Allow multiple options to be passed to compiler for options not supported by the compiler mojo

To be more precise, the Plexus Compiler and more specific, the Plexus CommandLine and Shell classes quotes each argument. Maybe also a suggestion for the Maven debug statement, which ommits these quotes. (It creates an own version of the commandline and output it) Show the real arguments given to javac.

I can try to create a patch for the

<compilerArguments>
<compilerArgument/>
<compilerArgument/>
</compilerArguments>

solution. Is this the best solution?

I am not the right person to comment what is the best solution, but another option to pass multiple arguments could be to just allow multiple compilerArgument without introducing compilerARguments, i.e.,
<configuration>
<compilerArgument>-foo</compilerArgument>
<compilerArgument>-bar</compilerArgument>
</compilerArgument>

I am hoping maven-compiler-plugin developers will make the right call.

Then you'll get something like this:

<configuration>
<compilerArguments>
<verbose />
<bootclasspath>$

\lib\rt.jar</bootclasspath>
</compilerArguments>
<compilerArgument>-proc:none</compilerArgument>
<compilerArgument>-implicit</compilerArgument>
</configuration>

In my opinion it is easier to read when there is a collection element around it.

a patch for the <compilerArgument> value not working propery. currently the entire value is used as a simple parameter, i think all that needs to happen is that the value needs to be splint on whitespace and each part added as a separate argument. this is what the patch does.

a more robust version may handle <cr> <lf> just in case.

if someone asks why not simply use <compilerArguments> tag, the reason is simple. currently the arguments tag works like this:

<compilerArguments><a>b</b><c/></compilerArguments>

becomes

javac a b c

but it is not uncommon to have parameters with an equal sign, such as -Acom.mycom.myprocessor.param=value, there types of params cannot be modelled in compilerArguments currently because <a=b/> is not valid xml. maybe support should be added for this usecase if values start with a "=" so that

<Acom.mycom.myprocessor.param>=value</..> will be properly handled as a single param instead of being split into two.

Is there any chance this patch could be incorporated? It seems to solve all the issues with a nice design, and has been around for 3 years. It also resolves the problems with MCOMPILER-135. I can't see any downside to it. It won't break any existing pom files.

here is updated MCOMPILER-62.patch for 2.3.2 version.
Also if you tired to wait, you can use my repo:

  <pluginRepositories>
    <pluginRepository>
      <id>am</id>
      <url>https://bitbucket.org/amelentev/mvnrepo/raw/tip/</url>
    </pluginRepository>
  </pluginRepositories>

And use <version>2.3.2-fix62</version> of maven-compiler-plugin

update patch to use StringUtils.split. support all whitespace chars.

"It won't break any existing pom files." - if you intentionally had <compilerArgument>-Akey=value with spaces</> that would be broken, if I understand the intent of the patch correctly.

there's a thread that is referring to this issue regarding annotation processors but there is a separate option for that since 2.2

<plugin>
  <artifactId>maven-compiler-plugin</artifactId>
  <configuration>
    <annotationProcessors>
      <annotationProcessor>
        org.hibernate.jpamodelgen.JPAMetaModelEntityProcessor
      </annotationProcessor>
    </annotationProcessors>
  </configuration>
</plugin>

I just noted that the documentation at
http://maven.apache.org/plugins/maven-compiler-plugin/examples/pass-compiler-arguments.html
is currently telling me that giving multiple arguments as the value of a <compilerArgument> element is valid, which is not true.

"For such arguments, the Compiler Plugin's compilerArguments will be used." Note the plural, which is not used in the following code snippet!

...
      <plugin>
        <groupId>org.apache.maven.plugins</groupId>
        <artifactId>maven-compiler-plugin</artifactId>
        <version>2.3.2</version>
        <configuration>
          <compilerArgument>-verbose -bootclasspath ${java.home}\lib\rt.jar</compilerArgument>
        </configuration>
      </plugin>