Description of problem:

This code fails with NPE on Fedora with java-11-openjdk:

try {
  SimpleDateFormat simpleDateFormat = new SimpleDateFormat("EEE MMM dd HH:mm:ss Z yyyy");
  simpleDateFormat.parse("Tue Feb 2 23:20:02 ABC 2016");
} catch (ParseException e) {
  e.printStackTrace();
}

OpenJDK package from Fedora behaves differently than OpenJDK downloaded from https://openjdk.java.net

Difference is: Fedora has its own tzdb.dat (timezone database) provided by tzdata-java package. If you call DateFormatSymbols.getInstance().getZoneStrings() you get an array with 599 items. The same call with OpenJDK from https://openjdk.java.net returns 598 items. Additional item on Fedora is "America/Nuuk", which is an existing timezone. Problem with that timezone is, it does not has short and long names. In result array, short and long name is null. Method SimpleDateFormat.matchZoneString() does not expect null for short and long name, there is no null-check. Because of that, NPE is the result of the call. According to JDK documentation, NPE should not happen in SimpleDateFormat.parse()

Version-Release number of selected component (if applicable):
java-11-openjdk-11.0.6.10-0.fc32.x86_64
java-latest-openjdk-14.0.1.7-2.rolling.fc32.x86_64

How reproducible:
Compile and run this code:

try {
  SimpleDateFormat simpleDateFormat = new SimpleDateFormat("EEE MMM dd HH:mm:ss Z yyyy");
  simpleDateFormat.parse("Tue Feb 2 23:20:02 ABC 2016");
} catch (ParseException e) {
  e.printStackTrace();
}

Steps to Reproduce:
1. Compile
2. Run
3. NPE is result

Actual results:
NPE

Expected results:
No NPE

Additional info:
OpenJDK tarball has its own tzdb.dat. With that file everything works as expected. RHEL 7 and RHEL 8 have the same problem.