Java tutorial
// --------------------------------------------------------------------------- // jWebSocket - Shared Objects Plug-In // Copyright (c) 2010 Alexander Schulze, Innotrade GmbH // --------------------------------------------------------------------------- // This program is free software; you can redistribute it and/or modify it // under the terms of the GNU Lesser General Public License as published by the // Free Software Foundation; either version 3 of the License, or (at your // option) any later version. // This program is distributed in the hope that it will be useful, but WITHOUT // ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or // FITNESS FOR A PARTICULAR PURPOSE. See the GNU Lesser General Public License for // more details. // You should have received a copy of the GNU Lesser General Public License along // with this program; if not, see <http://www.gnu.org/licenses/lgpl.html>. // --------------------------------------------------------------------------- package org.jwebsocket.plugins.sharedobjects; import java.util.Arrays; import java.util.Collection; import java.util.Iterator; import java.util.List; import javolution.util.FastList; import org.apache.log4j.Logger; import org.json.JSONException; import org.json.JSONStringer; import org.jwebsocket.api.WebSocketConnector; import org.jwebsocket.config.JWebSocketServerConstants; import org.jwebsocket.logging.Logging; import org.jwebsocket.kit.PlugInResponse; import org.jwebsocket.plugins.TokenPlugIn; import org.jwebsocket.token.Token; /** * Pending... * @author aschulze */ public class SharedObjectsPlugIn extends TokenPlugIn { private static Logger log = Logging.getLogger(SharedObjectsPlugIn.class); // if namespace is changed update client plug-in accordingly! private String NS_SHARED_OBJECTS = JWebSocketServerConstants.NS_BASE + ".plugins.sharedObjs"; private SharedObjects sharedObjects = new SharedObjects(); // if data types are changed update client plug-in accordingly! private List DATA_TYPES = new FastList( Arrays.asList(new String[] { "number", "string", "boolean", "object", "set", "list", "map", "table" })); /** * */ public SharedObjectsPlugIn() { // specify default name space this.setNamespace(NS_SHARED_OBJECTS); } private boolean isDataTypeValid(String aDataType, WebSocketConnector aConnector, Token aResponse) { boolean isValid = ((aDataType != null && DATA_TYPES.contains(aDataType))); if (!isValid) { aResponse.put("code", -1); aResponse.put("msg", "invalid datatype '" + aDataType + "'"); getServer().sendToken(aConnector, aResponse); } return isValid; } private boolean doesContain(String aID, WebSocketConnector aConnector, Token aResponse) { boolean isValid = ((aID != null && sharedObjects.contains(aID))); if (!isValid) { aResponse.put("code", -1); aResponse.put("msg", "object '" + aID + "' not found"); getServer().sendToken(aConnector, aResponse); } return isValid; } private boolean alreadyExists(String aID, WebSocketConnector aConnector, Token aResponse) { boolean isValid = ((aID != null && sharedObjects.contains(aID))); if (isValid) { aResponse.put("code", -1); aResponse.put("msg", "object '" + aID + "' already exists"); getServer().sendToken(aConnector, aResponse); } return isValid; } private Object string2Object(String aDataType, String aValue) { Object lRes = null; // number if (aDataType.equals("number")) { try { lRes = Double.parseDouble(aValue); } catch (NumberFormatException ex) { } // string } else if (aDataType.equals("string")) { lRes = aValue; } return lRes; } private String object2String(String aDataType, Object aObject) { // all supported objects should provide the toString() method return aObject.toString(); } @Override public void processToken(PlugInResponse aResponse, WebSocketConnector aConnector, Token aToken) { String lType = aToken.getType(); String lNS = aToken.getNS(); String lID = aToken.getString("id"); String lDataType = aToken.getString("datatype"); String lValue = aToken.getString("value"); if (lType != null && (lNS == null || lNS.equals(NS_SHARED_OBJECTS))) { Token lResponse = getServer().createResponse(aToken); // create if (lType.equals("create")) { if (log.isDebugEnabled()) { log.debug("Processing 'create'..."); } if (!isDataTypeValid(lDataType, aConnector, lResponse)) { return; } if (alreadyExists(lID, aConnector, lResponse)) { return; } sharedObjects.put(lID, string2Object(lDataType, lValue)); Token lBCT = new Token(lNS, "event"); lBCT.put("name", "created"); lBCT.put("id", lID); lBCT.put("datatype", lDataType); lBCT.put("value", lValue); getServer().broadcastToken(aConnector, lBCT); // destroy } else if (lType.equals("destroy")) { if (log.isDebugEnabled()) { log.debug("Processing 'destroy'..."); } if (!doesContain(lID, aConnector, lResponse)) { return; } sharedObjects.remove(lID); Token lBCT = new Token(lNS, "event"); lBCT.put("name", "destroyed"); lBCT.put("id", lID); getServer().broadcastToken(aConnector, lBCT); // get } else if (lType.equals("get")) { if (log.isDebugEnabled()) { log.debug("Processing 'get'..."); } if (!doesContain(lID, aConnector, lResponse)) { return; } Object lObj = sharedObjects.get(lID); lResponse.put("id", lID); lResponse.put("result", lObj.toString()); // put } else if (lType.equals("update")) { if (log.isDebugEnabled()) { log.debug("Processing 'update'..."); } if (!isDataTypeValid(lDataType, aConnector, lResponse)) { return; } sharedObjects.put(lID, string2Object(lDataType, lValue)); Token lBCT = new Token(lNS, "event"); lBCT.put("name", "updated"); lBCT.put("id", lID); lBCT.put("datatype", lDataType); lBCT.put("value", lValue); getServer().broadcastToken(aConnector, lBCT); // init } else if (lType.equals("init")) { if (log.isDebugEnabled()) { log.debug("Processing 'init'..."); } Token lBCT = new Token(lNS, "event"); lBCT.put("name", "init"); String lData = null; try { JSONStringer jsonStringer = new JSONStringer(); // start main object jsonStringer.object(); // iterate through all items (fields) of the token Iterator<String> lIterator = sharedObjects.getKeys().iterator(); while (lIterator.hasNext()) { String lKey = lIterator.next(); Object lVal = sharedObjects.get(lKey); if (lVal instanceof Collection) { jsonStringer.key(lKey).array(); for (Object item : (Collection) lVal) { jsonStringer.value(item); } jsonStringer.endArray(); } else { jsonStringer.key(lKey).value(lVal); } } // end main object jsonStringer.endObject(); lData = jsonStringer.toString(); } catch (JSONException ex) { log.error(ex.getClass().getSimpleName() + ": " + ex.getMessage()); } lBCT.put("value", lData); getServer().sendToken(aConnector, lBCT); } else { log.warn("Invalid command " + lType + " received..."); lResponse.put("code", -1); lResponse.put("msg", "invalid type '" + lType + "'"); } getServer().sendToken(aConnector, lResponse); } } }