What is the "jar" command to update an existing JAR file with new or additional files?

To update an existing JAR file with new or additional files, you can use the "jar -uvf jarname files" command.

For example, the following session updates an existing JAR file with some additional classes:

\fyicenter>"%java_home%\bin\jar" -xvf jms.jar

\fyicenter>"%java_home%\bin\jar" -cvf myNew.jar .\javax

\fyicenter>"%java_home%\bin\javac" Hello.java

\fyicenter>"%java_home%\bin\jar" -uvf myNew.jar Hello.class
adding: Hello.class(in = 416) (out= 286)(deflated 31%)

\fyicenter>"%java_home%\bin\jar" -tf myNew.jar
META-INF/
META-INF/MANIFEST.MF
javax/
javax/jms/
javax/jms/BytesMessage.class
javax/jms/Connection.class
javax/jms/ConnectionConsumer.class
...
javax/jms/XATopicConnectionFactory.class
javax/jms/XATopicSession.class
Hello.class

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