Checking the installed java version. Installation and launch

Hi all! Today I will try to write a large-scale article about Java. After all, many applications now use it.

And during work, sometimes errors arise.

Java - what is it and what is this program for?

Java is a programming language or technology in which online applications are written. Those. chats on websites, games, downloading files (including photos, videos) and many other things.

The advantage of this technology:

1. Independence of code, operating system and devices i.e. this allows you to run applications on any device, regardless of the operating system;
2. And security (this is most likely why many banks use it when connecting), because if the operation exceeds the authority, an immediate interruption will occur.

One of the shortcomings is the speed of execution, although there have been improvements.

There may be more, but these are the main official sources.

Here's the story:

How to update Java to the latest version (or install)

In order to update java (or install) you need to go to the official website of the application. And click download java.

And one more thing... In browsers that are developed on the Chromium engine, java may not work. If the version is old, you can try in the address bar by entering chrome://flags/#enable-npapi next paragraph " Enable NPAPI."

But most likely, you will have to download an old version of the browser, look for add-ons, or use Intenet Explorer.

Installation is simple, just click install.

You can also update through the control panel:

And in the application there is an Update tab.

By the way, here are the instructions for enabling it in browsers.

How to check Java version

To check the version, you can also go to the control panel, select java.

About button.

In the window that opens we see the version.

How to remove Java

Java is removed in the usual way, through the program uninstaller, but if you were unable to remove it, then use the utility.

This is what uninstallation looks like using JavaUninstallTool.

Errors that occur when running Java

Here I will try to analyze common mistakes when working. If suddenly you had errors and you solved them, do not hesitate to write in the comments, we will help each other, so to speak...

Java applet not loaded

To begin, follow the usual steps, make sure that the required version of java is installed and that the firewall is not blocking it. Reboot your computer and router. Next, if all else fails, go to the control panel and select java.

If you use a proxy, then you need to register the proxy in General - Network Settings - Use proxy server.

There are also cases when it is necessary not to store temporary java files on the computer, but to store them on a bank server, for example, but this is an individual situation. In such situations, you need to read the instructions on bank websites. And in general, always, if you configure java for a bank, then read the individual instructions of the bank.

Error 1603: Java update not completed

In this situation, uninstall java using the application or you can try manually through the control panel. Then install again.

Java won't install

• Here, also try to uninstall if there is an old version and reinstall it. When installing, try installing as an administrator.
• Make sure you have full access to all folders.
• Download the offline installer and try installing it.
• If all else fails, make sure that nothing is preventing the installation, for example: antivirus, firewall.
• All applications require the NET Framework and Microsoft Visual C++, try updating them.

Not an internal or external command

In this error, we copy the path to the program, for me it is: C:\Program Files (x86)\Java\jre1.8.0_144\bin

We look for PATH and click edit.

Be careful here now!

For example, here is my piece of code: C:\ProgramData\Oracle\Java\javapath;C:\Program Files (x86)\Intel\iCLS Client\;C:\Program Files\Intel\iCLS Client\;

Those. each parameter must be separated by a semicolon. If you are not confident in your abilities, copy this line somewhere just in case.

So what we do:

1. Go to the end of the line
2. If there is no semicolon, we put it, if there is, we write our path C:\Program Files (x86)\Java\jre1.8.0_144\bin (your path should be here) and put a semicolon at the end.

You can also try this path: C:\ProgramData\Oracle\Java\javapath;

(eventually getting to the point where I can write simple small programs for Android or the web) but I managed to get java running on my computer (from past experiments).

I'm not sure what version of java I have and would like to know if there is a command to see the installed and active version of Java. Also, which version works best? All this on 32-bit Ubuntu 12.04

EDIT:
So it looks like I have 6 and 7, when using open 7. I want to use openjdk 7, so how do I uninstall openjdk 6? Is just via USC good enough or is there a command that needs to be run?

Related of "How do I know what version of Java I have installed?"

This command should tell you what the java virtual machine (java) and Java compiler (javac) currently provide:

File /etc/alternatives/java /etc/alternatives/javac

This assumes that the "alternative" system is working as expected, which it may not be, depending on how Java has "messed up" in the past. To check this, run:

File `which java javac`

If the alternatives system is working correctly and Java is being used, you should see:

/usr/bin/java: symbolic link to `/etc/alternatives/java" /usr/bin/javac: symbolic link to `/etc/alternatives/javac"

Otherwise edit your question, to provide detailed information. Then it should be possible to give a more specific answer.

You can uninstall openjdk-6 using Software Center. There are multiple packages associated with it, so you may need to remove multiple packages. (All openjdk-6 packages are listed here.)

Or you can use the command line:

Sudo apt-get remove openjdk-6-\* icedtea-6-\*

However, whichever method you use, you may want to check first to see what depends on those packages. You may have software installed that needs version 6. (Probably not, but possible.)

You can check this, by modeling delete operation on the command line:

Apt-get -s remove openjdk-6-\* icedtea-6-\*

This will show you the effects of removing those packages, including other packages that were removed. (You'll notice that since this is a simulation, you don't need sudo .)

If you want to continue using Java content online in your web browser (this is not the same as JavaScript), before removing any icedtea-6- or openjdk-6- packages (except possibly openjdk-6-jdk), you must ensure that you have icedtea-7 packages installed that match all icedtea-6 packages installed.

The easiest way:

update-java-alternatives -l shows all versions of Java you have installed.

java -version shows you the version of Java being used.

java -showversion shows you the Java version you are using and help.

Typically this will be OpenJDK.

Java -version javac -version

These commands display the version of java (the interpreter that runs Java programs) and javac (the compiler that creates them).

See the image above for details.

This is what I did, it worked for me:

Open a terminal:

control + alt + T

Then enter (or copy and paste from here) these commands one at a time:

Sudo rm /var/lib/dpkg/info/oracle-java7-installer* sudo apt-get purge oracle-java7-installer* sudo rm /etc/apt/sources.list.d/*java* sudo apt-get update sudo add-apt-repository ppa:webupd8team/java sudo apt-get update sudo apt-get install oracle-java7-installer

Then, to be on the safe side, I would reboot.

To find your java version type

Java -version

and you should see output like this:

Java version "1.7.0_04" Java(TM) SE Runtime Environment (build 1.7.0_04-b20) Java HotSpot(TM) 64-Bit Server VM (build 23.0-b21, mixed mode)

Although yours will be in 32 bit.

I highly recommend using Java 7, but updates will also try to install Java 6. That's fine. But your default should still appear as 7. Everything I chose works as long as your video card drivers are working.

• Are PPAs safe to add to my system and what are the red flags to watch out for?

Step-by-step instructions on how to check the installed version of Java on Windows or Mac.

Works on operating systems Windows 10, Windows 7, Windows 8, Windows XP, Windows Vista, macOS, Mac OS X.

The instructions work with versions of Java 7.0 and Java 8.0.

The installed version of Java can be found:

1. 1.In the Start menu (for Windows)
2. 2.Windows Control Panel → in the "Programs" section
3. 3.In the Java Control Panel (Windows and Mac)
4. 4.Terminal window → in the command line (for Mac)

Let's take a closer look at each of the above points.

Search for Java version in the Start menu

This method can be used to find Java 7 (Update 40) and later versions.

1. Open the Start menu
2. Click on Programs
3. Finding a list of Java programs
4. To display information about the current version of Java, click About Java

Find the Java version in the Programs section of Control Panel

The installed Java version information will also include the update number. For example: Java 8 Update 110. Previous versions of Java are usually reported as Java(TM), Java Runtime Environment, Java SE, J2SE, or Java 2.

Search for Java version in the "Programs" section for Windows 10

1. Open the Start menu
2. We find it in the list of Java programs
3. Click on the Java folder
4. Select the item About Java (About Java)

Search for Java version in the "Programs" section for Windows 8

1. Right-click in the lower left corner of the screen
2. In the menu that opens, click on Control Panel
3. Then in the control panel select the Programs section
4. Click on Programs and Features

Search for Java version in the "Programs" section for Windows 7 and Vista

1. Go to the Start menu
2. Open the Control Panel
3. Select the Programs section
4. Open Programs and Features
5. After which a list of Java versions installed on your computer will be displayed.

Search for the Java version in the "Programs" section for Windows XP

1. Go to the Start menu
2. Open the Control Panel
3. Click on the Add or Remove Programs icon
4. After which a list of programs installed on your computer will be displayed, including installed versions of Java

Finding the Java version in the Java Control Panel (Windows and Mac)

1. Open the Control Panel
2. Go to the About section on the General tab. After which a window will appear with information about the installed version of Java.

Finding the Java version in the command line of a terminal window (for Mac)

To use this search method, you must download the Java Development Kit (JDK). The Java Runtime Environment (JRE) can work in conjunction with the JDK.

1. Open a terminal window
2. Enter the following command:

   /Library/Internet\ Plug-Ins/JavaAppletPlugin.plugin/Contents/Home/bin/java -version

If you need to determine which version of the JDK is installed on your device, then follow these steps:

1. Open a terminal window
2. Enter the command: