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Getting Object back from an ObjectOutputStream

I have created an ObjectOutputStream
ObjectOutputStream stream = new ObjectOutputStream(new ByteArrayOutputStream());
stream.writeObject(myObject);
but how do I now convert this back into an Object, or even a ByteArray?
I've tried getting an ObjectInputStream like this
ByteArrayOutputStream outputStream = (ByteArrayOutputStream) myProcess.getOutputStream();
final ObjectInputStream objectInputStream = new ObjectInputStream(
new ByteArrayInputStream(outputStream.toByteArray()));
however I get a compile error saying it can't cast the ObjectOutputStream to a ByteArrayOutputStream; yet there seem to be no methods on the ObjectOutputStream to get the data back?

Here how you do it
ByteArrayOutputStream baos = new ByteArrayOutputStream();
ObjectOutputStream stream = new ObjectOutputStream(baos);
stream.writeObject(myObject);
ByteArrayInputStream bais = new ByteArrayInputStream(baos.toByteArray());
ObjectInputStream inputStream = new ObjectInputStream(bais);
Object o = inputStream.readObject();

reading bytearray upto specified location

Let me allow to describe my problem:
I have created socket server in python and client in java, from java I am sending multiple objects to server by using :
ByteArrayOutputStream bos = new ByteArrayOutputStream();
ByteArrayOutputStream append = new ByteArrayOutputStream();
ObjectOutput out = null;
byte finalarr[]=null;
try {
out = new ObjectOutputStream(bos);
out.writeObject(object);
out.flush();
byte[] objByte = bos.toByteArray();
bos.close();
out.close();
append.write(objByte.length);
append.write(objByte);
bos = new ByteArrayOutputStream();
out = new ObjectOutputStream(bos);
out.writeObject(value);
out.flush();
append.write(bos.toByteArray());
finalarr = append.toByteArray( );
os = sChannel.socket().getOutputStream();
oos = new ObjectOutputStream(os);
oos.write(finalarr);
} finally {
try {
bos.close();
} catch (IOException ex) {
}
}
Now, finalarr contains byte length of object then actual byte[] of object and then byte[] of value. Now in python after receiving this First I want to read length of byte which is written in first position of finalarr then whatever length I get I want to read received array upto that length so that I will get object separately then the remaining part separately.
In python I have done upto this:
total_data=b''
while True:
data = self.clientsocket.recv(1024)
if not data: break
total_data += data
In total_data I am getting entire bytearray, but I don't know how I can read it so that I can get two objects separately as explained.

java.io.StreamCorruptedException: invalid stream header when sending an image

In my server i'm trying to split an image and send it to the clients (here are called resources). The problem is that I get StreamCorruptedException when I read the object.
Server side:
Socket resSocket = resourceQueue.get(k).getSocket();
DataOutputStream dos = new DataOutputStream(resSocket.getOutputStream());
FileInputStream fis = new FileInputStream(chunksList.get(i));
byte[] data = new byte[fis.available()];
fis.read(data);
ObjectOutputStream oos = new ObjectOutputStream(resSocket.getOutputStream());
oos.writeObject(data);
oos.close();
Client side
ObjectInputStream ois = new ObjectInputStream(sock.getInputStream()); // Here i get the error
byte[] buffer = (byte[]) ois.readObject();
String path = "c:/JGCF/temp."+"jpg";
System.out.println(path);
FileOutputStream fos = new FileOutputStream(path);
fos.write(buffer);

Deserializable exception : local class is not compatible cause of serialVersionID

Here is my code:
MyOwnObject deserializedObject = null;
try{
ByteArrayInputStream bis = new ByteArrayInputStream(serializedObject.getBytes());
ObjectInputStream ois= new ObjectInputStream(bis);
deserializedObject = (MyOwnObject)ois.readObject();
ois.close();
}catch(Exception e){
e.printStackTrace();
}
someMapper.insert(deserializedObject);
PS: serializedObject is a string which i get from serialization process before, and it's working well i think.
The code throws an exception:
local class incompatible: stream classdesc serialVersionUID = 1360826667802527544, local class serialVersionUID = 1360826667806852920
And in the stacktrace there's something about the type Integer of some attribute in my object.
UPDATE:
serializeObject is a string,from this code:
try {
ByteArrayOutputStream bo = new ByteArrayOutputStream();
ObjectOutputStream so = new ObjectOutputStream(bo);
so.writeObject(myObject);
so.flush();
serializedObject = bo.toString();
}catch (Exception e) {
System.out.println(e);
}
ANSWER:
//Serialization from object to string
String serializedObject="";
try{
ByteArrayOutputStream baos = new ByteArrayOutputStream();
ObjectOutputStream oos = new ObjectOutputStream(baos);
oos.writeObject(object);
oos.flush();
serializedObject = new String(Base64.encode(baos.toByteArray()));
oos.close();
}catch(Exception e){
e.printStackTrace();
}
//Deserialization from string to object
MyOwnObject deserializedObject = null;
try{
byte[] bytes = Base64.decode(serializedObject.getBytes());
ByteArrayInputStream bais = new ByteArrayInputStream(bytes);
ObjectInputStream ois = new ObjectInputStream(bais);
deserializedObject = (MyOwnObject)ois.readObject();
ois.close();
}catch(Exception e){
e.printStackTrace();
}
From here,i can use deserializedObject as an object,and it worked well!

The problem is in how you create your serializedObject.
You use a ByteArrayOutputStream. You shouldn't call toString() on it. Instead call its toByteArray() method to get the underlying data as a byte array, and you can use that to create your ByteArrayInputStream and it will work.
Example:
// Serialization
ByteArrayOutputStream bo = new ByteArrayOutputStream();
ObjectOutputStream so = new ObjectOutputStream(bo);
so.writeObject(myObject);
so.flush();
byte[] serializedObject = bo.toByteArray();
// Deserialization
MyOwnObject deserializedObject = null;
try {
ByteArrayInputStream bis = new ByteArrayInputStream(serializedObject);
ObjectInputStream ois = new ObjectInputStream(bis);
deserializedObject = (MyOwnObject)ois.readObject();
ois.close();
} catch (Exception e){
e.printStackTrace();
}
A serialized object is a sequence of bytes (a byte array) and not a sequence of characters. You cannot create a String from the bytes of a serialized object, because it may not contain valid unicode codepoints for example.
If you really need to represent the serialized object as a String, try representing the byte array in hex string or use base64 encoding.

besides base64, you can use hex string also!i always use it when i encounter a similar problems!

byte array in java returning null after conversion from objects

I need to send my phone contacts in android as bytes. So i have crated a bean class implementing serializable , but after converting the arraylist of bean class to byte array, byte array is always showing null. Here is my sample code.
ByteArrayOutputStream baos = new ByteArrayOutputStream();
ObjectOutputStream oos = new ObjectOutputStream(baos);
oos.writeObject(presentContacts);
byte[] buf = baos.toByteArray();
Here presentContacts is the ArrayList of bean class. Byte array, buf is always returning null but presentContacts is not null.

You should probably close or at least flush the ObjectOutputStream.
Something like this
ByteArrayOutputStream baos = new ByteArrayOutputStream();
ObjectOutputStream oos = new ObjectOutputStream(baos);
oos.writeObject(presentContacts);
oos.flush();
byte[] buf = baos.toByteArray();