Java tutorial
/** * Copyright (c) 2010-2017 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.homematic.internal.communicator.message; import java.io.EOFException; import java.io.IOException; import java.io.InputStream; import java.io.UnsupportedEncodingException; import java.math.BigDecimal; import java.math.BigInteger; import java.math.RoundingMode; import java.text.ParseException; import java.util.ArrayList; import java.util.Arrays; import java.util.Collection; import java.util.Collections; import java.util.Date; import java.util.List; import java.util.Map; import java.util.TreeMap; import org.apache.commons.io.IOUtils; import org.apache.commons.lang.ArrayUtils; import org.slf4j.Logger; import org.slf4j.LoggerFactory; /** * Handles BIN-RPC request and response messages to communicate with a Homematic gateway. * * @author Gerhard Riegler - Initial contribution */ public class BinRpcMessage implements RpcRequest<byte[]>, RpcResponse { private final Logger logger = LoggerFactory.getLogger(BinRpcMessage.class); public enum TYPE { REQUEST, RESPONSE; } private Object[] messageData; private byte binRpcData[]; private int offset; private String methodName; private TYPE type; private int args; private String encoding; public BinRpcMessage(String methodName, String encoding) { this(methodName, TYPE.REQUEST, encoding); } /** * Creates a new request with the specified methodName. */ public BinRpcMessage(String methodName, TYPE type, String encoding) { this.methodName = methodName; this.type = type; this.encoding = encoding; createHeader(); } /** * Decodes a BIN-RPC message from the given InputStream. */ public BinRpcMessage(InputStream is, boolean methodHeader, String encoding) throws IOException { this.encoding = encoding; byte sig[] = new byte[8]; int length = is.read(sig, 0, 4); if (length != 4) { throw new EOFException("Only " + length + " bytes received reading signature"); } validateBinXSignature(sig); length = is.read(sig, 4, 4); if (length != 4) { throw new EOFException("Only " + length + " bytes received reading message length"); } int datasize = (new BigInteger(ArrayUtils.subarray(sig, 4, 8))).intValue(); byte[] message = ArrayUtils.addAll(sig, IOUtils.toByteArray(is, datasize)); decodeMessage(message, methodHeader); } private void validateBinXSignature(byte[] sig) throws UnsupportedEncodingException { if (sig[0] != 'B' || sig[1] != 'i' || sig[2] != 'n') { throw new UnsupportedEncodingException("No BinX signature"); } } /** * Decodes a BIN-RPC message from the given byte array. */ public BinRpcMessage(byte[] message, boolean methodHeader, String encoding) throws IOException, ParseException { this.encoding = encoding; if (message.length < 8) { throw new EOFException("Only " + message.length + " bytes received"); } validateBinXSignature(message); decodeMessage(message, methodHeader); } private void decodeMessage(byte[] message, boolean methodHeader) throws IOException { binRpcData = message; offset = 8; if (methodHeader) { methodName = readString(); readInt(); } generateResponseData(); } public void setType(TYPE type) { binRpcData[3] = type == TYPE.RESPONSE ? (byte) 1 : (byte) 0; } private void generateResponseData() throws IOException { offset = 8 + (methodName != null ? methodName.length() + 8 : 0); List<Object> values = new ArrayList<Object>(); while (offset < binRpcData.length) { values.add(readRpcValue()); } messageData = values.toArray(); values.clear(); } private void createHeader() { binRpcData = new byte[256]; addString("Bin "); setType(type); addInt(0); // placeholder content length if (methodName != null) { addInt(methodName.length()); addString(methodName); addInt(0); // placeholder arguments } setInt(4, offset - 8); } /** * Adds arguments to the method. */ @Override public void addArg(Object argument) { addObject(argument); setInt(4, offset - 8); if (methodName != null) { setInt(12 + methodName.length(), ++args); } } public int getArgCount() { return args; } @Override public String getMethodName() { return methodName; } /** * {@inheritDoc} */ @Override public byte[] createMessage() { trimBinRpcData(); return binRpcData; } private void trimBinRpcData() { byte[] trimmed = new byte[offset]; System.arraycopy(binRpcData, 0, trimmed, 0, offset); binRpcData = trimmed; } /** * {@inheritDoc} */ @Override public Object[] getResponseData() { return messageData; } // read rpc values private int readInt() { byte bi[] = new byte[4]; System.arraycopy(binRpcData, offset, bi, 0, 4); offset += 4; return (new BigInteger(bi)).intValue(); } private String readString() throws UnsupportedEncodingException { int len = readInt(); offset += len; return new String(binRpcData, offset - len, len, encoding); } private Object readRpcValue() throws IOException { int type = readInt(); switch (type) { case 1: return new Integer(readInt()); case 2: return binRpcData[offset++] != 0 ? Boolean.TRUE : Boolean.FALSE; case 3: return readString(); case 4: int mantissa = readInt(); int exponent = readInt(); BigDecimal bd = new BigDecimal((double) mantissa / (double) (1 << 30) * Math.pow(2, exponent)); return bd.setScale(6, RoundingMode.HALF_DOWN).doubleValue(); case 5: return new Date(readInt() * 1000); case 0x100: // Array int numElements = readInt(); Collection<Object> array = new ArrayList<Object>(); while (numElements-- > 0) { array.add(readRpcValue()); } return array.toArray(); case 0x101: // Struct numElements = readInt(); Map<String, Object> struct = new TreeMap<String, Object>(); while (numElements-- > 0) { String name = readString(); struct.put(name, readRpcValue()); } return struct; default: for (int i = 0; i < binRpcData.length; i++) { logger.info("{} {}", Integer.toHexString(binRpcData[i]), (char) binRpcData[i]); } throw new IOException("Unknown data type " + type); } } private void setInt(int position, int value) { int temp = offset; offset = position; addInt(value); offset = temp; } private void addByte(byte b) { if (offset == binRpcData.length) { byte newdata[] = new byte[binRpcData.length * 2]; System.arraycopy(binRpcData, 0, newdata, 0, binRpcData.length); binRpcData = newdata; } binRpcData[offset++] = b; } private void addInt(int value) { addByte((byte) (value >> 24)); addByte((byte) (value >> 16)); addByte((byte) (value >> 8)); addByte((byte) (value)); } private void addDouble(double value) { double tmp = Math.abs(value); int exp = 0; if (tmp != 0 && tmp < 0.5) { while (tmp < 0.5) { tmp *= 2; exp--; } } else { while (tmp >= 1) { tmp /= 2; exp++; } } if (value < 0) { tmp *= -1; } int mantissa = (int) Math.round(tmp * 0x40000000); addInt(mantissa); addInt(exp); } private void addString(String string) { byte sd[]; try { sd = string.getBytes(encoding); } catch (UnsupportedEncodingException use) { sd = string.getBytes(); } for (byte ch : sd) { addByte(ch); } } private void addList(Collection<?> collection) { for (Object object : collection) { addObject(object); } } private void addObject(Object object) { if (object.getClass() == String.class) { addInt(3); String string = (String) object; addInt(string.length()); addString(string); } else if (object.getClass() == Boolean.class) { addInt(2); addByte(((Boolean) object).booleanValue() ? (byte) 1 : (byte) 0); } else if (object.getClass() == Integer.class) { addInt(1); addInt(((Integer) object).intValue()); } else if (object.getClass() == Double.class) { addInt(4); addDouble(((Double) object).doubleValue()); } else if (object.getClass() == Float.class) { addInt(4); BigDecimal bd = new BigDecimal((Float) object); addDouble(bd.setScale(6, RoundingMode.HALF_DOWN).doubleValue()); } else if (object.getClass() == BigDecimal.class) { addInt(4); addDouble(((BigDecimal) object).setScale(6, RoundingMode.HALF_DOWN).doubleValue()); } else if (object.getClass() == BigInteger.class) { addInt(4); addDouble(((BigInteger) object).doubleValue()); } else if (object.getClass() == Date.class) { addInt(5); addInt((int) ((Date) object).getTime() / 1000); } else if (object instanceof List<?>) { Collection<?> list = (Collection<?>) object; addInt(0x100); addInt(list.size()); addList(list); } else if (object instanceof Map<?, ?>) { Map<?, ?> map = (Map<?, ?>) object; addInt(0x101); addInt(map.size()); for (Map.Entry<?, ?> entry : map.entrySet()) { String key = (String) entry.getKey(); addInt(key.length()); addString(key); addList(Collections.singleton(entry.getValue())); } } } public String toBinString() { return Arrays.toString(createMessage()); } @Override public String toString() { try { trimBinRpcData(); generateResponseData(); return RpcUtils.dumpRpcMessage(methodName, messageData); } catch (Exception e) { throw new RuntimeException(e.getMessage(), e); } } }