Merge pull request taimos#1 from juzt3/speedlistener-function

juzt3 · juzt3 · commit e8fb9448fb92 · 2015-02-10T23:33:46.000-03:00
Speedlistener function
diff --git a/src/main/java/de/taimos/gpsd4java/api/SpeedListener.java b/src/main/java/de/taimos/gpsd4java/api/SpeedListener.java
@@ -0,0 +1,55 @@
+package de.taimos.gpsd4java.api;
+
+/*
+ * #%L
+ * GPSd4Java
+ * %%
+ * Copyright (C) 2011 - 2012 Taimos GmbH
+ * %%
+ * 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.
+ * #L%
+ */
+
+import de.taimos.gpsd4java.types.TPVObject;
+
+/**
+ * Derive this class to implement a listener for speed updates which reacts to changes smaller a given threshold
+ * 
+ * @author juzt3
+ */
+public abstract class SpeedListener extends ObjectListener {
+	
+	private TPVObject lastPosition;
+	
+	private final double threshold;
+	
+	
+	/**
+	 * @param threshold
+	 *            the threshold to fire in kilometers per hour
+	 */
+	public SpeedListener(final double threshold) {
+		this.threshold = threshold;
+	}
+	
+	@Override
+	public void handleTPV(final TPVObject tpv) {
+		if ((this.lastPosition == null) || (tpv.getSpeed() < this.threshold)) {
+			this.lastPosition = tpv;
+			this.handleLocation(tpv);
+		}
+	}
+	
+	protected abstract void handleLocation(TPVObject tpv);
+	
+}
