Implement bit utility class

5 files changed, 106 insertions, 92 deletions

diff --git a/src/org/traccar/helper/BitUtil.java b/src/org/traccar/helper/BitUtil.java
new file mode 100644
index 000000000..6e03e6d2a
--- /dev/null
+++ b/src/org/traccar/helper/BitUtil.java
@@ -0,0 +1,35 @@
+/*
+ * Copyright 2015 Anton Tananaev (anton.tananaev@gmail.com)
+ *
+ * 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.traccar.helper;
+
+/**
+ * Useful functions to work with bits
+ */
+public class BitUtil {
+    
+    public static boolean check(long number, int index) {
+        return (number & (1 << index)) != 0;
+    }
+    
+    public static int range(int number, int index, int length) {
+        return (number >> index) & ((1 << length) - 1);
+    }
+    
+    public static long range(long number, int index, int length) {
+        return (number >> index) & ((1l << length) - 1);
+    }
+    
+}
diff --git a/src/org/traccar/protocol/BceProtocolDecoder.java b/src/org/traccar/protocol/BceProtocolDecoder.java
index fa951e21d..189cad754 100644
--- a/src/org/traccar/protocol/BceProtocolDecoder.java
+++ b/src/org/traccar/protocol/BceProtocolDecoder.java
@@ -24,6 +24,7 @@ import org.jboss.netty.buffer.ChannelBuffers;
 import org.jboss.netty.channel.Channel;
 import org.jboss.netty.channel.ChannelHandlerContext;
 import org.traccar.BaseProtocolDecoder;
+import org.traccar.helper.BitUtil;
 import org.traccar.model.Event;
 import org.traccar.model.Position;
 
@@ -41,10 +42,6 @@ public class BceProtocolDecoder extends BaseProtocolDecoder {
     private static final int MSG_OUTPUT_CONTROL = 0x41;
     private static final int MSG_OUTPUT_CONTROL_ACK = 0xC1;
 
-    private static boolean checkBit(int mask, int bit) {
-        return (mask & (1 << bit)) != 0;
-    }
-
     @Override
     protected Object decode(
             ChannelHandlerContext ctx, Channel channel, Object msg)
@@ -86,11 +83,11 @@ public class BceProtocolDecoder extends BaseProtocolDecoder {
                     do {
                         mask = buf.readUnsignedShort();
                         masks.add(mask);
-                    } while (checkBit(mask, 15));
+                    } while (BitUtil.check(mask, 15));
 
                     mask = masks.get(0);
 
-                    if (checkBit(mask, 0)) {
+                    if (BitUtil.check(mask, 0)) {
                         position.setValid(true);
                         position.setLongitude(buf.readFloat());
                         position.setLatitude(buf.readFloat());
@@ -106,22 +103,22 @@ public class BceProtocolDecoder extends BaseProtocolDecoder {
                         position.set(Event.KEY_ODOMETER, buf.readUnsignedInt());
                     }
 
-                    if (checkBit(mask, 1)) {
+                    if (BitUtil.check(mask, 1)) {
                         position.set(Event.KEY_INPUT, buf.readUnsignedShort());
                     }
 
                     for (int i = 1; i <= 8; i++) {
-                        if (checkBit(mask, i + 1)) {
+                        if (BitUtil.check(mask, i + 1)) {
                             position.set(Event.PREFIX_ADC + i, buf.readUnsignedShort());
                         }
                     }
 
-                    if (checkBit(mask, 10)) buf.skipBytes(4);
-                    if (checkBit(mask, 11)) buf.skipBytes(4);
-                    if (checkBit(mask, 12)) buf.skipBytes(2);
-                    if (checkBit(mask, 13)) buf.skipBytes(2);
+                    if (BitUtil.check(mask, 10)) buf.skipBytes(4);
+                    if (BitUtil.check(mask, 11)) buf.skipBytes(4);
+                    if (BitUtil.check(mask, 12)) buf.skipBytes(2);
+                    if (BitUtil.check(mask, 13)) buf.skipBytes(2);
 
-                    if (checkBit(mask, 14)) {
+                    if (BitUtil.check(mask, 14)) {
                         position.set(Event.KEY_MCC, buf.readUnsignedShort());
                         position.set(Event.KEY_MNC, buf.readUnsignedByte());
                         position.set(Event.KEY_LAC, buf.readUnsignedShort());
@@ -130,7 +127,7 @@ public class BceProtocolDecoder extends BaseProtocolDecoder {
                         buf.readUnsignedByte();
                     }
 
-                    if (checkBit(mask, 0)) {
+                    if (BitUtil.check(mask, 0)) {
                         positions.add(position);
                     }
                 }
diff --git a/src/org/traccar/protocol/Mta6ProtocolDecoder.java b/src/org/traccar/protocol/Mta6ProtocolDecoder.java
index 7d4ead62c..459b8bcb8 100644
--- a/src/org/traccar/protocol/Mta6ProtocolDecoder.java
+++ b/src/org/traccar/protocol/Mta6ProtocolDecoder.java
@@ -21,7 +21,6 @@ import java.util.Date;
 import java.util.LinkedList;
 import java.util.List;
 import java.util.TimeZone;
-
 import org.jboss.netty.buffer.ChannelBuffer;
 import org.jboss.netty.buffer.ChannelBuffers;
 import org.jboss.netty.channel.Channel;
@@ -31,8 +30,8 @@ import org.jboss.netty.handler.codec.http.HttpRequest;
 import org.jboss.netty.handler.codec.http.HttpResponse;
 import org.jboss.netty.handler.codec.http.HttpResponseStatus;
 import org.jboss.netty.handler.codec.http.HttpVersion;
-
 import org.traccar.BaseProtocolDecoder;
+import org.traccar.helper.BitUtil;
 import org.traccar.helper.ChannelBufferTools;
 import org.traccar.model.Event;
 import org.traccar.model.Position;
@@ -66,11 +65,6 @@ public class Mta6ProtocolDecoder extends BaseProtocolDecoder {
         channel.write(response);
     }
     
-    private static boolean checkBit(long mask, int bit) {
-        long checkMask = 1 << bit;
-        return (mask & checkMask) == checkMask;
-    }
-    
     private static class FloatReader {
         
         private int previousFloat;
@@ -135,11 +129,11 @@ public class Mta6ProtocolDecoder extends BaseProtocolDecoder {
 
                 // Skip events
                 short event = buf.readUnsignedByte();
-                if (checkBit(event, 7)) {
-                    if (checkBit(event, 6)) {
+                if (BitUtil.check(event, 7)) {
+                    if (BitUtil.check(event, 6)) {
                         buf.skipBytes(8);
                     } else {
-                        while (checkBit(event, 7)) {
+                        while (BitUtil.check(event, 7)) {
                             event = buf.readUnsignedByte();
                         }
                     }
@@ -149,44 +143,44 @@ public class Mta6ProtocolDecoder extends BaseProtocolDecoder {
                 position.setLongitude(longitudeReader.readFloat(buf) / Math.PI * 180);
                 position.setTime(timeReader.readTime(buf));
 
-                if (checkBit(flags, 0)) {
+                if (BitUtil.check(flags, 0)) {
                     buf.readUnsignedByte(); // status
                 }
 
-                if (checkBit(flags, 1)) {
+                if (BitUtil.check(flags, 1)) {
                     position.setAltitude(buf.readUnsignedShort());
                 }
 
-                if (checkBit(flags, 2)) {
+                if (BitUtil.check(flags, 2)) {
                     position.setSpeed(buf.readUnsignedShort() & 0x03ff);
                     position.setCourse(buf.readUnsignedByte());
                 }
 
-                if (checkBit(flags, 3)) {
+                if (BitUtil.check(flags, 3)) {
                     position.set(Event.KEY_ODOMETER, buf.readUnsignedShort());
                 }
 
-                if (checkBit(flags, 4)) {
+                if (BitUtil.check(flags, 4)) {
                     position.set(Event.KEY_FUEL, buf.readUnsignedInt() + "|" + buf.readUnsignedInt());
                     position.set("hours1", buf.readUnsignedShort());
                     position.set("hours2", buf.readUnsignedShort());
                 }
 
-                if (checkBit(flags, 5)) {
+                if (BitUtil.check(flags, 5)) {
                     position.set(Event.PREFIX_ADC + 1, buf.readUnsignedShort() & 0x03ff);
                     position.set(Event.PREFIX_ADC + 2, buf.readUnsignedShort() & 0x03ff);
                     position.set(Event.PREFIX_ADC + 3, buf.readUnsignedShort() & 0x03ff);
                     position.set(Event.PREFIX_ADC + 4, buf.readUnsignedShort() & 0x03ff);
                 }
 
-                if (checkBit(flags, 6)) {
+                if (BitUtil.check(flags, 6)) {
                     position.set(Event.PREFIX_TEMP + 1, buf.readByte());
                     buf.getUnsignedByte(buf.readerIndex()); // control (>> 4)
                     position.set(Event.KEY_INPUT, buf.readUnsignedShort() & 0x0fff);
                     buf.readUnsignedShort(); // old sensor state (& 0x0fff)
                 }
 
-                if (checkBit(flags, 7)) {
+                if (BitUtil.check(flags, 7)) {
                     position.set(Event.KEY_BATTERY, buf.getUnsignedByte(buf.readerIndex()) >> 2);
                     position.set(Event.KEY_POWER, buf.readUnsignedShort() & 0x03ff);
                     buf.readByte(); // microcontroller temperature
@@ -214,11 +208,11 @@ public class Mta6ProtocolDecoder extends BaseProtocolDecoder {
 
         // Skip events
         short event = buf.readUnsignedByte();
-        if (checkBit(event, 7)) {
-            if (checkBit(event, 6)) {
+        if (BitUtil.check(event, 7)) {
+            if (BitUtil.check(event, 6)) {
                 buf.skipBytes(8);
             } else {
-                while (checkBit(event, 7)) {
+                while (BitUtil.check(event, 7)) {
                     event = buf.readUnsignedByte();
                 }
             }
@@ -230,41 +224,41 @@ public class Mta6ProtocolDecoder extends BaseProtocolDecoder {
 
         buf.readUnsignedByte(); // status
 
-        if (checkBit(flags, 0)) {
+        if (BitUtil.check(flags, 0)) {
             position.setAltitude(buf.readUnsignedShort());
             position.setSpeed(buf.readUnsignedByte());
             position.setCourse(buf.readByte());
             position.set(Event.KEY_ODOMETER, new FloatReader().readFloat(buf));
         }
 
-        if (checkBit(flags, 1)) {
+        if (BitUtil.check(flags, 1)) {
             new FloatReader().readFloat(buf); // fuel consumtion
             position.set("hours", new FloatReader().readFloat(buf));
             position.set("tank", buf.readUnsignedByte() * 0.4);
         }
 
-        if (checkBit(flags, 2)) {
+        if (BitUtil.check(flags, 2)) {
             position.set("engine", buf.readUnsignedShort() * 0.125);
             position.set("pedals", buf.readUnsignedByte());
             position.set(Event.PREFIX_TEMP + 1, buf.readUnsignedByte() - 40);
             buf.readUnsignedShort(); // service odometer
         }
 
-        if (checkBit(flags, 3)) {
+        if (BitUtil.check(flags, 3)) {
             position.set(Event.KEY_FUEL, buf.readUnsignedShort());
             position.set(Event.PREFIX_ADC + 2, buf.readUnsignedShort());
             position.set(Event.PREFIX_ADC + 3, buf.readUnsignedShort());
             position.set(Event.PREFIX_ADC + 4, buf.readUnsignedShort());
         }
 
-        if (checkBit(flags, 4)) {
+        if (BitUtil.check(flags, 4)) {
             position.set(Event.PREFIX_TEMP + 1, buf.readByte());
             buf.getUnsignedByte(buf.readerIndex()); // control (>> 4)
             position.set(Event.KEY_INPUT, buf.readUnsignedShort() & 0x0fff);
             buf.readUnsignedShort(); // old sensor state (& 0x0fff)
         }
 
-        if (checkBit(flags, 5)) {
+        if (BitUtil.check(flags, 5)) {
             position.set(Event.KEY_BATTERY, buf.getUnsignedByte(buf.readerIndex()) >> 2);
             position.set(Event.KEY_POWER, buf.readUnsignedShort() & 0x03ff);
             buf.readByte(); // microcontroller temperature
diff --git a/src/org/traccar/protocol/SkypatrolProtocolDecoder.java b/src/org/traccar/protocol/SkypatrolProtocolDecoder.java
index acb4fa5ec..5521502f6 100644
--- a/src/org/traccar/protocol/SkypatrolProtocolDecoder.java
+++ b/src/org/traccar/protocol/SkypatrolProtocolDecoder.java
@@ -18,12 +18,11 @@ package org.traccar.protocol;
 import java.nio.charset.Charset;
 import java.util.Calendar;
 import java.util.TimeZone;
-
 import org.jboss.netty.buffer.ChannelBuffer;
 import org.jboss.netty.channel.Channel;
 import org.jboss.netty.channel.ChannelHandlerContext;
-
 import org.traccar.BaseProtocolDecoder;
+import org.traccar.helper.BitUtil;
 import org.traccar.helper.Log;
 import org.traccar.model.Event;
 import org.traccar.model.Position;
@@ -34,11 +33,6 @@ public class SkypatrolProtocolDecoder extends BaseProtocolDecoder {
         super(protocol);
     }
 
-    private static boolean checkBit(long mask, int bit) {
-        long checkMask = 1 << bit;
-        return (mask & checkMask) == checkMask;
-    }
-
     private static double convertCoordinate(long coordinate) {
         int sign = 1;
         if (coordinate > 0x7fffffffl) {
@@ -73,23 +67,23 @@ public class SkypatrolProtocolDecoder extends BaseProtocolDecoder {
         if (apiNumber == 5 &&
             commandType == 2 &&
             messageType == 1 &&
-            checkBit(mask, 0)) {
+            BitUtil.check(mask, 0)) {
 
             // Create new position
             Position position = new Position();
             position.setProtocol(getProtocol());
 
             // Status code
-            if (checkBit(mask, 1)) {
+            if (BitUtil.check(mask, 1)) {
                 position.set(Event.KEY_STATUS, buf.readUnsignedInt());
             }
 
             // Device id
             String id = null;
-            if (checkBit(mask, 23)) {
+            if (BitUtil.check(mask, 23)) {
                 id = buf.toString(buf.readerIndex(), 8, Charset.defaultCharset()).trim();
                 buf.skipBytes(8);
-            } else if (checkBit(mask, 2)) {
+            } else if (BitUtil.check(mask, 2)) {
                 id = buf.toString(buf.readerIndex(), 22, Charset.defaultCharset()).trim();
                 buf.skipBytes(22);
             } else {
@@ -102,22 +96,22 @@ public class SkypatrolProtocolDecoder extends BaseProtocolDecoder {
             position.setDeviceId(getDeviceId());
 
             // IO data
-            if (checkBit(mask, 3)) {
+            if (BitUtil.check(mask, 3)) {
                 buf.readUnsignedShort();
             }
 
             // ADC 1
-            if (checkBit(mask, 4)) {
+            if (BitUtil.check(mask, 4)) {
                 buf.readUnsignedShort();
             }
 
             // ADC 2
-            if (checkBit(mask, 5)) {
+            if (BitUtil.check(mask, 5)) {
                 buf.readUnsignedShort();
             }
 
             // Function category
-            if (checkBit(mask, 7)) {
+            if (BitUtil.check(mask, 7)) {
                 buf.readUnsignedByte();
             }
 
@@ -125,39 +119,39 @@ public class SkypatrolProtocolDecoder extends BaseProtocolDecoder {
             time.clear();
 
             // Date
-            if (checkBit(mask, 8)) {
+            if (BitUtil.check(mask, 8)) {
                 time.set(Calendar.DAY_OF_MONTH, buf.readUnsignedByte());
                 time.set(Calendar.MONTH, buf.readUnsignedByte() - 1);
                 time.set(Calendar.YEAR, 2000 + buf.readUnsignedByte());
             }
 
             // GPS status
-            if (checkBit(mask, 9)) {
+            if (BitUtil.check(mask, 9)) {
                 position.setValid(buf.readUnsignedByte() == 1);
             }
 
             // Latitude
-            if (checkBit(mask, 10)) {
+            if (BitUtil.check(mask, 10)) {
                 position.setLatitude(convertCoordinate(buf.readUnsignedInt()));
             }
 
             // Longitude
-            if (checkBit(mask, 11)) {
+            if (BitUtil.check(mask, 11)) {
                 position.setLongitude(convertCoordinate(buf.readUnsignedInt()));
             }
 
             // Speed
-            if (checkBit(mask, 12)) {
+            if (BitUtil.check(mask, 12)) {
                 position.setSpeed(buf.readUnsignedShort() / 10.0);
             }
 
             // Course
-            if (checkBit(mask, 13)) {
+            if (BitUtil.check(mask, 13)) {
                 position.setCourse(buf.readUnsignedShort() / 10.0);
             }
 
             // Time
-            if (checkBit(mask, 14)) {
+            if (BitUtil.check(mask, 14)) {
                 time.set(Calendar.HOUR_OF_DAY, buf.readUnsignedByte());
                 time.set(Calendar.MINUTE, buf.readUnsignedByte());
                 time.set(Calendar.SECOND, buf.readUnsignedByte());
@@ -166,52 +160,52 @@ public class SkypatrolProtocolDecoder extends BaseProtocolDecoder {
             position.setTime(time.getTime());
 
             // Altitude
-            if (checkBit(mask, 15)) {
+            if (BitUtil.check(mask, 15)) {
                 position.setAltitude(buf.readMedium());
             }
 
             // Satellites
-            if (checkBit(mask, 16)) {
+            if (BitUtil.check(mask, 16)) {
                 position.set(Event.KEY_SATELLITES, buf.readUnsignedByte());
             }
 
             // Battery percentage
-            if (checkBit(mask, 17)) {
+            if (BitUtil.check(mask, 17)) {
                 buf.readUnsignedShort();
             }
 
             // Trip odometer
-            if (checkBit(mask, 20)) {
+            if (BitUtil.check(mask, 20)) {
                 position.set("trip", buf.readUnsignedInt());
             }
 
             // Odometer
-            if (checkBit(mask, 21)) {
+            if (BitUtil.check(mask, 21)) {
                 position.set(Event.KEY_ODOMETER, buf.readUnsignedInt());
             }
 
             // Time of message generation
-            if (checkBit(mask, 22)) {
+            if (BitUtil.check(mask, 22)) {
                 buf.skipBytes(6);
             }
 
             // Battery level
-            if (checkBit(mask, 24)) {
+            if (BitUtil.check(mask, 24)) {
                 position.set(Event.KEY_POWER, buf.readUnsignedShort() / 1000.0);
             }
 
             // GPS overspeed
-            if (checkBit(mask, 25)) {
+            if (BitUtil.check(mask, 25)) {
                 buf.skipBytes(18);
             }
 
             // Cell information
-            if (checkBit(mask, 26)) {
+            if (BitUtil.check(mask, 26)) {
                 buf.skipBytes(54);
             }
 
             // Sequence number
-            if (checkBit(mask, 28)) {
+            if (BitUtil.check(mask, 28)) {
                 position.set(Event.KEY_INDEX, buf.readUnsignedShort());
             }
 
diff --git a/src/org/traccar/protocol/TeltonikaProtocolDecoder.java b/src/org/traccar/protocol/TeltonikaProtocolDecoder.java
index d3e946f69..792a64b79 100644
--- a/src/org/traccar/protocol/TeltonikaProtocolDecoder.java
+++ b/src/org/traccar/protocol/TeltonikaProtocolDecoder.java
@@ -19,13 +19,12 @@ import java.nio.charset.Charset;
 import java.util.Date;
 import java.util.LinkedList;
 import java.util.List;
-
 import org.jboss.netty.buffer.ChannelBuffer;
 import org.jboss.netty.buffer.ChannelBuffers;
 import org.jboss.netty.channel.Channel;
 import org.jboss.netty.channel.ChannelHandlerContext;
-
 import org.traccar.BaseProtocolDecoder;
+import org.traccar.helper.BitUtil;
 import org.traccar.helper.UnitsConverter;
 import org.traccar.model.Event;
 import org.traccar.model.Position;
@@ -49,11 +48,6 @@ public class TeltonikaProtocolDecoder extends BaseProtocolDecoder {
         }
     }
 
-    private static boolean checkBit(long mask, int bit) {
-        long checkMask = 1 << bit;
-        return (mask & checkMask) == checkMask;
-    }
-
     private static final int CODEC_GH3000 = 0x07;
     private static final int CODEC_FM4X00 = 0x08;
     private static final int CODEC_12 = 0x0C;
@@ -87,45 +81,45 @@ public class TeltonikaProtocolDecoder extends BaseProtocolDecoder {
                 position.setTime(new Date(time * 1000));
                 
                 globalMask = buf.readUnsignedByte();
-                if (!checkBit(globalMask, 0)) {
+                if (!BitUtil.check(globalMask, 0)) {
                     return null;
                 }
                 
                 int locationMask = buf.readUnsignedByte();
                 
-                if (checkBit(locationMask, 0)) {
+                if (BitUtil.check(locationMask, 0)) {
                     position.setLatitude(buf.readFloat());
                     position.setLongitude(buf.readFloat());
                 }
                 
-                if (checkBit(locationMask, 1)) {
+                if (BitUtil.check(locationMask, 1)) {
                     position.setAltitude(buf.readUnsignedShort());
                 }
                 
-                if (checkBit(locationMask, 2)) {
+                if (BitUtil.check(locationMask, 2)) {
                     position.setCourse(buf.readUnsignedByte() * 360.0 / 256);
                 }
                 
-                if (checkBit(locationMask, 3)) {
+                if (BitUtil.check(locationMask, 3)) {
                     position.setSpeed(UnitsConverter.knotsFromKph(buf.readUnsignedByte()));
                 }
                 
-                if (checkBit(locationMask, 4)) {
+                if (BitUtil.check(locationMask, 4)) {
                     int satellites = buf.readUnsignedByte();
                     position.set(Event.KEY_SATELLITES, satellites);
                     position.setValid(satellites >= 3);
                 }
                 
-                if (checkBit(locationMask, 5)) {
+                if (BitUtil.check(locationMask, 5)) {
                     position.set("area", buf.readUnsignedShort());
                     position.set(Event.KEY_CELL, buf.readUnsignedShort());
                 }
                 
-                if (checkBit(locationMask, 6)) {
+                if (BitUtil.check(locationMask, 6)) {
                     position.set(Event.KEY_GSM, buf.readUnsignedByte());
                 }
                 
-                if (checkBit(locationMask, 7)) {
+                if (BitUtil.check(locationMask, 7)) {
                     position.set("operator", buf.readUnsignedInt());
                 }
 
@@ -154,7 +148,7 @@ public class TeltonikaProtocolDecoder extends BaseProtocolDecoder {
             }
             
             // Read 1 byte data
-            if (checkBit(globalMask, 1)) {
+            if (BitUtil.check(globalMask, 1)) {
                 int cnt = buf.readUnsignedByte();
                 for (int j = 0; j < cnt; j++) {
                     int id = buf.readUnsignedByte();
@@ -168,7 +162,7 @@ public class TeltonikaProtocolDecoder extends BaseProtocolDecoder {
 
             
             // Read 2 byte data
-            if (checkBit(globalMask, 2)) {
+            if (BitUtil.check(globalMask, 2)) {
                 int cnt = buf.readUnsignedByte();
                 for (int j = 0; j < cnt; j++) {
                     position.set(Event.PREFIX_IO + buf.readUnsignedByte(), buf.readUnsignedShort());
@@ -176,7 +170,7 @@ public class TeltonikaProtocolDecoder extends BaseProtocolDecoder {
             }
 
             // Read 4 byte data
-            if (checkBit(globalMask, 3)) {
+            if (BitUtil.check(globalMask, 3)) {
                 int cnt = buf.readUnsignedByte();
                 for (int j = 0; j < cnt; j++) {
                     position.set(Event.PREFIX_IO + buf.readUnsignedByte(), buf.readUnsignedInt());