難度從服務器傳輸實體實例客戶

Question

我有一個Android客戶端和谷歌應用程序引擎的Servlet。
而我通過序列化將對象從客戶端傳輸到服務器。
序列化工作正常，所有的序列化對象在我的項目，
除了實體對象稱爲檔案，我在我的JPA DB現在的儲蓄。
現在，當我從客戶端轉移檔案實例的服務器，它工作正常
但是當我從服務器傳送到客戶端，我得到異常如下編寫。

我補充一點，我沒有在我的代碼代碼重複。
配置文件類位於服務器項目中，而客戶端項目包含服務器的路徑。

W/System.err(1104): java.io.InvalidClassException: javax.jdo.identity.LongIdentity; Incompatible class (SUID): javax.jdo.identity.LongIdentity: static final long serialVersionUID =2472141538875317527L; but expected javax.jdo.identity.LongIdentity: static final long serialVersionUID =2940818939440220368L; 

我Enity類是：

@Entity 
public class Profile implements Serializable 
{ 
    private static final long serialVersionUID = 1L; 

    @Id 
    @GeneratedValue(strategy = GenerationType.IDENTITY) 
    private Long id; 
    private int age; 
    private String email; 
    private boolean onlineStatus = false; 

    public Profile() {} 

    public Profile(int age,String email) 
    { 
     super(); 
     this.age = age; 
     this.email = email; 
    } 

    public int getAge() 
    { 
     return age; 
    } 
    public void setAge(int age) 
    { 
     this.age = age; 
    } 

    public String getEmail() 
    { 
     return email; 
    } 

    public void setEmail(String email) 
    { 
     this.email = email; 
    } 

    public boolean isOnlineStatus() 
    { 
      return onlineStatus; 
    } 

    public void setOnlineStatus(boolean onlineStatus) 
    { 
     this.onlineStatus = onlineStatus; 
    } 

完整的堆棧跟蹤：

04-21 21:04:56.577: W/System.err(1104): at java.io.ObjectInputStream.verifyAndInit(ObjectInputStream.java:2697) 
04-21 21:04:56.577: W/System.err(1104): at java.io.ObjectInputStream.readNewClassDesc(ObjectInputStream.java:1825) 
04-21 21:04:56.592: W/System.err(1104): at java.io.ObjectInputStream.readClassDesc(ObjectInputStream.java:811) 
04-21 21:04:56.592: W/System.err(1104): at java.io.ObjectInputStream.readNewObject(ObjectInputStream.java:2039) 
04-21 21:04:56.592: W/System.err(1104): at java.io.ObjectInputStream.readNonPrimitiveContent(ObjectInputStream.java:916) 
04-21 21:04:56.592: W/System.err(1104): at java.io.ObjectInputStream.readObject(ObjectInputStream.java:2262) 
04-21 21:04:56.592: W/System.err(1104): at java.io.ObjectInputStream.readObject(ObjectInputStream.java:2217) 
04-21 21:04:56.592: W/System.err(1104): at java.io.ObjectInputStream.readNewArray(ObjectInputStream.java:1678) 
04-21 21:04:56.592: W/System.err(1104): at java.io.ObjectInputStream.readNonPrimitiveContent(ObjectInputStream.java:914) 
04-21 21:04:56.592: W/System.err(1104): at java.io.ObjectInputStream.readObject(ObjectInputStream.java:2262) 
04-21 21:04:56.592: W/System.err(1104): at java.io.ObjectInputStream.readObject(ObjectInputStream.java:2217) 
04-21 21:04:56.597: W/System.err(1104): at java.io.ObjectInputStream.readFieldValues(ObjectInputStream.java:1291) 
04-21 21:04:56.597: W/System.err(1104): at java.io.ObjectInputStream.defaultReadObject(ObjectInputStream.java:518) 
04-21 21:04:56.597: W/System.err(1104): at java.io.ObjectInputStream.readObjectForClass(ObjectInputStream.java:1535) 
04-21 21:04:56.597: W/System.err(1104): at java.io.ObjectInputStream.readHierarchy(ObjectInputStream.java:1443) 
04-21 21:04:56.597: W/System.err(1104): at java.io.ObjectInputStream.readNewObject(ObjectInputStream.java:2112) 
04-21 21:04:56.597: W/System.err(1104): at java.io.ObjectInputStream.readNonPrimitiveContent(ObjectInputStream.java:916) 
04-21 21:04:56.597: W/System.err(1104): at java.io.ObjectInputStream.readObject(ObjectInputStream.java:2262) 
04-21 21:04:56.597: W/System.err(1104): at java.io.ObjectInputStream.readObject(ObjectInputStream.java:2217) 
04-21 21:04:56.597: W/System.err(1104): at java.io.ObjectInputStream.readNewArray(ObjectInputStream.java:1678) 
04-21 21:04:56.597: W/System.err(1104): at java.io.ObjectInputStream.readNonPrimitiveContent(ObjectInputStream.java:914) 
04-21 21:04:56.597: W/System.err(1104): at java.io.ObjectInputStream.readObject(ObjectInputStream.java:2262) 
04-21 21:04:56.607: W/System.err(1104): at java.io.ObjectInputStream.readObject(ObjectInputStream.java:2217) 
04-21 21:04:56.607: W/System.err(1104): at java.io.ObjectInputStream.readFieldValues(ObjectInputStream.java:1291) 
04-21 21:04:56.607: W/System.err(1104): at java.io.ObjectInputStream.defaultReadObject(ObjectInputStream.java:518) 
04-21 21:04:56.607: W/System.err(1104): at java.io.ObjectInputStream.readObjectForClass(ObjectInputStream.java:1535) 
04-21 21:04:56.607: W/System.err(1104): at java.io.ObjectInputStream.readHierarchy(ObjectInputStream.java:1443) 
04-21 21:04:56.607: W/System.err(1104): at java.io.ObjectInputStream.readNewObject(ObjectInputStream.java:2112) 
04-21 21:04:56.607: W/System.err(1104): at java.io.ObjectInputStream.readNonPrimitiveContent(ObjectInputStream.java:916) 
04-21 21:04:56.607: W/System.err(1104): at java.io.ObjectInputStream.readObject(ObjectInputStream.java:2262) 
04-21 21:04:56.607: W/System.err(1104): at java.io.ObjectInputStream.readObject(ObjectInputStream.java:2217) 
04-21 21:04:56.607: W/System.err(1104): at streetMeet.Client.CustomHttpClient.readObject(CustomHttpClient.java:274) 
04-21 21:04:56.607: W/System.err(1104): at streetMeet.Client.CustomHttpClient.executeHttpPost(CustomHttpClient.java:59) 
04-21 21:04:56.607: W/System.err(1104): at streetMeet.Client.StreetMeetActivity.connectToServer(StreetMeetActivity.java:154) 
04-21 21:04:56.607: W/System.err(1104): at streetMeet.Client.StreetMeetActivity.sendMessageToServer(StreetMeetActivity.java:141) 
04-21 21:04:56.607: W/System.err(1104): at map.StreetMapActivity$1.run(StreetMapActivity.java:116) 

Answer 1

請注意，Java對象序列化，不能保證不同的VM實現（GAE JVM和Android之間的合作Dalvik在這種情況下）。

您應該使用與平臺無關的格式進行序列化。大多數popoular是JSON。