Java tutorial
package ch.unifr.pai.twice.mousecontrol.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.Date; import ch.unifr.pai.twice.authentication.client.Authentication; import ch.unifr.pai.twice.module.client.TWICEAnnotations.Configurable; import com.google.gwt.core.client.GWT; import com.google.gwt.core.client.Scheduler; import com.google.gwt.core.client.Scheduler.ScheduledCommand; import com.google.gwt.http.client.Request; import com.google.gwt.http.client.RequestBuilder; import com.google.gwt.http.client.RequestCallback; import com.google.gwt.http.client.RequestException; import com.google.gwt.http.client.Response; import com.google.gwt.regexp.shared.MatchResult; import com.google.gwt.regexp.shared.RegExp; import com.google.gwt.user.client.Command; import com.google.gwt.user.client.Event; import com.google.gwt.user.client.Event.NativePreviewEvent; import com.google.gwt.user.client.Event.NativePreviewHandler; import com.google.gwt.user.client.Timer; import com.google.gwt.user.client.Window; import com.google.gwt.user.client.ui.Label; import com.google.gwt.user.client.ui.LayoutPanel; import com.google.web.bindery.event.shared.HandlerRegistration; /** * A generic implementation of a remote mouse control component * * @author Oliver Schmid * */ public abstract class TouchPadWidget extends LayoutPanel { /** * The interval in ms of updating messages */ @Configurable("Movement interval") static int MOVEMENTUPDATEINTERVAL = 80; /** * The threshold of distance in pixels that has to be exceeded by a mouse movement to trigger an event */ @Configurable("Movement threshold") static int MOVEMENTTHRESHOLD = 0; /** * The factor with which the movement shall be increased */ @Configurable("Movement factor") static double MOVEFACTOR = 1.8; /** * The threshold of how long the mouse shall be pressed until the device switches to drag mode */ @Configurable("Mouse down threshold") static int MOUSEDOWNTHRESHOLD = 300; /** * In which interval the client shall try to assign a cursor on the shared screen */ @Configurable("Look for cursor interval") static int LOOKFORCURSORINTERVAL = 2000; private String uuid; private String host; private Integer port; private String currentColor; private String screenDimension; protected int screenWidth; protected int screenHeight; private boolean active = true; private int currentX = -1; private int currentY = -1; private boolean running; private boolean downLastAction = false; private boolean doLog = false; private StringBuilder log = new StringBuilder(); private String header; private String[] availableClients; private final Label label = new Label(); // private TextBox focusTextBox = new TextBox(); protected boolean dragging = false; // private final static String controlServlet = "mouseManager"; private final static String controlServlet = "mouseManagerXBrowser"; // private final static String controlServlet = "mouseManagerXBrowserWS"; public String getHeader() { return header; } public void setHeader(String header) { this.header = header; } /** * Add data to the log * * @param name * @param attributes * @param content */ public void addToLog(String name, String attributes, String content) { log.append("<").append(name); log.append(" time=\"").append(new Date().getTime()).append("\" uuid=\"").append(uuid) .append("\" color=\"" + getColor() + "\""); if (attributes != null) { log.append(" ").append(attributes); } log.append(">"); if (content != null) log.append(content); log.append("</").append(name).append(">"); } /** * Clear the log * * @return the log state before clearance */ public String flushLog() { String result = log.toString(); log = new StringBuilder(); return result; } /** * @return true if the component is writing to the log */ public boolean isDoLog() { return doLog; } /** * define if the component shall write to the log * * @param doLog */ public void setDoLog(boolean doLog) { this.doLog = doLog; } /** * defines if drag is enabled */ protected boolean dragModeEnabled = true; public TouchPadWidget(boolean handleFocus) { super(); // add(focusTextBox); add(label); // focusTextBox.getElement().getStyle().setZIndex(-1); // focusTextBox.getElement().getStyle().setVisibility(Visibility.HIDDEN); // send(null); } /** * @return true if drag mode is enabled, false otherwise */ public boolean isDragModeEnabled() { return dragModeEnabled; } /** * set if drag mode is enabled * * @param dragModeEnabled */ public void setDragModeEnabled(boolean dragModeEnabled) { this.dragModeEnabled = dragModeEnabled; } /** * timer which sends out movement events */ private final Timer movement = new Timer() { @Override public void run() { int x = getX(); int y = getY(); if (currentX != x || currentY != y) { move(x, y); currentX = x; currentY = y; } } }; /** * @return the id of the current available shared screen */ private String getCurrentClient() { // TODO the user should select the client if there are multiple. For // testing, we take the latest return availableClients != null && availableClients.length > 0 ? availableClients[availableClients.length - 1] : null; } /** * if no cursor is available on the shared screen, try to gather one with the given interval */ private void noCursorAvailable() { setActive(false); if (lookForCursor != null) lookForCursor.schedule(LOOKFORCURSORINTERVAL); } /** * If a cursor is assigned, start to fire events */ private void cursorAssigned() { setActive(true); running = true; String updateInterval = Window.Location.getParameter("update"); if (updateInterval != null) MOVEMENTUPDATEINTERVAL = Integer.parseInt(updateInterval); movement.scheduleRepeating(MOVEMENTUPDATEINTERVAL); keyboardHandler = Event.addNativePreviewHandler(keyboardPreviewHandler); } /** * Handler for keyboard events and invocation of the key events on the shared screen */ protected NativePreviewHandler keyboardPreviewHandler = new NativePreviewHandler() { @Override public void onPreviewNativeEvent(NativePreviewEvent event) { switch (event.getTypeInt()) { case Event.ONKEYDOWN: // if (handleFocus) // focusTextBox.setFocus(true); send("a=kd&kc=" + event.getNativeEvent().getKeyCode() + "&cc=" + event.getNativeEvent().getCharCode()); break; case Event.ONKEYUP: // if (handleFocus) // focusTextBox.setFocus(true); send("a=ku&kc=" + event.getNativeEvent().getKeyCode() + "&cc=" + event.getNativeEvent().getCharCode()); break; case Event.ONKEYPRESS: // if (handleFocus) // focusTextBox.setFocus(true); send("a=kp&kc=" + event.getNativeEvent().getKeyCode() + "&cc=" + event.getNativeEvent().getCharCode()); break; } } }; protected HandlerRegistration keyboardHandler; private Timer lookForCursor; /** * Invoked if the last action has changed. Forces the stop or the start of dragging mode based on information originated on the server * * @param action */ protected void onActionChanged(String action) { if (action != null) { if (action.equals("startDrag")) dragging = true; else if (action.equals("endDrag")) stopDragging(); } } /** * stops the dragging */ protected void stopDragging() { dragging = false; } /** * starts the execution of the component */ public void start() { if (!running) { label.setText("looking for available remote-clients"); getAvailableClients(new Command() { @Override public void execute() { label.setText((availableClients == null ? "0" : availableClients.length) + " clients found"); if (getCurrentClient() != null) { label.setText("looking for cursor on client " + getCurrentClient()); lookForCursor = new Timer() { @Override public void run() { try { new RequestBuilder(RequestBuilder.GET, GWT.getHostPageBaseURL() + controlServlet + "?a=x" + (getCurrentClient() != null ? "&targetUUID=" + getCurrentClient() : "") + (uuid != null ? "&uuid=" + uuid : "") + (host != null ? "&host=" + host : "") + (port != null ? "&port=" + port : "")).sendRequest(null, new RequestCallback() { @Override public void onResponseReceived(Request request, Response response) { if (response.getStatusCode() > 400) onError(request, null); label.setText("GOT DATA: " + response.getText()); String color = extractColor(response); if (color == null || color.isEmpty() || color.equals("#null")) color = null; extractLastAction(response); setScreenDimension(extractScreenDimensions(response)); if (color != null) { setColor(color); cursorAssigned(); } else { noCursorAvailable(); } } @Override public void onError(Request request, Throwable exception) { noCursorAvailable(); } }); } catch (RequestException e) { noCursorAvailable(); } } }; lookForCursor.run(); } } }); } } /** * stops the execution of the component (also interrupts the sending of events). */ public void stop() { if (running) { running = false; movement.cancel(); } } /** * Define the cursor id as well as the host and port for the target of the mouse control events. If not defined, the session id, localhost and the standard * port will be used. * * @param uuid * @param host * @param port */ public void initialize(String uuid, String host, Integer port) { this.uuid = uuid; this.host = host; this.port = port; } /** * send a mouse down event to the mouse control servlet * * @param leftButton */ protected void down(boolean leftButton) { send("a=d&b=" + (leftButton ? "l" : "r")); downLastAction = true; } /** * send a mouse up event to the mouse control servlet * * @param leftButton */ protected void up(boolean leftButton) { send("a=u&b=" + (leftButton ? "l" : "r")); downLastAction = false; } /** * send a hide request to the mouse control servlet that lets the mouse pointer disappear on the shared screen */ protected void hide() { Scheduler.get().scheduleDeferred(new ScheduledCommand() { @Override public void execute() { send("a=h"); } }); } /** * @return the current x coordinate of the mouse pointer on the shared screen */ protected abstract int getX(); /** * @return the current y coordinate of the mouse pointer on the shared screen */ protected abstract int getY(); /** * Send a movement request to the mouse control servlet * * @param x * @param y */ protected void move(int x, int y) { if (screenDimension == null) send(null); else send("a=m&x=" + x + "&y=" + y); } /** * Delegator method to send a query to the mouse control servlet without callback * * @param query */ protected void send(String query) { send(query, null); } /** * Sends a request to the server to get the current status * * @param callback */ protected void getStatus(Command callback) { send(null, callback); } private boolean noConnection; /** * Sends the given query to the mouse pointer controller servlet * * @param query * @param callback */ protected void send(String query, final Command callback) { try { if (active) { new RequestBuilder(RequestBuilder.GET, GWT.getHostPageBaseURL() + controlServlet + "?" + (query != null ? query : "a=x") + (getCurrentClient() != null ? "&targetUUID=" + getCurrentClient() : "") + (uuid != null ? "&uuid=" + uuid : "") + (host != null ? "&host=" + host : "") + (port != null ? "&port=" + port : "") + ("&user=" + Authentication.getUserName())) .sendRequest(null, new RequestCallback() { @Override public void onResponseReceived(Request request, Response response) { if (response.getStatusCode() > 400) onError(request, null); String color = extractColor(response); if (response.getText().trim().isEmpty()) { label.setText("No connection available"); noConnection = true; } else { if (noConnection) { label.setText(""); noConnection = false; } if (color == null || color.isEmpty() || color.equals("#null")) color = null; extractLastAction(response); setColor(color); setScreenDimension(extractScreenDimensions(response)); if (callback != null) callback.execute(); } } @Override public void onError(Request request, Throwable exception) { setActive(false); } }); } } catch (Exception e) { e.printStackTrace(); } } /** * sets the mouse control active or inactive * * @param active */ private void setActive(boolean active) { this.active = active; if (!active) { this.getElement().getStyle().setBackgroundColor("grey"); label.setText("Looking for available cursors... not found one so long."); } else { label.setText(""); } } /** * Further actions when the dimensions of the shared screen change */ protected abstract void updateScreenDimensions(); /** * Adapts the widget to the given screen dimensions of the shared screen * * @param dimension */ private void setScreenDimension(String dimension) { if (dimension != null && (screenDimension == null || !screenDimension.equals(dimension))) { String[] values = dimension.split("x"); if (values.length == 2) { screenWidth = Integer.parseInt(values[0]); screenHeight = Integer.parseInt(values[1]); updateScreenDimensions(); screenDimension = dimension; } } } /** * @param resp * @return the screen dimensions of the shared screen separated by a "x" */ private static String extractScreenDimensions(Response resp) { return extractByRegex(resp, "[0-9]*x[0-9]*"); } /** * @param resp * @return the color of the assigned the mouse pointer */ private static String extractColor(Response resp) { return extractByRegex(resp, "#.{6}"); } protected String lastAction = null; /** * @param response * - the last action that has been applied */ private void extractLastAction(Response response) { String[] split = response.getText().split("@"); if (split.length > 2) { if (!split[2].equals(lastAction)) { lastAction = split[2]; onActionChanged(lastAction); GWT.log("Action changed: " + lastAction); } } } /** * Helper method to extract values from the HTTP-response by the given regular expression * * @param response * @param regex * @return */ private static String extractByRegex(Response response, String regex) { RegExp re = RegExp.compile(regex); MatchResult result = re.exec(response.getText()); return result.getGroup(0); } /** * Sets the color of the font based on the brightness of the background color either to black or to white * * @param color */ protected void setColor(String color) { if (color != null) { color = color.trim(); if (currentColor == null || !currentColor.equals(color)) { currentColor = color; this.getElement().getStyle().setBackgroundColor(color); // this.getElement().getStyle().setColor(getInvertedColor(color)); this.getElement().getStyle().setColor(isColorBright(color) ? "#000000" : "#ffffff"); } } } /** * @param color * @return true if the color brightness is above the average and false if not */ protected boolean isColorBright(String color) { if (color != null) { if (color.startsWith("#") && color.length() == 7) { try { Integer red = Integer.parseInt(color.substring(1, 3).toLowerCase(), 16); Integer green = Integer.parseInt(color.substring(3, 5).toLowerCase(), 16); Integer blue = Integer.parseInt(color.substring(5, 7).toLowerCase(), 16); Double d = (red + green + blue) / 3.0; // 128 is the average brightness (16/2) return d > 128; } catch (NumberFormatException e) { return true; } } } return true; } /** * Request the server for available shared devices * * @param callback */ private void getAvailableClients(final Command callback) { try { new RequestBuilder(RequestBuilder.GET, GWT.getHostPageBaseURL() + controlServlet + "?a=g") .sendRequest(null, new RequestCallback() { @Override public void onResponseReceived(Request request, Response response) { if (response.getText() != null && !response.getText().isEmpty()) { availableClients = response.getText().split("\n"); } if (callback != null) callback.execute(); } @Override public void onError(Request request, Throwable exception) { GWT.log("Available clients request", exception); if (callback != null) callback.execute(); } }); } catch (RequestException e) { GWT.log("Request Exception", e); if (callback != null) callback.execute(); } } /** * @return the color of the mouse pointer / background */ public String getColor() { return currentColor; } /** * @param color * in HTML hexadecimal writing (e.g. "#000000"); * @return the inverted color */ protected String getInvertedColor(String color) { if (color != null) { if (color.startsWith("#")) { String hexString = color.substring(1); Integer i; Integer maxHex; try { i = Integer.parseInt(hexString.toLowerCase(), 16); maxHex = Integer.parseInt("ffffff", 16); } catch (NumberFormatException e) { return "#000000"; } String newHexString = Integer.toHexString(maxHex - i); return "#" + newHexString; } } return "#000000"; } /** * @return true if the widget shall be attached to the root panel or false if it takes care about the attachment by itself */ public boolean attachToRootPanel() { return false; } }