Fixes #94: Changing a project's PMD configuration no longer prompts for build

Author: adangel

ReleaseNotes.md

@@ -13,6 +13,8 @@ This is a bugfix release.
 
 ### Fixed Issues
 
+*   [#94](https://github.com/pmd/pmd-eclipse-plugin/issues/94): Changing a project's PMD configuration no longer prompts for build
+
 ## 07-March-2019: 4.1.0.v20190307-2036
 
 This is a minor release.

net.sourceforge.pmd.eclipse.plugin/src/main/java/net/sourceforge/pmd/eclipse/ui/properties/PMDPropertyPageController.java

@@ -142,6 +142,7 @@ public boolean performOk() {
             cmd.setViolationsAsErrors(propertyPageBean.violationsAsErrors());
             cmd.setUserInitiated(true);
             cmd.performExecute();
+            cmd.join(); // need to wait, otherwise cmd.isNeedRebuild() is not updated
 
             // If rebuild is needed, then rebuild the project
             LOG.debug("Updating command terminated, checking whether the project need to be rebuilt");