Index: org.jboss.tools.ws.jaxrs.core/src/org/jboss/tools/ws/jaxrs/core/utils/JdtUtils.java
===================================================================
--- org.jboss.tools.ws.jaxrs.core/src/org/jboss/tools/ws/jaxrs/core/utils/JdtUtils.java	(revision 32289)
+++ org.jboss.tools.ws.jaxrs.core/src/org/jboss/tools/ws/jaxrs/core/utils/JdtUtils.java	(working copy)
@@ -252,12 +252,15 @@
 	 *            the progress monitor
 	 * @return compilationUnit the DOM CompilationUnit returned by the parse()
 	 *         method. This operation is expensive and should be performed only
-	 *         once for each type.
+	 *         once for each type. Returns null if the given member was null.
 	 * @throws JavaModelException
 	 *             in case of exception underneath...
 	 */
 	public static CompilationUnit parse(final IMember member, final IProgressMonitor progressMonitor)
 			throws JavaModelException {
+		if (member == null) {
+			return null;
+		}
 		IType type = null;
 		if (member.getElementType() == IMember.TYPE) {
 			type = (IType) member;
Index: org.jboss.tools.ws.jaxrs.ui/src/org/jboss/tools/ws/jaxrs/ui/contentassist/PathParamAnnotationValueCompletionProposalComputer.java
===================================================================
--- org.jboss.tools.ws.jaxrs.ui/src/org/jboss/tools/ws/jaxrs/ui/contentassist/PathParamAnnotationValueCompletionProposalComputer.java	(revision 32289)
+++ org.jboss.tools.ws.jaxrs.ui/src/org/jboss/tools/ws/jaxrs/ui/contentassist/PathParamAnnotationValueCompletionProposalComputer.java	(working copy)
@@ -21,6 +21,7 @@
 import org.eclipse.core.runtime.CoreException;
 import org.eclipse.core.runtime.IProgressMonitor;
 import org.eclipse.jdt.core.IJavaElement;
+import org.eclipse.jdt.core.IJavaProject;
 import org.eclipse.jdt.core.IMember;
 import org.eclipse.jdt.core.IMethod;
 import org.eclipse.jdt.core.IType;
@@ -40,6 +41,7 @@
 import org.eclipse.jface.text.contentassist.IContextInformation;
 import org.eclipse.jface.viewers.StyledString;
 import org.eclipse.swt.graphics.Image;
+import org.jboss.tools.ws.jaxrs.core.configuration.ProjectNatureUtils;
 import org.jboss.tools.ws.jaxrs.core.utils.JdtUtils;
 import org.jboss.tools.ws.jaxrs.ui.JBossJaxrsUIPlugin;
 import org.jboss.tools.ws.jaxrs.ui.internal.utils.Logger;
@@ -78,7 +80,16 @@
 			final IProgressMonitor monitor) {
 		JavaContentAssistInvocationContext javaContext = (JavaContentAssistInvocationContext) context;
 		try {
+
+			IJavaProject project = javaContext.getProject();
+			// skip if the JAX-RS Nature is not configured for this project
+			if (!ProjectNatureUtils.isProjectNatureInstalled(project.getProject(), ProjectNatureUtils.JAXRS_NATURE_ID)) {
+				return Collections.emptyList();
+			}
 			CompilationUnit compilationUnit = resolveContextualCompilationUnit(monitor, javaContext);
+			if (compilationUnit == null) {
+				return Collections.emptyList();
+			}
 			IJavaElement invocationElement = javaContext.getCompilationUnit().getElementAt(
 					context.getInvocationOffset());
 			if (invocationElement.getElementType() == IJavaElement.METHOD) {
@@ -222,6 +233,11 @@
 	 *             in case of underlying exception
 	 */
 	private IType getEnclosingType(final IJavaElement element) throws JavaModelException {
+		if (element == null) {
+			// no enclosing parent. For example, an annotation is set before the
+			// method itself was written.
+			return null;
+		}
 		switch (element.getElementType()) {
 		case IJavaElement.TYPE:
 			return (IType) element;