build.tools.dtdbuilder.DTDBuilder.java failed detecting missing path of dtd_home

A DESCRIPTION OF THE PROBLEM :
When none dtd_home property is set the dtd_home string value is not null.



EXPECTED VERSUS ACTUAL BEHAVIOR :
EXPECTED -
Quit with the message : Must set property 'dtd_home'
ACTUAL -
Exception in thread "main" java.lang.NullPointerException
at java.base/java.io.FileInputStream.<init>(FileInputStream.java:145)
at java.base/java.io.FileInputStream.<init>(FileInputStream.java:108)
at dtdbuilder.DTDBuilder.main(DTDBuilder.java:263)
/home/scientificware2016/NetBeansProjects/android/DTDBuilder/nbproject/build-impl.xml:1330: The following error occurred while executing this line:
/home/scientificware2016/NetBeansProjects/android/DTDBuilder/nbproject/build-impl.xml:936: Java returned: 1
BUILD FAILED (total time: 0 seconds)

CUSTOMER SUBMITTED WORKAROUND :
https://github.com/openjdk/jdk/pull/3626

FREQUENCY : always