content: /*
   * Copyright (C) 2010 The Android Open Source Project
   *
   * Licensed under the Apache License, Version 2.0 (the "License");
   * you may not use this file except in compliance with the License.
   * You may obtain a copy of the License at
   *
   *      http://www.apache.org/licenses/LICENSE-2.0
   *
   * Unless required by applicable law or agreed to in writing, software
   * distributed under the License is distributed on an "AS IS" BASIS,
   * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
   * See the License for the specific language governing permissions and
   * limitations under the License.
   */
  
  package android.hardware.usb;
  
  import android.annotation.Nullable;
  import android.os.Parcel;
  import android.os.Parcelable;
  import com.android.internal.util.Preconditions;
  
  /**
   * A class representing an interface on a {@link UsbDevice}.
   * USB devices can have one or more interfaces, each one providing a different
   * piece of functionality, separate from the other interfaces.
   * An interface will have one or more {@link UsbEndpoint}s, which are the
   * channels by which the host transfers data with the device.
   *
   * <div class="special reference">
   * <h3>Developer Guides</h3>
   * <p>For more information about communicating with USB hardware, read the
   * <a href="{@docRoot}guide/topics/usb/index.html">USB</a> developer guide.</p>
   * </div>
   */
  public class UsbInterface implements Parcelable {
  
      private final int mId;
      private final int mAlternateSetting;
      private @Nullable final String mName;
      private final int mClass;
      private final int mSubclass;
      private final int mProtocol;
  
      /** All endpoints of this interface, only null during creation */
      private Parcelable[] mEndpoints;
  
      /**
       * UsbInterface should only be instantiated by UsbService implementation
       * @hide
       */
      public UsbInterface(int id, int alternateSetting, @Nullable String name,
              int Class, int subClass, int protocol) {
          mId = id;
          mAlternateSetting = alternateSetting;
          mName = name;
          mClass = Class;
          mSubclass = subClass;
          mProtocol = protocol;
      }
  
      /**
       * Returns the interface's bInterfaceNumber field.
       * This is an integer that along with the alternate setting uniquely identifies
       * the interface on the device.
       *
       * @return the interface's ID
       */
      public int getId() {
          return mId;
      }
  
      /**
       * Returns the interface's bAlternateSetting field.
       * This is an integer that along with the ID uniquely identifies
       * the interface on the device.
       * {@link UsbDeviceConnection#setInterface} can be used to switch between
       * two interfaces with the same ID but different alternate setting.
       *
       * @return the interface's alternate setting
       */
      public int getAlternateSetting() {
          return mAlternateSetting;
      }
  
      /**
       * Returns the interface's name.
       *
       * @return the interface's name, or {@code null} if the property could not be read
       */
      public @Nullable String getName() {
          return mName;
      }
  
      /**
       * Returns the interface's class field.
       * Some useful constants for USB classes can be found in {@link UsbConstants}
       *
       * @return the interface's class
       */
      public int getInterfaceClass() {
          return mClass;
      }
  
      /**
       * Returns the interface's subclass field.
       *
       * @return the interface's subclass
       */
      public int getInterfaceSubclass() {
          return mSubclass;
      }
  
      /**
       * Returns the interface's protocol field.
       *
       * @return the interface's protocol
       */
      public int getInterfaceProtocol() {
          return mProtocol;
      }
  
      /**
       * Returns the number of {@link android.hardware.usb.UsbEndpoint}s this interface contains.
       *
       * @return the number of endpoints
       */
      public int getEndpointCount() {
          return mEndpoints.length;
      }
  
      /**
       * Returns the {@link android.hardware.usb.UsbEndpoint} at the given index.
       *
       * @return the endpoint
       */
      public UsbEndpoint getEndpoint(int index) {
          return (UsbEndpoint)mEndpoints[index];
      }
  
      /**
       * Only used by UsbService implementation
       * @hide
       */
      public void setEndpoints(Parcelable[] endpoints) {
          mEndpoints = Preconditions.checkArrayElementsNotNull(endpoints, "endpoints");
      }
  
      @Override
      public String toString() {
          StringBuilder builder = new StringBuilder("UsbInterface[mId=" + mId +
                  ",mAlternateSetting=" + mAlternateSetting +
                  ",mName=" + mName + ",mClass=" + mClass +
                  ",mSubclass=" + mSubclass + ",mProtocol=" + mProtocol +
                  ",mEndpoints=[");
          for (int i = 0; i < mEndpoints.length; i++) {
              builder.append("\n");
              builder.append(mEndpoints[i].toString());
          }
          builder.append("]");
          return builder.toString();
      }
  
      public static final @android.annotation.NonNull Parcelable.Creator<UsbInterface> CREATOR =
          new Parcelable.Creator<UsbInterface>() {
          public UsbInterface createFromParcel(Parcel in) {
              int id = in.readInt();
              int alternateSetting = in.readInt();
              String name = in.readString();
              int Class = in.readInt();
              int subClass = in.readInt();
              int protocol = in.readInt();
              Parcelable[] endpoints = in.readParcelableArray(UsbEndpoint.class.getClassLoader());
              UsbInterface intf = new UsbInterface(id, alternateSetting, name, Class, subClass, protocol);
              intf.setEndpoints(endpoints);
              return intf;
          }
  
          public UsbInterface[] newArray(int size) {
              return new UsbInterface[size];
          }
      };
  
      public int describeContents() {
          return 0;
      }
  
      public void writeToParcel(Parcel parcel, int flags) {
          parcel.writeInt(mId);
          parcel.writeInt(mAlternateSetting);
          parcel.writeString(mName);
          parcel.writeInt(mClass);
          parcel.writeInt(mSubclass);
          parcel.writeInt(mProtocol);
          parcel.writeParcelableArray(mEndpoints, 0);
     }
  }
  