Java tutorial
package ch.unifr.pai.twice.multipointer.client; /* * Copyright 2013 Oliver Schmid * Licensed under the Apache License, Version 2.0 (the "License"); * you may not use this file except in compliance with the License. * You may obtain a copy of the License at * * http://www.apache.org/licenses/LICENSE-2.0 * * Unless required by applicable law or agreed to in writing, software * distributed under the License is distributed on an "AS IS" BASIS, * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. * See the License for the specific language governing permissions and * limitations under the License. */ import java.util.ArrayList; import java.util.HashMap; import java.util.HashSet; import java.util.List; import java.util.Map; import java.util.Set; import ch.unifr.pai.twice.multipointer.client.MouseCursorTimeoutEvent.Handler; import ch.unifr.pai.twice.utils.device.client.UUID; import com.google.gwt.core.client.GWT; import com.google.gwt.core.client.JavaScriptObject; import com.google.gwt.dom.client.Style.Display; import com.google.gwt.event.logical.shared.ResizeEvent; import com.google.gwt.event.logical.shared.ResizeHandler; import com.google.gwt.event.shared.HandlerRegistration; import com.google.gwt.http.client.UrlBuilder; import com.google.gwt.storage.client.Storage; import com.google.gwt.user.client.Window; import com.google.gwt.user.client.ui.RootPanel; /** * Use {@link ExtendedWebsocketControl} instead * * @author Oliver Schmid * */ @Deprecated public class WebsocketControl extends MultiCursorController implements ResizeHandler { private boolean opened = false; private JavaScriptObject websocket; private final List<MouseCursor> cursors = new ArrayList<MouseCursor>(); private final Map<String, MouseCursor> assignedMouseCursors = new HashMap<String, MouseCursor>(); private final Map<String, MouseCursor> preferredMouseCursors = new HashMap<String, MouseCursor>(); private final Set<MouseCursor> activeCursorsCounter = new HashSet<MouseCursor>(); private final Storage storage = Storage.getLocalStorageIfSupported(); private final int maxCursorsOnScreen = 5; private void initializeCursorList() { cursors.clear(); assignedMouseCursors.clear(); cursors.add(defineMouseCursor("black", "#1a1a1a")); cursors.add(defineMouseCursor("blue", "#336aa6")); cursors.add(defineMouseCursor("green", "#42a75b")); cursors.add(defineMouseCursor("grey", "#646663")); cursors.add(defineMouseCursor("red", "#d65555")); cursors.add(defineMouseCursor("yellow", "#f7d64c")); cursors.add(defineMouseCursor("purple", "#cb2c7a")); } private MouseCursor getCursorByColor(String color) { for (MouseCursor c : activeCursorsCounter) { if (c.getColor().equals(color)) return c; } return null; } private MouseCursor defineMouseCursor(String cursor, String color) { final MouseCursor c = new MouseCursor(cursor, color); c.addMouseCursorEventHandler(new Handler() { @Override public void onMouseCursorTimeout(MouseCursorTimeoutEvent event) { if (event.isDetached()) { GWT.log("Detaching cursor " + c.getFileName()); String uuid = null; for (String assignedCursor : assignedMouseCursors.keySet()) { if (assignedMouseCursors.get(assignedCursor) == c) { uuid = assignedCursor; break; } } if (uuid != null) { assignedMouseCursors.remove(uuid); if (storage != null) storage.removeItem("ch.unifr.pai.mice.multicursor.assignedCursor." + c.getFileName()); } if (!cursors.contains(c)) cursors.add(c); } activeCursorsCounter.remove(c); if (storage != null) storage.removeItem("ch.unifr.pai.mice.multicursor.activeCursor." + c.getFileName()); } }); if (storage != null) { String assigneduuid = storage.getItem("ch.unifr.pai.mice.multicursor.assignedCursor." + cursor); if (assigneduuid != null) assignedMouseCursors.put(assigneduuid, c); String preferreduuid = storage.getItem("ch.unifr.pai.mice.multicursor.preferredCursor." + cursor); if (preferreduuid != null) preferredMouseCursors.put(preferreduuid, c); String activeCursor = storage.getItem("ch.unifr.pai.mice.multicursor.activeCursor." + cursor); if (activeCursor != null) activeCursorsCounter.add(c); } if (!activeCursorsCounter.contains(c)) c.getElement().getStyle().setDisplay(Display.NONE); else c.show(); RootPanel.get().add(c); return c; } HandlerRegistration r; public native boolean isInIFrame() /*-{ return $wnd.top.location != $wnd.location; }-*/; @Override public void start() { if (!isInIFrame()) { initializeCursorList(); if (r != null) r.removeHandler(); r = Window.addResizeHandler(this); UrlBuilder b = Window.Location.createUrlBuilder(); b.setProtocol("ws"); b.setPath("mouseControlXBrowser"); b.setHash(null); String p = Window.Location.getPort(); Integer port; try { port = p != null ? Integer.parseInt(p) : 8080; } catch (NumberFormatException e) { port = 8080; } b.setPort(port + 1); for (String param : Window.Location.getParameterMap().keySet()) { b.removeParameter(param); } websocket = createWebsocket(this, b.buildString()); if (websocket != null) createOnBeforeUnloadHandler(websocket); } } @Override public void stop() { super.stop(); stopWebsocket(websocket); for (MouseCursor c : activeCursorsCounter) { c.hide(); } } private native void send(JavaScriptObject websocket, String message)/*-{ if (websocket != null) websocket.send(message); }-*/; private native JavaScriptObject createOnBeforeUnloadHandler(JavaScriptObject websocket)/*-{ $wnd.onbeforeunload = function() { //$wnd.alert("CLOSE WEBSOCKET: "+websocket); websocket.close(); } }-*/; private native JavaScriptObject stopWebsocket(JavaScriptObject websocket)/*-{ websocket.close(); }-*/; private native JavaScriptObject createWebsocket(WebsocketControl w, String url)/*-{ if ("WebSocket" in $wnd) { // Let us open a web socket var ws = new WebSocket(url); ws.onmessage = function(evt) { w.@ch.unifr.pai.twice.multipointer.client.WebsocketControl::onMessage(Ljava/lang/String;)(evt.data); } ws.onopen = function() { w.@ch.unifr.pai.twice.multipointer.client.WebsocketControl::onOpen()(); } ws.onclose = function() { w.@ch.unifr.pai.twice.multipointer.client.WebsocketControl::onClose()(); } //Add onbeforeunload to handle closing correctly in chrome $wnd.onbeforeunload = function() { ws.onclose = function() { }; ws.close(); } return ws; } else { $wnd .alert("This browser does not support multipointer functionalities (needs websockets)!"); } return null; }-*/; private void onMessage(String data) { if (data != null) { String[] values = data.split("@"); if (values.length > 0) { String uuid = values[0]; MouseCursor m = getOrCreateCursor(uuid); if (m != null) { boolean isActive = activeCursorsCounter.contains(m); if (activeCursorsCounter.size() < maxCursorsOnScreen || isActive) { if (!isActive) { activeCursorsCounter.add(m); if (storage != null) { storage.setItem("ch.unifr.pai.mice.multicursor.activeCursor." + m.getFileName(), "true"); } } if (values.length > 1) { String action = null; Map<String, String> params = new HashMap<String, String>(); for (int i = 1; i < values.length; i++) { String[] param = values[i].split("="); if (param[0].equals("a")) action = param[1]; else params.put(param[0], param[1]); } m.interpretMessage(action, params); } } } } } } private MouseCursor getOrCreateCursor(String uuid) { MouseCursor m = assignedMouseCursors.get(uuid); // If a cursor is already assigned to the uuid, return this one if (m != null) return m; if (cursors.size() > 0) { // otherwise Get the preferred mouse cursor for this uuid and check // if it's still available m = preferredMouseCursors.get(uuid); // If there is no preferred cursor or if the preferred cursor is // already in use, take another one if (m == null || !cursors.contains(m)) { m = cursors.get(0); preferredMouseCursors.put(uuid, m); if (storage != null) storage.setItem("ch.unifr.pai.mice.multicursor.preferredCursor." + m.getFileName(), uuid); } m.setUuid(uuid); cursors.remove(m); assignedMouseCursors.put(uuid, m); if (storage != null) storage.setItem("ch.unifr.pai.mice.multicursor.assignedCursor." + m.getFileName(), uuid); if (opened && websocket != null) { send(websocket, UUID.get() + "@c@" + uuid + "@" + m.getColor()); } return m; } return null; } private void onOpen() { this.opened = true; send(websocket, UUID.get() + "@s@" + Window.getClientWidth() + "@" + Window.getClientHeight()); // Window.alert("Multi cursor control started!"); } private void onClose() { if (!opened) { Window.alert("The websocket server is not reachable!"); } else { opened = false; // Window.alert("Stopping multi cursor control!"); } } @Override public void onResize(ResizeEvent event) { if (opened && websocket != null) { send(websocket, UUID.get() + "@r@" + Window.getClientWidth() + "@" + Window.getClientHeight()); } } @Override public void notifyCursor(String uuid, String action) { send(websocket, UUID.get() + "@" + action + "@" + uuid); } }