1 files changed, 72 insertions, 0 deletions

diff --git a/subprojects/viatra-runtime/src/main/java/tools/refinery/viatra/runtime/registry/IRegistryView.java b/subprojects/viatra-runtime/src/main/java/tools/refinery/viatra/runtime/registry/IRegistryView.java
new file mode 100644
index 00000000..acf49b76
--- /dev/null
+++ b/subprojects/viatra-runtime/src/main/java/tools/refinery/viatra/runtime/registry/IRegistryView.java
@@ -0,0 +1,72 @@
+/*******************************************************************************
+ * Copyright (c) 2010-2016, Abel Hegedus, IncQuery Labs Ltd.
+ * This program and the accompanying materials are made available under the
+ * terms of the Eclipse Public License v. 2.0 which is available at
+ * http://www.eclipse.org/legal/epl-v20.html.
+ * 
+ * SPDX-License-Identifier: EPL-2.0
+ *******************************************************************************/
+package tools.refinery.viatra.runtime.registry;
+
+import java.util.Set;
+
+/**
+ * The registry view is the primary interface for users to interact with the query specifications in an
+ * {@link IQuerySpecificationRegistry}. Views are created using the createView methods of registry and their content is
+ * also dynamically updated by the registry.
+ * 
+ * The view contains a set of {@link IQuerySpecificationRegistryEntry} objects that can be used to access the query
+ * specifications themselves through the get() method.
+ * 
+ * Users can check the contents of the view and add listeners to get notifications on view changes (added or removed
+ * entries).
+ * 
+ * @author Abel Hegedus
+ * @since 1.3
+ *
+ */
+public interface IRegistryView extends IQuerySpecificationRegistryChangeListener {
+
+    /**
+     * @return an immutable copy of all entries found in the view
+     */
+    Iterable<IQuerySpecificationRegistryEntry> getEntries();
+
+    /**
+     * @return the set of FQNs for the query specifications in the view
+     */
+    Set<String> getQuerySpecificationFQNs();
+
+    /**
+     * @param fullyQualifiedName
+     *            that is looked up in the view
+     * @return true if the view contains an entry with given FQN, false otherwise
+     */
+    boolean hasQuerySpecificationFQN(String fullyQualifiedName);
+
+    /**
+     * @param fullyQualifiedName
+     *            of the entries that are requested
+     * @return the possible empty set of entries with the given FQN
+     */
+    Set<IQuerySpecificationRegistryEntry> getEntries(String fullyQualifiedName);
+
+    /**
+     * Adds a listener to the view that will be notified when an entry is added to or removed from the view.
+     * 
+     * @param listener that is added
+     */
+    void addViewListener(IQuerySpecificationRegistryChangeListener listener);
+
+    /**
+     * Removes a listener that was previously added to the view.
+     * 
+     * @param listener that is removed
+     */
+    void removeViewListener(IQuerySpecificationRegistryChangeListener listener);
+
+    /**
+     * @return the registry underlying the view
+     */
+    IQuerySpecificationRegistry getRegistry();
+}