Summary

Making the support for "JLine" based Console as "opt-in"

Problem

The enhancement introduced in JDK-8295803 uses the JLine library (jdk.internal.le module) as the java.io.Console implementation by default. This resulted in the performance regression as reported in JDK-8299137.

Solution

Making the support for JLine optional. By default, JDK 20 will work like all previous releases. The JDK internal (and undocumented) system property jdk.console can be used to select the JLine implementation with -Djdk.console=jdk.internal.le.

A future JDK release will re-visit this once the performance issue in JLine initialization is resolved.

Specification

N/A. This is a behavioral change only.