throw UnsupportedOperationException instead of returning false

usbSerialForAndroid/build.gradle

@@ -15,6 +15,10 @@ android {
                 'rfc2217_server_nonstandard_baudrates': 'true',   // true    false     false
         ]
     }
+    compileOptions {
+        sourceCompatibility JavaVersion.VERSION_1_8
+        targetCompatibility JavaVersion.VERSION_1_8
+    }
 }
 
 dependencies {

usbSerialForAndroid/src/androidTest/java/com/hoho/android/usbserial/CrossoverTest.java

@@ -32,6 +32,7 @@ import static org.junit.Assert.assertEquals;
 import static org.junit.Assert.assertNotEquals;
 import static org.junit.Assert.assertThat;
 import static org.junit.Assert.fail;
+import static org.junit.Assume.assumeTrue;
 
 @RunWith(AndroidJUnit4.class)
 public class CrossoverTest {
@@ -51,6 +52,9 @@ public class CrossoverTest {
 
     @Before
     public void setUp() throws Exception {
+        assumeTrue("ignore test for device specific coverage report",
+                InstrumentationRegistry.getArguments().getString("test_device_driver") == null);
+
         context = InstrumentationRegistry.getContext();
         usbManager = (UsbManager) context.getSystemService(Context.USB_SERVICE);
         List<UsbSerialDriver> availableDrivers = UsbSerialProber.getDefaultProber().findAllDrivers(usbManager);

usbSerialForAndroid/src/androidTest/java/com/hoho/android/usbserial/DeviceTest.java

@@ -960,7 +960,13 @@ public class DeviceTest {
 
         usb.write(buf);
         Thread.sleep(50); // ~ 12 bytes
-        boolean purged = usb.serialPort.purgeHwBuffers(true, false);
+        boolean purged;
+        try {
+            usb.serialPort.purgeHwBuffers(true, false);
+            purged = true;
+        } catch (UnsupportedOperationException ex) {
+            purged = false;
+        }
         usb.write("bcd".getBytes());
         Thread.sleep(50);
         while(data.length()==0 || data.charAt(data.length()-1)!='d')
@@ -984,7 +990,8 @@ public class DeviceTest {
         telnet.setParameters(19200, 8, 1, UsbSerialPort.PARITY_NONE);
         telnet.write("x".getBytes());
         Thread.sleep(10); // ~ 20 bytes
-        purged = usb.serialPort.purgeHwBuffers(false, true);
+        if(purged)
+            usb.serialPort.purgeHwBuffers(false, true);
         Log.d(TAG, "purged = " + purged);
         telnet.write("y".getBytes());
         Thread.sleep(10); // ~ 20 bytes
@@ -1299,6 +1306,9 @@ public class DeviceTest {
             inputLinesSupported = true;
             inputLinesConnected = true;
         }
+        Boolean inputLineFalse = inputLinesSupported ? Boolean.FALSE : null;
+        Boolean inputLineTrue = inputLinesConnected ? Boolean.TRUE : inputLineFalse;
+
         EnumSet<UsbSerialPort.ControlLine> supportedControlLines = EnumSet.of(UsbSerialPort.ControlLine.RTS, UsbSerialPort.ControlLine.DTR);
         if(inputLinesSupported) {
             supportedControlLines.add(UsbSerialPort.ControlLine.CTS);
@@ -1331,12 +1341,12 @@ public class DeviceTest {
                         ? EnumSet.of(UsbSerialPort.ControlLine.RI)
                         : EnumSet.noneOf(UsbSerialPort.ControlLine.class),
                 usb.serialPort.getControlLines());
-        assertFalse(usb.serialPort.getRTS());
+        assertThat(usb.getControlLine(usb.serialPort::getRTS), equalTo(Boolean.FALSE));
-        assertFalse(usb.serialPort.getCTS());
+        assertThat(usb.getControlLine(usb.serialPort::getCTS), equalTo(inputLineFalse));
-        assertFalse(usb.serialPort.getDTR());
+        assertThat(usb.getControlLine(usb.serialPort::getDTR), equalTo(Boolean.FALSE));
-        assertFalse(usb.serialPort.getDSR());
+        assertThat(usb.getControlLine(usb.serialPort::getDSR), equalTo(inputLineFalse));
-        assertFalse(usb.serialPort.getCD());
+        assertThat(usb.getControlLine(usb.serialPort::getCD), equalTo(inputLineFalse));
-        assertEquals(usb.serialPort.getRI(), inputLinesConnected);
+        assertThat(usb.getControlLine(usb.serialPort::getRI), equalTo(inputLineTrue));
         telnet.write(data);
         if(usb.serialDriver instanceof CdcAcmSerialDriver)
             // arduino: control line feedback as serial_state notification is not implemented.
@@ -1354,12 +1364,12 @@ public class DeviceTest {
                         ? EnumSet.of(UsbSerialPort.ControlLine.RTS, UsbSerialPort.ControlLine.CTS)
                         : EnumSet.of(UsbSerialPort.ControlLine.RTS),
                 usb.serialPort.getControlLines());
-        assertTrue(usb.serialPort.getRTS());
+        assertThat(usb.getControlLine(usb.serialPort::getRTS), equalTo(Boolean.TRUE));
-        assertEquals(usb.serialPort.getCTS(), inputLinesConnected);
+        assertThat(usb.getControlLine(usb.serialPort::getCTS), equalTo(inputLineTrue));
-        assertFalse(usb.serialPort.getDTR());
+        assertThat(usb.getControlLine(usb.serialPort::getDTR), equalTo(Boolean.FALSE));
-        assertFalse(usb.serialPort.getDSR());
+        assertThat(usb.getControlLine(usb.serialPort::getDSR), equalTo(inputLineFalse));
-        assertFalse(usb.serialPort.getCD());
+        assertThat(usb.getControlLine(usb.serialPort::getCD), equalTo(inputLineFalse));
-        assertFalse(usb.serialPort.getRI());
+        assertThat(usb.getControlLine(usb.serialPort::getRI), equalTo(inputLineFalse));
         telnet.write(data);
         assertThat(Arrays.toString(data), usb.read(4), equalTo(data));
         usb.write(data);
@@ -1372,12 +1382,12 @@ public class DeviceTest {
                         ? EnumSet.of(UsbSerialPort.ControlLine.RTS, UsbSerialPort.ControlLine.DTR, UsbSerialPort.ControlLine.CD)
                         : EnumSet.of(UsbSerialPort.ControlLine.RTS, UsbSerialPort.ControlLine.DTR),
                 usb.serialPort.getControlLines());
-        assertTrue(usb.serialPort.getRTS());
+        assertThat(usb.getControlLine(usb.serialPort::getRTS), equalTo(Boolean.TRUE));
-        assertFalse(usb.serialPort.getCTS());
+        assertThat(usb.getControlLine(usb.serialPort::getCTS), equalTo(inputLineFalse));
-        assertTrue(usb.serialPort.getDTR());
+        assertThat(usb.getControlLine(usb.serialPort::getDTR), equalTo(Boolean.TRUE));
-        assertFalse(usb.serialPort.getDSR());
+        assertThat(usb.getControlLine(usb.serialPort::getDSR), equalTo(inputLineFalse));
-        assertEquals(usb.serialPort.getCD(), inputLinesConnected);
+        assertThat(usb.getControlLine(usb.serialPort::getCD), equalTo(inputLineTrue));
-        assertFalse(usb.serialPort.getRI());
+        assertThat(usb.getControlLine(usb.serialPort::getRI), equalTo(inputLineFalse));
         telnet.write(data);
         assertThat(Arrays.toString(data), usb.read(4), equalTo(data));
         usb.write(data);
@@ -1390,12 +1400,12 @@ public class DeviceTest {
                         ? EnumSet.of(UsbSerialPort.ControlLine.DTR, UsbSerialPort.ControlLine.DSR)
                         : EnumSet.of(UsbSerialPort.ControlLine.DTR),
                 usb.serialPort.getControlLines());
-        assertFalse(usb.serialPort.getRTS());
+        assertThat(usb.getControlLine(usb.serialPort::getRTS), equalTo(Boolean.FALSE));
-        assertFalse(usb.serialPort.getCTS());
+        assertThat(usb.getControlLine(usb.serialPort::getCTS), equalTo(inputLineFalse));
-        assertTrue(usb.serialPort.getDTR());
+        assertThat(usb.getControlLine(usb.serialPort::getDTR), equalTo(Boolean.TRUE));
-        assertEquals(usb.serialPort.getDSR(), inputLinesConnected);
+        assertThat(usb.getControlLine(usb.serialPort::getDSR), equalTo(inputLineTrue));
-        assertFalse(usb.serialPort.getCD());
+        assertThat(usb.getControlLine(usb.serialPort::getCD), equalTo(inputLineFalse));
-        assertFalse(usb.serialPort.getRI());
+        assertThat(usb.getControlLine(usb.serialPort::getRI), equalTo(inputLineFalse));
         telnet.write(data);
         assertThat(Arrays.toString(data), usb.read(4), equalTo(data));
         usb.write(data);
@@ -1412,12 +1422,12 @@ public class DeviceTest {
         if(outputRetained) retainedControlLines.add(UsbSerialPort.ControlLine.DTR);
         if(inputRetained)  retainedControlLines.add(UsbSerialPort.ControlLine.DSR);
         assertEquals(retainedControlLines, usb.serialPort.getControlLines());
-        assertFalse(usb.serialPort.getRTS());
+        assertThat(usb.getControlLine(usb.serialPort::getRTS), equalTo(Boolean.FALSE));
-        assertFalse(usb.serialPort.getCTS());
+        assertThat(usb.getControlLine(usb.serialPort::getCTS), equalTo(inputLineFalse));
-        assertEquals(usb.serialPort.getDTR(), outputRetained);
+        assertThat(usb.getControlLine(usb.serialPort::getDTR), equalTo(outputRetained));
-        assertEquals(usb.serialPort.getDSR(), inputRetained);
+        assertThat(usb.getControlLine(usb.serialPort::getDSR), equalTo(inputRetained ? inputLineTrue : inputLineFalse));
-        assertFalse(usb.serialPort.getCD());
+        assertThat(usb.getControlLine(usb.serialPort::getCD), equalTo(inputLineFalse));
-        assertFalse(usb.serialPort.getRI());
+        assertThat(usb.getControlLine(usb.serialPort::getRI), equalTo(inputLineFalse));
 
         usb.close(EnumSet.of(UsbWrapper.OpenCloseFlags.NO_CONTROL_LINE_INIT));
         usb.open(EnumSet.of(UsbWrapper.OpenCloseFlags.NO_CONTROL_LINE_INIT, UsbWrapper.OpenCloseFlags.NO_IOMANAGER_THREAD));
@@ -1436,28 +1446,35 @@ public class DeviceTest {
         // get... error
         try {
             usb.serialPort.getRI();
-            if (!inputLinesSupported)
+            if (usb.serialDriver instanceof ProlificSerialDriver)
-                ;
-            else if (usb.serialDriver instanceof ProlificSerialDriver)
                 ; // todo: currently not possible to detect, as bulkTransfer in background thread does not distinguish timeout and error
             else
                 fail("error expected");
         } catch (IOException ignored) {
+        } catch (UnsupportedOperationException ignored) {
         }
     }
 
     @Test
     public void deviceConnection() throws Exception {
-        byte buf[] = new byte[256];
+        byte[] buf = new byte[256];
         usb.open(EnumSet.of(UsbWrapper.OpenCloseFlags.NO_IOMANAGER_THREAD));
         usb.setParameters(115200, 8, 1, UsbSerialPort.PARITY_NONE);
 
         usb.write("x".getBytes());
         usb.serialPort.read(buf, 1000);
         usb.serialPort.setRTS(true);
+        try {
             usb.serialPort.getRI();
-        boolean purged = usb.serialPort.purgeHwBuffers(true, true);
+        } catch (UnsupportedOperationException ignored) {
-
+        }
+        boolean purged;
+        try {
+            usb.serialPort.purgeHwBuffers(true, true);
+            purged = true;
+        } catch (UnsupportedOperationException ex) {
+            purged = false;
+        }
         usb.deviceConnection.close();
         try {
             usb.setParameters(115200, 8, 1, UsbSerialPort.PARITY_NONE);
@@ -1481,13 +1498,12 @@ public class DeviceTest {
             fail("setRts error expected");
         } catch (IOException ignored) {
         }
-        if(usb.serialPort.getSupportedControlLines().contains(UsbSerialPort.ControlLine.RI) ) {
         try {
             usb.serialPort.getRI();
             if(!(usb.serialDriver instanceof ProlificSerialDriver))
                 fail("getRI error expected");
         } catch (IOException ignored) {
-            }
+        } catch (UnsupportedOperationException ignored) {
         }
         if(purged) {
             try {

usbSerialForAndroid/src/androidTest/java/com/hoho/android/usbserial/util/UsbWrapper.java

@@ -20,6 +20,7 @@ import java.nio.ByteBuffer;
 import java.util.Deque;
 import java.util.EnumSet;
 import java.util.LinkedList;
+import java.util.concurrent.Callable;
 import java.util.concurrent.Executors;
 
 import static org.junit.Assert.assertEquals;
@@ -223,6 +224,15 @@ public class UsbWrapper implements SerialInputOutputManager.Listener {
             Thread.sleep(1);
     }
 
+    /* return TRUE/FALSE/null instead of true/false/<throw UnsupportedOperationException> */
+    public Boolean getControlLine(Callable<?> callable) throws Exception {
+        try {
+            return (Boolean)callable.call();
+        } catch (UnsupportedOperationException t) {
+            return null;
+        }
+    }
+
     @Override
     public void onNewData(byte[] data) {
         long now = System.currentTimeMillis();

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

@@ -239,21 +239,6 @@ public class CdcAcmSerialDriver implements UsbSerialDriver {
             sendAcmControlMessage(SET_LINE_CODING, 0, msg);
         }
 
-        @Override
-        public boolean getCD() throws IOException {
-            return false;  // TODO
-        }
-
-        @Override
-        public boolean getCTS() throws IOException {
-            return false;  // TODO
-        }
-
-        @Override
-        public boolean getDSR() throws IOException {
-            return false;  // TODO
-        }
-
         @Override
         public boolean getDTR() throws IOException {
             return mDtr;
@@ -265,11 +250,6 @@ public class CdcAcmSerialDriver implements UsbSerialDriver {
             setDtrRts();
         }
 
-        @Override
-        public boolean getRI() throws IOException {
-            return false;  // TODO
-        }
-
         @Override
         public boolean getRTS() throws IOException {
             return mRts;

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

@@ -212,28 +212,28 @@ public abstract class CommonUsbSerialPort implements UsbSerialPort {
     public abstract void setParameters(int baudRate, int dataBits, int stopBits, int parity) throws IOException;
 
     @Override
-    public abstract boolean getCD() throws IOException;
+    public boolean getCD() throws IOException { throw new UnsupportedOperationException(); }
 
     @Override
-    public abstract boolean getCTS() throws IOException;
+    public boolean getCTS() throws IOException { throw new UnsupportedOperationException(); }
 
     @Override
-    public abstract boolean getDSR() throws IOException;
+    public boolean getDSR() throws IOException { throw new UnsupportedOperationException(); }
 
     @Override
-    public abstract boolean getDTR() throws IOException;
+    public boolean getDTR() throws IOException { throw new UnsupportedOperationException(); }
 
     @Override
-    public abstract void setDTR(boolean value) throws IOException;
+    public void setDTR(boolean value) throws IOException { throw new UnsupportedOperationException(); }
 
     @Override
-    public abstract boolean getRI() throws IOException;
+    public boolean getRI() throws IOException { throw new UnsupportedOperationException(); }
 
     @Override
-    public abstract boolean getRTS() throws IOException;
+    public boolean getRTS() throws IOException { throw new UnsupportedOperationException(); }
 
     @Override
-    public abstract void setRTS(boolean value) throws IOException;
+    public void setRTS(boolean value) throws IOException { throw new UnsupportedOperationException(); }
 
     @Override
     public abstract EnumSet<ControlLine> getControlLines() throws IOException;
@@ -242,8 +242,8 @@ public abstract class CommonUsbSerialPort implements UsbSerialPort {
     public abstract EnumSet<ControlLine> getSupportedControlLines() throws IOException;
 
     @Override
-    public boolean purgeHwBuffers(boolean purgeWriteBuffers, boolean purgeReadBuffers) throws IOException {
+    public void purgeHwBuffers(boolean purgeWriteBuffers, boolean purgeReadBuffers) throws IOException {
-        return false;
+        throw new UnsupportedOperationException();
     }
 
 }

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

@@ -305,15 +305,13 @@ public class Cp21xxSerialDriver implements UsbSerialDriver {
 
         @Override
         // note: only working on some devices, on other devices ignored w/o error
-        public boolean purgeHwBuffers(boolean purgeWriteBuffers, boolean purgeReadBuffers) throws IOException {
+        public void purgeHwBuffers(boolean purgeWriteBuffers, boolean purgeReadBuffers) throws IOException {
             int value = (purgeReadBuffers ? FLUSH_READ_CODE : 0)
                     | (purgeWriteBuffers ? FLUSH_WRITE_CODE : 0);
 
             if (value != 0) {
                 setConfigSingle(SILABSER_FLUSH_REQUEST_CODE, value);
             }
-
-            return true;
         }
 
     }

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

@@ -337,7 +337,7 @@ public class FtdiSerialDriver implements UsbSerialDriver {
         }
 
         @Override
-        public boolean purgeHwBuffers(boolean purgeWriteBuffers, boolean purgeReadBuffers) throws IOException {
+        public void purgeHwBuffers(boolean purgeWriteBuffers, boolean purgeReadBuffers) throws IOException {
             if (purgeWriteBuffers) {
                 int result = mConnection.controlTransfer(REQTYPE_HOST_TO_DEVICE, RESET_REQUEST,
                         RESET_PURGE_RX, mPortNumber+1, null, 0, USB_WRITE_TIMEOUT_MILLIS);
@@ -353,7 +353,6 @@ public class FtdiSerialDriver implements UsbSerialDriver {
                     throw new IOException("purge read buffer failed: result=" + result);
                 }
             }
-            return true;
         }
 
         public void setLatencyTimer(int latencyTime) throws IOException {

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

@@ -464,7 +464,7 @@ public class ProlificSerialDriver implements UsbSerialDriver {
         }
 
         @Override
-        public boolean purgeHwBuffers(boolean purgeWriteBuffers, boolean purgeReadBuffers) throws IOException {
+        public void purgeHwBuffers(boolean purgeWriteBuffers, boolean purgeReadBuffers) throws IOException {
             if (purgeWriteBuffers) {
                 vendorOut(FLUSH_RX_REQUEST, 0, null);
             }
@@ -472,8 +472,6 @@ public class ProlificSerialDriver implements UsbSerialDriver {
             if (purgeReadBuffers) {
                 vendorOut(FLUSH_TX_REQUEST, 0, null);
             }
-
-            return true;
         }
     }
 

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

@@ -152,32 +152,36 @@ public interface UsbSerialPort extends Closeable {
     /**
      * Gets the CD (Carrier Detect) bit from the underlying UART.
      *
-     * @return the current state, or {@code false} if not supported.
+     * @return the current state
      * @throws IOException if an error occurred during reading
+     * @throws UnsupportedOperationException if not supported
      */
     public boolean getCD() throws IOException;
 
     /**
      * Gets the CTS (Clear To Send) bit from the underlying UART.
      *
-     * @return the current state, or {@code false} if not supported.
+     * @return the current state
      * @throws IOException if an error occurred during reading
+     * @throws UnsupportedOperationException if not supported
      */
     public boolean getCTS() throws IOException;
 
     /**
      * Gets the DSR (Data Set Ready) bit from the underlying UART.
      *
-     * @return the current state, or {@code false} if not supported.
+     * @return the current state
      * @throws IOException if an error occurred during reading
+     * @throws UnsupportedOperationException if not supported
      */
     public boolean getDSR() throws IOException;
 
     /**
      * Gets the DTR (Data Terminal Ready) bit from the underlying UART.
      *
-     * @return the current state, or {@code false} if not supported.
+     * @return the current state
      * @throws IOException if an error occurred during reading
+     * @throws UnsupportedOperationException if not supported
      */
     public boolean getDTR() throws IOException;
 
@@ -186,22 +190,25 @@ public interface UsbSerialPort extends Closeable {
      *
      * @param value the value to set
      * @throws IOException if an error occurred during writing
+     * @throws UnsupportedOperationException if not supported
      */
     public void setDTR(boolean value) throws IOException;
 
     /**
      * Gets the RI (Ring Indicator) bit from the underlying UART.
      *
-     * @return the current state, or {@code false} if not supported.
+     * @return the current state
      * @throws IOException if an error occurred during reading
+     * @throws UnsupportedOperationException if not supported
      */
     public boolean getRI() throws IOException;
 
     /**
      * Gets the RTS (Request To Send) bit from the underlying UART.
      *
-     * @return the current state, or {@code false} if not supported.
+     * @return the current state
      * @throws IOException if an error occurred during reading
+     * @throws UnsupportedOperationException if not supported
      */
     public boolean getRTS() throws IOException;
 
@@ -210,6 +217,7 @@ public interface UsbSerialPort extends Closeable {
      *
      * @param value the value to set
      * @throws IOException if an error occurred during writing
+     * @throws UnsupportedOperationException if not supported
      */
     public void setRTS(boolean value) throws IOException;
 
@@ -235,11 +243,10 @@ public interface UsbSerialPort extends Closeable {
      *
      * @param purgeWriteBuffers {@code true} to discard non-transmitted output data
      * @param purgeReadBuffers {@code true} to discard non-read input data
-     * @return {@code true} if the operation was successful, or
-     *         {@code false} if the operation is not supported by the driver or device
      * @throws IOException if an error occurred during flush
+     * @throws UnsupportedOperationException if not supported
      */
-    public boolean purgeHwBuffers(boolean purgeWriteBuffers, boolean purgeReadBuffers) throws IOException;
+    public void purgeHwBuffers(boolean purgeWriteBuffers, boolean purgeReadBuffers) throws IOException;
 
     /**
      * Returns the current state of the connection.