ADDITIONAL SYSTEM INFORMATION :
Tried it with Ubuntu 18.04 64 bit on x86_64 with Java 13 EA 17 (OpenJDK Runtime Environment (build 13-ea+17))

A DESCRIPTION OF THE PROBLEM :
When darcula.jar from https://github.com/bulenkov/Darcula/raw/e208efb96f70e4be9dc362fbb46f6e181ef501dd/build/darcula.jar is on the classpath compilation will fail with an OOM.

Note: The offending jar has a few strange entries:
jar tf lib/darcula.jar | grep //
com//
com/bulenkov//
com/bulenkov/iconloader//
com/bulenkov/iconloader/util//
META-INF//

REGRESSION : Last worked in version 13

STEPS TO FOLLOW TO REPRODUCE THE PROBLEM :
# Create a trivial Java class
cat <<EOF > Simple.java
class Simple {}
EOF

# Download the offending jar
wget https://github.com/bulenkov/Darcula/raw/e208efb96f70e4be9dc362fbb46f6e181ef501dd/build/darcula.jar

# Try to compile the trivial Java class with the offending jar in the classpath
javac -classpath darcula.jar Simple.java

EXPECTED VERSUS ACTUAL BEHAVIOR :
EXPECTED -
A file named Simple.class, a return code of 0
ACTUAL -
OutOfMemory Exception from the compiler and return code of 3

---------- BEGIN SOURCE ----------
See "Steps to Reproduce"
---------- END SOURCE ----------

CUSTOMER SUBMITTED WORKAROUND :
unzip the darcula.jar and repack it with jar.

mkdir t
cd t
jar xf ../darcula.jar
jar cf ../darcula.jar
cd ..

FREQUENCY : always