--- /dev/null
+/*
+ * Licensed to the Apache Software Foundation (ASF) under one or more
+ * contributor license agreements. See the NOTICE file distributed with
+ * this work for additional information regarding copyright ownership.
+ * The ASF licenses this file to You 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.
+ */
+
+package org.apache.log4j.net;
+
+import org.apache.log4j.AppenderSkeleton;
+import org.apache.log4j.helpers.LogLog;
+import org.apache.log4j.spi.LoggingEvent;
+
+import java.io.IOException;
+import java.io.PrintWriter;
+import java.io.InterruptedIOException;
+import java.net.ServerSocket;
+import java.net.Socket;
+import java.util.Enumeration;
+import java.util.Iterator;
+import java.util.Vector;
+
+/**
+ <p>The TelnetAppender is a log4j appender that specializes in
+ writing to a read-only socket. The output is provided in a
+ telnet-friendly way so that a log can be monitored over TCP/IP.
+ Clients using telnet connect to the socket and receive log data.
+ This is handy for remote monitoring, especially when monitoring a
+ servlet.
+
+ <p>Here is a list of the available configuration options:
+
+ <table border=1>
+ <tr>
+ <th>Name</th>
+ <th>Requirement</th>
+ <th>Description</th>
+ <th>Sample Value</th>
+ </tr>
+
+ <tr>
+ <td>Port</td>
+ <td>optional</td>
+ <td>This parameter determines the port to use for announcing log events. The default port is 23 (telnet).</td>
+ <td>5875</td>
+ </table>
+
+ @author <a HREF="mailto:jay@v-wave.com">Jay Funnell</a>
+*/
+
+public class TelnetAppender extends AppenderSkeleton {
+
+ private static final String EOL = "\r\n";
+ private SocketHandler sh;
+ private int port = 23;
+
+ /**
+ This appender requires a layout to format the text to the
+ attached client(s). */
+ public boolean requiresLayout() {
+ return true;
+ }
+
+ /** all of the options have been set, create the socket handler and
+ wait for connections. */
+ public void activateOptions() {
+ try {
+ sh = new SocketHandler(port);
+ sh.start();
+ }
+ catch(InterruptedIOException e) {
+ Thread.currentThread().interrupt();
+ e.printStackTrace();
+ } catch(IOException e) {
+ e.printStackTrace();
+ } catch(RuntimeException e) {
+ e.printStackTrace();
+ }
+ super.activateOptions();
+ }
+
+ public
+ int getPort() {
+ return port;
+ }
+
+ public
+ void setPort(int port) {
+ this.port = port;
+ }
+
+
+ /** shuts down the appender. */
+ public void close() {
+ if (sh != null) {
+ sh.close();
+ try {
+ sh.join();
+ } catch(InterruptedException ex) {
+ Thread.currentThread().interrupt();
+ }
+ }
+ }
+
+ /** Handles a log event. For this appender, that means writing the
+ message to each connected client. */
+ protected void append(LoggingEvent event) {
+ if(sh != null) {
+ sh.send(layout.format(event));
+ if(layout.ignoresThrowable()) {
+ String[] s = event.getThrowableStrRep();
+ if (s != null) {
+ StringBuffer buf = new StringBuffer();
+ for(int i = 0; i < s.length; i++) {
+ buf.append(s[i]);
+ buf.append(EOL);
+ }
+ sh.send(buf.toString());
+ }
+ }
+ }
+ }
+
+ //---------------------------------------------------------- SocketHandler:
+
+ /** The SocketHandler class is used to accept connections from
+ clients. It is threaded so that clients can connect/disconnect
+ asynchronously. */
+ protected class SocketHandler extends Thread {
+
+ private Vector writers = new Vector();
+ private Vector connections = new Vector();
+ private ServerSocket serverSocket;
+ private int MAX_CONNECTIONS = 20;
+
+ public void finalize() {
+ close();
+ }
+
+ /**
+ * make sure we close all network connections when this handler is destroyed.
+ * @since 1.2.15
+ */
+ public void close() {
+ synchronized(this) {
+ for(Enumeration e = connections.elements();e.hasMoreElements();) {
+ try {
+ ((Socket)e.nextElement()).close();
+ } catch(InterruptedIOException ex) {
+ Thread.currentThread().interrupt();
+ } catch(IOException ex) {
+ } catch(RuntimeException ex) {
+ }
+ }
+ }
+
+ try {
+ serverSocket.close();
+ } catch(InterruptedIOException ex) {
+ Thread.currentThread().interrupt();
+ } catch(IOException ex) {
+ } catch(RuntimeException ex) {
+ }
+ }
+
+ /** sends a message to each of the clients in telnet-friendly output. */
+ public synchronized void send(final String message) {
+ Iterator ce = connections.iterator();
+ for(Iterator e = writers.iterator();e.hasNext();) {
+ ce.next();
+ PrintWriter writer = (PrintWriter)e.next();
+ writer.print(message);
+ if(writer.checkError()) {
+ ce.remove();
+ e.remove();
+ }
+ }
+ }
+
+ /**
+ Continually accepts client connections. Client connections
+ are refused when MAX_CONNECTIONS is reached.
+ */
+ public void run() {
+ while(!serverSocket.isClosed()) {
+ try {
+ Socket newClient = serverSocket.accept();
+ PrintWriter pw = new PrintWriter(newClient.getOutputStream());
+ if(connections.size() < MAX_CONNECTIONS) {
+ synchronized(this) {
+ connections.addElement(newClient);
+ writers.addElement(pw);
+ pw.print("TelnetAppender v1.0 (" + connections.size()
+ + " active connections)" + EOL + EOL);
+ pw.flush();
+ }
+ } else {
+ pw.print("Too many connections." + EOL);
+ pw.flush();
+ newClient.close();
+ }
+ } catch(Exception e) {
+ if (e instanceof InterruptedIOException || e instanceof InterruptedException) {
+ Thread.currentThread().interrupt();
+ }
+ if (!serverSocket.isClosed()) {
+ LogLog.error("Encountered error while in SocketHandler loop.", e);
+ }
+ break;
+ }
+ }
+
+ try {
+ serverSocket.close();
+ } catch(InterruptedIOException ex) {
+ Thread.currentThread().interrupt();
+ } catch(IOException ex) {
+ }
+ }
+
+ public SocketHandler(int port) throws IOException {
+ serverSocket = new ServerSocket(port);
+ setName("TelnetAppender-" + getName() + "-" + port);
+ }
+
+ }
+}
git://source.jalview.org / jalview.git / blobdiff