Java tutorial
/* * www.openamf.org * * Distributable under LGPL license. * See terms of license at gnu.org. */ package org.openamf.io; import java.io.DataInputStream; import java.io.IOException; import java.io.UTFDataFormatException; import java.util.*; import org.apache.commons.logging.Log; import org.apache.commons.logging.LogFactory; import org.openamf.AMFBody; import org.openamf.AMFMessage; import org.openamf.config.OpenAMFConfig; import org.openamf.util.XMLUtils; import flashgateway.io.ASObject; /** * AMF Deserializer * * @author Jason Calabrese <jasonc@missionvi.com> * @author Pat Maddox <pergesu@users.sourceforge.net> * @author Sylwester Lachiewicz <lachiewicz@plusnet.pl> * @version $Revision: 1.38 $, $Date: 2004/12/09 04:50:07 $ */ public class AMFDeserializer { private static Log log = LogFactory.getLog(AMFDeserializer.class); private List storedObjects = null; /** * The AMF input stream */ protected DataInputStream inputStream; /** * Number of headers in the packet */ protected int headerCount; /** * Content of the headers */ protected List headers = new ArrayList(); /** * Number of bodies */ protected int bodyCount; /** * Content of the bodies */ protected List bodies = new ArrayList(); /** * Object to store the deserialized data */ protected AMFMessage message = new AMFMessage(); /** * Deserialize message * * @param inputStream message input stream * @throws IOException */ public AMFDeserializer(DataInputStream inputStream) throws IOException { if (log.isInfoEnabled()) log.info("Deserializing Message, for more info turn on debug level"); // Save the input stream for this object this.inputStream = inputStream; // Read the binary header readHeaders(); if (log.isDebugEnabled()) log.debug("readHeader"); // Read the binary body readBodies(); if (log.isDebugEnabled()) log.debug("readBody"); } public AMFMessage getAMFMessage() { return message; } /** * Read message header * * @throws IOException */ protected void readHeaders() throws IOException { // version message.setVersion(inputStream.readUnsignedShort()); // Find total number of header elements headerCount = inputStream.readUnsignedShort(); if (log.isDebugEnabled()) log.debug("headerCount = " + headerCount); // Loop over all the header elements for (int i = 0; i < headerCount; i++) { // clear storedObjects - references are new for every header storedObjects = new ArrayList(); String key = inputStream.readUTF(); // Find the must understand flag boolean required = inputStream.readBoolean(); // Grab the length of the header element long length = inputStream.readInt(); // Grab the type of the element byte type = inputStream.readByte(); // Turn the element into real data Object value = readData(type); // Save the name/value into the headers array message.addHeader(key, required, value); } } /** * Read message body * * @throws IOException */ protected void readBodies() throws IOException { // Find the total number of body elements bodyCount = inputStream.readUnsignedShort(); if (log.isDebugEnabled()) log.debug("bodyCount = " + bodyCount); // Loop over all the body elements for (int i = 0; i < bodyCount; i++) { //clear storedObjects storedObjects = new ArrayList(); // The target method String method = inputStream.readUTF(); // The target that the client understands String target = inputStream.readUTF(); // Get the length of the body element long length = inputStream.readInt(); // Grab the type of the element byte type = inputStream.readByte(); if (log.isDebugEnabled()) log.debug("type = " + type); // Turn the argument elements into real data Object data = readData(type); // Add the body element to the body object message.addBody(method, target, data, type); } } /** * Reads custom class * * @return * @throws IOException */ protected Object readCustomClass() throws IOException { // Grab the explicit type - somehow it works String type = inputStream.readUTF(); if (log.isDebugEnabled()) log.debug("Reading Custom Class: " + type); String mappedJavaClass = OpenAMFConfig.getInstance().getJavaClassName(type); if (mappedJavaClass != null) { type = mappedJavaClass; } ASObject aso = new ASObject(type); // The rest of the bytes are an object without the 0x03 header return readObject(aso); } protected ASObject readObject() throws IOException { ASObject aso = new ASObject(); return readObject(aso); } /** * Reads an object and converts the binary data into an List * * @param aso * @return * @throws IOException */ protected ASObject readObject(ASObject aso) throws IOException { storeObject(aso); // Init the array if (log.isDebugEnabled()) log.debug("reading object"); // Grab the key String key = inputStream.readUTF(); for (byte type = inputStream.readByte(); type != 9; type = inputStream.readByte()) { // Grab the value Object value = readData(type); // Save the name/value pair in the map if (value == null) { log.info("Skipping NULL value for :" + key); } else { aso.put(key, value); if (log.isDebugEnabled()) log.debug(" adding {key=" + key + ", value=" + value + ", type=" + type + "}"); } // Get the next name key = inputStream.readUTF(); } if (log.isDebugEnabled()) log.debug("finished reading object"); // Return the map return aso; } /** * Reads array * * @return * @throws IOException */ protected List readArray() throws IOException { // Init the array List array = new ArrayList(); storeObject(array); if (log.isDebugEnabled()) log.debug("Reading array"); // Grab the length of the array long length = inputStream.readInt(); if (log.isDebugEnabled()) log.debug("array length = " + length); // Loop over all the elements in the data for (long i = 0; i < length; i++) { // Grab the type for each element byte type = inputStream.readByte(); // Grab the element Object data = readData(type); array.add(data); } // Return the data return array; } /** * Store object in internal array * * @param o */ private void storeObject(Object o) { storedObjects.add(o); if (log.isDebugEnabled()) log.debug("storedObjects.size: " + storedObjects.size()); } /** * Reads date * * @return * @throws IOException */ protected Date readDate() throws IOException { long ms = (long) inputStream.readDouble(); // Date in millis from 01/01/1970 // here we have to read in the raw // timezone offset (which comes in minutes, but incorrectly signed), // make it millis, and fix the sign. int timeoffset = inputStream.readShort() * 60000 * -1; // now we have millis TimeZone serverTimeZone = TimeZone.getDefault(); // now we subtract the current timezone offset and add the one that was passed // in (which is of the Flash client), which gives us the appropriate ms (i think) // -alon Calendar sent = new GregorianCalendar(); sent.setTime((new Date(ms - serverTimeZone.getRawOffset() + timeoffset))); TimeZone sentTimeZone = sent.getTimeZone(); // we have to handle daylight savings ms as well if (sentTimeZone.inDaylightTime(sent.getTime())) { // // Implementation note: we are trying to maintain compatibility // with J2SE 1.3.1 // // As such, we can't use java.util.Calendar.getDSTSavings() here // sent.setTime(new java.util.Date(sent.getTime().getTime() - 3600000)); } return sent.getTime(); } /** * Reads flushed stored object * * @return * @throws IOException */ protected Object readFlushedSO() throws IOException { int index = inputStream.readUnsignedShort(); if (log.isDebugEnabled()) log.debug("Object Index: " + index); return storedObjects.get(index); } /** * Reads object * * @return */ protected Object readASObject() { return null; } /** * Reads object from inputstream with selected type * * @param type * @return * @throws IOException */ protected Object readData(byte type) throws IOException { if (log.isDebugEnabled()) log.debug("Reading data of type " + AMFBody.getObjectTypeDescription(type)); switch (type) { case AMFBody.DATA_TYPE_NUMBER: // 0 return new Double(inputStream.readDouble()); case AMFBody.DATA_TYPE_BOOLEAN: // 1 return new Boolean(inputStream.readBoolean()); case AMFBody.DATA_TYPE_STRING: // 2 return inputStream.readUTF(); case AMFBody.DATA_TYPE_OBJECT: // 3 return readObject(); case AMFBody.DATA_TYPE_MOVIE_CLIP: // 4 throw new IOException("Unknown/unsupported object type " + AMFBody.getObjectTypeDescription(type)); case AMFBody.DATA_TYPE_NULL: // 5 case AMFBody.DATA_TYPE_UNDEFINED: //6 return null; case AMFBody.DATA_TYPE_REFERENCE_OBJECT: // 7 return readFlushedSO(); case AMFBody.DATA_TYPE_MIXED_ARRAY: // 8 long length = inputStream.readInt(); //don't do anything with the length return readObject(); case AMFBody.DATA_TYPE_OBJECT_END: // 9 return null; case AMFBody.DATA_TYPE_ARRAY: // 10 return readArray(); case AMFBody.DATA_TYPE_DATE: // 11 return readDate(); case AMFBody.DATA_TYPE_LONG_STRING: // 12 return readLongUTF(inputStream); case AMFBody.DATA_TYPE_AS_OBJECT: // 13 return readASObject(); case AMFBody.DATA_TYPE_RECORDSET: // 14 // TODO - fixme return null; case AMFBody.DATA_TYPE_XML: // 15 return XMLUtils.convertToDOM(inputStream); case AMFBody.DATA_TYPE_CUSTOM_CLASS: // 16 return readCustomClass(); default: throw new IOException("Unknown/unsupported object type " + AMFBody.getObjectTypeDescription(type)); } } /** * This is a hacked verison of Java's DataInputStream.readUTF(), which only * supports Strings <= 65535 UTF-8-encoded characters */ private Object readLongUTF(DataInputStream in) throws IOException { int utflen = in.readInt(); StringBuffer str = new StringBuffer(utflen); byte bytearr[] = new byte[utflen]; int c, char2, char3; int count = 0; in.readFully(bytearr, 0, utflen); while (count < utflen) { c = (int) bytearr[count] & 0xff; switch (c >> 4) { case 0: case 1: case 2: case 3: case 4: case 5: case 6: case 7: /* 0xxxxxxx*/ count++; str.append((char) c); break; case 12: case 13: /* 110x xxxx 10xx xxxx*/ count += 2; if (count > utflen) throw new UTFDataFormatException(); char2 = (int) bytearr[count - 1]; if ((char2 & 0xC0) != 0x80) throw new UTFDataFormatException(); str.append((char) (((c & 0x1F) << 6) | (char2 & 0x3F))); break; case 14: /* 1110 xxxx 10xx xxxx 10xx xxxx */ count += 3; if (count > utflen) throw new UTFDataFormatException(); char2 = (int) bytearr[count - 2]; char3 = (int) bytearr[count - 1]; if (((char2 & 0xC0) != 0x80) || ((char3 & 0xC0) != 0x80)) throw new UTFDataFormatException(); str.append((char) (((c & 0x0F) << 12) | ((char2 & 0x3F) << 6) | ((char3 & 0x3F) << 0))); break; default: /* 10xx xxxx, 1111 xxxx */ throw new UTFDataFormatException(); } } // The number of chars produced may be less than utflen return new String(str); } }