4 files changed, 38 insertions, 31 deletions
diff --git a/src/org/traccar/protocol/AisProtocolDecoder.java b/src/org/traccar/protocol/AisProtocolDecoder.java
index 3ccca6dd3..f04c558c2 100644
--- a/src/org/traccar/protocol/AisProtocolDecoder.java
+++ b/src/org/traccar/protocol/AisProtocolDecoder.java
@@ -24,6 +24,7 @@ import org.traccar.helper.PatternBuilder;
 import org.traccar.model.Position;
 
 import java.net.SocketAddress;
+import java.nio.charset.StandardCharsets;
 import java.util.ArrayList;
 import java.util.Date;
 import java.util.HashMap;
@@ -110,7 +111,7 @@ public class AisProtocolDecoder extends BaseProtocolDecoder {
 
                     if (count == 1) {
                         BitBuffer bits = new BitBuffer();
-                        bits.writeEncoded(parser.next().getBytes());
+                        bits.writeEncoded(parser.next().getBytes(StandardCharsets.US_ASCII));
                         position = decodePayload(channel, remoteAddress, bits);
                     } else {
                         BitBuffer bits = buffers.get(id);
@@ -118,7 +119,7 @@ public class AisProtocolDecoder extends BaseProtocolDecoder {
                             bits = new BitBuffer();
                             buffers.put(id, bits);
                         }
-                        bits.writeEncoded(parser.next().getBytes());
+                        bits.writeEncoded(parser.next().getBytes(StandardCharsets.US_ASCII));
                         if (count == index) {
                             position = decodePayload(channel, remoteAddress, bits);
                             buffers.remove(id);
diff --git a/src/org/traccar/protocol/At2000FrameDecoder.java b/src/org/traccar/protocol/At2000FrameDecoder.java
index f87dc3885..af257d0fb 100644
--- a/src/org/traccar/protocol/At2000FrameDecoder.java
+++ b/src/org/traccar/protocol/At2000FrameDecoder.java
@@ -65,12 +65,11 @@ public class At2000FrameDecoder extends FrameDecoder {
             length = (length / BLOCK_LENGTH + 1) * BLOCK_LENGTH;
         }
 
-        if (buf.readableBytes() >= length || buf.readableBytes() % ACK_LENGTH == 0) {
-            if (buf != currentBuffer || buf.readableBytes() > acknowledgedBytes) {
-                sendResponse(channel);
-                currentBuffer = buf;
-                acknowledgedBytes = buf.readableBytes();
-            }
+        if ((buf.readableBytes() >= length || buf.readableBytes() % ACK_LENGTH == 0)
+                && (buf != currentBuffer || buf.readableBytes() > acknowledgedBytes)) {
+            sendResponse(channel);
+            currentBuffer = buf;
+            acknowledgedBytes = buf.readableBytes();
         }
 
         if (buf.readableBytes() >= length) {
diff --git a/src/org/traccar/protocol/H02FrameDecoder.java b/src/org/traccar/protocol/H02FrameDecoder.java
index b2da64847..f1d305ab6 100644
--- a/src/org/traccar/protocol/H02FrameDecoder.java
+++ b/src/org/traccar/protocol/H02FrameDecoder.java
@@ -44,34 +44,44 @@ public class H02FrameDecoder extends FrameDecoder {
             }
         }
 
-        if (marker == '*') {
+        switch (marker) {
+            case '*':
 
-            // Return text message
-            int index = buf.indexOf(buf.readerIndex(), buf.writerIndex(), (byte) '#');
-            if (index != -1) {
-                return buf.readBytes(index + 1 - buf.readerIndex());
-            }
+                // Return text message
+                int index = buf.indexOf(buf.readerIndex(), buf.writerIndex(), (byte) '#');
+                if (index != -1) {
+                    return buf.readBytes(index + 1 - buf.readerIndex());
+                }
+
+                break;
 
-        } else if (marker == '$') {
+            case '$':
 
-            if (messageLength == 0) {
-                if (buf.readableBytes() == MESSAGE_LONG) {
-                    messageLength = MESSAGE_LONG;
-                } else {
-                    messageLength = MESSAGE_SHORT;
+                if (messageLength == 0) {
+                    if (buf.readableBytes() == MESSAGE_LONG) {
+                        messageLength = MESSAGE_LONG;
+                    } else {
+                        messageLength = MESSAGE_SHORT;
+                    }
                 }
-            }
 
-            if (buf.readableBytes() >= messageLength) {
-                return buf.readBytes(messageLength);
-            }
+                if (buf.readableBytes() >= messageLength) {
+                    return buf.readBytes(messageLength);
+                }
 
-        } else if (marker == 'X') {
+                break;
 
-            if (buf.readableBytes() >= MESSAGE_SHORT) {
-                return buf.readBytes(MESSAGE_SHORT);
-            }
+            case 'X':
+
+                if (buf.readableBytes() >= MESSAGE_SHORT) {
+                    return buf.readBytes(MESSAGE_SHORT);
+                }
+
+                break;
+
+            default:
 
+                throw new IllegalArgumentException();
         }
 
         return null;
diff --git a/src/org/traccar/protocol/TmgProtocolDecoder.java b/src/org/traccar/protocol/TmgProtocolDecoder.java
index 3a2af96fb..2f2dddf60 100644
--- a/src/org/traccar/protocol/TmgProtocolDecoder.java
+++ b/src/org/traccar/protocol/TmgProtocolDecoder.java
@@ -67,9 +67,6 @@ public class TmgProtocolDecoder extends BaseProtocolDecoder {
     protected Object decode(
             Channel channel, SocketAddress remoteAddress, Object msg) throws Exception {
 
-        org.traccar.helper.PatternUtil.MatchResult matchResult =
-                org.traccar.helper.PatternUtil.checkPattern(PATTERN.pattern(), (String) msg);
-
         Parser parser = new Parser(PATTERN, (String) msg);
         if (!parser.matches()) {
             return null;