1 files changed, 177 insertions, 0 deletions

diff --git a/subprojects/viatra-runtime/src/main/java/tools/refinery/viatra/runtime/registry/impl/QuerySpecificationRegistryImpl.java b/subprojects/viatra-runtime/src/main/java/tools/refinery/viatra/runtime/registry/impl/QuerySpecificationRegistryImpl.java
new file mode 100644
index 00000000..63306e93
--- /dev/null
+++ b/subprojects/viatra-runtime/src/main/java/tools/refinery/viatra/runtime/registry/impl/QuerySpecificationRegistryImpl.java
@@ -0,0 +1,177 @@
+/*******************************************************************************
+ * 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.impl;
+
+import static tools.refinery.viatra.runtime.matchers.util.Preconditions.checkArgument;
+
+import java.util.Map;
+
+import org.apache.log4j.Logger;
+import tools.refinery.viatra.runtime.extensibility.IQuerySpecificationProvider;
+import tools.refinery.viatra.runtime.registry.IConnectorListener;
+import tools.refinery.viatra.runtime.registry.IDefaultRegistryView;
+import tools.refinery.viatra.runtime.registry.IQuerySpecificationRegistry;
+import tools.refinery.viatra.runtime.registry.IRegistryView;
+import tools.refinery.viatra.runtime.registry.IRegistryViewFactory;
+import tools.refinery.viatra.runtime.registry.IRegistryViewFilter;
+import tools.refinery.viatra.runtime.registry.IQuerySpecificationRegistryChangeListener;
+import tools.refinery.viatra.runtime.registry.IRegistrySourceConnector;
+import tools.refinery.viatra.runtime.registry.data.QuerySpecificationStore;
+import tools.refinery.viatra.runtime.registry.data.RegistryEntryImpl;
+import tools.refinery.viatra.runtime.registry.data.RegistrySourceImpl;
+import tools.refinery.viatra.runtime.util.ViatraQueryLoggingUtil;
+
+/**
+ * This is the default implementation of the {@link IQuerySpecificationRegistry} interface.
+ * It uses a {@link QuerySpecificationStore} to keep track of sources and entries.
+ * It uses a {@link RegistryChangeMultiplexer} to update all views and a single {@link IConnectorListener}
+ * to subscribe to sources added to the registry.
+ * 
+ * @author Abel Hegedus
+ *
+ */
+public class QuerySpecificationRegistryImpl implements IQuerySpecificationRegistry {
+
+    private static final String CONNECTOR_NULL_MSG = "Connector cannot be null";
+    private final QuerySpecificationStore querySpecificationStore;
+    private final IConnectorListener connectorListener;
+    private final RegistryChangeMultiplexer multiplexer;
+    private final Logger logger;
+    private IDefaultRegistryView defaultView = null;
+    
+    /**
+     * Creates a new instance of the registry
+     */
+    public QuerySpecificationRegistryImpl() {
+        this.querySpecificationStore = new QuerySpecificationStore();
+        this.connectorListener = new RegistryUpdaterConnectorListener();
+        this.multiplexer = new RegistryChangeMultiplexer();
+        this.logger = ViatraQueryLoggingUtil.getLogger(IQuerySpecificationRegistry.class);
+    }
+    
+    @Override
+    public boolean addSource(IRegistrySourceConnector connector) {
+        checkArgument(connector != null, CONNECTOR_NULL_MSG);
+        String identifier = connector.getIdentifier();
+        Map<String, RegistrySourceImpl> sources = querySpecificationStore.getSources();
+        if(sources.containsKey(identifier)){
+            return false;
+        }
+        RegistrySourceImpl source = new RegistrySourceImpl(identifier, querySpecificationStore, connector.includeSpecificationsInDefaultViews());
+        sources.put(identifier, source);
+        connector.addListener(connectorListener);
+        logger.debug("Source added: " + source.getIdentifier());
+        return true;
+    }
+    
+    @Override
+    public boolean removeSource(IRegistrySourceConnector connector) {
+        checkArgument(connector != null, CONNECTOR_NULL_MSG);
+        String identifier = connector.getIdentifier();
+        Map<String, RegistrySourceImpl> sources = querySpecificationStore.getSources();
+        if(!sources.containsKey(identifier)){
+            return false;
+        }
+        connector.removeListener(connectorListener);
+        RegistrySourceImpl source = sources.remove(identifier);
+        for (RegistryEntryImpl entry : source.getFqnToEntryMap().values()) {
+            multiplexer.entryRemoved(entry);
+        }
+        logger.debug("Source removed: " + source.getIdentifier());
+        return true;
+    }
+    
+    /**
+     * @return the internal store of the registry
+     */
+    protected QuerySpecificationStore getStore() {
+        return querySpecificationStore;
+    }
+
+    @Override
+    public IRegistryView createView() {
+        return createGlobalView();
+    }
+
+    private GlobalRegistryView createGlobalView() {
+        GlobalRegistryView registryView = new GlobalRegistryView(this);
+        initializeChangeListener(registryView);
+        return registryView;
+    }
+
+    protected void initializeChangeListener(IQuerySpecificationRegistryChangeListener listener) {
+        // send existing entries to aspect
+        for (RegistrySourceImpl source : querySpecificationStore.getSources().values()) {
+            Map<String, RegistryEntryImpl> entryMap = source.getFqnToEntryMap();
+            for (RegistryEntryImpl entry : entryMap.values()) {
+                listener.entryAdded(entry);
+            }
+        }
+        multiplexer.addListener(listener);
+    }
+
+    @Override
+    public IRegistryView createView(IRegistryViewFilter filter) {
+        checkArgument(filter != null, "Filter cannot be null");
+        FilteringRegistryView registryView = new FilteringRegistryView(this, filter, false);
+        initializeChangeListener(registryView);
+        return registryView;
+    }
+
+    /**
+     * Internal connector listener implementation for updating internal store and propagating changes to views.
+     * 
+     * @author Abel Hegedus
+     *
+     */
+    private final class RegistryUpdaterConnectorListener implements IConnectorListener {
+        @Override
+        public void querySpecificationAdded(IRegistrySourceConnector connector, IQuerySpecificationProvider specification) {
+            String identifier = connector.getIdentifier();
+            RegistrySourceImpl source = querySpecificationStore.getSources().get(identifier);
+            String fullyQualifiedName = specification.getFullyQualifiedName();
+            RegistryEntryImpl registryEntry = new RegistryEntryImpl(source, specification);
+            RegistryEntryImpl oldEntry = source.getFqnToEntryMap().put(fullyQualifiedName, registryEntry);
+            if(oldEntry != null) {
+                logger.warn(String.format("Specification added with existing FQN %s in source %s", fullyQualifiedName, identifier));
+                multiplexer.entryRemoved(oldEntry);
+            }
+            multiplexer.entryAdded(registryEntry);
+            
+        }
+
+        @Override
+        public void querySpecificationRemoved(IRegistrySourceConnector connector, IQuerySpecificationProvider specification) {
+            String identifier = connector.getIdentifier();
+            RegistrySourceImpl source = querySpecificationStore.getSources().get(identifier);
+            String fullyQualifiedName = specification.getFullyQualifiedName();
+            RegistryEntryImpl registryEntry = source.getFqnToEntryMap().remove(fullyQualifiedName);
+            if(registryEntry != null) {
+                multiplexer.entryRemoved(registryEntry);
+            }
+        }
+    }
+
+    @Override
+    public IDefaultRegistryView getDefaultView() {
+        if(this.defaultView == null){
+            this.defaultView = createGlobalView();
+        }
+        return this.defaultView;
+    }
+
+    @Override
+    public IRegistryView createView(IRegistryViewFactory factory) {
+        IRegistryView registryView = factory.createView(this);
+        initializeChangeListener(registryView);
+        return registryView;
+    }
+    
+    
+}