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I installed java from Oracle website (here.) the last one Windows x64, but when I try to set the path there is no JDK folder inside the installation folder. There is jre folder there but it doesn't show any version number. How can I fix this issue, because I need to run jruby on Windows for that I want Java as well.

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migrated from Sep 23 '11 at 20:07

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The JRE is the runtime, are yousure you need the SDK for jRuby to run ? – orn Sep 23 '11 at 2:46
Yes I need JDK. – jens Sep 23 '11 at 2:55

The download path tell you the jdk version is Java6 update 27, you can run java -version to verify the version.

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Thanks..I run the command java-version i got 1.7.0 but in the installed folder there is not jdk folder all I have is bin db demo include jre(no version number) lib sample and some files. My question is how could I set the path in windows as there is not jdk folder – jens Sep 23 '11 at 2:52
There is no 'jdk' folder in jdk. Just set path to 'bin' folder if you want to run javac from command line. – Zhongshu Sep 23 '11 at 2:57
I put like this JAVA_HOME C:\development\java\bin Then I got a message Can not locate java installation specified by JAVA_HOME C:\development\java\bin\java.exe – jens Sep 23 '11 at 3:09
I am afraid executing java -version does not tell you if you have a jdk. – rht Sep 23 '11 at 3:52
You should set JAVA_HOME to jdk root path. – Zhongshu Sep 23 '11 at 3:57

I am afraid executing java -version will not tell you if you have a jdk. By default JDK is installed under Program FIles like in my case it is here C:\Program Files (x86)\Java\jdk1.6.0_22

Check out the similar location on your box and see if it has javac . If you find javac under bin then, you have the jdk.

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Thanks for the reply. Actually I changed the location of Java installation to something different C:\development\Java\bin, under this bin file there is a javac.exe file. Any way I will try your method as well. Thanks – jens Sep 23 '11 at 3:57
Thanks...I installed to programfile location and it works..Thanks.. – jens Sep 23 '11 at 4:01
There shouldn't be a need to re-install the JDK. If you had it at some other location then, you just need to set JAVA_HOME=c:\some_other_location and it will work as @zhongshu has pointed out. – rht Sep 23 '11 at 13:58

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