InsteonHubByteUtil.java

/**
 * Copyright (c) 2010-2016 by the respective copyright holders.
 *
 * All rights reserved. This program and the accompanying materials
 * are made available under the terms of the Eclipse Public License v1.0
 * which accompanies this distribution, and is available at
 * http://www.eclipse.org/legal/epl-v10.html
 */
package org.openhab.binding.insteonhub.internal.util;

import java.io.IOException;
import java.io.InputStream;
import java.util.Arrays;

import org.apache.commons.codec.binary.Hex;

/**
 * Utility functions for dealing with hex/buffers/bytes
 *
 * @author Eric Thill
 * @since 1.4.0
 */
public class InsteonHubByteUtil {

    public static int byteToUnsignedInt(byte b) {
        int i = b;
        if (i < 0) {
            i += 256;
        }
        return i;
    }

    public static String encodeDeviceHex(byte[] buf, int off) {
        byte[] devBuf = Arrays.copyOfRange(buf, off, off + 3);
        return Hex.encodeHexString(devBuf).replace(" ", "");
    }

    public static void fillBuffer(InputStream in, byte[] buf, int off) throws IOException {
        while (off < buf.length) {
            int numRead = in.read(buf, off, buf.length - off);
            if (numRead == -1) {
                throw new IOException("Unexpected end of stream");
            }
            off += numRead;
        }
    }

    public static byte readByte(InputStream in) throws IOException {
        int v = in.read();
        if (v == -1) {
            throw new IOException("Unexpected end of stream");
        }
        return (byte) v;
    }

    public static boolean checkBit(int value, int idx) {
        return (value & (1 << idx)) != 0;
    }
}