Fixed some bugs that may cause solver incorrectness.

2 jobs for master in 9 minutes and 33 seconds (queued for 4 seconds)
Name Stage Failure
failed
mybuild Build There is an unknown failure, please try again
	at org.sonarsource.scanner.api.internal.ServerConnection.downloadString(ServerConnection.java:98)
at org.sonarsource.scanner.api.internal.Jars.getBootstrapIndex(Jars.java:96)
... 34 more
5917 [ERROR]
5917 [ERROR] Re-run Maven using the -X switch to enable full debug logging.
5918 [ERROR]
5918 [ERROR] For more information about the errors and possible solutions, please read the following articles:
5918 [ERROR] [Help 1] http://cwiki.apache.org/confluence/display/MAVEN/MojoExecutionException
ERROR: Job failed: exit code 1