How to find the OS bit type [duplicate]

Question

I want to know the OS type, means is it of 64bit os or 32bit os. But I am getting different response from 32bit/64bit executable which getting system properties about OS

I am getting details from system property. and I have 64bit machine and OS windows 8.1 X64

        "OS Architecture : " + System.getProperty("os.arch"));

        "OS Name : " + System.getProperty("os.name"));

        "OS Version : " + System.getProperty("os.version")

        "Data Model : " + System.getProperty("sun.arch.data.model"));

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While running 64bit Executable getting following response.

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OS Architecture : amd64

OS Name : Windows 8

OS Version : 6.2 amd64

Data Model : 64

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While running 32bit Executable getting following response.

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OS Architecture : x86

OS Name : Windows 8

OS Version : 6.2 x86

Data Model : 32

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How can I get OS actual bit type ?

Answer 1

System.getProperty("os.arch") will always return the bit type of the jre and not of the actual operating system.

Write jni code and calll IsWow64Process from winapi. Since you are using windows.

This boolean function tells you whether the process is running on 64-bit os.

Answer 2

This should help you

System.getProperty("os.arch");

will return "x86" when the architecture of JRE is 32 bit. We have to write native code to get the real architecture of the system using JNI.