Code Sample: Shows how to read a serialized object and print its information
An Introduction to Socket Programming
(Continued from previous question...)
Code Sample: Shows how to read a serialized object and print its information
Code Sample: ReadDate.java
import java.io.*;
import java.util.Date;
public class ReadDate {
public static void main
(String argv[]) throws Exception
{
FileInputStream fis =
new FileInputStream("date.out");
ObjectInputStream ois =
new ObjectInputStream(fis);
Date date = (Date) ois.readObject();
System.out.println("The date is: "+date);
ois.close();
fis.close();
}
}
In the example above we have worked with an instance of
the Date class, which is an existing serialized
Java class. The question that may come to mind is: are all
existing Java class serialized? The answer is: No.
Either because they don't need to be, or it doesn't make sense
to serialize some classes. To find out if a class is serializable,
use the tool serialver that comes with the JDK. You can
either use it from the command line as follows:
c:\> serialver java.util.Date
java.util.Date: static final long serialVersionUID = 7523967970034938905L;
(In this example, we are testing if the Date
class is serializable. The output here means that the Date
class is serializable and it print its version unique identifier.)
Or, alternatively, you can use the GUI-based
serialver tool using the command:
c:\> serialver -show
This command pops up a window, where
you can write the name of the class (including its path)
that you want to check.
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