IT. Expert System.

Android Reference

UsbRequest


android.hardware.usb

Class UsbRequest

    • Constructor Detail

      • UsbRequest

        public UsbRequest()
    • Method Detail

      • initialize

        public boolean initialize(UsbDeviceConnection connection,
                         UsbEndpoint endpoint)
        Initializes the request so it can read or write data on the given endpoint. Whether the request allows reading or writing depends on the direction of the endpoint.
        Parameters:
        endpoint - the endpoint to be used for this request.
        Returns:
        true if the request was successfully opened.
      • close

        public void close()
        Releases all resources related to this request.
      • finalize

        protected void finalize()
                         throws Throwable
        Description copied from class: Object
        Invoked when the garbage collector has detected that this instance is no longer reachable. The default implementation does nothing, but this method can be overridden to free resources.

        Note that objects that override finalize are significantly more expensive than objects that don't. Finalizers may be run a long time after the object is no longer reachable, depending on memory pressure, so it's a bad idea to rely on them for cleanup. Note also that finalizers are run on a single VM-wide finalizer thread, so doing blocking work in a finalizer is a bad idea. A finalizer is usually only necessary for a class that has a native peer and needs to call a native method to destroy that peer. Even then, it's better to provide an explicit close method (and implement Closeable), and insist that callers manually dispose of instances. This works well for something like files, but less well for something like a BigInteger where typical calling code would have to deal with lots of temporaries. Unfortunately, code that creates lots of temporaries is the worst kind of code from the point of view of the single finalizer thread.

        If you must use finalizers, consider at least providing your own ReferenceQueue and having your own thread process that queue.

        Unlike constructors, finalizers are not automatically chained. You are responsible for calling super.finalize() yourself.

        Uncaught exceptions thrown by finalizers are ignored and do not terminate the finalizer thread. See Effective Java Item 7, "Avoid finalizers" for more.

        Overrides:
        finalize in class Object
        Throws:
        Throwable
      • getEndpoint

        public UsbEndpoint getEndpoint()
        Returns the endpoint for the request, or null if the request is not opened.
        Returns:
        the request's endpoint
      • queue

        public boolean queue(ByteBuffer buffer,
                    int length)
        Queues the request to send or receive data on its endpoint. For OUT endpoints, the given buffer data will be sent on the endpoint. For IN endpoints, the endpoint will attempt to read the given number of bytes into the specified buffer. If the queueing operation is successful, we return true and the result will be returned via UsbDeviceConnection.requestWait()
        Parameters:
        buffer - the buffer containing the bytes to write, or location to store the results of a read
        length - number of bytes to read or write
        Returns:
        true if the queueing operation succeeded
      • cancel

        public boolean cancel()
        Cancels a pending queue operation.
        Returns:
        true if cancelling succeeded


Content

Android Reference

Java basics

Java Enterprise Edition (EE)

Java Standard Edition (SE)

SQL

HTML

PHP

CSS

Java Script

MYSQL

JQUERY

VBS

REGEX

C

C++

C#

Design patterns

RFC (standard status)

RFC (proposed standard status)

RFC (draft standard status)

RFC (informational status)

RFC (experimental status)

RFC (best current practice status)

RFC (historic status)

RFC (unknown status)

IT dictionary

License.
All information of this service is derived from the free sources and is provided solely in the form of quotations. This service provides information and interfaces solely for the familiarization (not ownership) and under the "as is" condition.
Copyright 2016 © ELTASK.COM. All rights reserved.
Site is optimized for mobile devices.
Downloads: 251 / 158676099. Delta: 0.05923 с