setting JAVA_HOME in windows 7

Question

I am getting the following error when I try to run an ant buildfile in eclipse:

BUILD FAILED
C:\mypath\myapp\BuildWar.xml:16: Unable to find a javac compiler;
com.sun.tools.javac.Main is not on the classpath.
Perhaps JAVA_HOME does not point to the JDK.
It is currently set to "C:\Program Files\Java\jre7"  

I located the jdk at C:\\mypath\\Java\\jdk1.7.0_17\\bin\\javac.exe

I used the methods in this blog entry to create a system environmental variable in windows 7 called JAVA_HOME and mapped to C:\\mypath\\Java\\jdk1.7.0_17\\bin\\javac.exe . When the error persisted, I restarted the computer, tried again, and got the same error. I then changed the mapping of JAVA_HOME to C:\\mypath\\Java\\jdk1.7.0_17\\bin\\ and still got the same error.

Can anyone show me how to get past this error, so that I can run my ant build file in eclipse?

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EDIT:

I am getting the same exact error message again today when I try to run the ant buildfile, even though JAVA_HOME is set as per the answers below, and even though the path variable now includes %JAVA_HOME%\\bin . I have checked the values of these environmental variables in the windows control panel section for setting environmental variables, even though the eclipse console gives the above error message saying JAVA_HOME is set to a jre. Does anyone have any suggestions about how to fix this recurring problem?

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SECOND EDIT:

Changing the Java Home in eclipse fixed this problem. The eclipse Java Home is separate from the windows Java Home.

Answer 1

The JDK is the whole installation bundle, not just the javac executable.

Your JAVA_HOME environment variable should point to the top of your JDK installation, in your case - this means:

C:\\mypath\\Java\\jdk1.7.0_17\\

Answer 2

Set JAVA_HOME to C:\\mypath\\Java\\jdk1.7.0_17\\

Then in your path variable add %JAVA_HOME%\\bin

Answer 3

将JAVA_HOME为C:\\mypath\\Java\\jdk1.7.0_17\\并将C:\\mypath\\Java\\jdk1.7.0_17\\bin到PATH 。

Answer 4

1. Right click on My computer/ThisPC and click on properties option.
2. Click on Advanced system settings.
3. Click on Environment Variables.
4. Add JAVA_HOME (to java home path) Example: C:\\Program Files\\Java\\jdk1.8.0_111
5. Add PATH(Path to Java bin directory) Example: C:\\Program Files\\Java\\jdk1.8.0_111\\bin
6. Click on Apply and OK.

Visit this blog to see all steps with image: https://javatutorialdetails.blogspot.in/2017/10/how-java-program-work-step-by-step-in.html