Troubleshoot build failures

Gradle-related

Compiler-related

type parameters of <T>T[] cannot be determined; no unique maximal instance exists for type

As occurred in http://build.springsource.org/browse/INT-TRUNK-3844:

/opt/springsource/tcServer/bamboo/bamboo-home/xml-data/build-dir/INT-TRUNK/checkout/spring-integration-file/src/main/java/org/springframework/integration/file/remote/session/CachingSessionFactory.java:124: type parameters of <F>F[] cannot be determined; no unique maximal instance exists for type variable F with upper bounds F,java.lang.Object
                        return this.targetSession.ls(path);
 
/opt/springsource/tcServer/bamboo/bamboo-home/xml-data/build-dir/INT-TRUNK/checkout/spring-integration-file/src/main/java/org/springframework/integration/file/remote/synchronizer/AbstractInboundFileSynchronizer.java:111: type parameters of <F>F[] cannot be determined; no unique maximal instance exists for type variable F with upper bounds F,java.lang.Object
                        F[] files = session.ls(this.remoteDirectory);
                                          ^
2 errors

FAILURE: Build failed with an exception.

* Where:
Empty build file

* What went wrong:
Execution failed for task ':spring-integration-file:compileJava'.
Cause: Compile failed; see the compiler error output for details.

* Try:
Run with -s or -d option to get more details. Run with -S option to get the full (very verbose) stacktrace.

This error is due to a difference between the Eclipse and Sun compilers. See http://stackoverflow.com/questions/314572/bug-in-eclipse-compiler-or-in-javac for details, as well as the commit that resolved this issue in in Spring Integration.