Windows java jvm path

How to set JAVA_HOME environment variable on Windows 10

In this article, you will understand the details about JAVA_HOME environment variable and how to set it on Windows 10.

What is JAVA_HOME?

By convention, JAVA_HOME is the name of an environment variable on the operating system that points to the installation directory of JDK (Java Development Kit) or JRE (Java Runtime Environment) – thus the name Java Home. For example:

JAVA_HOME = c:\Program Files\Java\jdk1.8.0_201

Why is JAVA_HOME needed?

To develop Java applications, you need to update the PATH environment variable of the operating system so development tools like Eclipse, NetBeans, Tomcat… can be executed because these programs need JDK/JRE to function. So the PATH environment variable should include JAVA_HOME :

PATH = Other Paths + JAVA_HOME

Other paths are set by various programs installed in the operating system. If the PATH environment variable doesn’t contain a path to JRE/JDK, a Java-based program might not be able to run. For example, typing java in the command prompt showing this error:

'java' is not recognized as an internal or external command, operable program or batch file.

Or Eclipse will fail to launch:

How to set JAVA_HOME on Windows 10

Here are the visual steps to properly set value for the JAVA_HOME and update the PATH environment variables in order to setup Java development environment on your computer:

1. Firstly, you need to identify the Java home directory, which is typically under C:\Program Files\Java directory. Open My Computer and navigate to this directory, you will see:

Here, the home of JDK is under C:\Program Files\Java\jdk1.80_201 . The version number may vary, depending on the JDK you installed.

2. Open the System Environment Variables dialog by typing environment in the search area on Start menu. Click the suggested item Edit the system environment variables:

The System Properties dialog appears, click the button Environment Variables.

Then you will see this dialog:

3.Create the JAVA_HOME environment variable by clicking the New button at the bottom. In the New System Variable form, enter the name and value as follows:

Click OK, and you will see the JAVA_HOME variable is added to the list.

4.Update the PATH system variable. In the Environment Variables dialog, select the Path variable and click Edit:

Then in the Edit environment variable dialog, double click on the empty row just below the last text line, and enter %JAVA_HOME%\bin as follows:

The percent signs tell Windows that it refers to a variable – JAVA_HOME , and the \bin specifies the location of java.exe and javac.exe programs which are used to run and compile Java programs, as well as other tools in the JDK.

Click OK button to close all the dialogs, and you’re all set. Now you can open Eclipse or NetBeans to verify. Or open a command prompt and type in javac –version , you should see:

You can add the path to the bin directory of Java home directly into the PATH variable. But it’s strongly recommend to follow the above steps to setup a JAVA_HOME variable because many Java programs depend on it.

When you installed a JDK, you might not need to update the system variable because the installer already did it for you.

About the Author:

Nam Ha Minh is certified Java programmer (SCJP and SCWCD). He started programming with Java in the time of Java 1.4 and has been falling in love with Java since then. Make friend with him on Facebook and watch his Java videos you YouTube.

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PATH and CLASSPATH

This section explains how to use the PATH and CLASSPATH environment variables on Microsoft Windows, Solaris, and Linux. Consult the installation instructions included with your installation of the Java Development Kit (JDK) software bundle for current information.

After installing the software, the JDK directory will have the structure shown below.

The bin directory contains both the compiler and the launcher.

Update the PATH Environment Variable (Microsoft Windows)

You can run Java applications just fine without setting the PATH environment variable. Or, you can optionally set it as a convenience.

Set the PATH environment variable if you want to be able to conveniently run the executables ( javac.exe , java.exe , javadoc.exe , and so on) from any directory without having to type the full path of the command. If you do not set the PATH variable, you need to specify the full path to the executable every time you run it, such as:

C:\Java\jdk1.7.0\bin\javac MyClass.java

The PATH environment variable is a series of directories separated by semicolons ( ; ). Microsoft Windows looks for programs in the PATH directories in order, from left to right. You should have only one bin directory for the JDK in the path at a time (those following the first are ignored), so if one is already present, you can update that particular entry.

The following is an example of a PATH environment variable:

C:\Java\jdk1.7.0\bin;C:\Windows\System32\;C:\Windows\;C:\Windows\System32\Wbem

It is useful to set the PATH environment variable permanently so it will persist after rebooting. To make a permanent change to the PATH variable, use the System icon in the Control Panel. The precise procedure varies depending on the version of Windows:

1. Select Start, select Control Panel. double click System, and select the Advanced tab.
2. Click Environment Variables. In the section System Variables, find the PATH environment variable and select it. Click Edit. If the PATH environment variable does not exist, click New .
3. In the Edit System Variable (or New System Variable) window, specify the value of the PATH environment variable. Click OK. Close all remaining windows by clicking OK.

1. From the desktop, right click the My Computer icon.
2. Choose Properties from the context menu.
3. Click the Advanced tab (Advanced system settings link in Vista).
4. Click Environment Variables. In the section System Variables, find the PATH environment variable and select it. Click Edit. If the PATH environment variable does not exist, click New .
5. In the Edit System Variable (or New System Variable) window, specify the value of the PATH environment variable. Click OK. Close all remaining windows by clicking OK.

1. From the desktop, right click the Computer icon.
2. Choose Properties from the context menu.
3. Click the Advanced system settings link.
4. Click Environment Variables. In the section System Variables, find the PATH environment variable and select it. Click Edit. If the PATH environment variable does not exist, click New .
5. In the Edit System Variable (or New System Variable) window, specify the value of the PATH environment variable. Click OK. Close all remaining windows by clicking OK.

Note: You may see a PATH environment variable similar to the following when editing it from the Control Panel:

%JAVA_HOME%\bin;%SystemRoot%\system32;%SystemRoot%;%SystemRoot%\System32\Wbem

Variables enclosed in percentage signs ( % ) are existing environment variables. If one of these variables is listed in the Environment Variables window from the Control Panel (such as JAVA_HOME ), then you can edit its value. If it does not appear, then it is a special environment variable that the operating system has defined. For example, SystemRoot is the location of the Microsoft Windows system folder. To obtain the value of a environment variable, enter the following at a command prompt. (This example obtains the value of the SystemRoot environment variable):

Update the PATH Variable (Solaris and Linux)

You can run the JDK just fine without setting the PATH variable, or you can optionally set it as a convenience. However, you should set the path variable if you want to be able to run the executables ( javac , java , javadoc , and so on) from any directory without having to type the full path of the command. If you do not set the PATH variable, you need to specify the full path to the executable every time you run it, such as:

% /usr/local/jdk1.7.0/bin/javac MyClass.java

To find out if the path is properly set, execute:

This will print the version of the java tool, if it can find it. If the version is old or you get the error java: Command not found, then the path is not properly set.

To set the path permanently, set the path in your startup file.

For C shell ( csh ), edit the startup file (~/.cshrc ):

set path=(/usr/local/jdk1.7.0/bin $path)

For bash , edit the startup file ( ~/.bashrc ):

PATH=/usr/local/jdk1.7.0/bin:$PATH export PATH

For ksh , the startup file is named by the environment variable, ENV . To set the path:

PATH=/usr/local/jdk1.7.0/bin:$PATH export PATH

For sh , edit the profile file ( ~/.profile ):

PATH=/usr/local/jdk1.7.0/bin:$PATH export PATH

Then load the startup file and verify that the path is set by repeating the java command:

% source ~/.cshrc % java -version

Checking the CLASSPATH variable (All platforms)

The CLASSPATH variable is one way to tell applications, including the JDK tools, where to look for user classes. (Classes that are part of the JRE, JDK platform, and extensions should be defined through other means, such as the bootstrap class path or the extensions directory.)

The preferred way to specify the class path is by using the -cp command line switch. This allows the CLASSPATH to be set individually for each application without affecting other applications. Setting the CLASSPATH can be tricky and should be performed with care.

The default value of the class path is «.», meaning that only the current directory is searched. Specifying either the CLASSPATH variable or the -cp command line switch overrides this value.

To check whether CLASSPATH is set on Microsoft Windows NT/2000/XP, execute the following:

On Solaris or Linux, execute the following:

If CLASSPATH is not set you will get a CLASSPATH: Undefined variable error (Solaris or Linux) or simply %CLASSPATH% (Microsoft Windows NT/2000/XP).

To modify the CLASSPATH , use the same procedure you used for the PATH variable.

Class path wildcards allow you to include an entire directory of .jar files in the class path without explicitly naming them individually. For more information, including an explanation of class path wildcards, and a detailed description on how to clean up the CLASSPATH environment variable, see the Setting the Class Path technical note.

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Next page: Questions and Exercises: The Platform Environment

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How to set java path in windows 10

JAVA_HOME is environment variable which contains installation directory of Java development kit(JDK) or Java Runtime environment(JRE). This environment variable is setup at operating system level.

Why do you need JAVA_HOME?

JAVA_HOME environment variable points to directory where java is installed on your system, so many java based applications such as TOMCAT use JAVA_HOME environment variable to locate java executables.

How to set JAVA_HOME in Windows 10?

1. Locate JDK on your machine.
   • If you are using 64-bit java, then it will be in C:\Program Files\Java\
   • If you are using 32-bit java, then it will be in C:\Program Files (x86)\Java\
2. Open windows search, type environment and click on Edit the system environment variables .
3. In System properties dialog, go to Advanced tab and click on button Enviroment Variables .
4. In System variables, click NEW. button to add JAVA_HOME environment variable.
5. Provide variable name as JAVA_HOME and value as Java installation directory.

Set java path in window 10

Now let’s see how to set java in path environment variable in windows 10.

1. In System variable window, locate Path and click on Edit. .
2. Double click on the empty row and add %JAVA_HOME%\bin .
   Here, % symbol is used to locate JAVA_HOME environemt variable and \bin provides location for java.exe and h= javac.exe
3. Close the command prompt and launch again.
4. Check java version as below:

That’s all about How to set java path in windows 10.

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