Go back to old log file rotation code layout a bit, but still only use one thread to gzip all rotated files:

- GZipper class is with FileLogger again and takes either a list of files or a single file
- Log file rotation is done synchronously in the Logging.Runner thread, only gzipping is done in
  a separate thread

src/helma/util/FileLogger.java

@@ -21,6 +21,7 @@ import org.apache.commons.logging.Log;
 import java.io.*;
 import java.text.*;
 import java.util.*;
+import java.util.zip.GZIPOutputStream;
 
 /**
  * An extended Logger that writes to a file and rotates files each midnight.
@@ -79,7 +80,7 @@ public class FileLogger extends Logger implements Log {
                 File archive = rotateLogFile();
                 // gzip rotated log file in a separate thread
                 if (archive != null) {
-                    new Logging.FileGZipper(archive).start();
+                    new GZipper(archive).start();
                 }
             }
             // create a new log file, appending to an existing file
@@ -252,4 +253,50 @@ public class FileLogger extends Logger implements Log {
         super.fatal(parm1, parm2);
     }
 
+     /**
+      * a Thread class that zips up a file, filename will stay the same.
+      */
+     static class GZipper extends Thread {
+         List files;
+         final static int BUFFER_SIZE = 8192;
+
+         public GZipper(List files) {
+             this.files = files;
+             setPriority(MIN_PRIORITY);
+         }
+
+         public GZipper(File file) {
+             files = new ArrayList(1);
+             files.add(file);
+             setPriority(MIN_PRIORITY);
+         }
+
+         public void run() {
+             Iterator it = files.iterator();
+             File file = null;
+
+             while (it.hasNext()) {
+                 try {
+                     file = (File) it.next();
+                     File zipped = new File(file.getAbsolutePath() + ".gz");
+                     GZIPOutputStream zip = new GZIPOutputStream(new FileOutputStream(zipped));
+                     BufferedInputStream in = new BufferedInputStream(new FileInputStream(file));
+                     byte[] b = new byte[BUFFER_SIZE];
+                     int len = 0;
+
+                     while ((len = in.read(b, 0, BUFFER_SIZE)) != -1) {
+                         zip.write(b, 0, len);
+                     }
+
+                     zip.close();
+                     in.close();
+                     file.delete();
+                 } catch (Exception e) {
+                     System.err.println("Error gzipping " + file);
+                     System.err.println(e.toString());
+                 }
+             }
+         }
+     }
+
 }

src/helma/util/Logging.java

@@ -19,7 +19,6 @@ package helma.util;
 import org.apache.commons.logging.*;
 import java.io.*;
 import java.util.*;
-import java.util.zip.GZIPOutputStream;
 
 /**
  *  Implementation of Jakarta Commons LogFactory that supports both
@@ -173,30 +172,32 @@ public class Logging extends LogFactory {
         consoleLog = null;
     }
 
-    static void gzip(File file) {
+    /**
-        final int BUFFER_SIZE = 8192;
+     * Rotate log files on all registered logs
+     */
+    static void rotateLogs() {
+        int nloggers = loggers.size();
+        ArrayList files = new ArrayList(nloggers);
 
-        try {
+        for (int i = nloggers - 1; i >= 0; i--) {
-            File zipped = new File(file.getAbsolutePath() + ".gz");
+            FileLogger log = (FileLogger) loggers.get(i);
-            GZIPOutputStream zip = new GZIPOutputStream(new FileOutputStream(zipped));
-            BufferedInputStream in = new BufferedInputStream(new FileInputStream(file));
-            byte[] b = new byte[BUFFER_SIZE];
-            int len = 0;
 
-            while ((len = in.read(b, 0, BUFFER_SIZE)) != -1) {
+            try {
-                zip.write(b, 0, len);
+                File file = log.rotateLogFile();
+                if (file != null) {
+                    files.add(file);
+                }
+            } catch (IOException io) {
+                System.err.println("Error rotating log " + log.getName() + ": " +
+                                    io.toString());
             }
+        }
 
-            zip.close();
+        if (!files.isEmpty()) {
-            in.close();
+            new FileLogger.GZipper(files).start();
-            file.delete();
-        } catch (Exception e) {
-            System.err.println("Error gzipping " + file);
-            System.err.println(e.toString());
         }
     }
 
-
     /**
      * Returns the timestamp for the next Midnight
      *
@@ -215,8 +216,6 @@ public class Logging extends LogFactory {
         return cal.getTime().getTime();
     }
 
-
-
     /**
      *  The static runner class that loops through all loggers.
      */
@@ -230,7 +229,7 @@ public class Logging extends LogFactory {
                 long now = System.currentTimeMillis();
 
                 if (nextMidnight < now) {
-                    new LogRotator().start();
+                    rotateLogs();
                     nextMidnight = nextMidnight();
                 }
 
@@ -264,58 +263,5 @@ public class Logging extends LogFactory {
         }
 
     }
-
-    /**
-     * Log rotator thread calls rotateLogFiles on all
-     */
-    static class LogRotator extends Thread {
-
-        public void run() {
-
-            FileLogger[] logs = (FileLogger[]) loggers.toArray(new FileLogger[0]);
-
-            ArrayList archives = new ArrayList();
-
-            for (int i = 0; i < logs.length; i++) {
-                try {
-                    File archive = logs[i].rotateLogFile();
-                    if (archive != null) {
-                        archives.add(archive);
-                    }
-                } catch (IOException io) {
-                    System.err.println("Error rotating log " + logs[i].getName() + ": " +
-                                        io.toString());
-                }
-            }
-
-            // reduce thread priority for zipping
-            setPriority(MIN_PRIORITY);
-            Iterator it = archives.iterator();
-            while (it.hasNext()) {
-                gzip((File) it.next());
-            }
-
-        }
-
-    }
-
-    /**
-     * Utility thread class to gzip a file in a separate thread
-     */
-    static class FileGZipper extends Thread {
-
-        File file;
-
-        FileGZipper(File file) {
-            this.file = file;
-        }
-
-        public void run() {
-            // reduce thread priority for zipping
-            setPriority(MIN_PRIORITY);
-            gzip(file);
-        }
-    }
-
 }