Extracting the Contents of a JAR File
Trail: Deployment
Lesson: Packaging Programs in JAR Files
Section: Using JAR Files: The Basics

Extracting the Contents of a JAR File

The basic command to use for extracting the contents of a JAR file is:

jar xf jar-file [archived-file(s)]

Let's look at the options and arguments in this command:

As usual, the order in which the x and f options appear in the command doesn't matter, but there must not be a space between them.

When extracting files, the Jar tool makes copies of the desired files and writes them to the current directory, reproducing the directory structure that the files have in the archive. The original JAR file remains unchanged.

Caution: When it extracts files, the Jar tool will overwrite any existing files having the same pathname as the extracted files.

An Example

Let's extract some files from the TicTacToe JAR file we've been using in previous sections. Recall that the contents of TicTacToe.jar are:


Suppose you want to extract the TicTacToe class file and the cross.gif image file. To do so, you can use this command:

jar xf TicTacToe.jar TicTacToe.class images/cross.gif

This command does two things:

The original TicTacToe JAR file remains unchanged.

As many files as desired can be extracted from the JAR file in the same way. When the command doesn't specify which files to extract, the Jar tool extracts all files in the archive. For example, you can extract all the files in the TicTacToe archive by using this command:

jar xf TicTacToe.jar

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