+/*
+ * 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.helpers;
+
+
+import java.io.Writer;
+import java.net.DatagramSocket;
+import java.net.InetAddress;
+import java.net.DatagramPacket;
+import java.net.UnknownHostException;
+import java.net.SocketException;
+import java.io.IOException;
+import java.net.URL;
+import java.net.MalformedURLException;
+
+/**
+ SyslogWriter is a wrapper around the java.net.DatagramSocket class
+ so that it behaves like a java.io.Writer.
+
+ @since 0.7.3
+*/
+public class SyslogWriter extends Writer {
+
+ final int SYSLOG_PORT = 514;
+ /**
+ * Host string from last constructed SyslogWriter.
+ * @deprecated
+ */
+ static String syslogHost;
+
+ private InetAddress address;
+ private final int port;
+ private DatagramSocket ds;
+
+ /**
+ * Constructs a new instance of SyslogWriter.
+ * @param syslogHost host name, may not be null. A port
+ * may be specified by following the name or IPv4 literal address with
+ * a colon and a decimal port number. To specify a port with an IPv6
+ * address, enclose the IPv6 address in square brackets before appending
+ * the colon and decimal port number.
+ */
+ public
+ SyslogWriter(final String syslogHost) {
+ SyslogWriter.syslogHost = syslogHost;
+ if (syslogHost == null) {
+ throw new NullPointerException("syslogHost");
+ }
+
+ String host = syslogHost;
+ int urlPort = -1;
+
+ //
+ // If not an unbracketed IPv6 address then
+ // parse as a URL
+ //
+ if (host.indexOf("[") != -1 || host.indexOf(':') == host.lastIndexOf(':')) {
+ try {
+ URL url = new URL("http://" + host);
+ if (url.getHost() != null) {
+ host = url.getHost();
+ // if host is a IPv6 literal, strip off the brackets
+ if(host.startsWith("[") && host.charAt(host.length() - 1) == ']') {
+ host = host.substring(1, host.length() - 1);
+ }
+ urlPort = url.getPort();
+ }
+ } catch(MalformedURLException e) {
+ LogLog.error("Malformed URL: will attempt to interpret as InetAddress.", e);
+ }
+ }
+
+ if (urlPort == -1) {
+ urlPort = SYSLOG_PORT;
+ }
+ port = urlPort;
+
+ try {
+ this.address = InetAddress.getByName(host);
+ }
+ catch (UnknownHostException e) {
+ LogLog.error("Could not find " + host +
+ ". All logging will FAIL.", e);
+ }
+
+ try {
+ this.ds = new DatagramSocket();
+ }
+ catch (SocketException e) {
+ e.printStackTrace();
+ LogLog.error("Could not instantiate DatagramSocket to " + host +
+ ". All logging will FAIL.", e);
+ }
+
+ }
+
+
+ public
+ void write(char[] buf, int off, int len) throws IOException {
+ this.write(new String(buf, off, len));
+ }
+
+ public
+ void write(final String string) throws IOException {
+
+ if(this.ds != null && this.address != null) {
+ byte[] bytes = string.getBytes();
+ //
+ // syslog packets must be less than 1024 bytes
+ //
+ int bytesLength = bytes.length;
+ if (bytesLength >= 1024) {
+ bytesLength = 1024;
+ }
+ DatagramPacket packet = new DatagramPacket(bytes, bytesLength,
+ address, port);
+ ds.send(packet);
+ }
+
+ }
+
+ public
+ void flush() {}
+
+ public void close() {
+ if (ds != null) {
+ ds.close();
+ }
+ }
+}