headless backend demo
authorKevin Lamonte <kevin.lamonte@gmail.com>
Fri, 8 Nov 2019 18:36:31 +0000 (12:36 -0600)
committerKevin Lamonte <kevin.lamonte@gmail.com>
Fri, 8 Nov 2019 18:36:31 +0000 (12:36 -0600)
src/jexer/backend/ECMA48Terminal.java
src/jexer/backend/HeadlessBackend.java [new file with mode: 0644]
src/jexer/demos/Demo8.java [new file with mode: 0644]
src/jexer/demos/Demo8.properties [new file with mode: 0644]

index ed2715c834bc3402062690cd270b4846c4dae618..0389f3d388e3146c64aeab299c5f2ec357110a70 100644 (file)
@@ -1643,7 +1643,10 @@ public class ECMA48Terminal extends LogicalScreen
      * @return the width in pixels of a character cell
      */
     public int getTextWidth() {
-        return (widthPixels / sessionInfo.getWindowWidth());
+        if (sessionInfo.getWindowWidth() > 0) {
+            return (widthPixels / sessionInfo.getWindowWidth());
+        }
+        return 16;
     }
 
     /**
@@ -1652,7 +1655,10 @@ public class ECMA48Terminal extends LogicalScreen
      * @return the height in pixels of a character cell
      */
     public int getTextHeight() {
-        return (heightPixels / sessionInfo.getWindowHeight());
+        if (sessionInfo.getWindowHeight() > 0) {
+            return (heightPixels / sessionInfo.getWindowHeight());
+        }
+        return 20;
     }
 
     /**
diff --git a/src/jexer/backend/HeadlessBackend.java b/src/jexer/backend/HeadlessBackend.java
new file mode 100644 (file)
index 0000000..19fb589
--- /dev/null
@@ -0,0 +1,134 @@
+/*
+ * Jexer - Java Text User Interface
+ *
+ * The MIT License (MIT)
+ *
+ * Copyright (C) 2019 Kevin Lamonte
+ *
+ * Permission is hereby granted, free of charge, to any person obtaining a
+ * copy of this software and associated documentation files (the "Software"),
+ * to deal in the Software without restriction, including without limitation
+ * the rights to use, copy, modify, merge, publish, distribute, sublicense,
+ * and/or sell copies of the Software, and to permit persons to whom the
+ * Software is furnished to do so, subject to the following conditions:
+ *
+ * The above copyright notice and this permission notice shall be included in
+ * all copies or substantial portions of the Software.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+ * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+ * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL
+ * THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+ * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
+ * FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER
+ * DEALINGS IN THE SOFTWARE.
+ *
+ * @author Kevin Lamonte [kevin.lamonte@gmail.com]
+ * @version 1
+ */
+package jexer.backend;
+
+import java.util.List;
+
+import jexer.event.TInputEvent;
+
+/**
+ * HeadlessBackend
+ */
+public class HeadlessBackend extends LogicalScreen implements Backend {
+
+    // ------------------------------------------------------------------------
+    // Variables --------------------------------------------------------------
+    // ------------------------------------------------------------------------
+
+    /**
+     * The session information.
+     */
+    private SessionInfo sessionInfo;
+
+    // ------------------------------------------------------------------------
+    // Constructors -----------------------------------------------------------
+    // ------------------------------------------------------------------------
+
+    /**
+     * Public constructor.
+     */
+    public HeadlessBackend() {
+        sessionInfo = new TSessionInfo(width, height);
+    }
+
+    // ------------------------------------------------------------------------
+    // Backend ----------------------------------------------------------------
+    // ------------------------------------------------------------------------
+
+    /**
+     * Getter for sessionInfo.
+     *
+     * @return the SessionInfo
+     */
+    public final SessionInfo getSessionInfo() {
+        return sessionInfo;
+    }
+
+    /**
+     * Get a Screen, which displays the text cells to the user.
+     *
+     * @return the Screen
+     */
+    public Screen getScreen() {
+        return this;
+    }
+
+    /**
+     * Subclasses must provide an implementation that syncs the logical
+     * screen to the physical device.
+     */
+    public void flushScreen() {
+        // NOP
+    }
+
+    /**
+     * Check if there are events in the queue.
+     *
+     * @return if true, getEvents() has something to return to the application
+     */
+    public boolean hasEvents() {
+        return false;
+    }
+
+    /**
+     * Subclasses must provide an implementation to get keyboard, mouse, and
+     * screen resize events.
+     *
+     * @param queue list to append new events to
+     */
+    public void getEvents(List<TInputEvent> queue) {
+        // NOP
+    }
+
+    /**
+     * Subclasses must provide an implementation that closes sockets,
+     * restores console, etc.
+     */
+    public void shutdown() {
+        // NOP
+    }
+
+    /**
+     * Set listener to a different Object.
+     *
+     * @param listener the new listening object that run() wakes up on new
+     * input
+     */
+    public void setListener(final Object listener) {
+        // NOP
+    }
+
+    /**
+     * Reload backend options from System properties.
+     */
+    public void reloadOptions() {
+        // NOP
+    }
+
+}
diff --git a/src/jexer/demos/Demo8.java b/src/jexer/demos/Demo8.java
new file mode 100644 (file)
index 0000000..19fe5ff
--- /dev/null
@@ -0,0 +1,154 @@
+/*
+ * Jexer - Java Text User Interface
+ *
+ * The MIT License (MIT)
+ *
+ * Copyright (C) 2019 Kevin Lamonte
+ *
+ * Permission is hereby granted, free of charge, to any person obtaining a
+ * copy of this software and associated documentation files (the "Software"),
+ * to deal in the Software without restriction, including without limitation
+ * the rights to use, copy, modify, merge, publish, distribute, sublicense,
+ * and/or sell copies of the Software, and to permit persons to whom the
+ * Software is furnished to do so, subject to the following conditions:
+ *
+ * The above copyright notice and this permission notice shall be included in
+ * all copies or substantial portions of the Software.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+ * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+ * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL
+ * THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+ * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
+ * FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER
+ * DEALINGS IN THE SOFTWARE.
+ *
+ * @author Kevin Lamonte [kevin.lamonte@gmail.com]
+ * @version 1
+ */
+package jexer.demos;
+
+import java.net.ServerSocket;
+import java.net.Socket;
+import java.text.MessageFormat;
+import java.util.ResourceBundle;
+
+import jexer.TApplication;
+import jexer.backend.*;
+import jexer.demos.DemoApplication;
+import jexer.net.TelnetServerSocket;
+
+
+/**
+ * This class shows off the use of MultiBackend and MultiScreen.
+ */
+public class Demo8 {
+
+    /**
+     * Translated strings.
+     */
+    private static final ResourceBundle i18n = ResourceBundle.getBundle(Demo8.class.getName());
+
+    // ------------------------------------------------------------------------
+    // Demo8 ------------------------------------------------------------------
+    // ------------------------------------------------------------------------
+
+    /**
+     * Main entry point.
+     *
+     * @param args Command line arguments
+     */
+    public static void main(final String [] args) {
+        ServerSocket server = null;
+        try {
+
+            /*
+             * In this demo we will create a headless application that anyone
+             * can telnet to.
+             */
+
+            /*
+             * Check the arguments for the port to listen on.
+             */
+            if (args.length == 0) {
+                System.err.println(i18n.getString("usageString"));
+                return;
+            }
+            int port = Integer.parseInt(args[0]);
+
+            /*
+             * We create a headless screen and use it to establish a
+             * MultiBackend.
+             */
+            HeadlessBackend headlessBackend = new HeadlessBackend();
+            MultiBackend multiBackend = new MultiBackend(headlessBackend);
+
+            /*
+             * Now we create the shared application (a standard demo) and
+             * spin it up.
+             */
+            DemoApplication demoApp = new DemoApplication(multiBackend);
+            (new Thread(demoApp)).start();
+            multiBackend.setListener(demoApp);
+
+            /*
+             * Fire up the telnet server.
+             */
+            server = new TelnetServerSocket(port);
+            while (demoApp.isRunning()) {
+                Socket socket = server.accept();
+                System.out.println(MessageFormat.
+                    format(i18n.getString("newConnection"), socket));
+
+                ECMA48Backend ecmaBackend = new ECMA48Backend(demoApp,
+                    socket.getInputStream(),
+                    socket.getOutputStream());
+
+                /*
+                 * Add this screen to the MultiBackend, and at this point we
+                 * have the telnet client able to use the shared demo
+                 * application.
+                 */
+                multiBackend.addBackend(ecmaBackend);
+
+                /*
+                 * Emit the connection information from telnet.
+                 */
+                Thread.sleep(500);
+                System.out.println(MessageFormat.
+                    format(i18n.getString("terminal"),
+                    ((jexer.net.TelnetInputStream) socket.getInputStream()).
+                        getTerminalType()));
+                System.out.println(MessageFormat.
+                    format(i18n.getString("username"),
+                    ((jexer.net.TelnetInputStream) socket.getInputStream()).
+                        getUsername()));
+                System.out.println(MessageFormat.
+                    format(i18n.getString("language"),
+                    ((jexer.net.TelnetInputStream) socket.getInputStream()).
+                        getLanguage()));
+
+            } // while (demoApp.isRunning())
+
+            /*
+             * When the application exits, kill all of the connections too.
+             */
+            multiBackend.shutdown();
+            server.close();
+
+            System.out.println(i18n.getString("exitMain"));
+
+        } catch (Exception e) {
+            e.printStackTrace();
+        } finally {
+            if (server != null) {
+                try {
+                    server.close();
+                } catch (Exception e) {
+                    // SQUASH
+                }
+            }
+        }
+    }
+
+}
diff --git a/src/jexer/demos/Demo8.properties b/src/jexer/demos/Demo8.properties
new file mode 100644 (file)
index 0000000..08a8217
--- /dev/null
@@ -0,0 +1,6 @@
+usageString=USAGE: java -cp jexer.jar jexer.demos.Demo8 port
+newConnection=New connection: {0}
+username=\ \ \ username: {0}
+language=\ \ \ language: {0}
+terminal=\ \ \ terminal: {0}
+exitMain=Main thread is exiting...