Serializing objects to 8i
Hi,
This may have been asked before, but does anyone know if it's possible to serialize/de-serialize a Java object directly into an 8i table? If so, are there any code examples I could have a look at?
Thanks in anticipation,
Rich
Hi,
You could do that for j2se applications by serializing and deserializing objects (you could use data input and output streams to send byte corresponding of your object, and serialize and deserialize over http or socket connection). Lacking serializing support in clcd makes it difficult to serialize and deserialize. but there is an implementation of serialization [http://java.sun.com/developer/J2METechTips/2002/tt0226.html#tip2] and some revisions about that code on [http://j2me.synclastic.com/2006/07/25/revisiting-j2me-object-serialization/].
Best,
Canawar
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FileUpload problem: InputStream does not contain a serialized object
Hi All,
I'm using the FileUpload component in a JSPDynPage and the htmlb component seems to work fine but I cannot read the file (InputStream). I get the following error(IOException): "InputStream does not contain a serialized object".
Please let me know what is wrong with my code. This is a part of the code I used:
public FileInputStream sourceFileInput;
public ObjectInputStream input;
FileUpload fu;
fu = (FileUpload) this.getComponentByName("myFileUpload");
IFileParam fileParam = ((FileUpload) getComponentByName("myFileUpload")).getFile();
File f = fileParam.getFile();
file = fu.getFile().getFile();
absolutepath = fu.getFile().getFile().getAbsolutePath();
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input = new ObjectInputStream(sourceFileInput);
The last line of code seems to generate te error.Hi,
I have found the answers, thank you both.
(I included the examle code. Perhaps of some use to someone.)
FileUpload fu;
fu = null;
fu = (FileUpload) this.getComponentByName("myFileUpload");
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if (fileParam != null) {
// get info about this file and create a FileInputStream
File f = fileParam.getFile();
if (f != null) {
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catch (FileNotFoundException ex) {
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isr = new InputStreamReader(fis);
br = new BufferedReader(isr);
String textLine = "";
do {
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// Jco append table & put data into the record
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I_FILE.setValue(textLine, "REC");
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StreamCorruptedException: does not contain a serialized object?
Can someone tell me why am I getting this exception:
C:\javapr>java FetchObject
Couldn't retrieve binary data: java.io.StreamCorruptedException: InputStream
does not contain a serialized object
java.io.StreamCorruptedException: InputStream does
not contain a serialized object
at java.io.ObjectInputStream.readStreamHeader
(ObjectInputStream.java:849)
at java.io.ObjectInputStream.<init>
(ObjectInputStream.java:168)
at FetchObject.main(FetchObject.java:23)
import java.sql.*;
import java.util.*;
import java.io.*;
class FetchObject implements Serializable {
public static void main (String[] args) {
try {
String driver = "oracle.jdbc.driver.OracleDriver";
Class.forName(driver);
String url = "jdbc:oracle:thin:@mymachine:1521:homedeva";
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byte[] returndata = null;
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ResultSet rs = stmt.executeQuery(sql);
if ( rs.next() )
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byte[] bindata = new byte[4096];
int bytesread = 0;
if ( !rs.wasNull() )
if ( (bytesread = bis.read(bindata,0,bindata.length)) != -1 )
baos.write(bindata,0,bytesread);
returndata = baos.toByteArray();
baos.flush();
bis.close();
catch ( Exception ex )
System.err.println("Problem retrieving binary data: " + ex);
rs.close();
stmt.close();
catch ( Exception ex )
System.err.println("Couldn't retrieve binary data: " + ex);
return returndata;
import java.io.*;
class Employee implements Serializable
private String lastName;
private String firstName;
public Employee(String lastName, String firstName)
this.lastName = lastName;
this.firstName = firstName;
}To clarify I have stored an Employee Object as a Blob in the Oracle database and am attempting to retreive the
Employee Object from this Blob.
Thanks -
Java.io.StreamCorruptedException: InputStream does not contain a serialized object
I have an applet which calls a JSP to write data object to the db and then the
JSP sends back the updated data object. The writing part is ok but the response
is giving the following error. The data object is in a separate class which implements
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at java/io/ObjectInputStream.<init>
What am I doing wrong?. Please respond soon. The applet is run on IIS and the
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I have an applet which calls a JSP to write data object to the db and then the
JSP sends back the updated data object. The writing part is ok but the response
is giving the following error. The data object is in a separate class which implements
Serialized.
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URL server = null;
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result = response.readObject();
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at java/io/ObjectInputStream.<init>
What am I doing wrong?. Please respond soon. The applet is run on IIS and the
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Hi there,
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null -
Reducing Size of Serialized Object
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Hi!
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Hello everybody,
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there any way there I can predict excatly the size
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Dave. -
Serializing objects with the NIO API
I try to use the new IO API to implement a non-blocking multi-threaded server that communicates with client applications by exchanging serialized objects. I started from the code in the JavaWorld article at http://www.javaworld.com/javaworld/jw-09-2001/jw-0907-merlin.html .
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Saving and loading serialized objects (StreamCorruptedException)
Hello,
I am relatively new to Serialization (coming to that, a bit new to Java too) and I am having a problem with the following:
I am saving a number of serialized objects (all of the same class) in a file using the following way (the method is called multiple times to save a list of TeamMember objects):
Note: TeamMember is a custom class.
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outputStream.flush();
outputStream.close();
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public TeamMember getTeamMember(String id) {
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boolean found = false;
inputStream = new ObjectInputStream( new FileInputStream( "team.dat" ) );
while ( !found ) {
currentMember = (TeamMember)inputStream.readObject();
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found = true;
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closeInputFile();
return currentMember;
} // end try
catch ( EOFException e ) { // end of file reached
closeInputFile();
return null;
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closeInputFile();
System.err.println( e.getMessage() );
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While tracing the program, I've seen that it always gives me that error when reading past the first object saved in the file.
Am I saving the objects in a wrong way, or reading them is done incorrectly?
Any help is much appreciated.
I hope I was clear enough, and that I posted in the correct forum.
Thanks in advance.
Andrew.If that is so, might you hint me for a work around?
I want to append objects in a single file, then be able to find and read an object from the file.
Thanks again.
Andrew -
What is the Error (de-)serializing object
Hi all
I have 2 EJB's one Stateful(Bean1) and Statless (Bean2). Bean1 lookup on Bean2 and get the remote object of Bean2 (Bean2Remote) and but it in a class that implements java.io.Serializable but when we return that class that holds the Bean2 remote the server throws
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Can any one help in that thanks in advanceHaving the same problem as many others here. I keep getting error message "0xFFFE7958". I have tried about 25 times over several days with 2 different computers using both tiger and panther and I still cant get the file to download. The episode that is giving me trouble is "Orientation" in second season of Lost. I have noticed that other peeps have had trouble with the same file. I don't think it's me!! I won't be downloading any itunes content until this gets fixed.
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Bizarre ClassCastException when sending serialized objects
I have two programs communicating with each other over a network using TCP and serialized objects. One of the programs uses an ObjectOutputStream to send the message, and the other uses an ObjectInputStream to receive it. The receiver has a thread that simply loops, receiving and processing messages one at a time.
Under normal circumstances, this works fine. However, sometimes the sender program has to send more than one message, one right after the other. I guess my assumption was that on the receiving end, they would somehow just "queue up" in the ObjectInputStream and the receiver would be able to read them one at a time. But instead, I get this bizarre ClassCastException whose message talks about members and objects from both messages that were sent. It is as though somehow the two objects received are being mangled together and interpreted somehow as one object. This is strange to me, since I am pretty sure TCP is supposed to guarantee in-order delivery of packets.
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If you need more details, it works like this. I have two classes that look like this:
class Class1 extends SerializableSuperclass
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class Class2 extends SerializableSuperclass
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How do I fix or work around this?
ThanksThese classes do not have those methods. They are simply message classes designed to hold data. Do you need to see the methods that call ObjectOutputStream's writeObject() and ObjectInputStream's readObject() methods?
The serializable superclass is there because it has other stuff including a field identifying the sender. It's basically a base message class.
Also, the member classes are serializable (serializability isn't the issue anyway; "class cast" is the issue). -
Opening files with serialized objects even if class definition has changed.
Dear all,
We are deploying an application wich saves serialized objects. But when changing something in the code and especially in the serialized classes we are not able to open files which have been saved with the old 'outfit' of the class.
I think, that this is probably a common problem and therefore I am interested whether there exists also a common or practical solution.
What is the direction I have to look in? XML, Serializable or is it something else?
Thanks for a short answer,
AxelIf you add, remove or change a classes variables, then it will be serialized differently.
Any fields which you do not need to be serialized, may be marked as transient, so you can add and remove them at will.
In the longer term, you can override the readObject() / writeObject() methods and explicitely load/save what fields you want. This will also allow you to set intelligent defaults, if for example, you added a new field, but your old serialised classes do not have this field. You can also precede all serialised data with version numbers... might help a bit.
So code ( psuedocode ) might look like this...
private void readObject(java.io.ObjectInputStream in)
throws IOException, ClassNotFoundException;
int ver = in.readInt();
classfield1 = in.readLong();
if ( ver >= 2 )
classfield2 = in.readLong();
if ( ver >= 3 )
classfield3 = in.readLong();
}regards,
Owen
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