Android Byte Array to Long Convert parseLong(byte[] b, int start, int end, int radix)

Here you can find the source of parseLong(byte[] b, int start, int end, int radix)

Description

Convert the bytes within the specified range of the given byte array into a signed long in the given radix .

License

Open Source License

Declaration

public static long parseLong(byte[] b, int start, int end, int radix)
        throws NumberFormatException 

Method Source Code

//package com.java2s;
/*//from w  w w .j  a v  a  2s.  c  o  m
 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS HEADER.
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 * Copyright 1997-2007 Sun Microsystems, Inc. All rights reserved.
 *
 * The contents of this file are subject to the terms of either the GNU
 * General Public License Version 2 only ("GPL") or the Common Development
 * and Distribution License("CDDL") (collectively, the "License").  You
 * may not use this file except in compliance with the License. You can obtain
 * a copy of the License at https://glassfish.dev.java.net/public/CDDL+GPL.html
 * or glassfish/bootstrap/legal/LICENSE.txt.  See the License for the specific
 * language governing permissions and limitations under the License.
 *
 * When distributing the software, include this License Header Notice in each
 * file and include the License file at glassfish/bootstrap/legal/LICENSE.txt.
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 * Header, with the fields enclosed by brackets [] replaced by your own
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import java.io.ByteArrayInputStream;

public class Main {
    /**
     * Convert the bytes within the specified range of the given byte 
     * array into a signed long in the given radix . The range extends 
     * from <code>start</code> till, but not including <code>end</code>. <p>
     *
     * Based on java.lang.Long.parseLong()
     */
    public static long parseLong(byte[] b, int start, int end, int radix)
            throws NumberFormatException {
        if (b == null)
            throw new NumberFormatException("null");

        long result = 0;
        boolean negative = false;
        int i = start;
        long limit;
        long multmin;
        int digit;

        if (end > start) {
            if (b[i] == '-') {
                negative = true;
                limit = Long.MIN_VALUE;
                i++;
            } else {
                limit = -Long.MAX_VALUE;
            }
            multmin = limit / radix;
            if (i < end) {
                digit = Character.digit((char) b[i++], radix);
                if (digit < 0) {
                    throw new NumberFormatException("illegal number: "
                            + toString(b, start, end));
                } else {
                    result = -digit;
                }
            }
            while (i < end) {
                // Accumulating negatively avoids surprises near MAX_VALUE
                digit = Character.digit((char) b[i++], radix);
                if (digit < 0) {
                    throw new NumberFormatException("illegal number");
                }
                if (result < multmin) {
                    throw new NumberFormatException("illegal number");
                }
                result *= radix;
                if (result < limit + digit) {
                    throw new NumberFormatException("illegal number");
                }
                result -= digit;
            }
        } else {
            throw new NumberFormatException("illegal number");
        }
        if (negative) {
            if (i > start + 1) {
                return result;
            } else { /* Only got "-" */
                throw new NumberFormatException("illegal number");
            }
        } else {
            return -result;
        }
    }

    /**
     * Convert the bytes within the specified range of the given byte 
     * array into a signed long . The range extends from 
     * <code>start</code> till, but not including <code>end</code>. <p>
     */
    public static long parseLong(byte[] b, int start, int end)
            throws NumberFormatException {
        return parseLong(b, start, end, 10);
    }

    /**
     * Convert the bytes within the specified range of the given byte 
     * array into a String. The range extends from <code>start</code>
     * till, but not including <code>end</code>. <p>
     */
    public static String toString(byte[] b, int start, int end) {
        int size = end - start;
        char[] theChars = new char[size];

        for (int i = 0, j = start; i < size;)
            theChars[i++] = (char) (b[j++] & 0xff);

        return new String(theChars);
    }

    public static String toString(ByteArrayInputStream is) {
        int size = is.available();
        char[] theChars = new char[size];
        byte[] bytes = new byte[size];

        is.read(bytes, 0, size);
        for (int i = 0; i < size;)
            theChars[i] = (char) (bytes[i++] & 0xff);

        return new String(theChars);
    }
}

Related

  1. swap64bitFromArray(byte[] value, int offset)
  2. toLong(byte[] in)
  3. parseLong(byte[] b, int start, int end)
  4. bytes2long(byte[] b)
  5. byteArrayToLong(byte[] arr)
  6. byteArrayToLong(byte[] b)