tmf: Add TmfTraceAdapterManager

This adapter manager can handle adapters that are specific to a
particular trace type id, to provide specific adapters even if the trace
instance is of the same class.

Unlike AdapterManager, this manager will return a list of all matching
adapters that adapt the given trace.

Change-Id: I4c8d6e6d725cf80a2e9ab865ea3217ae05f8cc73
Signed-off-by: Patrick Tasse <patrick.tasse@gmail.com>
Reviewed-on: https://git.eclipse.org/r/58863
Reviewed-by: Hudson CI

diff --git a/tmf/org.eclipse.tracecompass.tmf.core/src/org/eclipse/tracecompass/tmf/core/trace/TmfTraceAdapterManager.java b/tmf/org.eclipse.tracecompass.tmf.core/src/org/eclipse/tracecompass/tmf/core/trace/TmfTraceAdapterManager.java
new file mode 100644 (file)
index 0000000..7baceda
--- /dev/null
+++ b/tmf/org.eclipse.tracecompass.tmf.core/src/org/eclipse/tracecompass/tmf/core/trace/TmfTraceAdapterManager.java
@@ -0,0 +1,116 @@
+/*******************************************************************************
+ * Copyright (c) 2015 Ericsson
+ *
+ * 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:
+ *   Patrick Tasse - Initial API and implementation
+ *******************************************************************************/
+
+package org.eclipse.tracecompass.tmf.core.trace;
+
+import java.util.ArrayList;
+import java.util.Collection;
+import java.util.List;
+import java.util.Map.Entry;
+
+import org.eclipse.core.runtime.IAdapterFactory;
+
+import com.google.common.collect.HashMultimap;
+import com.google.common.collect.Multimap;
+
+/**
+ * This class manages adapter factories for traces. An adapter can be specific
+ * to a given trace type id, or to traces of a given trace class.
+ *
+ * @since 2.0
+ */
+public class TmfTraceAdapterManager {
+
+    private static Multimap<String, IAdapterFactory> fFactoriesById = HashMultimap.create();
+    private static Multimap<Class<? extends ITmfTrace>, IAdapterFactory> fFactoriesByClass = HashMultimap.create();
+
+    /**
+     * Registers the given adapter factory as extending traces with the given
+     * trace type id.
+     * </p>
+     *
+     * @param factory
+     *            the adapter factory
+     * @param traceTypeId
+     *            the trace type id of traces being extended
+     */
+    public static void registerFactory(IAdapterFactory factory, String traceTypeId) {
+        fFactoriesById.put(traceTypeId, factory);
+    }
+
+    /**
+     * Registers the given adapter factory as extending traces of the given
+     * class.
+     * <p>
+     * If the trace class being extended is a class, the given factory's
+     * adapters are available on instances of that class and any of its
+     * subclasses. If it is an interface, the adapters are available to all
+     * classes that directly or indirectly implement that interface.
+     * </p>
+     *
+     * @param factory
+     *            the adapter factory
+     * @param traceClass
+     *            the class of traces being extended
+     */
+    public static void registerFactory(IAdapterFactory factory, Class<? extends ITmfTrace> traceClass) {
+        fFactoriesByClass.put(traceClass, factory);
+    }
+
+    /**
+     * Removes the given adapter factory completely from the list of registered
+     * factories.
+     *
+     * @param factory
+     *            the adapter factory to remove
+     * @see #registerFactory(IAdapterFactory, Class)
+     * @see #registerFactory(IAdapterFactory, String)
+     */
+    public static void unregisterFactory(IAdapterFactory factory) {
+        fFactoriesById.values().remove(factory);
+        fFactoriesByClass.values().remove(factory);
+    }
+
+    /**
+     * Returns a list of object which are instances of the given class
+     * associated with the given trace. Returns an empty list if no such object
+     * can be found.
+     * <p>
+     *
+     * @param trace
+     *            the trace being queried
+     * @param adapterType
+     *            the type of adapter to look up
+     * @return a list of objects of the given adapter type
+     */
+    public static <T> List<T> getAdapters(ITmfTrace trace, Class<T> adapterType) {
+        Collection<IAdapterFactory> factoriesById = fFactoriesById.get(trace.getTraceTypeId());
+        Collection<Entry<Class<? extends ITmfTrace>, IAdapterFactory>> entries = fFactoriesByClass.entries();
+        List<T> adapters = new ArrayList<>(factoriesById.size() + entries.size());
+        for (IAdapterFactory factory : factoriesById) {
+            T adapter = factory.getAdapter(trace, adapterType);
+            if (adapter != null) {
+                adapters.add(adapter);
+            }
+        }
+        for (Entry<Class<? extends ITmfTrace>, IAdapterFactory> entry : entries) {
+            if (entry.getKey().isInstance(trace)) {
+                T adapter = entry.getValue().getAdapter(trace, adapterType);
+                if (adapter != null) {
+                    adapters.add(adapter);
+                }
+            }
+        }
+        return adapters;
+    }
+
+}