Java Target Integration

[arthurscchan]

Integrate support for Java fuzzing.

The tentative steps:

1. Add a set of java test cases with different classes, packages and library usage to demonstrate basic support for java projects.
2. Add static call graph generator tools for the post-processing. Possible choice is SOOT
   https://soot-oss.github.io/soot/
3. Add additional logic to process data from java-callgraph.
4. Alteration of fuzz-introspector code to accept java call-graph structure with cross libraries and classes support
5. Consider coverage report generator for Java code project, Possible choice are modified version of JCov or JaCoco https://github.com/jacoco/jacoco / https://github.com/openjdk/jcov
6. Demonstrate full end-to-end coverage report and static call graph generation features
7. Alteration of result from sub-modules to ensure if fit the needed input data structure for fuzz-introspector's further processing.

[arthurscchan]

PR #537 aim to create base java testcases for step 1.

[arthurscchan]

PR #539 aim to manage testcases and add build script for the test cases. It also import necessary jar library for the built and calling to java-callgraph.
Handling step 1 and 2 shown above.

[DavidKorczynski]

In parallel with the callgraph we should look for the other program attributes fuzz introspector needs, such as information about:

• instructions in a function
• branches
• basic blocks
• source code lines
  etc.

It probably manifests a bit different in comparison to C/C++ so we may need to look for alternative and similar data points.

[arthurscchan]

JVM coverage report integration has been done and it has been bridged with OSS-FUZZ. Next step will be testing and bug fixing. Some minor bug fixing will be solved in Issue #629.

[DavidKorczynski]

Well done getting this through @arthurscchan -- super excited to see this.

[AdamKorcz]

Awesome stuff! @arthurscchan