If you discover an issue with the JDK, please start by searching the Bug Database to find out if that issue has been reported and fixed already. Once you confirm that the issue you discovered is new, please report it here.
In your report, please include all relevant and detailed information necessary to reproduce the issue. As a simple example, a submission should include a test case demonstrating the issue to make it easier to reproduce. For more information about reporting issues, please see the Java SE Troubleshooting Guide.
Please note that fixes for bug reports are not guaranteed through this channel. For bugs that require immediate and personal attention, Oracle offers Java SE Subscription. Support customers should report bugs through My Oracle Support.
If you have a suggestion for a small change to an existing API or the way in which the JDK behaves, please propose it here.
Please note that the Bug Database is not the venue to propose large changes to the JDK. Ongoing feature development is carried out in OpenJDK; corresponding enhancements to The Java Language Specification and The JVM Specification are managed through the Java Community Process.
If you are interested in contributing to OpenJDK, please start by reviewing the contributor guidelines.
Refer to the Bug Submission FAQ's to answer questions you have related to the Bug Database and the Bug Submission Process.
Report issues or provide feedback on bugs.java.com or bugreport.java.com here.