Util.java

package com.laifeng.sopcastsdk.stream.sender.rtmp;

import java.io.IOException;
import java.io.InputStream;
import java.io.OutputStream;

/**
 * Misc utility method
 * @author francois
 */
public class Util {

    private static final String HEXES = "0123456789ABCDEF";

    public static void writeUnsignedInt32(OutputStream out, int value) throws IOException {
        out.write((byte) (value >>> 24));
        out.write((byte) (value >>> 16));
        out.write((byte) (value >>> 8));
        out.write((byte) value);
    }

    public static int readUnsignedInt32(InputStream in) throws IOException {
        return ((in.read() & 0xff) << 24) | ((in.read() & 0xff) << 16) | ((in.read() & 0xff) << 8) | (in.read() & 0xff);
    }

    public static int readUnsignedInt24(InputStream in) throws IOException {
        return ((in.read() & 0xff) << 16) | ((in.read() & 0xff) << 8) | (in.read() & 0xff);
    }

    public static int readUnsignedInt16(InputStream in) throws IOException {
        return ((in.read() & 0xff) << 8) | (in.read() & 0xff);
    }

    public static void writeUnsignedInt24(OutputStream out, int value) throws IOException {
        out.write((byte) (value >>> 16));
        out.write((byte) (value >>> 8));
        out.write((byte) value);
    }

    public static void writeUnsignedInt16(OutputStream out, int value) throws IOException {
        out.write((byte) (value >>> 8));
        out.write((byte) value);
    }

    public static int toUnsignedInt32(byte[] bytes) {
        return (((int) bytes[0] & 0xff) << 24) | (((int)bytes[1] & 0xff) << 16) | (((int)bytes[2] & 0xff) << 8) | ((int)bytes[3] & 0xff);
    }

    public static int toUnsignedInt32LittleEndian(byte[] bytes) {
        return ((bytes[3] & 0xff) << 24) | ((bytes[2] & 0xff) << 16) | ((bytes[1] & 0xff) << 8) | (bytes[0] & 0xff);
    }
    
    public static void writeUnsignedInt32LittleEndian(OutputStream out, int value) throws IOException {        
        out.write((byte) value);
        out.write((byte) (value >>> 8));
        out.write((byte) (value >>> 16));
        out.write((byte) (value >>> 24));
    }
    
    public static int toUnsignedInt24(byte[] bytes) {
        return ((bytes[1] & 0xff) << 16) | ((bytes[2] & 0xff) << 8) | (bytes[3] & 0xff);
    }

    public static int toUnsignedInt16(byte[] bytes) {
        return ((bytes[2] & 0xff) << 8) | (bytes[3] & 0xff);
    }

    public static String toHexString(byte[] raw) {
        if (raw == null) {
            return null;
        }
        final StringBuilder hex = new StringBuilder(2 * raw.length);
        for (final byte b : raw) {
            hex.append(HEXES.charAt((b & 0xF0) >> 4)).append(HEXES.charAt((b & 0x0F)));
        }
        return hex.toString();
    }
    
    public static String toHexString(byte b) {
        return new StringBuilder().append(HEXES.charAt((b & 0xF0) >> 4)).append(HEXES.charAt((b & 0x0F))).toString();        
    }

    /** 
     * Reads bytes from the specified inputstream into the specified target buffer until it is filled up     
     */
    public static void readBytesUntilFull(InputStream in, byte[] targetBuffer) throws IOException {
        int totalBytesRead = 0;
        int read;
        final int targetBytes = targetBuffer.length;
        do {
            read = in.read(targetBuffer, totalBytesRead, (targetBytes - totalBytesRead));
            if (read != -1) {
                totalBytesRead += read;
            } else {
                throw new IOException("Unexpected EOF reached before read buffer was filled");
            }
        } while (totalBytesRead < targetBytes);
    }    

    public static byte[] toByteArray(double d) {
        long l = Double.doubleToRawLongBits(d);
        return new byte[]{
                    (byte) ((l >> 56) & 0xff),
                    (byte) ((l >> 48) & 0xff),
                    (byte) ((l >> 40) & 0xff),
                    (byte) ((l >> 32) & 0xff),
                    (byte) ((l >> 24) & 0xff),
                    (byte) ((l >> 16) & 0xff),
                    (byte) ((l >> 8) & 0xff),
                    (byte) (l & 0xff),};
    }

    public static byte[] unsignedInt32ToByteArray(int value) throws IOException {
        return new byte[]{
                    (byte) (value >>> 24),
                    (byte) (value >>> 16),
                    (byte) (value >>> 8),
                    (byte) value};
    }

    public static double readDouble(InputStream in) throws IOException {
        long bits = ((long) (in.read() & 0xff) << 56) | ((long) (in.read() & 0xff) << 48) | ((long) (in.read() & 0xff) << 40) | ((long) (in.read() & 0xff) << 32) | ((in.read() & 0xff) << 24) | ((in.read() & 0xff) << 16) | ((in.read() & 0xff) << 8) | (in.read() & 0xff);
        return Double.longBitsToDouble(bits);
    }       

    public static void writeDouble(OutputStream out, double d) throws IOException {
        long l = Double.doubleToRawLongBits(d);
        out.write(new byte[]{
                    (byte) ((l >> 56) & 0xff),
                    (byte) ((l >> 48) & 0xff),
                    (byte) ((l >> 40) & 0xff),
                    (byte) ((l >> 32) & 0xff),
                    (byte) ((l >> 24) & 0xff),
                    (byte) ((l >> 16) & 0xff),
                    (byte) ((l >> 8) & 0xff),
                    (byte) (l & 0xff)});
    }
}