com.android.ddmlib.utils.ArrayHelper Maven / Gradle / Ivy

Go to download
Show more of this group Show more artifacts with this name
Show all versions of ddmlib Show documentation
Library providing APIs to talk to Android devices
There is a newer version: 25.3.0
/*
 * Copyright (C) 2007 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.android.ddmlib.utils;

/**
 * Utility class providing array to int/long conversion for data received from devices through adb. 
 */
public final class ArrayHelper {

    /**
     * Swaps an unsigned value around, and puts the result in an array that can be sent to a device.
     * @param value The value to swap.
     * @param dest the destination array
     * @param offset the offset in the array where to put the swapped value.
     *      Array length must be at least offset + 4
     */
    public static void swap32bitsToArray(int value, byte[] dest, int offset) {
        dest[offset] = (byte)(value & 0x000000FF);
        dest[offset + 1] = (byte)((value & 0x0000FF00) >> 8);
        dest[offset + 2] = (byte)((value & 0x00FF0000) >> 16);
        dest[offset + 3] = (byte)((value & 0xFF000000) >> 24);
    }

    /**
     * Reads a signed 32 bit integer from an array coming from a device.
     * @param value the array containing the int
     * @param offset the offset in the array at which the int starts
     * @return the integer read from the array
     */
    public static int swap32bitFromArray(byte[] value, int offset) {
        int v = 0;
        v |= ((int)value[offset]) & 0x000000FF;
        v |= (((int)value[offset + 1]) & 0x000000FF) << 8;
        v |= (((int)value[offset + 2]) & 0x000000FF) << 16;
        v |= (((int)value[offset + 3]) & 0x000000FF) << 24;

        return v;
    }
    
    /**
     * Reads an unsigned 16 bit integer from an array coming from a device,
     * and returns it as an 'int'
     * @param value the array containing the 16 bit int (2 byte).
     * @param offset the offset in the array at which the int starts
     *      Array length must be at least offset + 2
     * @return the integer read from the array.
     */
    public static int swapU16bitFromArray(byte[] value, int offset) {
        int v = 0;
        v |= ((int)value[offset]) & 0x000000FF;
        v |= (((int)value[offset + 1]) & 0x000000FF) << 8;

        return v;
    }
    
    /**
     * Reads a signed 64 bit integer from an array coming from a device.
     * @param value the array containing the int
     * @param offset the offset in the array at which the int starts
     *      Array length must be at least offset + 8
     * @return the integer read from the array
     */
    public static long swap64bitFromArray(byte[] value, int offset) {
        long v = 0;
        v |= ((long)value[offset]) & 0x00000000000000FFL;
        v |= (((long)value[offset + 1]) & 0x00000000000000FFL) << 8;
        v |= (((long)value[offset + 2]) & 0x00000000000000FFL) << 16;
        v |= (((long)value[offset + 3]) & 0x00000000000000FFL) << 24;
        v |= (((long)value[offset + 4]) & 0x00000000000000FFL) << 32;
        v |= (((long)value[offset + 5]) & 0x00000000000000FFL) << 40;
        v |= (((long)value[offset + 6]) & 0x00000000000000FFL) << 48;
        v |= (((long)value[offset + 7]) & 0x00000000000000FFL) << 56;

        return v;
    }
}