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How to run an extracted jar?

If I extract a Jar file into a directory, what's the correct java command to run it as if it was the jar?
Meaning, what would be the equivalent command to java -jar myProgram.jar except not using the jar itself?
I've tried stuff like java -cp ".;META-INF\lib\*" JarMain but it seems like there's still something missing there.

Do you mean that add a jar to classpath but do not run it? If so, java -cp myProgram.jar;ohterjar/libdir JarMain. If you use linux/mac,replace ; to :.

If you run jar file directly (without extracting), you can use command: java -jar jarfilename. jar
If you extract jar file into separated files, you can run .class file only. Use the command java classfilename.
You need to set path environment to java/bin directory before running above commands, or just change directory to it.

using Jar file in java code

I am coding in simple text document and executing java code with command line with javac command. i want to use jar file which is in directory like /abc/public/assi1 and i have code which is in directory like /abc/assi1. I am including the jar file with import statement in the class myClass.java which is in directory /abc/assi1/myClass.java i am getting errors.
It is not recognizing the things which are in the jar file.
Could some one please help in this.
Thanks

You can compile your code like this from the directory /abc/assi1:
javac -cp .:/abc/public/assi1/your.jar -d . your-java-class.java
Then you can run your code like this from the directory /abc/assi1:
java -cp .:/abc/public/assi1/your.jar your-java-class
-cp option sets the class path for you on command line. It adds the required jar file and the current directory . into your class path.

The jar has to be inside your java path.
You have to write something like this.
javac -classpath \path\to\lib.jar src.java

How to include jar files with java file and compile in command prompt

I have 3 jar files and a .java file that depends on these jar files. How do I compile the .java file with these jar files using a command prompt?

You can include your jar files in the "javac" command using the "-cp" option.
javac -cp ".:/home/path/mail.jar:/home/path/servlet.jar;" MyJavaFile.java
Instead of "-cp" you could also use "-classpath"
javac -classpath ".:/home/path/mail.jar:/home/path/servlet.jar:" MyJavaFile.java
You could including the jars every time you compile by setting the environment variable "CLASSPATH" correctly. The environment variable will store the path where the jars and classes that needs to be used for compiling/executing any java file. You will not have to include the jars individually every time you compile you file.
Different machines have different methods to set the classpath as an environment variable.
The commands for Windows, Linux, etc are different.
You can find more details in this blog.
http://javarevisited.blogspot.com/2011/01/how-classpath-work-in-java.html

Please try on Linux
javac -cp jarfile source file
EXAMPLE :-
javac -cp .:/jars/* com/template/*.java

Syntax will work on windows dos command:
javac -cp ".;first.jar;second.jar;third.jar" MyJavaFile.java

The followings are steps,
Copy all jars and your .java file in a same folder (It will be easy to mention file names instead of mentioning long path. Though you can keep jar and .java in separate folders).
To compile,
javac -cp .:<file_1_name>.jar:<file_2_name>.jar <prog_name>.java
To execute,
java -cp .:<file_1_name>.jar:<file_2_name>.jar <prog_name>
I hope this helps!

Try to add all dependency jar files to your class path through environment variable settings or use the below steps:
Open command prompt.
Change directory to the location of you java
file that you would like compile.
Set the classpath for your dependency jar files as shown below:
set classpath=C:\Users\sarath_sivan\Desktop\jars\servlet-api.jar; C:\Users\sarath_sivan\Desktop\jars\spring-jdbc-3.0.2.RELEASE; C:\Users\sarath_sivan\Desktop\jars\spring-aop-3.0.2.RELEASE;
Now, you may compile your java file. (command: javac YourJavaFile.java)
Hope this will resolve your dependency issue.

This will create .class file:
javac -classpath "[jarname with specified path]" [java filename]
This will execute class file:
java -cp [jarname with specified path]: [java filename]

Try This.
javac -cp .:jars/jar1:jars/jar2:jars/jar3 com/source/*.java

javac -cp jars/jar1:jars/jar2:jars/jar3 abc.java
With -cp command we specify the path where to find the additional libraries which are required to compile the class. jar1, jar2 and jar3, available in jars folder are used to compile abc.java class.

You need to specify the dependencies in compile time as well as runtime
To compile use this format
javac -cp "*.jar;classfile_path" filename.java
Example:
javac -cp "ojdbc6.jar;c:\programs" Main.java

some times making following change works:
java -cp ".;%CLASSPATH%" classfilename
Note: ON Windows. For linux use $CLASSPATH instead.

If you are using Ubuntu:
/opt/JavaServices/sqlite $ export CLASSPATH=/opt/JarFiles/XXXX.jar:/opt/JarFiles/XXXX.jar:/opt/JavaServices/;javac SQLiteSample.java
Go to folder location (Out of package structure)
/opt/JavaServices $ export CLASSPATH=/opt/JarFiles/XXXXX.jar:/opt/JarFiles/XXXXX.jar:/opt/JavaServices/;java sqlite.SQLiteSample
Note: Please see the file locations and package names

Plenty of these answers helped me, but none that were exactly what I needed.
Assumptions:
Windows OS
JAR file and java file are in same directory
javac -cp <jar filename>.jar <filename>.java
java -cp <jar filename>.jar; <filename>
Keep in mind the syntax needs to exactly match. Cannot exclude file extensions or the semi colon.

Jar file not working correctly

I create .jar file in eclipse. I use .jar file to print text on pos printer. My program is printing correctly, but when I start .jar file is not connecting with the printer. For connecting with the printer I use javax.comm library.

Open up the jar in achiever tool edit Menifest.txt add the following
Class-Path: /path/to/requiredLibary.jar
Also See
Adding Classes to the JAR File's Classpath

Is the javax.comm jar in the classpath when you start the jar from the command line?
Something like:
java -cp myproject.jar;javax-comm-3.0.jar com.mycompany.MyMainClass
Note that the java -jar myproject.jar is incompatible with -cp, ie this doesn't work: java -cp javax-comm-3.0.jar -jar myproject.jar

Why has it failed to load main-class manifest attribute from a JAR file?

I have created a JAR file in this way jar cf jar-file input-files. Now, I'm trying to run it. Running it does not work (jre command is not found):
jre -cp app.jar MainClass
This does not work either:
java -jar main.jar
(Failed to load Main-Class manifest attribute from main.jar).
I also found out that
To run an application packaged as a
JAR file (version 1.2 -- requires
Main-Class manifest header)
What is the "Main-Class manifest header"? How do I create it and where do I put it?

I'm not sure I believe your symptoms:
If the jre command isn't found, then running jre -cp app.jar should give the same error
Just adding a JAR file to the classpath shouldn't give the error you're seeing
I'd expect you to see this error if you run:
java -jar app.jar
The Main-Class header needs to be in the manifest for the JAR file - this is metadata about things like other required libraries. See the Sun documentation for how to create an appropriate manifest. Basically you need to create a text file which includes a line like this:
Main-Class: MainClass
Then run
jar cfm app.jar manifest.txt *.class

set the classpath and compile
javac -classpath "C:\Program Files\Java\jdk1.6.0_updateVersion\tools.jar" yourApp.java
create manifest.txt
Main-Class: yourApp newline
create yourApp.jar
jar cvf0m yourApp.jar manifest.txt yourApp.class
run yourApp.jar
java -jar yourApp.jar

You can run with:
java -cp .;app.jar package.MainClass
It works for me if there is no manifest in the JAR file.

I got this error, and it was because I had the arguments in the wrong order:
CORRECT
java maui.main.Examples tagging -jar maui-1.0.jar
WRONG
java -jar maui-1.0.jar maui.main.Examples tagging

The easiest way to be sure that you have created the runnable JAR file correctly, with the appropriate manifest file, is to use Eclipse to build it for you. In your Eclipse project, you basically just select File/Export from the menu, and follow the prompts.
That way, you can be sure that your JAR file is correct and will know to look elsewhere if there is still an issue. The process is described in full in FAQ How do I create an executable JAR file for a stand-alone SWT program?.

I was getting the same error when i ran:
jar cvfm test.jar Test.class Manifest.txt
What resolved it was this:
jar cvfm test.jar Manifest.txt Test.class
My manifest has the entry point as given in oracle docs (make sure there is a new line character at the end of the file):
Main-Class: Test

Try
java -cp .:mail-1.4.1.jar JavaxMailHTML
no need to have manifest file.

I discovered that I was also having this error in NetBeans.
I hope the following is helpful.
Make sure that when you go to Project Configuration you set the main class you intend for running.
Do a Build or Clean Build
Place the jar file where you wish and try: java -jar "YourProject.jar" again at the command line.
This was the problem I was getting because I had other "test" programs I was using in NetBeans and I had to make sure the Main Class under the Run portion of the Project configuration was set correctly.
many blessings,
John P

I faced the same problem. This unix command is not able to find the main class. This is because the runtime and compile time JDK versions are different. Make the jar through eclipse after changing the java compiler version. The following link helped me.
http://crunchify.com/exception-in-thread-main-java-lang-unsupportedclassversionerror-comcrunchifymain-unsupported-major-minor-version-51-0/
Try running the jar created after this step and then execute it

If your class path is fully specified in manifest,
maybe you need the last version of java runtime environment.
My problem fixed when i reinstalled the jre 8.

If you using eclipse, try below:
1. Right click on the project -> select Export
2. Select Runnable Jar file in the select an export destination
3. Enter jar's name and Select "Package required ... " (second radio button) -> Finish
Hope this helps...!