add defensive checks to fix excess logging

Java Model Exception: Java Model Status [<project> does not exist]
	at org.eclipse.jdt.internal.core.JavaElement.newNotPresentException(JavaElement.java:575)
	at org.eclipse.jdt.internal.core.JavaModelManager.getPerProjectInfoCheckExistence(JavaModelManager.java:2528)
	at org.eclipse.jdt.internal.core.JavaProject.getPerProjectInfo(JavaProject.java:2395)
	at org.eclipse.jdt.internal.core.JavaProject.getOutputLocation(JavaProject.java:2209)
	at org.eclipse.jdt.internal.launching.RuntimeClasspathEntry.getLocation(RuntimeClasspathEntry.java:517)
	at org.codehaus.jdt.groovy.internal.compiler.GroovyClassLoaderFactory.getAbsoluteLocation(GroovyClassLoaderFactory.java:207)
	at org.codehaus.jdt.groovy.internal.compiler.GroovyClassLoaderFactory.calculateClasspath(GroovyClassLoaderFactory.java:191)


Java Model Exception: Java Model Status [<project> does not exist]
	at org.eclipse.jdt.internal.core.JavaElement.newNotPresentException(JavaElement.java:575)
	at org.eclipse.jdt.internal.core.JavaModelManager.getPerProjectInfoCheckExistence(JavaModelManager.java:2528)
	at org.eclipse.jdt.internal.core.JavaProject.getPerProjectInfo(JavaProject.java:2395)
	at org.eclipse.jdt.internal.core.JavaProject.getRawClasspath(JavaProject.java:2424)
	at org.codehaus.groovy.eclipse.core.model.GroovyRuntime.findClasspathEntry(GroovyRuntime.java:156)
	at org.codehaus.groovy.eclipse.actions.AbstractClasspathContainerAction.selectionChanged(AbstractClasspathContainerAction.java:85)

Author: eric-milles

base/org.eclipse.jdt.groovy.core/src/org/codehaus/jdt/groovy/internal/compiler/GroovyClassLoaderFactory.java

@@ -48,6 +48,7 @@
 import org.eclipse.jdt.core.IClasspathEntry;
 import org.eclipse.jdt.core.IJavaProject;
 import org.eclipse.jdt.core.JavaCore;
+import org.eclipse.jdt.core.JavaModelException;
 import org.eclipse.jdt.groovy.core.util.ReflectionUtils;
 import org.eclipse.jdt.internal.compiler.Compiler;
 import org.eclipse.jdt.internal.compiler.batch.FileSystem;
@@ -204,21 +205,24 @@ private static IRuntimeClasspathEntry[] resolveRuntimeClasspathEntry(IRuntimeCla
     }
 
     private static String getAbsoluteLocation(IRuntimeClasspathEntry classpathEntry) {
-        String location = classpathEntry.getLocation();
+        if (classpathEntry.getType() == IRuntimeClasspathEntry.PROJECT) {
+            try {
+                // entry.getLocation() logs if project.getOutputLocation() throws, so test it first
+                ((IJavaProject) JavaCore.create(classpathEntry.getResource())).getOutputLocation();
+            } catch (NullPointerException | JavaModelException ignore) {
+                return classpathEntry.getResource().getLocation().toOSString();
+            }
+        }
 
-        Path path = new Path(location);
-        if (!path.toFile().exists()) {
+        String location = classpathEntry.getLocation();
+        if (!new File(location).exists()) {
+            IPath path = new Path(location);
             IProject project = findProject(path.segment(0));
             IResource resource = (path.segmentCount() == 1 ? project : project.getFile(path.removeFirstSegments(1)));
-
-            IPath rawLocation = resource.getRawLocation();
-            if (rawLocation != null) {
-                location = rawLocation.toOSString();
-            } else if (resource.getLocation() != null) {
+            if (resource.getLocation() != null) {
                 location = resource.getLocation().toOSString();
             }
         }
-
         return location;
     }
 

ide/org.codehaus.groovy.eclipse.core/src/org/codehaus/groovy/eclipse/core/model/GroovyRuntime.java

@@ -37,6 +37,7 @@
 import org.eclipse.jdt.core.JavaModelException;
 import org.eclipse.jdt.groovy.core.util.ArrayUtils;
 import org.eclipse.jdt.internal.core.ClasspathEntry;
+import org.eclipse.jdt.internal.core.JavaProject;
 import org.eclipse.jdt.launching.JavaRuntime;
 
 /**
@@ -153,7 +154,7 @@ public static void removeClasspathEntry(final IJavaProject javaProject, final IC
     }
 
     public static Optional<IClasspathEntry> findClasspathEntry(final IJavaProject javaProject, final Predicate<IClasspathEntry> p) throws JavaModelException {
-        return Arrays.stream(javaProject.getRawClasspath()).filter(p).findFirst();
+        return JavaProject.hasJavaNature(javaProject.getProject()) ? Arrays.stream(javaProject.getRawClasspath()).filter(p).findFirst() : Optional.empty();
     }
 
     //--------------------------------------------------------------------------

ide/org.codehaus.groovy.eclipse.ui/src/org/codehaus/groovy/eclipse/actions/AbstractClasspathContainerAction.java

@@ -67,9 +67,9 @@ public void selectionChanged(final IAction action, final ISelection selection) {
         if (selection instanceof IStructuredSelection) {
             Object selected = ((IStructuredSelection) selection).getFirstElement();
             if (selected instanceof IProject) {
-                IProject projSelected = (IProject) selected;
-                if (GroovyNature.hasGroovyNature(projSelected)) {
-                    targetProject = JavaCore.create(projSelected);
+                IProject selectedProject = (IProject) selected;
+                if (GroovyNature.hasGroovyNature(selectedProject)) {
+                    targetProject = JavaCore.create(selectedProject);
                 }
             } else if (selected instanceof IJavaProject) {
                 IJavaProject selectedProject = (IJavaProject) selected;