How to open jar file

How to open a jar file

To open a jar file in Windows, you must have the Java Runtime Environment installed. Alternatively, you can use decompression software, such as an unzip utility, to view the files in the jar archive.

To run the file (Java Runtime Environment)

To run the jar file, you need to download and install the Java Runtime Environment (if you do not have it already) from the link below.

Once downloaded, you can run any jar file by double clicking the file name. Keep in mind that this only works if the jar file to be opened is executable. If it’s not executable, you can view files within it instead.

If double-clicking the jar file does not result in the file being run, it’s likely not an executable file and cannot run in this manner. Read the next section on how to view the contents of the jar file.

If the jar file opens using an archive program, such as WinRAR or 7-Zip, and you want Java to open it instead, follow the instructions below. (The jar file must contain executable Java code for these steps to work.)

To view the file (decompression)

To view individual files in a non-executable jar file, you can obtain compression/decompression software that works with jar files. We recommend using either 7-Zip or WinRAR.

Once you have installed this software, run the software, open the jar file, and extract the files contained in it. Once the files are extracted, you can view the individual files by double clicking them. Many of those files are probably text files, but others may require additional software to view them.

If the jar file defaults to be opened with an archive program, such as WinRAR or 7-Zip, you can change the default program. To change the default program that opens jar files, right-click the jar file, select Open With, then Choose default program. In the Open With window, click the Browse button to open the File Explorer window. You need to find the executable file (.exe file) for the software program you want to set as the default program to open the jar file.

How to run a JAR file on Windows 10/11 [Quick guide]

In case of not knowing, a JAR file is a Java archive package format that might include a Java program within it.

While you can extract JARs with archiving software, you can’t run a pure Java JAR app as you would with other programs in Windows.

Since that’s the case, we’ll cover how you can run a pure Java app JAR file in Windows.

How are JAR files helping you?

A JAR file allows Java runtimes to enclose an entire application, together with its classes and resources, in a single source.

Moreover, the elements inside a JAR file can be compressed, and that translates by shorter download times but also less space allocated on your drive.

In fewer words, JARs are more sophisticated archives that work in a Java environment on your PC.

How can I run a JAR file on Windows 10?

1. Add Java to Windows

The crucial thing you need upfront is to have Java installed. Without it, Java apps aren’t going to run in Windows.

2. Use Java (TM) Platform SE binary

3. Download a JAR file opener

You can open JAR files with a lot of apps out there but we strongly recommend File Viewer Plus because it can open and display over 300 different file types.

The new updated version has a plethora of features that will save you big time on opening, viewing, or editing files.

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Keep in mind that the app supports the most popular text, audio, or video file type, as well as archive, source code, or web files.

4. Run a JAR file from the Windows Command Prompt

That will open the executable JAR file so long as it contains a manifest file to specify the application’s entry point (the developers should have already included that in the archive.)

If you develop your own Java programs, you’ll need to convert the JAR to an executable format.

The command-lie app is crucial for debugging and installing apps but if it doesn’t work, learn how you can fix Command Prompt in Windows.

5. Add a third-party JAR executor to Windows

There are also executor programs for Windows like JARX that enable you to run JAR files the same as any other program.

How to get a JAR file for your favorite app?

There are lots of websites that offer free JAR versions of any application you can think of and we’re going to provide a simple example for Instagram.

We hope that our guide helped you with all the information needed to run JAR files in Windows or even convert them if needed.

If you have any other suggestions or questions, leave them in the comments section below and we’ll be sure to take a look.

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What Is a JAR File?

How to open, edit, and convert JAR files

What to Know

This article explains what a JAR file is, the different ways you can open one depending on how you want to use it, and how to convert one to EXE or ZIP.

What Is a JAR File?

JAR files are ZIP compressed and often store things like CLASS files, a manifest file, and application resources like images, sound clips, and security certificates. Since they can hold hundreds or even thousands of files in a compressed format, it’s easy to share and move them.

Java-capable mobile devices might use this format for game files, and some web browsers hold themes and add-ons in the JAR format.

How to Open JAR Files

The Java Runtime Environment (JRE) must be installed in order to open executable JAR files, but note that not all JAR files are executables. Once installed, you can just double-click the file to open it.

Some mobile devices have JRE built-in. Once installed, Java applications can be opened in a web browser, too, like Firefox, Safari, Edge, etc. (but not Chrome).

Since JAR files are compressed with ZIP, any file decompressor can open one to see the contents that are inside. This includes programs like 7-Zip, PeaZip and jZip

Another way to open the file is to use the following command in Command Prompt, replacing yourfile.jar with the name of your own JAR file:

Since you might need different programs to open different JAR files, see How to Change the Default Program for a Specific File Extension in Windows if it’s automatically opening in a program that you don’t want to use it with.

Errors Opening JAR Files

Because of security settings in the Windows operating system and within some web browsers, it’s not at all uncommon to see errors when attempting to access Java applications.

For example, «Java Application Blocked» might be seen when trying to load a Java applet. «Your security settings have blocked an untrusted application from running.» can be fixed by setting the security level within the Java Control Panel applet.

If you can’t open Java applets even after installing JRE, first make sure Java is enabled in your browser and that Control Panel is properly set up to use Java. Then, completely restart your browser by closing down all open windows and then reopening the whole program.

Also, check that you’re running the latest version of Java. If you’re not, return to that JRE link above and install the latest version. Or, learn how to update your current Java installation.

Although unlikely, you might be receiving errors because you don’t really have a JAR file, and so the program you’re using to open it doesn’t support the format. This can happen if you’ve misread the file extension. There’s more on this below.

How to Convert a JAR File

You can decompile a JAR file’s CLASS files to Java files with the help of JavaDecompilers.com. Upload your file there and choose which decompiler to use.

Converting a Java application so that it can be used on the Android platform would require a JAR to APK file conversion. One option might be to run the JAR file in an Android emulator so that the program creates an APK file automatically. However, it seems that the easiest way to get a Java program on Android is to simply compile the APK from the original source code.

You can make executable JAR files in programming applications like Eclipse.

WAR files are Java Web Archive files, but you can’t convert a JAR file directly to a WAR file, since the WAR format has a particular structure that JARs do not. Instead, you can build a WAR and then add the JAR file into the lib directory so that the classes inside the JAR file are available for use. WizToWar might help you do this.

Still Can’t Open It?

Some files share a few of the same file extension letters, which can cause confusion if the file isn’t opening like you think it should. What’s happening is that you’re most likely misreading the file extension.

For example, JARVIS files open with a text editor, and JARC and ARJ files are archives.

More Information on the JAR Format

If you need help packing programs into JAR files, follow that link for instructions on the Oracle website.

Only one manifest file can be included in a JAR archive, and it has to be at the META-INF/MANIFEST.MF location. It should follow the syntax of the name and value separated by a colon, like Manifest-Version: 1.0. This MF file can specify the classes the application should load.

Java developers can digitally sign their applications, but it doesn’t sign the JAR file itself. Instead, the files inside the archive are listed with their signed checksums.

How to Open a JAR File in Windows, Online

Updated July 4, 2022

What is a JAR File?

A JAR file contains the various components of an executable Java application. Files with JAR extensions store multiple Java programs in one single File. Some JAR files work as standalone apps, while others hold program libraries to be used by other applications.

How to Install and Run Java Runtime Environment (JRE)

You need a Java Runtime Environment(JRE) to run a JAR file format. If you already have JRE installed in your system, you only need to double-click the JAR file, and it will start running.

Note: Java Runtime Environment only works with executable JAR file formats; if your files are not in this format, you can only view them.

Here’s is the step-by-step process to install the Java Runtime app on your computer:

Step 1) Find JRE from its official download page.

Find the latest version of Java Runtime Environment from the official download page.

Step 2) Select the version that meets your system requirement and click download.

You should select a version that suits your PC specifications and click it to begin downloading. In this case, we selected Windows offline (64-bit)

Downloaded files are found in the download files folder on your PC.

Step 4) Install JRE

Installation takes a few seconds. Check the green bar on your screen to view the installation progress.

Step 5) Click the Close button

Once the green bar is full, that means installation is now complete. Notice the message “You have successfully installed Java” on your screen.

How to Run JAR Files on Windows 10

To run an application or code in a JAR file on Windows 10, you need to have JRE installed. There are several ways of running JAR files.

Here are two of them.

How to run JAR File using Java Runtime Environment

Following are the steps to run JAR files using Java Runtime Environment:

Step 1) Right-click on the JAR file

Select “open with.” You’ll be directed to a dialogue box, tap” Choose Another App.”

Step 2) Click “More Apps”

You’ll see a dialogue box “How do you want to open this file?” Scroll down to the last option and select Click “More Apps”.

Step 3) Select “Look for more apps on this PC.”

Once you click on another app on the PC, you’ll be directed to the programs folder on Local Disk C.

Step 4) Tap on the Java folder

To find Java in programs File. Open Local Disk C>Program files> Java> JRE 1.8.0> bin. Click to set Java.exe as default.

How to run JAR File using the command prompt

Here are the steps to run JAR files using the Command prompt:

Step 1) Open Command Prompt

Then press the Windows key and type “cmd” on your keyboard. You will be directed to a command prompt option. Run as administrator.

Enter the command prompt where “pathtofile” is the path of the file in question.

Step 3) Run the command.

Windows will interpret the JAR file using JRE. You will now see the Java application running.

How to Open JAR Files Online

Opening via the web is the easiest way to open JAR files. There are a range of online tools that you can use to open JAR files. Most have similar steps.

Here’s how to open JAR files online using online extractor tools:

Step 1) Find a tool online and upload files

Google search “online tools for opening JAR files.” Select your tool of choice, then upload the files you want to open.

Step 2) Click On Download as a Zip option.

After uploading, some tools will ask to extract files. Others will already have the files extracted, like in this case.

Software Tools for Opening JAR Files

1) WinRAR

WinRAR is best known for efficiently compressing large file formats besides Windows. It is ideal for extracting JAR archive formats because it’s free to download and has an easy-to-use interface.

WinRAR integrates with the operating system’s UI to allow instant archiving and extraction tools access. It works at breakneck speeds that will enable compressing and decompressing of large data in short periods.

2) 7-Zip

7-Zip is open source and is widely used for compressing and archiving data. This archive viewer and extractor tool is similar to WinRAR, except for the open-source part, and can be used to open JAR files.

7-Zip is ideal for coders dealing with JAR files. It comes with a traditional UI and has been around for a while. Coders can tweak the archiving using complex commands that they can input into the console.

3) WinZip

WinZip is an easy-to-use tool that allows users to compress and decompress files. It helps you open and extract data from JAR files and arch it back into any archive format. It comes with secure encryption and is one of the most popular apps for opening JAR files.

Users love its versatility and efficiency.

4) File Viewer Plus

File Viewer Plus is a universal file opener that can open more than 300 types of files. In Windows operating system, users can save, convert, view, and edit files using File Viewer Plus.

File Viewer Plus allows you to create a variety of multimedia formats, edit, and save documents and images. You can also convert files into many formats and inspect file contents using File Viewer Plus.

5) UltimateZip

UltimateZip allows users to read and compress zip files easily. It allows convenient compression and extraction of archived files. UltimateZip works on a range of archive file formats, including JAR files. It comes with software protection ability thanks to its AES 256-bit protection. The software also has cloud support services.

Converting a JAR File into an Executable File

Here’s how you can convert JAR into an executable file using Launch4J.

Step 1) Download Launch4J and install it

The first step is to download a wrapper for converting JAR files into windows executable files (.exe). In this case, we’ll be using Launch4J. Download the latest version online, install and launch it.

Step 2) Enter basic configurations

On the Basic tab after launching the Launch4J app, add your path to the Output file by selecting where you want to save it.

Step 3) Click the JRE tab

Add the minimum JRE version to the minimum section on the JRE tab. For this piece, we added 1.7.0 as our minimum JRE version.

Now click the gear icon for ‘build’ to run it.

How to fix the “Cannot Open JAR Files in Windows” Issue

If you’re experiencing the “cannot open JAR files” issue on your windows PC, below are quick solutions to this problem.

1) Update the Java Runtime Environment

One of the problems that could be causing an issue with accessing JAR files on windows is an outdated version of JRE.

Here are steps to update the Java Runtime Environment:

Step 1) Open the control panel

Open the control panel by tapping the windows icon and typing “control panel.” If you have the icon on your desktop, you can click it directly.

Step 2) Double click Java icon on the control panel

The settings are organized alphabetically, so it should be easy to locate Java. Once you’ve found it, just double-click to open it.

Step 3) Tap “Update Now” on the update tab of the Java Control Panel

After double-clicking on the java control panel, a pop-up setting will appear. Tap on the update tab of the Java control panel, then click “Update Now”.

Now, another way to update JRE is by uninstalling the current version and installing the latest version.

2) Set JRE as the default app

You can do this quickly by right-clicking on any space within the folder and selecting New> Text Document.

Now, replace the filename.jar with the actual name of the Jar file.

Step 3) Select “Save As Type” and choose “All Files”

Разархивация и запуск файлов JAR

JAR (Java Archive File) – формат архива, в котором хранятся элементы программы, написанной на языке Java. Чаще всего файлы с таким расширением являются мобильными играми и приложениями. На компьютере можно просмотреть содержимое такого архива и/или попытаться запустить JAR как приложение.

Способы открытия JAR-архива

Для начала рассмотрим несколько программ для открытия архива JAR. Так можно убедиться, что в нём содержится всё необходимое для запуска этого приложения, а также внести требуемые изменения.

Способ 1: WinRAR

Когда речь заходит об архивах, большинству пользователей приходит на ум программа WinRAR. Для открытия файла JAR она отлично подходит.

Обратите внимание на наличие папки «META-INF» и файла «MANIFEST.MF», который должен храниться в ней. Это позволит реализовать файл JAR в качестве исполняемого.

Найти и открыть нужный архив можно и через встроенный обозреватель файлов WinRAR.

Если с содержимым архива планируется дальнейшая работа, то потребуется разархивация.

Способ 2: 7-Zip

Поддержка расширения JAR предусмотрена и в архиваторе 7-Zip.

Способ 3: Total Commander

Альтернативой упомянутым программам может стать файловый менеджер Total Commander. Т.к. его функционал включает работу с архивами, открыть JAR-файл будет несложно.

Способы запуска JAR на компьютере

При необходимости запустить приложение или игру JAR понадобится один из специальных эмуляторов.

Способ 1: KEmulator

Программа KEmulator – это продвинутый Java-эмулятор, позволяющий произвести настройку всевозможных параметров запуска приложения.

Или перенесите этот файл окно программы.

На мобильных телефонах управление осуществлялось с помощью клавиатуры. В KEmulator можно включить её виртуальный аналог: нажмите «Справка» и выберите пункт «Клавиатура».

Выглядеть это будет так:

При желании в настройках программы Вы сможете задать соответствия клавиш телефона клавишам компьютера.

Обратите внимание, что в папке с JAR появится файл «kemulator.cfg», в котором прописаны параметры работы этого приложения. Если его удалить, то все настройки и сохранения (если речь идёт об игре) удалятся.

Способ 2: MidpX

Программа MidpX нет так функциональна, как KEmulator, но со своей задачей справляется.

После установки все файлы JAR будут ассоциироваться с MidpX. Это можно понять по изменившейся иконке:

Дважды кликните по ней и приложение будет запущено. При этом виртуальная клавиатура уже интегрирована в интерфейс программы, однако настроить управление с клавиатуры ПК тут нельзя.

Способ 3: Sjboy Emulator

Ещё один простой вариант для запуска JAR – это Sjboy Emulator. Главная его особенность заключается в возможности выбора скинов.

Клавиатура тут также интегрирована.

Итак, мы выяснили, что JAR можно открыть не только как обычный архив, но и запустить на компьютере через Java-эмулятор. В последнем случае удобнее всего использовать KEmulator, хотя и другие варианты тоже имеют свои преимущества, например, возможность изменять оформление окна.