refactor duplicated read/write methods

usbSerialForAndroid/src/main/java/com/hoho/android/usbserial/driver/CdcAcmSerialDriver.java

@@ -26,11 +26,9 @@ import android.hardware.usb.UsbDevice;
 import android.hardware.usb.UsbDeviceConnection;
 import android.hardware.usb.UsbEndpoint;
 import android.hardware.usb.UsbInterface;
-import android.hardware.usb.UsbRequest;
 import android.util.Log;
 
 import java.io.IOException;
-import java.nio.ByteBuffer;
 import java.util.Collections;
 import java.util.LinkedHashMap;
 import java.util.List;
@@ -50,7 +48,6 @@ public class CdcAcmSerialDriver implements UsbSerialDriver {
 
     private final UsbDevice mDevice;
     private final UsbSerialPort mPort;
-    private UsbRequest mUsbRequest;
 
     public CdcAcmSerialDriver(UsbDevice device) {
         mDevice = device;
@@ -73,8 +70,6 @@ public class CdcAcmSerialDriver implements UsbSerialDriver {
         private UsbInterface mDataInterface;
 
         private UsbEndpoint mControlEndpoint;
-        private UsbEndpoint mReadEndpoint;
-        private UsbEndpoint mWriteEndpoint;
 
         private int mControlIndex;
 
@@ -266,78 +261,6 @@ public class CdcAcmSerialDriver implements UsbSerialDriver {
             }
         }
 
-        @Override
-        public int read(byte[] dest, int timeoutMillis) throws IOException {
-            if(mConnection == null) {
-                throw new IOException("Connection closed");
-            }
-            final UsbRequest request = new UsbRequest();
-            try {
-                request.initialize(mConnection, mReadEndpoint);
-                final ByteBuffer buf = ByteBuffer.wrap(dest);
-                if (!request.queue(buf, dest.length)) {
-                    throw new IOException("Error queueing request");
-                }
-                mUsbRequest = request;
-                final UsbRequest response = mConnection.requestWait();
-                synchronized (this) {
-                    mUsbRequest = null;
-                }
-                if (response == null) {
-                    throw new IOException("Null response");
-                }
-
-                final int nread = buf.position();
-                if (nread > 0) {
-                    //Log.d(TAG, HexDump.dumpHexString(dest, 0, Math.min(32, dest.length)));
-                    return nread;
-                } else {
-                    return 0;
-                }
-            } finally {
-                mUsbRequest = null;
-                request.close();
-            }
-        }
-
-        @Override
-        public int write(byte[] src, int timeoutMillis) throws IOException {
-            // TODO(mikey): Nearly identical to FtdiSerial write. Refactor.
-            int offset = 0;
-
-            if(mConnection == null) {
-                throw new IOException("Connection closed");
-            }
-            while (offset < src.length) {
-                final int writeLength;
-                final int amtWritten;
-
-                synchronized (mWriteBufferLock) {
-                    final byte[] writeBuffer;
-
-                    writeLength = Math.min(src.length - offset, mWriteBuffer.length);
-                    if (offset == 0) {
-                        writeBuffer = src;
-                    } else {
-                        // bulkTransfer does not support offsets, make a copy.
-                        System.arraycopy(src, offset, mWriteBuffer, 0, writeLength);
-                        writeBuffer = mWriteBuffer;
-                    }
-
-                    amtWritten = mConnection.bulkTransfer(mWriteEndpoint, writeBuffer, writeLength,
-                            timeoutMillis);
-                }
-                if (amtWritten <= 0) {
-                    throw new IOException("Error writing " + writeLength
-                            + " bytes at offset " + offset + " length=" + src.length);
-                }
-
-                Log.d(TAG, "Wrote amt=" + amtWritten + " attempted=" + writeLength);
-                offset += amtWritten;
-            }
-            return offset;
-        }
-
         @Override
         public void setParameters(int baudRate, int dataBits, int stopBits, int parity) throws IOException {
             if(baudRate <= 0) {

usbSerialForAndroid/src/main/java/com/hoho/android/usbserial/driver/Ch34xSerialDriver.java

@@ -25,11 +25,8 @@ import android.hardware.usb.UsbDevice;
 import android.hardware.usb.UsbDeviceConnection;
 import android.hardware.usb.UsbEndpoint;
 import android.hardware.usb.UsbInterface;
-import android.hardware.usb.UsbRequest;
-import android.util.Log;
 
 import java.io.IOException;
-import java.nio.ByteBuffer;
 import java.util.Collections;
 import java.util.LinkedHashMap;
 import java.util.List;
@@ -83,10 +80,6 @@ public class Ch34xSerialDriver implements UsbSerialDriver {
 		private boolean dtr = false;
 		private boolean rts = false;
 
-		private UsbEndpoint mReadEndpoint;
-		private UsbEndpoint mWriteEndpoint;
-		private UsbRequest mUsbRequest;
-
 		public Ch340SerialPort(UsbDevice device, int portNumber) {
 			super(device, portNumber);
 		}
@@ -155,78 +148,6 @@ public class Ch34xSerialDriver implements UsbSerialDriver {
 			}
 		}
 
-
-		@Override
-		public int read(byte[] dest, int timeoutMillis) throws IOException {
-			if(mConnection == null) {
-				throw new IOException("Connection closed");
-			}
-			final UsbRequest request = new UsbRequest();
-			try {
-				request.initialize(mConnection, mReadEndpoint);
-				final ByteBuffer buf = ByteBuffer.wrap(dest);
-				if (!request.queue(buf, dest.length)) {
-					throw new IOException("Error queueing request");
-				}
-				mUsbRequest = request;
-				final UsbRequest response = mConnection.requestWait();
-				synchronized (this) {
-					mUsbRequest = null;
-				}
-				if (response == null) {
-					throw new IOException("Null response");
-				}
-
-				final int nread = buf.position();
-				if (nread > 0) {
-					//Log.d(TAG, HexDump.dumpHexString(dest, 0, Math.min(32, dest.length)));
-					return nread;
-				} else {
-					return 0;
-				}
-			} finally {
-				mUsbRequest = null;
-				request.close();
-			}
-		}
-
-		@Override
-		public int write(byte[] src, int timeoutMillis) throws IOException {
-			int offset = 0;
-
-			if(mConnection == null) {
-				throw new IOException("Connection closed");
-			}
-			while (offset < src.length) {
-				final int writeLength;
-				final int amtWritten;
-
-				synchronized (mWriteBufferLock) {
-					final byte[] writeBuffer;
-
-					writeLength = Math.min(src.length - offset, mWriteBuffer.length);
-					if (offset == 0) {
-						writeBuffer = src;
-					} else {
-						// bulkTransfer does not support offsets, make a copy.
-						System.arraycopy(src, offset, mWriteBuffer, 0, writeLength);
-						writeBuffer = mWriteBuffer;
-					}
-
-					amtWritten = mConnection.bulkTransfer(mWriteEndpoint, writeBuffer, writeLength,
-							timeoutMillis);
-				}
-				if (amtWritten <= 0) {
-					throw new IOException("Error writing " + writeLength
-							+ " bytes at offset " + offset + " length=" + src.length);
-				}
-
-				Log.d(TAG, "Wrote amt=" + amtWritten + " attempted=" + writeLength);
-				offset += amtWritten;
-			}
-			return offset;
-		}
-
 		private int controlOut(int request, int value, int index) {
 			final int REQTYPE_HOST_TO_DEVICE = 0x41;
 			return mConnection.controlTransfer(REQTYPE_HOST_TO_DEVICE, request,

usbSerialForAndroid/src/main/java/com/hoho/android/usbserial/driver/CommonUsbSerialPort.java

@@ -23,8 +23,12 @@ package com.hoho.android.usbserial.driver;
 
 import android.hardware.usb.UsbDevice;
 import android.hardware.usb.UsbDeviceConnection;
+import android.hardware.usb.UsbEndpoint;
+import android.hardware.usb.UsbRequest;
+import android.util.Log;
 
 import java.io.IOException;
+import java.nio.ByteBuffer;
 
 /**
  * A base class shared by several driver implementations.
@@ -33,16 +37,19 @@ import java.io.IOException;
  */
 public abstract class CommonUsbSerialPort implements UsbSerialPort {
 
-    public static final int DEFAULT_WRITE_BUFFER_SIZE = 16 * 1024;
+    private static final String TAG = CommonUsbSerialPort.class.getSimpleName();
+    private static final int DEFAULT_WRITE_BUFFER_SIZE = 16 * 1024;
 
     protected final UsbDevice mDevice;
     protected final int mPortNumber;
 
     // non-null when open()
     protected UsbDeviceConnection mConnection = null;
+    protected UsbEndpoint mReadEndpoint;
+    protected UsbEndpoint mWriteEndpoint;
+    protected UsbRequest mUsbRequest;
 
     protected final Object mWriteBufferLock = new Object();
-
     /** Internal write buffer.  Guarded by {@link #mWriteBufferLock}. */
     protected byte[] mWriteBuffer;
 
@@ -52,7 +59,7 @@ public abstract class CommonUsbSerialPort implements UsbSerialPort {
 
         mWriteBuffer = new byte[DEFAULT_WRITE_BUFFER_SIZE];
     }
-    
+
     @Override
     public String toString() {
         return String.format("<%s device_name=%s device_id=%s port_number=%s>",
@@ -105,10 +112,76 @@ public abstract class CommonUsbSerialPort implements UsbSerialPort {
     public abstract void close() throws IOException;
 
     @Override
-    public abstract int read(final byte[] dest, final int timeoutMillis) throws IOException;
+    public int read(final byte[] dest, final int timeoutMillis) throws IOException {
+        if(mConnection == null) {
+            throw new IOException("Connection closed");
+        }
+        final UsbRequest request = new UsbRequest();
+        try {
+            request.initialize(mConnection, mReadEndpoint);
+            final ByteBuffer buf = ByteBuffer.wrap(dest);
+            if (!request.queue(buf, dest.length)) {
+                throw new IOException("Error queueing request");
+            }
+            mUsbRequest = request;
+            final UsbRequest response = mConnection.requestWait();
+            synchronized (this) {
+                mUsbRequest = null;
+            }
+            if (response == null) {
+                throw new IOException("Null response");
+            }
+            final int nread = buf.position();
+            if (nread > 0) {
+                return readFilter(dest, nread);
+            } else {
+                return 0;
+            }
+        } finally {
+            mUsbRequest = null;
+            request.close();
+        }
+    }
+
+    protected int readFilter(final byte[] buffer, int len) throws IOException { return len; }
 
     @Override
-    public abstract int write(final byte[] src, final int timeoutMillis) throws IOException;
+    public int write(final byte[] src, final int timeoutMillis) throws IOException {
+        int offset = 0;
+
+        if(mConnection == null) {
+            throw new IOException("Connection closed");
+        }
+        while (offset < src.length) {
+            final int writeLength;
+            final int amtWritten;
+
+            synchronized (mWriteBufferLock) {
+                final byte[] writeBuffer;
+
+                writeLength = Math.min(src.length - offset, mWriteBuffer.length);
+                if (offset == 0) {
+                    writeBuffer = src;
+                } else {
+                    // bulkTransfer does not support offsets, make a copy.
+                    System.arraycopy(src, offset, mWriteBuffer, 0, writeLength);
+                    writeBuffer = mWriteBuffer;
+                }
+
+                amtWritten = mConnection.bulkTransfer(mWriteEndpoint, writeBuffer, writeLength,
+                        timeoutMillis);
+            }
+            if (amtWritten <= 0) {
+                throw new IOException("Error writing " + writeLength
+                        + " bytes at offset " + offset + " length=" + src.length);
+            }
+
+            Log.d(TAG, "Wrote amt=" + amtWritten + " attempted=" + writeLength);
+            offset += amtWritten;
+        }
+        return offset;
+    }
+
 
     @Override
     public abstract void setParameters(int baudRate, int dataBits, int stopBits, int parity) throws IOException;

usbSerialForAndroid/src/main/java/com/hoho/android/usbserial/driver/Cp21xxSerialDriver.java

@@ -26,11 +26,8 @@ import android.hardware.usb.UsbDevice;
 import android.hardware.usb.UsbDeviceConnection;
 import android.hardware.usb.UsbEndpoint;
 import android.hardware.usb.UsbInterface;
-import android.hardware.usb.UsbRequest;
-import android.util.Log;
 
 import java.io.IOException;
-import java.nio.ByteBuffer;
 import java.util.ArrayList;
 import java.util.LinkedHashMap;
 import java.util.List;
@@ -106,10 +103,6 @@ public class Cp21xxSerialDriver implements UsbSerialDriver {
         private static final int CONTROL_WRITE_DTR = 0x0100;
         private static final int CONTROL_WRITE_RTS = 0x0200;
 
-        private UsbEndpoint mReadEndpoint;
-        private UsbEndpoint mWriteEndpoint;
-        private UsbRequest mUsbRequest;
-
         // second port of Cp2105 has limited baudRate, dataBits, stopBits, parity
         // unsupported baudrate returns error at controlTransfer(), other parameters are silently ignored
         private boolean mIsRestrictedPort;
@@ -195,77 +188,6 @@ public class Cp21xxSerialDriver implements UsbSerialDriver {
             }
         }
 
-        @Override
-        public int read(byte[] dest, int timeoutMillis) throws IOException {
-            if(mConnection == null) {
-                throw new IOException("Connection closed");
-            }
-            final UsbRequest request = new UsbRequest();
-            try {
-                request.initialize(mConnection, mReadEndpoint);
-                final ByteBuffer buf = ByteBuffer.wrap(dest);
-                if (!request.queue(buf, dest.length)) {
-                    throw new IOException("Error queueing request");
-                }
-                mUsbRequest = request;
-                final UsbRequest response = mConnection.requestWait();
-                synchronized (this) {
-                    mUsbRequest = null;
-                }
-                if (response == null) {
-                    throw new IOException("Null response");
-                }
-
-                final int nread = buf.position();
-                if (nread > 0) {
-                    //Log.d(TAG, HexDump.dumpHexString(dest, 0, Math.min(32, dest.length)));
-                    return nread;
-                } else {
-                    return 0;
-                }
-            } finally {
-                mUsbRequest = null;
-                request.close();
-            }
-        }
-
-        @Override
-        public int write(byte[] src, int timeoutMillis) throws IOException {
-            int offset = 0;
-
-            if(mConnection == null) {
-                throw new IOException("Connection closed");
-            }
-            while (offset < src.length) {
-                final int writeLength;
-                final int amtWritten;
-
-                synchronized (mWriteBufferLock) {
-                    final byte[] writeBuffer;
-
-                    writeLength = Math.min(src.length - offset, mWriteBuffer.length);
-                    if (offset == 0) {
-                        writeBuffer = src;
-                    } else {
-                        // bulkTransfer does not support offsets, make a copy.
-                        System.arraycopy(src, offset, mWriteBuffer, 0, writeLength);
-                        writeBuffer = mWriteBuffer;
-                    }
-
-                    amtWritten = mConnection.bulkTransfer(mWriteEndpoint, writeBuffer, writeLength,
-                            timeoutMillis);
-                }
-                if (amtWritten <= 0) {
-                    throw new IOException("Error writing " + writeLength
-                            + " bytes at offset " + offset + " length=" + src.length);
-                }
-
-                Log.d(TAG, "Wrote amt=" + amtWritten + " attempted=" + writeLength);
-                offset += amtWritten;
-            }
-            return offset;
-        }
-
         private void setBaudRate(int baudRate) throws IOException {
             byte[] data = new byte[] {
                     (byte) ( baudRate & 0xff),

usbSerialForAndroid/src/main/java/com/hoho/android/usbserial/driver/FtdiSerialDriver.java

@@ -24,12 +24,9 @@ package com.hoho.android.usbserial.driver;
 import android.hardware.usb.UsbConstants;
 import android.hardware.usb.UsbDevice;
 import android.hardware.usb.UsbDeviceConnection;
-import android.hardware.usb.UsbEndpoint;
-import android.hardware.usb.UsbRequest;
 import android.util.Log;
 
 import java.io.IOException;
-import java.nio.ByteBuffer;
 import java.util.ArrayList;
 import java.util.LinkedHashMap;
 import java.util.List;
@@ -196,31 +193,32 @@ public class FtdiSerialDriver implements UsbSerialDriver {
 
         /**
          * Filter FTDI status bytes from buffer
-         * @param src The source buffer (which contains status bytes)
+         * @param buffer The source buffer (which contains status bytes)
-         * @param dest The destination buffer to write the status bytes into (can be src)
+         *        buffer The destination buffer to write the status bytes into (can be src)
          * @param totalBytesRead Number of bytes read to src
-         * @param maxPacketSize The USB endpoint max packet size
          * @return The number of payload bytes
          */
-        private final int filterStatusBytes(byte[] src, byte[] dest, int totalBytesRead, int maxPacketSize) {
+        @Override
+        protected int readFilter(byte[] buffer, int totalBytesRead) throws IOException {
+            if (totalBytesRead < MODEM_STATUS_HEADER_LENGTH) {
+                throw new IOException("Expected at least " + MODEM_STATUS_HEADER_LENGTH + " bytes");
+            }
+            int maxPacketSize = mReadEndpoint.getMaxPacketSize();
             final int packetsCount = (totalBytesRead + maxPacketSize -1 )/ maxPacketSize;
             for (int packetIdx = 0; packetIdx < packetsCount; ++packetIdx) {
                 final int count = (packetIdx == (packetsCount - 1))
                         ? totalBytesRead - packetIdx * maxPacketSize - MODEM_STATUS_HEADER_LENGTH
                         : maxPacketSize - MODEM_STATUS_HEADER_LENGTH;
                 if (count > 0) {
-                    System.arraycopy(src,
+                    System.arraycopy(buffer, packetIdx * maxPacketSize + MODEM_STATUS_HEADER_LENGTH,
-                            packetIdx * maxPacketSize + MODEM_STATUS_HEADER_LENGTH,
+                                     buffer, packetIdx * (maxPacketSize - MODEM_STATUS_HEADER_LENGTH),
-                            dest,
+                                     count);
-                            packetIdx * (maxPacketSize - MODEM_STATUS_HEADER_LENGTH),
-                            count);
                 }
             }
-
+            return totalBytesRead - (packetsCount * 2);
-          return totalBytesRead - (packetsCount * 2);
         }
 
-        public void reset() throws IOException {
+        void reset() throws IOException {
             // TODO(mikey): autodetect.
             mType = DeviceType.TYPE_R;
             if(mDevice.getInterfaceCount() > 1) {
@@ -252,6 +250,12 @@ public class FtdiSerialDriver implements UsbSerialDriver {
                 } else {
                     throw new IOException("Error claiming interface " + mPortNumber);
                 }
+                if (mDevice.getInterface(mPortNumber).getEndpointCount() < 2) {
+                    throw new IOException("Insufficient number of endpoints (" +
+                            mDevice.getInterface(mPortNumber).getEndpointCount() + ")");
+                }
+                mReadEndpoint = mDevice.getInterface(mPortNumber).getEndpoint(0);
+                mWriteEndpoint = mDevice.getInterface(mPortNumber).getEndpoint(1);
                 reset();
                 opened = true;
             } finally {
@@ -276,75 +280,6 @@ public class FtdiSerialDriver implements UsbSerialDriver {
             }
         }
 
-        @Override
-        public int read(byte[] dest, int timeoutMillis) throws IOException {
-            if(mConnection == null) {
-                throw new IOException("Connection closed");
-            }
-            final UsbEndpoint endpoint = mDevice.getInterface(mPortNumber).getEndpoint(0);
-            final UsbRequest request = new UsbRequest();
-            final ByteBuffer buf = ByteBuffer.wrap(dest);
-            try {
-                request.initialize(mConnection, endpoint);
-                if (!request.queue(buf, dest.length)) {
-                    throw new IOException("Error queueing request");
-                }
-
-                final UsbRequest response = mConnection.requestWait();
-                if (response == null) {
-                    throw new IOException("Null response");
-                }
-            } finally {
-                request.close();
-            }
-
-            final int totalBytesRead = buf.position();
-            if (totalBytesRead < MODEM_STATUS_HEADER_LENGTH) {
-                throw new IOException("Expected at least " + MODEM_STATUS_HEADER_LENGTH + " bytes");
-            }
-
-            return filterStatusBytes(dest, dest, totalBytesRead, endpoint.getMaxPacketSize());
-        }
-
-        @Override
-        public int write(byte[] src, int timeoutMillis) throws IOException {
-            if(mConnection == null) {
-                throw new IOException("Connection closed");
-            }
-            final UsbEndpoint endpoint = mDevice.getInterface(mPortNumber).getEndpoint(1);
-            int offset = 0;
-
-            while (offset < src.length) {
-                final int writeLength;
-                final int amtWritten;
-
-                synchronized (mWriteBufferLock) {
-                    final byte[] writeBuffer;
-
-                    writeLength = Math.min(src.length - offset, mWriteBuffer.length);
-                    if (offset == 0) {
-                        writeBuffer = src;
-                    } else {
-                        // bulkTransfer does not support offsets, make a copy.
-                        System.arraycopy(src, offset, mWriteBuffer, 0, writeLength);
-                        writeBuffer = mWriteBuffer;
-                    }
-
-                    amtWritten = mConnection.bulkTransfer(endpoint, writeBuffer, writeLength,
-                            timeoutMillis);
-                }
-
-                if (amtWritten <= 0) {
-                    throw new IOException("Error writing " + writeLength
-                            + " bytes at offset " + offset + " length=" + src.length);
-                }
-
-                Log.d(TAG, "Wrote amtWritten=" + amtWritten + " attempted=" + writeLength);
-                offset += amtWritten;
-            }
-            return offset;
-        }
-
         private int setBaudRate(int baudRate) throws IOException {
             long[] vals = convertBaudrate(baudRate);
             long actualBaudrate = vals[0];

usbSerialForAndroid/src/main/java/com/hoho/android/usbserial/driver/ProlificSerialDriver.java

@@ -32,12 +32,10 @@ import android.hardware.usb.UsbDevice;
 import android.hardware.usb.UsbDeviceConnection;
 import android.hardware.usb.UsbEndpoint;
 import android.hardware.usb.UsbInterface;
-import android.hardware.usb.UsbRequest;
 import android.util.Log;
 
 import java.io.IOException;
 import java.lang.reflect.Method;
-import java.nio.ByteBuffer;
 import java.util.Collections;
 import java.util.LinkedHashMap;
 import java.util.List;
@@ -111,8 +109,6 @@ public class ProlificSerialDriver implements UsbSerialDriver {
 
         private int mDeviceType = DEVICE_TYPE_HX;
 
-        private UsbEndpoint mReadEndpoint;
-        private UsbEndpoint mWriteEndpoint;
         private UsbEndpoint mInterruptEndpoint;
 
         private int mControlLinesValue = 0;
@@ -370,74 +366,6 @@ public class ProlificSerialDriver implements UsbSerialDriver {
             }
         }
 
-        @Override
-        public int read(byte[] dest, int timeoutMillis) throws IOException {
-            if(mConnection == null) {
-                throw new IOException("Connection closed");
-            }
-            final UsbRequest request = new UsbRequest();
-            try {
-                request.initialize(mConnection, mReadEndpoint);
-                final ByteBuffer buf = ByteBuffer.wrap(dest);
-                if (!request.queue(buf, dest.length)) {
-                    throw new IOException("Error queueing request");
-                }
-
-                final UsbRequest response = mConnection.requestWait();
-                if (response == null) {
-                    throw new IOException("Null response");
-                }
-
-                final int nread = buf.position();
-                if (nread > 0) {
-                    //Log.d(TAG, HexDump.dumpHexString(dest, 0, Math.min(32, dest.length)));
-                    return nread;
-                } else {
-                    return 0;
-                }
-            } finally {
-                request.close();
-            }
-        }
-
-        @Override
-        public int write(byte[] src, int timeoutMillis) throws IOException {
-            int offset = 0;
-
-            if(mConnection == null) {
-                throw new IOException("Connection closed");
-            }
-            while (offset < src.length) {
-                final int writeLength;
-                final int amtWritten;
-
-                synchronized (mWriteBufferLock) {
-                    final byte[] writeBuffer;
-
-                    writeLength = Math.min(src.length - offset, mWriteBuffer.length);
-                    if (offset == 0) {
-                        writeBuffer = src;
-                    } else {
-                        // bulkTransfer does not support offsets, make a copy.
-                        System.arraycopy(src, offset, mWriteBuffer, 0, writeLength);
-                        writeBuffer = mWriteBuffer;
-                    }
-
-                    amtWritten = mConnection.bulkTransfer(mWriteEndpoint,
-                            writeBuffer, writeLength, timeoutMillis);
-                }
-
-                if (amtWritten <= 0) {
-                    throw new IOException("Error writing " + writeLength
-                            + " bytes at offset " + offset + " length="
-                            + src.length);
-                }
-
-                offset += amtWritten;
-            }
-            return offset;
-        }
-
         @Override
         public void setParameters(int baudRate, int dataBits, int stopBits, int parity) throws IOException {
             if ((mBaudRate == baudRate) && (mDataBits == dataBits)