Java Long Number Create toLong(byte[] b)

Description

Converts the first eight bytes of b to a 64-bit signed integer.

License

Apache License

Parameter

Parameter	Description
b	the buffer to read from.

Return

the converted value.

Declaration

public static long toLong(byte[] b) 

Method Source Code

//package com.java2s;
/*//w ww.  j  a  va2s. c o m
 * $Id: Util.java 169 2011-03-03 18:45:00Z ahto.truu $
 *
 *
 *
 * Copyright 2008-2011 GuardTime AS
 *
 * This file is part of the GuardTime client SDK.
 *
 * 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.
 */

public class Main {
    /**
     * Converts the first eight bytes of {@code b} to a 64-bit signed integer.
     * <p>
     * Assumes network byte order (ordered from the most to the least
     * significant byte).
     *
     * @param b
     *            the buffer to read from.
     * @return the converted value.
     */
    public static long toLong(byte[] b) {
        return toLong(b, 0);
    }

    /**
     * Converts eight bytes of {@code b}, starting from {@code offset}, to a
     * 64-bit signed integer.
     * <p>
     * Assumes network byte order (ordered from the most to the least
     * significant byte).
     *
     * @param b
     *            the buffer to read from.
     * @param offset
     *            start offset in the buffer.
     * @return the converted value.
     */
    public static long toLong(byte[] b, int offset) {
        return ((long) toInt(b, offset) << 32) + (toInt(b, offset + 4) & 0xffffffffL);
    }

    /**
     * Converts the first four bytes of {@code b} to a 32-bit signed integer.
     * <p>
     * Assumes network byte order (ordered from the most to the least
     * significant byte).
     *
     * @param b
     *            the buffer to read from.
     * @return the converted value.
     */
    public static int toInt(byte[] b) {
        return toInt(b, 0);
    }

    /**
     * Converts four bytes of {@code b}, starting from {@code offset}, to a
     * 32-bit signed integer.
     * <p>
     * Assumes network byte order (ordered from the most to the least
     * significant byte).
     *
     * @param b
     *            the buffer to read from.
     * @param offset
     *            start offset in the buffer.
     * @return the converted value.
     */
    public static int toInt(byte[] b, int offset) {
        return (toShort(b, offset) << 16) + (toShort(b, offset + 2) & 0xffff);
    }

    /**
     * Converts the first two bytes of {@code b} to a 16-bit signed integer.
     * <p>
     * Assumes network byte order (ordered from the most to the least
     * significant byte).
     *
     * @param b
     *            the buffer to read from.
     * @return the converted value.
     */
    public static short toShort(byte[] b) {
        return toShort(b, 0);
    }

    /**
     * Converts two bytes of {@code b}, starting from {@code offset}, to a
     * 16-bit signed integer.
     * <p>
     * Assumes network byte order (ordered from the most to the least
     * significant byte).
     *
     * @param b
     *            the buffer to read from.
     * @param offset
     *            start offset in the buffer.
     * @return the converted value.
     */
    public static short toShort(byte[] b, int offset) {
        return (short) ((b[offset++] << 8) + (b[offset++] & 0xff));
    }
}

Related

1. toLong(byte[] arr)
2. toLong(byte[] array, int offset)
3. toLong(byte[] b)
4. toLong(byte[] b)
5. toLong(byte[] b)
6. toLong(byte[] b)
7. toLong(byte[] b)
8. toLong(byte[] b)
9. toLong(byte[] b, int off, boolean bigEndian)