Feature request: In debug mode, print full output of Java Compiler (including stdout)

[msridhar]

I first reported this issue on the Maven Compiler Plugin (https://issues.apache.org/jira/browse/MCOMPILER-407) and it was suggested that the fix needs to happen here first.

Certain Java annotation processors and compiler plugins like The Checker Framework can print useful diagnostics on stdout.  Currently, there is no way to see this output using the Maven Compiler Plugin, even when Maven is run with the -X option.  I suggest that when Maven is in debug mode, there should be a debug message printed with the full stdout of the Java compiler.  This should also work if the compiler is forked.

If someone points me at the relevant code, I am happy to try to submit a pull request for this change.

[rfscholte]

Start having a look at https://github.com/codehaus-plexus/plexus-compiler/blob/master/plexus-compilers/plexus-compiler-javac/src/main/java/org/codehaus/plexus/compiler/javac/JavacCompiler.java#L593-L633 (commandline) and https://github.com/codehaus-plexus/plexus-compiler/blob/master/plexus-compilers/plexus-compiler-javac/src/main/java/org/codehaus/plexus/compiler/javac/JavaxToolsCompiler.java#L133-L178 (javax tools)
Especially commandline is very tricky, because the output has changed over the years, but we need consistent output.

[urld]

There is a similiar issue #66 where errors are not printed when running javac in forked mode.

[msridhar]

Unfortunately I haven't had time to look at this, and may not for a while. If I get time to work on it I will comment here

[olamy]

duplicate with #39