You need SAP JVM switch tool for example if you want to switch it from IBM JVM to SAP JVM.
Since 1st of October, 2012, SAP JVM 4 is the only supported JDK on this release. See SAP Note 1708967 for details.
How to download SAP JVM Switch Tool?
Go to http://service.sap.com/instguides
On the left side bottom you would see SAP JVM Tool as in screenshot below.
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