Extracting .jar file with command line

Question

I am trying to extract the files from a.jar file. How do I do that using command line?

I am running Windows 7

Answer 1

From the docs :

To extract the files from a jar file, use x , as in:

 C:\\Java> jar xf myFile.jar

To extract only certain files from a jar file, supply their filenames:

 C:\\Java> jar xf myFile.jar foo bar

The folder where jar is probably isn't C:\\Java for you, on my Windows partition it's:

C:\Program Files (x86)\Java\jdk[some_version_here]\bin

Unless the location of jar is in your path environment variable, you'll have to specify the full path/run the program from inside the folder.

EDIT: Here's another article, specifically focussed on extracting JARs: http://docs.oracle.com/javase/tutorial/deployment/jar/unpack.html

Answer 2

请注意，jar 文件是一个 Zip 文件，任何 Zip 工具（例如 7-Zip）都可以查看 jar 的内部。

Answer 3

在 Ubuntu 中：

unzip file.jar -d dir_name_where_extracting

Answer 4

You can use the following command: jar xf rt.jar

Where X stands for extraction and the f would be any options that indicate that the JAR file from which files are to be extracted is specified on the command line, rather than through stdin.

Answer 5

jar xf myFile.jar
change myFile to name of your file
this will save the contents in the current folder of .jar file
that should do :)

Answer 6

Java has a class specifically for zip files and one even more specifically for Jar Files.

java.util.jar.JarOutputStream
java.util.jar.JarInputStream

using those you could, on a command from the console, using a scanner set to system.in

Scanner console = new Scanner(System.in);
String input = console.nextLine();

then get all the components and write them as a file.

JarEntry JE = null;
while((JE = getNextJarEntry()) != null)
{
    //do stuff with JE
}

You can also use java.util.zip.ZipInputStream instead, as seeing a JAR file is in the same format as a ZIP file, ZipInputStream will be able to handle the Jar file, in fact JarInputStream actually extends ZipInputStream.

an alternative is also instead of getNextJarEntry, to use getNextEntry

Answer 7

Given a file named Me.Jar:

1. Go to cmd
2. Hit Enter

3. Use the Java jar command -- I am using jdk1.8.0_31 so I would type

   C:\\Program Files (x86)\\Java\\jdk1.8.0_31\\bin\\jar xf me.jar

That should extract the file to the folder bin. Look for the file .class in my case my Me.jar contains a Valentine.class

Type java Valentine and press Enter and your message file will be opened.

Answer 8

I had the same issue and the jar command did not work. I made a copy of the jar file and changed the extension to.zip. Then right click on the.zip file and select 'Extract All'. This extracted all the files.

Answer 9

要将 jar 解压缩到指定文件夹中，请通过命令提示符使用此命令

C:\Java> jar xf myFile.jar -C "C:\tempfolder"