Move find references filter (part 1).

Adds InferredModelReferenceFilter to ide plugin as first part of moving
it from ui plugin.

com.avaloq.tools.ddk.xtext.ide/META-INF/MANIFEST.MF

@@ -10,6 +10,7 @@ Require-Bundle: org.eclipse.lsp4j,
 Bundle-RequiredExecutionEnvironment: JavaSE-17
 Bundle-ActivationPolicy: lazy
 Export-Package: com.avaloq.tools.ddk.xtext.ide.contentAssist,
- com.avaloq.tools.ddk.xtext.ide.formatting
+ com.avaloq.tools.ddk.xtext.ide.formatting,
+ com.avaloq.tools.ddk.xtext.ide.findrefs
 Import-Package: org.apache.log4j
 Automatic-Module-Name: com.avaloq.tools.ddk.xtext.ide

com.avaloq.tools.ddk.xtext.ide/src/com/avaloq/tools/ddk/xtext/ide/findrefs/InferredModelReferenceFilter.java

@@ -0,0 +1,54 @@
+/*******************************************************************************
+ * Copyright (c) 2016 Avaloq Group AG 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
+ * http://www.eclipse.org/legal/epl-v10.html
+ *
+ * Contributors:
+ * Avaloq Group AG - initial API and implementation
+ *******************************************************************************/
+package com.avaloq.tools.ddk.xtext.ide.findrefs;
+
+import org.eclipse.emf.common.util.URI;
+import org.eclipse.xtext.resource.IReferenceDescription;
+
+import com.google.common.base.Predicate;
+
+
+/**
+ * A filter for filtering out inferred model elements.
+ */
+public class InferredModelReferenceFilter implements Predicate<IReferenceDescription> {
+
+ /**
+ * {@inheritDoc}
+ *
+ * @return true if {@code input} is not an inferred model element.
+ */
+ @Override
+ public boolean apply(final IReferenceDescription input) {
+ return !isInferredModelElement(input.getSourceEObjectUri());
+ }
+
+ /**
+ * Checks a model element's URI to determine if it is an inferred model element.
+ *
+ * @param elementURI
+ * the URI to check
+ * @return true if {@code elementURI} is the URI of an inferred model element; false otherwise.
+ */
+ protected boolean isInferredModelElement(final URI elementURI) {
+ String fragment = elementURI.fragment();
+ if (fragment.length() > 1) {
+ char firstCharacter = fragment.charAt(1);
+ // Normally, URI fragments of non-inferred elements look like: /0/x/y/z/
+ // However, there is an exception to this rule, which is WFD that uses a custom FragmentProvider
+ // There, EMF feature names are used and fragments look in the following way: /WfdSource/Wfd/x/y/z
+ // Hence, the first check is needed to handle this case
+ return Character.isDigit(firstCharacter) && firstCharacter != '0';
+ }
+ return false;
+ }
+
+}