<p>Is there a way to set/change the keyboard input language in Java (eg from English to German)? </p>

<p>Example Use Case: Script to be used for playback is recorded (typed in) on a German keyboard. The automated playback is done on a English keyboard...fails if keyboard is not set to German automatically before script is run.</p>

The keyboard input map is managed entirely by the operating system on every platform that I'm familiar with.  Java provides no APIs for manipulating this in a cross-platform manner.  I would investigate native APIs that you could manipulate via
JNA
, or even (if you're feeling dirty) shelling out to call some platform-specific command which does what you need.
You're not going to find a solution within the JDK standard lib.