How to open/run .jar file (double-click not working)?

Question

I can\'t open or run my .jar file.

I just installed java, but I tried to open the .jar with other programs first, so the double-click defaults to something else and

Answer 1

Use cmd prompt and type

java -jar exapmple.jar

To run your jar file.

for more information refer to this link it describes how to properly open the jar file. https://superuser.com/questions/745112/how-do-i-run-a-jar-file-without-installing-java

Answer 2

In cmd you can use the following:

c:\your directory\your folder\build>java -jar yourFile.jar 

However, you need to create you .jar file on your project if you use Netbeans. How just go to Run ->Clean and Build Project(your project name)

Also make sure you project properties Build->Packing has a yourFile.jar and check Build JAR after Compiling check Copy Depentent Libraries

Warning: Make sure your Environmental variables for Java are properly set.

Old way to compile and run a Java File from the command prompt (cmd)

Compiling: c:\>javac Myclass.java
Running: c:\>java com.myPackage.Myclass

I hope this info help.

Answer 3

Short trick: after I only REMOVED SPACES from names of the folders, where the .jar file was, double-clicked worked and the file executed.

Answer 4

You must create a manifest file and specify your class that has the main method. you can build your jar file with manifest file as a parameter.

jar cfm MyJar.jar Manifest.txt MyPackage/*.class

Manifest-Version: 1.0

Archiver-Version: Plexus Archiver

Created-By: Apache Maven

Built-By: Cakes

Build-Jdk: 1.6.0_04

Main-Class: com.foo.App

Answer 5

I had this problem a while back and the solution was really easy.

Just uninstall the current version of Java, download an older one, then uninstall the older and install the latest again.

For example: Java 8 Update 73 current install Java 7 Update 95.

How it works: Java's registry keys were messed up, and when you install the older version they get fixed.

Answer 6

Go to your java directory, Copy this path C:\Program Files\Java\jdk1.8.0_40\bin

Right click on my computer , click properties, then go to "Advanced system settings" click , Environment variables. go to "System variables" table, find an entry named "path". Double click it and go to the end, put a semicolon and paste your path, apply and ok. It should run now.