Java Integer From intFromBigEndainByteArray(byte[] buf, int offset, int len)

Description

utility to generate an int from an array of bytes in BigEndain order

License

Open Source License

Parameter

Parameter	Description
buf	byte array source
offset	into the array
len	number of bytes to use, must be 4 or less

Return

an int

Declaration

public static int intFromBigEndainByteArray(byte[] buf, int offset, int len) 

Method Source Code

//package com.java2s;
/**//from  w w  w. j  a  va  2s.  c  o m
 * static byte array utilities
 *
 * Copyright (c) 2004, Pat Farrell, All rights reserved.
 * 
 * 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. * 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 {
    /** utility to generate an int from an array of bytes in BigEndain order
     * @param buf byte array source
     * @param offset into the array
     * @param len number of bytes to use, must be 4 or less
     * @return an int
     */
    public static int intFromBigEndainByteArray(byte[] buf, int offset, int len) {
        return (int) longFromBigEndainArray(buf, offset, len);
    }

    /** 
     * utility to build a long from values in an array of bytes in bigEndian order
     * @param buf byte array source
     * @param offset offset into array
     * @param len number to read (must be  8 or less
     * @return a long
     */
    public static long longFromBigEndainArray(byte[] buf, int offset, int len) {
        long val = 0;
        for (int i = 0; i < len; i++) {
            val = val << 8;
            int d = (0xff & buf[i + offset]);
            val += d;
        }
        return val;
    }
}

Related

1. intFrom(byte a, byte b, byte c, byte d)
2. intFrom2Bytes(byte[] bytes, int index)
3. intFrom4Bytes(byte[] bytes, int index)
4. intFromBase64(String value)
5. intFromByte(byte byteValue)
6. intFromByteArray(final byte[] buf, final int offset)
7. intFromByteArray(final byte[] byteArray)
8. intFromByteRGB(byte[] reds, byte[] greens, byte[] blues)