asynchronous example problem
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mtfs...@gmail.com
Oct 6, 2015, 11:39:33 PM10/6/15
to usb4java
This is this program error message, how to solve ?? Thank You!
Exception in thread "main" org.usb4java.LibUsbException: USB error 5: Unable to submit transfer: Entity not found
at USB.usb5.write(usb5.java:124)
at USB.usb5.main(usb5.java:250)
Sending 24 bytes to device
-----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------
import java.nio.ByteBuffer;
import java.nio.ByteOrder;
import org.usb4java.BufferUtils;
import org.usb4java.DeviceHandle;
import org.usb4java.LibUsb;
import org.usb4java.LibUsbException;
import org.usb4java.Transfer;
import org.usb4java.TransferCallback;
/**
* Demonstrates how to do asynchronous bulk transfers. This demo sends some
* hardcoded data to an Android Device (Samsung Galaxy Nexus) and receives some
* data from it.
*
* If you have a different Android device then you can get this demo working by
* changing the vendor/product id, the interface number and the endpoint
* addresses.
*
* In this example the event handling is done with a thread which calls the
* {@link LibUsb#handleEventsTimeout(org.usb4java.Context, long)} method in a
* loop. You could also run this command inside the main application loop if
* there is one.
*
* @author Klaus Reimer <k...@ailis.de>
*/
public class usb5
{
/**
* This is the event handling thread. libusb doesn't start threads by its
* own so it is our own responsibility to give libusb time to handle the
* events in our own thread.
*/
static class EventHandlingThread extends Thread
{
/** If thread should abort. */
private volatile boolean abort;
/**
* Aborts the event handling thread.
*/
public void abort()
{
this.abort = true;
}
@Override
public void run()
{
while (!this.abort)
{
// Let libusb handle pending events. This blocks until events
// have been handled, a hotplug callback has been deregistered
// or the specified time of 0.5 seconds (Specified in
// Microseconds) has passed.
int result = LibUsb.handleEventsTimeout(null, 500000);
if (result != LibUsb.SUCCESS)
throw new LibUsbException("Unable to handle events", result);
}
}
}
/** Bytes for a CONNECT ADB message header. */
static final byte[] CONNECT_HEADER = new byte[] { 0x43, 0x4E, 0x58,
0x4E, 0x00, 0x00, 0x00, 0x01, 0x00, 0x10, 0x00, 0x00, 0x17, 0x00, 0x00,
0x00, 0x42, 0x06, 0x00, 0x00, (byte) 0xBC, (byte) 0xB1, (byte) 0xA7,
(byte) 0xB1 };
/** Bytes for a CONNECT ADB message body. */
static final byte[] CONNECT_BODY = new byte[] { 0x68, 0x6F, 0x73,
0x74, 0x3A, 0x31, 0x32, 0x33, 0x34, 0x35, 0x36, 0x37, 0x38, 0x3A, 0x41,
0x44, 0x42, 0x20, 0x44, 0x65, 0x6D, 0x6F, 0x00 };
/** The vendor ID of the Samsung Galaxy Nexus. */
private static final short VENDOR_ID = 0x096e;
/** The vendor ID of the Samsung Galaxy Nexus. */
private static final short PRODUCT_ID = 0x0201;
/** The ADB interface number of the Samsung Galaxy Nexus. */
private static final byte INTERFACE = 0;
/** The ADB input endpoint of the Samsung Galaxy Nexus. */
private static final byte IN_ENDPOINT = (byte) 0;
/** The ADB output endpoint of the Samsung Galaxy Nexus. */
private static final byte OUT_ENDPOINT = 0;
/** The communication timeout in milliseconds. */
private static final int TIMEOUT = 5000;
/**
* Flag set during the asynchronous transfers to indicate the program is
* finished.
*/
static volatile boolean exit = false;
/**
* Asynchronously writes some data to the device.
*
* @param handle
* The device handle.
* @param data
* The data to send to the device.
* @param callback
* The callback to execute when data has been transfered.
*/
public static void write(DeviceHandle handle, byte[] data,
TransferCallback callback)
{
ByteBuffer buffer = BufferUtils.allocateByteBuffer(data.length);
buffer.put(data);
Transfer transfer = LibUsb.allocTransfer();
LibUsb.fillBulkTransfer(transfer, handle, OUT_ENDPOINT, buffer,
callback, null, TIMEOUT);
System.out.println("Sending " + data.length + " bytes to device");
int result = LibUsb.submitTransfer(transfer);
if (result != LibUsb.SUCCESS)
{
throw new LibUsbException("Unable to submit transfer", result);
}
}
/**
* Asynchronously reads some data from the device.
*
* @param handle
* The device handle.
* @param size
* The number of bytes to read from the device.
* @param callback
* The callback to execute when data has been received.
*/
public static void read(DeviceHandle handle, int size,
TransferCallback callback)
{
ByteBuffer buffer = BufferUtils.allocateByteBuffer(size).order(
ByteOrder.LITTLE_ENDIAN);
Transfer transfer = LibUsb.allocTransfer();
LibUsb.fillBulkTransfer(transfer, handle, IN_ENDPOINT, buffer,
callback, null, TIMEOUT);
System.out.println("Reading " + size + " bytes from device");
int result = LibUsb.submitTransfer(transfer);
if (result != LibUsb.SUCCESS)
{
throw new LibUsbException("Unable to submit transfer", result);
}
}
/**
* Main method.
*
* @param args
* Command-line arguments (Ignored)
* @throws Exception
* When something goes wrong.
*/
public static void main(String[] args) throws Exception
{
// Initialize the libusb context
int result = LibUsb.init(null);
if (result != LibUsb.SUCCESS)
{
throw new LibUsbException("Unable to initialize libusb", result);
}
// Open test device
final DeviceHandle handle = LibUsb.openDeviceWithVidPid(null,
VENDOR_ID, PRODUCT_ID);
if (handle == null)
{
System.err.println("Test device not found.");
System.exit(1);
}
// Start event handling thread
EventHandlingThread thread = new EventHandlingThread();
thread.start();
// Claim the ADB interface
result = LibUsb.claimInterface(handle, INTERFACE);
if (result != LibUsb.SUCCESS)
{
throw new LibUsbException("Unable to claim interface", result);
}
// This callback is called after the ADB answer body has been
// received. The asynchronous transfer chain ends here.
final TransferCallback bodyReceived = new TransferCallback()
{
@Override
public void processTransfer(Transfer transfer)
{
System.out.println(transfer.actualLength() + " bytes received");
LibUsb.freeTransfer(transfer);
System.out.println("Asynchronous communication finished");
exit = true;
}
};
// This callback is called after the ADB answer header has been
// received and reads the ADB answer body
final TransferCallback headerReceived = new TransferCallback()
{
@Override
public void processTransfer(Transfer transfer)
{
System.out.println(transfer.actualLength() + " bytes received");
ByteBuffer header = transfer.buffer();
header.position(12);
int dataSize = header.asIntBuffer().get();
read(handle, dataSize, bodyReceived);
LibUsb.freeTransfer(transfer);
}
};
// This callback is called after the ADB CONNECT message body is sent
// and starts reads the ADB answer header.
final TransferCallback bodySent = new TransferCallback()
{
@Override
public void processTransfer(Transfer transfer)
{
System.out.println(transfer.actualLength() + " bytes received");
read(handle, 24, headerReceived);
// write(handle, CONNECT_BODY, receiveHeader);
LibUsb.freeTransfer(transfer);
}
};
// This callback is called after the ADB CONNECT message header is
// sent and sends the ADB CONNECT message body.
final TransferCallback headerSent = new TransferCallback()
{
@Override
public void processTransfer(Transfer transfer)
{
System.out.println(transfer.actualLength() + " bytes sent");
write(handle, CONNECT_BODY, bodySent);
LibUsb.freeTransfer(transfer);
}
};
// Send ADB CONNECT message header asynchronously. The rest of the
// communication is handled by the callbacks defined above.
write(handle, CONNECT_HEADER, headerSent);
// Fake application loop
while (!exit)
{
Thread.yield();
}
// Release the ADB interface
result = LibUsb.releaseInterface(handle, INTERFACE);
if (result != LibUsb.SUCCESS)
{
throw new LibUsbException("Unable to release interface", result);
}
// Close the device
LibUsb.close(handle);
// Stop event handling thread
thread.abort();
thread.join();
// Deinitialize the libusb context
LibUsb.exit(null);
System.out.println("Program finished");
}
}
mtfs...@gmail.com
Oct 7, 2015, 3:50:15 AM10/7/15
to usb4java
OR who know how to using java connect printer ??TQ^
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