| /* |
| * Copyright (c) 2009, 2011, Oracle and/or its affiliates. All rights reserved. |
| * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER. |
| * |
| * This code is free software; you can redistribute it and/or modify it |
| * under the terms of the GNU General Public License version 2 only, as |
| * published by the Free Software Foundation. |
| * |
| * This code is distributed in the hope that it will be useful, but WITHOUT |
| * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or |
| * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License |
| * version 2 for more details (a copy is included in the LICENSE file that |
| * accompanied this code). |
| * |
| * You should have received a copy of the GNU General Public License version |
| * 2 along with this work; if not, write to the Free Software Foundation, |
| * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA. |
| * |
| * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA |
| * or visit www.oracle.com if you need additional information or have any |
| * questions. |
| */ |
| package org.graalvm.compiler.bytecode; |
| |
| /** |
| * A collection of utility methods for dealing with bytes, particularly in byte arrays. |
| */ |
| public class Bytes { |
| |
| /** |
| * Gets a signed 1-byte value. |
| * |
| * @param data the array containing the data |
| * @param bci the start index of the value to retrieve |
| * @return the signed 1-byte value at index {@code bci} in array {@code data} |
| */ |
| public static int beS1(byte[] data, int bci) { |
| return data[bci]; |
| } |
| |
| /** |
| * Gets a signed 2-byte big-endian value. |
| * |
| * @param data the array containing the data |
| * @param bci the start index of the value to retrieve |
| * @return the signed 2-byte, big-endian, value at index {@code bci} in array {@code data} |
| */ |
| public static int beS2(byte[] data, int bci) { |
| return (data[bci] << 8) | (data[bci + 1] & 0xff); |
| } |
| |
| /** |
| * Gets an unsigned 1-byte value. |
| * |
| * @param data the array containing the data |
| * @param bci the start index of the value to retrieve |
| * @return the unsigned 1-byte value at index {@code bci} in array {@code data} |
| */ |
| public static int beU1(byte[] data, int bci) { |
| return data[bci] & 0xff; |
| } |
| |
| /** |
| * Gets an unsigned 2-byte big-endian value. |
| * |
| * @param data the array containing the data |
| * @param bci the start index of the value to retrieve |
| * @return the unsigned 2-byte, big-endian, value at index {@code bci} in array {@code data} |
| */ |
| public static int beU2(byte[] data, int bci) { |
| return ((data[bci] & 0xff) << 8) | (data[bci + 1] & 0xff); |
| } |
| |
| /** |
| * Gets a signed 4-byte big-endian value. |
| * |
| * @param data the array containing the data |
| * @param bci the start index of the value to retrieve |
| * @return the signed 4-byte, big-endian, value at index {@code bci} in array {@code data} |
| */ |
| public static int beS4(byte[] data, int bci) { |
| return (data[bci] << 24) | ((data[bci + 1] & 0xff) << 16) | ((data[bci + 2] & 0xff) << 8) | (data[bci + 3] & 0xff); |
| } |
| |
| /** |
| * Gets either a signed 2-byte or a signed 4-byte big-endian value. |
| * |
| * @param data the array containing the data |
| * @param bci the start index of the value to retrieve |
| * @param fourByte if true, this method will return a 4-byte value |
| * @return the signed 2 or 4-byte, big-endian, value at index {@code bci} in array {@code data} |
| */ |
| public static int beSVar(byte[] data, int bci, boolean fourByte) { |
| if (fourByte) { |
| return beS4(data, bci); |
| } else { |
| return beS2(data, bci); |
| } |
| } |
| } |