ObjectOutputStream -- Error.

[Sujatha Kumar]

Hi,

I am using objectoutputstream to read/write the contents of an array
to the file.

I dont get any problem if i read the file but i am encountering
the following error when i try to read from the file.

Reading from ObjectOuputStream
java.lang.ClassCastException: [LPatient;
at Ward.main(Ward.java:368)

Any help is appreciated.

Following are the two class files that i have been using.

public class Patient implements Serializable
{
private String name = null;

public String getName()
{
return name;
}

public void setName(String name)
{
this.name = name;
}
}


public class Ward
{
public static void main(String args[]) throws Exception
{

try
{
Patient[] patients = new Patient[1];
patients[0] = new Patient();

//Writing to File
patients[0].setName("Ravi");
File file = new File("myfile");
FileOutputStream fOS = new FileOutputStream (file);
ObjectOutputStream oOS = new ObjectOutputStream (fOS);
oOS.writeObject (patients);

//Reading From File
File myFile = new File("myfile");
FileInputStream fIS = new FileInputStream (myFile);
ObjectInputStream oIS = new ObjectInputStream(fIS);
patients[0] = (Patient) oIS.readObject();

}
catch(Exception e)
{
e.printStackTrace();
}
}
}

[Stefan Wagner]

oOS.writeObject (patients);
// ...
patients[0] = (Patient) oIS.readObject();

You write an array, and read it as single Object.
And code-tags wouldn't make your code less readable.
You may add them now.
[ August 22, 2004: Message edited by: Stefan Wagner ]

[Sujatha Kumar]

  
public class Patient implements Serializable
{
private String name = null;
 
public String getName()
{
return name;
}

public void setName(String name)
{
this.name = name;
} 
}
 

public class Ward
{
public static void main(String args[]) throws Exception
{

try
{
Patient[] patients = new Patient[1];
patients[0] = new Patient(); 

//Writing to File
patients[0].setName("Ravi"); 
File file = new File("myfile");
FileOutputStream fOS = new FileOutputStream (file);
ObjectOutputStream oOS = new ObjectOutputStream (fOS);
oOS.writeObject (patients); 

//Reading From File
File myFile = new File("myfile"); 
FileInputStream fIS = new FileInputStream (myFile);
ObjectInputStream oIS = new ObjectInputStream(fIS); 
patients[0] = (Patient) oIS.readObject();

}
catch(Exception e)
{
e.printStackTrace();
} 
}
}

I have added the code tags now, Could explain me why i am getting this
problem.

It would be great if you could give me the solution.

Regards

[Sujatha Kumar]

Hi Stephen,

Thanks for you reply, I got it right now by making the following
changes

  
File myFile = new File("myfile"); 
FileInputStream fIS = new FileInputStream (myFile);
ObjectInputStream oIS = new ObjectInputStream(fIS); 
patients = (Patient[]) oIS.readObject();

Regards