serialver - serialVersionUID Generator

Java Tools Tutorials - Herong's Tutorial Examples

∟serialver - serialVersionUID Generator

This chapter provides provides a tutorial example on how to use 'serialver' command to generate a unique 'serialVersionUID' value for any given serializable Java class.

What Is "serialver"? - "serialver" is a command line tool that generates a unique value for "serialVersionUID" for a given Java class code.

If you have %java_home%\bin directory included in "path" the environment variable, you can run "serialver" to get the usage information:

herong> serialver

use: serialver [-classpath classpath] [classname...]

1. Try "serialver" on the Hello.java class. It gives an error: "Class Hello is not Serializable".

herong> type Hello.java
class Hello {
   public static void main(String[] a) {
      System.out.println("Hello world!");
   }
}

herong> javac Hello.java

herong> serialver Hello
Class Hello is not Serializable.

2. Try "serialver" on a serializable class, HelloSerializable.java. I get a serialVersionUID value.

herong> type HelloSerializable.java
import java.io.Serializable;
class HelloSerializable implements Serializable {
   public static void main(String[] a) {
      System.out.println("Hello world! - Serializable");
   }
}

herong> javac HelloSerializable.java

herong> serialver HelloSerializable
HelloSerializable:
   private static final long serialVersionUID = 2133400551086625355L;

3. Put the serialVersionUID value into the class source code to make it complete.

herong> type HelloSerializable.java

import java.io.Serializable;
class HelloSerializable implements Serializable {
   private static final long serialVersionUID = 2133400551086625355L;
   public static void main(String[] a) {
      System.out.println("Hello world! - Serializable");
   }
}