Name

serialver — Class Version Number Generator

Synopsis

serialver [ -classpath path ] classnames...
serialver [ -classpath path ] -show

Description

serialver displays the version number of a class or classes. This version number is used for the purposes of serialization: the version number must change each time the serialization format of the class changes.

If the specified class declares a long serialVersionUID constant, the value of that field is displayed. Otherwise, a unique version number is computed by applying the Secure Hash Algorithm (SHA) to the API defined by the class. This program is primarily useful for computing an initial unique version number for a class, which is then declared as a constant in the class. The output of serialver is a line of legal Java code, suitable for pasting into a class definition.

Options

-classpath path

Specifies the search path for classes.

-show

When the -show option is specified, serialver displays a simple graphical interface that allows the user to type in a single class name at a time and obtain its serialization UID. When using -show, no class names can be specified on the command line.

Environment

CLASSPATH

serialver is written in Java, so it is sensitive to the CLASSPATH environment variable in the same way the java interpreter is. The specified classes are looked up relative to this classpath.

See also

java.io.ObjectStreamClass

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