| /* |
| * Copyright (C) 2018 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 com.google.android.startop.iorap; |
| |
| import android.os.Parcelable; |
| import android.os.Parcel; |
| |
| import android.annotation.NonNull; |
| |
| /** |
| * Uniquely identify an {@link com.google.android.startop.iorap.IIorap} method invocation, |
| * used for asynchronous callbacks by the server. <br /><br /> |
| * |
| * As all system server binder calls must be {@code oneway}, this means all invocations |
| * into {@link com.google.android.startop.iorap.IIorap} are non-blocking. The request ID |
| * exists to associate all calls with their respective callbacks in |
| * {@link com.google.android.startop.iorap.ITaskListener}. |
| * |
| * @see com.google.android.startop.iorap.IIorap |
| * |
| * @hide |
| */ |
| public class RequestId implements Parcelable { |
| |
| public final long requestId; |
| |
| private static Object mLock = new Object(); |
| private static long mNextRequestId = 0; |
| |
| /** |
| * Create a monotonically increasing request ID.<br /><br /> |
| * |
| * It is invalid to re-use the same request ID for multiple method calls on |
| * {@link com.google.android.startop.iorap.IIorap}; a new request ID must be created |
| * each time. |
| */ |
| @NonNull public static RequestId nextValueForSequence() { |
| long currentRequestId; |
| synchronized (mLock) { |
| currentRequestId = mNextRequestId; |
| ++mNextRequestId; |
| } |
| return new RequestId(currentRequestId); |
| } |
| |
| private RequestId(long requestId) { |
| this.requestId = requestId; |
| |
| checkConstructorArguments(); |
| } |
| |
| private void checkConstructorArguments() { |
| if (requestId < 0) { |
| throw new IllegalArgumentException("request id must be non-negative"); |
| } |
| } |
| |
| @Override |
| public String toString() { |
| return String.format("{requestId: %d}", requestId); |
| } |
| |
| @Override |
| public int hashCode() { |
| return Long.hashCode(requestId); |
| } |
| |
| @Override |
| public boolean equals(Object other) { |
| if (this == other) { |
| return true; |
| } else if (other instanceof RequestId) { |
| return equals((RequestId) other); |
| } |
| return false; |
| } |
| |
| private boolean equals(RequestId other) { |
| return requestId == other.requestId; |
| } |
| |
| |
| //<editor-fold desc="Binder boilerplate"> |
| @Override |
| public void writeToParcel(Parcel out, int flags) { |
| out.writeLong(requestId); |
| } |
| |
| private RequestId(Parcel in) { |
| requestId = in.readLong(); |
| |
| checkConstructorArguments(); |
| } |
| |
| @Override |
| public int describeContents() { |
| return 0; |
| } |
| |
| public static final Parcelable.Creator<RequestId> CREATOR |
| = new Parcelable.Creator<RequestId>() { |
| public RequestId createFromParcel(Parcel in) { |
| return new RequestId(in); |
| } |
| |
| public RequestId[] newArray(int size) { |
| return new RequestId[size]; |
| } |
| }; |
| //</editor-fold> |
| } |