Reputation: 39

how to run a .jar 1.7 program with an older version java 1.6?

I have a code.jar running well in 1.7 version java, but when using another computer with linux with version 1.6 it is giving me an error, how can I run it in 1.6 version?

Upvotes: 3

Answers (5)

Radar6255

Reputation: 1

I have found a solution within Eclipse!

If you go to your project and right click to access the properties, there is a tab called Java Compiler. If you enable project specific properties and unclick the check box under JDK compliance, you can change the source compatibility and .class files compatibility to be 1.6.

This should fix your problem and the generated .jar file should work on both devices. I tested this by moving a file from 1.8 to 1.7 and testing on my Raspberry Pi that has OpenJDK 1.7 which worked great. I hope this helps.

Upvotes: 0

Andrew Thompson

Reputation: 168825

Use the cross-compilation options when invoking javac.

If only the -target option is specified as recommended in most other replies, the 1.7 SDK will issue a warning about -bootclasspath. That option requires an rt.jar of the target JRE version (note not JDK). It allows the compiler to check that the classes, methods and attributes of the code that reference core Java SE are actually present in the rt.jar. This is very important to ensure compatibility.

Upvotes: 3

BZapper

Reputation: 330

Build the project using Java 6 in eclipse, you will need to download Java 1.6 JRE, then have eclipse point to 1.6 JRE, see: http://www.cleartoolkit.com/dokuwiki/doku.php?id=clearwiki:20.cleardatabuilder:01.setup:01.prerequisites

Now right click on your project -> Properties, click Java Compiler, uncheck "enable project specific settings", click "Configure Workspace Settings" , and select 1.6 as your compiler compliance level.

Do "the thing" to export your project again, the new jar should work.

Hope this helps.

Upvotes: 1