From: Erik Brakkee <erik@brakkee.org>
Date: Sun, 26 Mar 2006 21:15:04 +0000 (+0000)
Subject: (no commit message)
X-Git-Tag: wamblee-utils-0.7~1068
X-Git-Url: http://wamblee.org/gitweb/?a=commitdiff_plain;h=c4f77c8bcc4f972a7b98fe78f6fba49bed43da0b;p=utils

---

diff --git a/support/test/org/wamblee/test/EventTracker.java b/support/test/org/wamblee/test/EventTracker.java
new file mode 100644
index 00000000..e49e671c
--- /dev/null
+++ b/support/test/org/wamblee/test/EventTracker.java
@@ -0,0 +1,125 @@
+/*
+ * Copyright 2006 the original author or authors.
+ * 
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ * 
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ * 
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+package org.wamblee.test;
+
+import java.util.ArrayList;
+import java.util.Collections;
+import java.util.HashMap;
+import java.util.List;
+import java.util.Map;
+
+import org.apache.commons.logging.Log;
+import org.apache.commons.logging.LogFactory;
+
+/**
+ * Tracks the occurence of certain events in a test environment. Threads in a
+ * test environment tell the event tracker of the occurrence of certain events
+ * using {@link #eventOccurred(String)}. Test code inspects the events sent by
+ * a thread using {@link #isEventSent(Thread, String)}.
+ * 
+ * A record is kept of every event which is sent. Therefore, the occurence of a
+ * new event does not erase a previously sent event.
+ * 
+ * @param <Event> Type of event sent from test code. Usually String will be sufficient. 
+ *    The event type must provide a sensible implementation of {@link java.lang.Object#equals(java.lang.Object)}. 
+ */
+public class EventTracker<Event> {
+
+    private static final Log LOG = LogFactory.getLog(EventTracker.class);
+
+    /**
+     * Map of Thread object to a list of events.
+     */
+    private Map<Thread, List<Event>> _events;
+
+    /**
+     * Constructs the event tracker.
+     * 
+     */
+    public EventTracker() {
+        _events = new HashMap<Thread, List<Event>>();
+    }
+
+    /**
+     * Called by a thread to inform that an event has occurred.
+     * 
+     * @param aEvent
+     *            Event that was sent.
+     */
+    public synchronized void eventOccurred(Event aEvent) {
+        LOG.info("Event '" + aEvent + "' sent.");
+        Thread current = Thread.currentThread();
+        List<Event> events = _events.get(current);
+        if (events == null) {
+            events = new ArrayList<Event>();
+            _events.put(current, events);
+        }
+        events.add(aEvent);
+    }
+
+    /**
+     * Checks if a specific event has happened in a specific thread.
+     * 
+     * @param aThread
+     *            Thread to check.
+     * @param aEvent
+     *            Event to check for.
+     * @return Whether or not the event was sent.
+     */
+    public synchronized boolean isEventSent(Thread aThread, Event aEvent) {
+        List<Event> events = _events.get(aThread);
+        if (events == null) {
+            return false;
+        }
+        return events.contains(aEvent);
+    }
+
+    /**
+     * Gets the events for a thread in the order they were sent
+     * 
+     * @param aThread
+     *            Thread to get events for.
+     * @return Events that were sent. A zero-sized array is returned if no
+     *         events were sent.
+     */
+    public synchronized List<Event> getEvents(Thread aThread) {
+        List<Event> events = _events.get(aThread);
+        if (events == null) {
+            events = Collections.emptyList();
+        }
+        return Collections.unmodifiableList(events);
+    }
+
+    /**
+     * Gets the number of times an event was sent.
+     * 
+     * @param aEvent
+     *            Event to check.
+     * @return Number of times it was reached.
+     */
+    public synchronized int getEventCount(Event aEvent) {
+        int count = 0;
+        for (Thread thread : _events.keySet()) {
+            List<Event> events = _events.get(thread);
+            for (Event event : events) {
+                if (event.equals(aEvent)) {
+                    count++;
+                }
+            }
+        }
+        return count;
+    }
+}