Fixed bug 468305: [common navigator] 'Non-Java projects' and 'Non-Java elements'  filters hide Java projects in Project Explorer
diff --git a/org.eclipse.jdt.ui/ui/org/eclipse/jdt/internal/ui/filters/NonJavaElementFilter.java b/org.eclipse.jdt.ui/ui/org/eclipse/jdt/internal/ui/filters/NonJavaElementFilter.java
index 385a826..bb429e3 100644
--- a/org.eclipse.jdt.ui/ui/org/eclipse/jdt/internal/ui/filters/NonJavaElementFilter.java
+++ b/org.eclipse.jdt.ui/ui/org/eclipse/jdt/internal/ui/filters/NonJavaElementFilter.java
@@ -1,5 +1,5 @@
 /*******************************************************************************
- * Copyright (c) 2000, 2011 IBM Corporation and others.
+ * Copyright (c) 2000, 2015 IBM Corporation and others.
  * All rights reserved. This program and the accompanying materials
  * are made available under the terms of the Eclipse Public License v1.0
  * which accompanies this distribution, and is available at
@@ -10,6 +10,8 @@
  *******************************************************************************/
 package org.eclipse.jdt.internal.ui.filters;
 
+import org.eclipse.core.runtime.CoreException;
+
 import org.eclipse.core.resources.IProject;
 import org.eclipse.core.resources.IResource;
 import org.eclipse.core.resources.IStorage;
@@ -18,6 +20,7 @@
 import org.eclipse.jface.viewers.ViewerFilter;
 
 import org.eclipse.jdt.core.IJavaElement;
+import org.eclipse.jdt.core.JavaCore;
 
 
 /**
@@ -33,6 +36,15 @@
 		if (element instanceof IJavaElement)
 			return true;
 
+		if (element instanceof IProject) {
+			IProject project= (IProject) element;
+			try {
+				return project.hasNature(JavaCore.NATURE_ID);
+			} catch (CoreException e) {
+				return true;
+			}
+		}
+
 		if (element instanceof IResource) {
 			IProject project= ((IResource)element).getProject();
 			return project == null || !project.isOpen();
diff --git a/org.eclipse.jdt.ui/ui/org/eclipse/jdt/internal/ui/filters/NonJavaProjectsFilter.java b/org.eclipse.jdt.ui/ui/org/eclipse/jdt/internal/ui/filters/NonJavaProjectsFilter.java
index 707e2fc..1aa46b2 100644
--- a/org.eclipse.jdt.ui/ui/org/eclipse/jdt/internal/ui/filters/NonJavaProjectsFilter.java
+++ b/org.eclipse.jdt.ui/ui/org/eclipse/jdt/internal/ui/filters/NonJavaProjectsFilter.java
@@ -1,5 +1,5 @@
 /*******************************************************************************
- * Copyright (c) 2000, 2011 IBM Corporation and others.
+ * Copyright (c) 2000, 2015 IBM Corporation and others.
  * All rights reserved. This program and the accompanying materials
  * are made available under the terms of the Eclipse Public License v1.0
  * which accompanies this distribution, and is available at
@@ -11,12 +11,15 @@
 package org.eclipse.jdt.internal.ui.filters;
 
 
+import org.eclipse.core.runtime.CoreException;
+
 import org.eclipse.core.resources.IProject;
 
 import org.eclipse.jface.viewers.Viewer;
 import org.eclipse.jface.viewers.ViewerFilter;
 
 import org.eclipse.jdt.core.IJavaProject;
+import org.eclipse.jdt.core.JavaCore;
 
 /**
  * Filters non-java projects
@@ -30,8 +33,15 @@
 	public boolean select(Viewer viewer, Object parent, Object element) {
 		if (element instanceof IJavaProject)
 			return true;
-		else if (element instanceof IProject)
-			return !((IProject)element).isOpen();
+
+		if (element instanceof IProject) {
+			IProject project= (IProject) element;
+			try {
+				return project.hasNature(JavaCore.NATURE_ID);
+			} catch (CoreException e) {
+				return true;
+			}
+		}
 
 		return true;
 	}