legacy/org.argeo.slc.support/src/org/argeo/slc/log4j/SlcExecutionAppender.java

   1 package org.argeo.slc.log4j;
   2
   3 import java.util.Date;
   4 import java.util.concurrent.BlockingQueue;
   5
   6 import org.apache.log4j.AppenderSkeleton;
   7 import org.apache.log4j.Level;
   8 import org.apache.log4j.Logger;
   9 import org.apache.log4j.spi.LoggingEvent;
  10 import org.argeo.slc.execution.ExecutionStep;
  11 import org.argeo.slc.runtime.ExecutionThread;
  12 import org.argeo.slc.runtime.ProcessThreadGroup;
  13
  14 /** Not meant to be used directly in standard log4j config */
  15 public class SlcExecutionAppender extends AppenderSkeleton {
  16
  17         private Boolean disabled = false;
  18
  19         private String level = null;
  20
  21         private Level log4jLevel = null;
  22
  23         /** Marker to prevent stack overflow */
  24         private ThreadLocal<Boolean> dispatching = new ThreadLocal<Boolean>() {
  25
  26                 @Override
  27                 protected Boolean initialValue() {
  28                         return false;
  29                 }
  30         };
  31
  32         // private Layout layout = null;
  33         // private String pattern = "%m - %c%n";
  34         private Boolean onlyExecutionThread = false;
  35
  36         public void init() {
  37                 // if (layout != null)
  38                 // setLayout(layout);
  39                 // else
  40                 // setLayout(new PatternLayout(pattern));
  41                 Logger.getRootLogger().addAppender(this);
  42         }
  43
  44         @Override
  45         protected void append(LoggingEvent event) {
  46                 if (disabled)
  47                         return;
  48
  49                 if (dispatching.get())
  50                         return;
  51
  52                 if (level != null && !level.trim().equals("")) {
  53                         if (log4jLevel == null || !log4jLevel.toString().equals(level))
  54                                 try {
  55                                         log4jLevel = Level.toLevel(level);
  56                                 } catch (Exception e) {
  57                                         System.err.println("Log4j level could not be set for level '" + level + "', resetting it to null.");
  58                                         e.printStackTrace();
  59                                         level = null;
  60                                 }
  61
  62                         if (log4jLevel != null && !event.getLevel().isGreaterOrEqual(log4jLevel)) {
  63                                 return;
  64                         }
  65                 }
  66
  67                 // Check whether we are within an executing process
  68                 Thread currentThread = Thread.currentThread();
  69                 if (currentThread.getThreadGroup() instanceof ProcessThreadGroup) {
  70                         if (onlyExecutionThread && !(currentThread instanceof ExecutionThread))
  71                                 return;
  72
  73                         final String type;
  74                         if (event.getLevel().equals(Level.ERROR) || event.getLevel().equals(Level.FATAL))
  75                                 type = ExecutionStep.ERROR;
  76                         else if (event.getLevel().equals(Level.WARN))
  77                                 type = ExecutionStep.WARNING;
  78                         else if (event.getLevel().equals(Level.INFO))
  79                                 type = ExecutionStep.INFO;
  80                         else if (event.getLevel().equals(Level.DEBUG))
  81                                 type = ExecutionStep.DEBUG;
  82                         else if (event.getLevel().equals(Level.TRACE))
  83                                 type = ExecutionStep.TRACE;
  84                         else
  85                                 type = ExecutionStep.INFO;
  86
  87                         ExecutionStep step = new ExecutionStep(event.getLoggerName(), new Date(event.getTimeStamp()), type,
  88                                         event.getMessage().toString());
  89
  90                         try {
  91                                 dispatching.set(true);
  92                                 BlockingQueue<ExecutionStep> steps = ((ProcessThreadGroup) currentThread.getThreadGroup()).getSteps();
  93                                 if (steps.remainingCapacity() == 0) {
  94                                         stdOut("WARNING: execution steps queue is full, skipping step: " + step);
  95                                         // FIXME understand why it block indefinitely: the queue
  96                                         // should be emptied by the logging thread
  97                                 } else {
  98                                         steps.add(step);
  99                                 }
 100                         } finally {
 101                                 dispatching.set(false);
 102                         }
 103                 }
 104         }
 105
 106         public void destroy() throws Exception {
 107                 Logger.getRootLogger().removeAppender(this);
 108         }
 109
 110         public void close() {
 111         }
 112
 113         public boolean requiresLayout() {
 114                 return false;
 115         }
 116
 117         // public void setLayout(Layout layout) {
 118         // this.layout = layout;
 119         // }
 120
 121         /** For development purpose, since using regular logging is not easy here */
 122         static void stdOut(Object obj) {
 123                 System.out.println(obj);
 124         }
 125
 126         // public void setPattern(String pattern) {
 127         // this.pattern = pattern;
 128         // }
 129
 130         public void setOnlyExecutionThread(Boolean onlyExecutionThread) {
 131                 this.onlyExecutionThread = onlyExecutionThread;
 132         }
 133
 134         public void setDisabled(Boolean disabled) {
 135                 this.disabled = disabled;
 136         }
 137
 138         public void setLevel(String level) {
 139                 this.level = level;
 140         }
 141
 142 }