What is a JAR file?
In a simple word a jar file is a Java ARchive file, which is a package file format typically used to aggregate many Java class files and associated Metadata and resources like text, images, etc. into one single file for distribution. Like their name, these are the archive files that contain a Java-specific manifest file which is built on the ZIP format and mainly have a.JAR file extension. A JAR file allows Java runtime to efficiently deploy an entire application, containing its classes and their associated resources, in just one single request. The elements of JAR files can be compressed, shortening downloading times.
A JAR file includes all components that make up a executable Java application, deployable Java applet, or mainly a Java library to which any Java Runtime environment can link. Two key benefits are there of using a JAR file. The first benefit is the ability, to sum up, hundreds, if not thousands, of different files that make up an application. The next one is the means to compress all of the included files, significantly reducing the size of the program, and making it easier to move the JAR file over a network and between environments.
How to open a JAR file?
To open a JAR file in your windows, it is a must to have the Java Runtime Environment installed on your computer. Also, you can use the decompression software, like an Unzip utility, to view the files in the JAR archive. If the JAR file opens using an archive program like WinRAR or 7-Zip, and you want it to begin with Java instead of it then follow the instructions given below:
- First you have to open file with “open with” option
- Now click on the Browse button to open the file explorer window.
- Firstly find out the Java executable file on your personal computer hard drive.
- Select subfolder below the java folder.
- Click on OK.
We are importing Java Projects as JAR files in Eclipse.
It is the most convenient method to archive a Java Project is to store it in a JAR file that is more like the Zip files, that permits you to group several files into one. These JAR files are also the best way of packaging projects to be run as applets within a browser Eclipse is the software that allows you to both export projects into JAR files and to import a Java project from a JAR file.
- Start Eclipse and then browse to your workspace.
- Make a new project.
- Expand the project name in the package explorer and left-tap on the src folder.
- Right-tap on the src folder and then select the import.
- In the dialogue box,f import it expands General and then selects the archive file.
- Click on the Next.
- Browse the JAR file that wishes to import and then click on the open command.
- Another import dialogue box gets opens and shows you what is present in your JAR file.
- Click on the finish button, and the files should import correctly.
How to convert JAR file?
- Firstly start your Eclipse program and browse to your workspace.
- In the Package Explorer, just left-tap on the project that you wish to export.
- Right-tap on the same project and select the Export.
- When the dialogue box of Export appears, it expands Java and then click on the JAR file and then click on the Next button.
- The JAR file Export dialogue box appears. Check the 2nd, 3rd, and 4th export checkboxes as I have made for my project.
- Browse to generate a name and search a location for your JAR file.
- Click on the Finish button, and your JAR file will be generated in the location you have selected.