Question

我一直在试图弄清楚这个序列化哈希表，并在一段时间内保存/加载到磁盘业务。当我调用方法'saveDataToDisk'时，我将它传递给我创建的哈希表对象。

它保存并且似乎工作正常，然后当我尝试加载它时，它会在读取时跳转到catch块

ObjectInputStream ois = new ObjectInputStream(new FileInputStream("/dev/null"));。

错误输出如下，任何帮助将非常感激。先谢谢费拉斯。

public boolean saveDataToDisk(Object hashObject)
{
    FileOutputStream fos;
    try
    {
        fos = new FileOutputStream("/dev/null");
        ObjectOutputStream oos;
        oos = new ObjectOutputStream(fos);
        oos.writeObject(hashObject);
        oos.close();
    }
    catch (FileNotFoundException e)
    {
        // TODO Auto-generated catch block
        e.printStackTrace();
    }
    catch (IOException e)
    {
        // TODO Auto-generated catch block
        e.printStackTrace();
    }
    return true;
}

public static Hashtable<String, Object> loadDataFromDisk()
{
    Hashtable<String, Object> newHash = null;
    FileInputStream fis;
    try
    {
        ObjectInputStream ois = new ObjectInputStream(new FileInputStream("/dev/null"));
        newHash = (Hashtable<String, Object>) ois.readObject();
        System.out.println("newHash");
    }
    catch (ClassNotFoundException cnfe)
    {
        Log.e("deserializeObject", "class not found error", cnfe);

        return null;
    }
    catch (IOException ioe)
    {
        Log.e("deserializeObject", "io error", ioe);

        return null;
    }

    if (newHash == null)
        newHash = new Hashtable<String, Object>();
    return newHash;
}

这是错误：

11-15 23:29:55.282: ERROR/deserializeObject(895): io error
11-15 23:29:55.282: ERROR/deserializeObject(895): java.io.EOFException
11-15 23:29:55.282: ERROR/deserializeObject(895):     at java.io.DataInputStream.readShort(DataInputStream.java:376)
11-15 23:29:55.282: ERROR/deserializeObject(895):     at java.io.ObjectInputStream.readStreamHeader(ObjectInputStream.java:2365)
11-15 23:29:55.282: ERROR/deserializeObject(895):     at java.io.ObjectInputStream.<init>(ObjectInputStream.java:433)
11-15 23:29:55.282: ERROR/deserializeObject(895):     at B.Duy.Le.PersistentHandler.loadDataFromDisk(PersistentHandler.java:125)
11-15 23:29:55.282: ERROR/deserializeObject(895):     at B.Duy.Le.PersistentTest$1.onClick(PersistentTest.java:85)
11-15 23:29:55.282: ERROR/deserializeObject(895):     at android.view.View.performClick(View.java:2485)
11-15 23:29:55.282: ERROR/deserializeObject(895):     at android.view.View$PerformClick.run(View.java:9080)
11-15 23:29:55.282: ERROR/deserializeObject(895):     at android.os.Handler.handleCallback(Handler.java:587)
11-15 23:29:55.282: ERROR/deserializeObject(895):     at android.os.Handler.dispatchMessage(Handler.java:92)
11-15 23:29:55.282: ERROR/deserializeObject(895):     at android.os.Looper.loop(Looper.java:123)
11-15 23:29:55.282: ERROR/deserializeObject(895):     at android.app.ActivityThread.main(ActivityThread.java:3683)
11-15 23:29:55.282: ERROR/deserializeObject(895):     at java.lang.reflect.Method.invokeNative(Native Method)
11-15 23:29:55.282: ERROR/deserializeObject(895):     at java.lang.reflect.Method.invoke(Method.java:507)
11-15 23:29:55.282: ERROR/deserializeObject(895):     at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:839)
11-15 23:29:55.282: ERROR/deserializeObject(895):     at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:597)
11-15 23:29:55.282: ERROR/deserializeObject(895):     at dalvik.system.NativeStart.main(Native Method)

Answer 1

我使用了类似的代码....可能这可以帮到你。并且它正常工作

保存：其中requestDataMap是HashMap

File directoryName = new File(Environment.getExternalStorageDirectory(),"/folder1/subfolder");
    directoryName.mkdirs();
    File outputFile = new File(directoryName, filename);
    FileOutputStream fos;

    try {

        fos = new FileOutputStream(outputFile);

        ObjectOutputStream out = new ObjectOutputStream(fos);

        out.writeObject(requestDataMap);
        fos.flush();
        fos.close();

加载

HashMap<String, Object> requestDataMap=new HashMap<String, Object>();
    File directoryName = new File(Environment.getExternalStorageDirectory(),"/folder1/subfolder1");
    directoryName.mkdirs();
    File outputFile = new File(directoryName,fileName);
    FileInputStream fis;
    try {
        fis = new FileInputStream(outputFile);
            ObjectInputStream ois = new ObjectInputStream(fis);
            requestDataMap = (HashMap<String, Object>) ois.readObject();
            ois.close();
    }

从磁盘加载我的android序列化有什么问题？

1 个答案: