java frontend does not allow parallel execution

[DavidKorczynski]

The following lines run the fuzz introspector frontend for java:

fuzz-introspector/frontends/java/run.sh

Lines 131 to 135 in 07dcb18

	for CLASS in $(echo $ENTRYCLASS | tr ":" "\n")
	do
	echo $CLASS
	java -Xmx6144M -cp "target/ossf.fuzz.introspector.soot-1.0.jar" ossf.fuzz.introspector.soot.CallGraphGenerator $JARFILE $CLASS $ENTRYMETHOD "$PACKAGEPREFIX" "$EXCLUDEMETHOD" "$SRCDIRECTORY" $AUTOFUZZ "$INCLUDEPREFIX===$EXCLUDEPREFIX===$SINKMETHOD"
	done

In the case where a project has a lot of fuzzers it can take a bit of time to process all of the fuzzers, and it would be great to have some form of parallel execution in the above loop.

We could use a similar approach as the coverage runner in oss-fuzz:

https://github.com/google/oss-fuzz/blob/d253560ffd5611b136b81b183a72715f22a990a8/infra/base-images/base-runner/coverage#L367-L372

[DavidKorczynski]

@arthurscchan could you take a look at this?

[DavidKorczynski]

As pointed out by @arthurscchan we should update things here https://github.com/ossf/fuzz-introspector/blob/main/frontends/java/oss-fuzz-main.py#L109

[DavidKorczynski]

Am closing this. SOOT has some issues with having multiple processes analysing a .jar file it seems. Performance gains were found elsewhere.