001 /** 002 The contents of this file are subject to the Mozilla Public License Version 1.1 003 (the "License"); you may not use this file except in compliance with the License. 004 You may obtain a copy of the License at http://www.mozilla.org/MPL/ 005 Software distributed under the License is distributed on an "AS IS" basis, 006 WITHOUT WARRANTY OF ANY KIND, either express or implied. See the License for the 007 specific language governing rights and limitations under the License. 008 009 The Original Code is "Log.java". Description: 010 "Manages the logging of exceptions and status information" 011 012 The Initial Developer of the Original Code is University Health Network. Copyright (C) 013 2001. All Rights Reserved. 014 015 Contributor(s): ______________________________________. 016 017 Alternatively, the contents of this file may be used under the terms of the 018 GNU General Public License (the ?GPL?), in which case the provisions of the GPL are 019 applicable instead of those above. If you wish to allow use of your version of this 020 file only under the terms of the GPL and not to allow others to use your version 021 of this file under the MPL, indicate your decision by deleting the provisions above 022 and replace them with the notice and other provisions required by the GPL License. 023 If you do not delete the provisions above, a recipient may use your version of 024 this file under either the MPL or the GPL. 025 026 */ 027 028 package ca.uhn.hl7v2; 029 030 /** 031 * <p>Manages the logging of exceptions and status information.<p> 032 * <p>To select a particular implementation with which to log, set the system property 033 * <code>ca.on.uhn.hl7.log</code> to the fully qualified class name of a subclass 034 * of Log before getInstance() is first called. If this property is not set, the 035 * default FileLog is used with the log files "hl7_exceptions_<name>_<date>.log" and "hl7_status_<name>_<date>.log" in 036 * the working directory.</p> 037 * <p>The logs entries arising from a particular VM can be named, to distinguish them from 038 * log entries from other VMs. To do this, set the system property "ca.uhn.hl7v2.log.name" to something 039 * descriptive.<p> 040 * @author Bryan Tripp (bryan_tripp@sourceforge.net) 041 * 042 * @deprecated MUST USE jakarta-commons-logging 043 */ 044 public abstract class Log { 045 046 private static Log log; 047 048 /** 049 * <p>Returns the singleton instance of Log. The Log returned will be an instance of a 050 * subclass that uses a specific means of logging (e.g. logging to a particular text 051 * file or database). </p> 052 * @exception LogException there is a problem opening the Log or the subclass 053 * specified can not be found or is not in fact a subclass of Log. 054 */ 055 public static synchronized Log getInstance() throws LogException { 056 if (log == null) { 057 String logClass = System.getProperty("ca.on.uhn.hl7.log"); 058 if (logClass == null) { 059 log = new FileLog(); 060 } else { 061 try { 062 log = (Log)Class.forName(logClass).newInstance(); 063 } catch (ClassNotFoundException ce) { 064 throw new LogException("Can't initialize HL7 Log - can't find the Log subclass " + 065 logClass + "."); 066 } catch (ClassCastException cce) { 067 throw new LogException("Can't initialize HL7 Log - the specified log class - " + 068 logClass + " - does not extend ca.on.uhn.hl7.Log"); 069 } catch (Exception e) { 070 throw new LogException("Can't initialize HL7 log of class " + 071 logClass + ": " + e.getClass().getName() + ": " + e.getMessage()); 072 } 073 } 074 } 075 return log; 076 077 } 078 079 080 /** 081 * Convenience method for logging exceptions - if a LogException 082 * is thrown while logging, the original exception is written to std out 083 * and no exception is thrown by this method. 084 */ 085 public static void tryToLog(Exception e, String message) { 086 try { 087 Log.getInstance().log(e, message); 088 } catch (Exception loge) { 089 loge.printStackTrace(); 090 System.err.println("\r\n\r\n------------------\r\nCan't write to exception log - writing to standard out ..." + message); 091 e.printStackTrace(); 092 System.err.println("-----------------\r\n\r\n"); 093 094 } 095 } 096 097 /** 098 * Logs an Exception. 099 * @exception LogException if there is an error writing to the log. 100 */ 101 public abstract void log(Exception e, String message) throws LogException; 102 103 /** 104 * Logs a status message. 105 * @exception LogException if there is an error writing to the log. 106 */ 107 public abstract void log(String status) throws LogException; 108 109 /** 110 * Returns a description of where logged data are being stored. Implementing 111 * classes should return sufficient text to allow a human who reads this message 112 * to independently view information in the log (e.g. the file name, password for the 113 * database, etc.). 114 */ 115 public abstract String getDescription(); 116 117 //test 118 public static void main(String args[]) { 119 try { 120 throw new LogException("this is a test message"); 121 } catch (Exception e) { 122 try { 123 Log.getInstance().log(e, "thing message"); 124 } catch (LogException le) { 125 e.printStackTrace(); 126 } 127 } 128 try { 129 throw new LogException("this is a test message"); 130 } catch (Exception e) { 131 try { 132 Log.getInstance().log(e, ""); 133 } catch (LogException le) { 134 e.printStackTrace(); 135 } 136 } 137 try { 138 throw new LogException("this is a test message"); 139 } catch (Exception e) { 140 try { 141 Log.getInstance().log(e, ""); 142 } catch (LogException le) { 143 e.printStackTrace(); 144 } 145 } 146 try { 147 Log.getInstance().log("status 1"); 148 } catch (Exception e) { 149 e.printStackTrace(); 150 } 151 try { 152 Log.getInstance().log("status 2"); 153 } catch (Exception e) { 154 e.printStackTrace(); 155 } 156 } 157 }