的Libraries部分（我正在使用Eclipse）。我还附上了MongoDB源代码。

当我没有使用Morphia时，一切正常。

这是我的班级代码：

package com.planner.shared;

import java.net.UnknownHostException;
import java.util.ArrayList;

import com.google.code.morphia.Morphia;
import com.mongodb.*;
import com.planner.shared.Project;
import com.planner.shared.ClassWrapper;

public class ProjectWrapper extends Base implements ClassWrapper {
 Morphia morphia;
 DB db;

 public ProjectWrapper() throws UnknownHostException, MongoException {
  super();
  Mongo m = new Mongo("127.0.0.1", 27017);
  db = m.getDB("planner");
  morphia = new Morphia();
  morphia.map(Project.class);
 }

 public ArrayList<Project> getProjects() {

  ArrayList<Project> projects = new ArrayList<Project>();
  //Get projects collection
  DBCollection projectsColl = db.getCollection("projects");
  //Get all projects from collection
  DBCursor cur = projectsColl.find();
  //Save all project to arrayList
  while(cur.hasNext()) {
   DBObject obj = cur.next();
   projects.add(morphia.fromDBObject(Project.class, obj));
  }
  return projects;
 }
}

有什么问题？

感谢。

Answer 1

Morphia GWT支持仍在建设中。

请参阅此问题：http://code.google.com/p/morphia/issues/detail?id=103

但似乎你还有其他问题。您无法使用共享代码连接到服务器，只能连接到服务器代码。您需要阅读并理解GWT项目中的代码。

morphia模块唯一支持的功能是能够将实体发送到GWT客户端代码。您实际上无法使用它或MongoDB驱动程序代码在客户端执行服务器操作; GWT永远不会允许这样做。

Answer 2

GWT需要MongoDb和Morphia类的源代码..但是，您不应该也不能将这些类用于应用程序的gwt层。另外你不能使用java.net包用于gwt层。您只能为gwt层使用java类的子集。

我建议你阅读GWT教程http://code.google.com/webtoolkit/doc/latest/tutorial/index.html。

使用MongoDB和Morphia编译GWT应用程序

2 个答案: