Attempt to fix OverlappingFileLock Issues, added customizable filelock timeout

Author: Bohn

inspectit-ocelot-agent/src/main/java/rocks/inspectit/ocelot/agent/AgentJars.java

@@ -5,6 +5,7 @@
 import java.io.*;
 import java.nio.channels.FileChannel;
 import java.nio.channels.FileLock;
+import java.nio.channels.OverlappingFileLockException;
 import java.nio.charset.StandardCharsets;
 import java.nio.file.Files;
 import java.nio.file.Path;
@@ -144,7 +145,7 @@ private static Path recycleJarFileWithLock(String resourcePath, Path jarPath) th
 
         try (RandomAccessFile lockFile = new RandomAccessFile(lockPath.toFile(), "rw");
              FileChannel lockChannel = lockFile.getChannel();
-             FileLock lock = acquireLock(lockChannel, 1500, 50)
+             FileLock lock = acquireLock(lockChannel, getJarRecyclingTimeout(), 50)
         ) {
             if (lock == null) throw new IOException("Could not acquire lock for: " + lockPath);
 
@@ -167,9 +168,13 @@ private static FileLock acquireLock(FileChannel lockChannel, long timeout, long
         long end = System.currentTimeMillis() + timeout;
 
         while (System.currentTimeMillis() < end) {
-            FileLock lock = lockChannel.tryLock();
-            if (lock != null) return lock;
-
+            try {
+                FileLock lock = lockChannel.tryLock();
+                if (lock != null) return lock;
+            } catch (OverlappingFileLockException e) {
+                System.err.println("OverlappingFileLock occured." + e);
+                throw new IOException(e);
+            }
             try {
                 Thread.sleep(retryDelay);
             } catch (InterruptedException e) {
@@ -218,6 +223,30 @@ private static boolean isRecyclingEnabled() {
         return "true".equalsIgnoreCase(isRecyclingEnabledValue);
     }
 
+    /**
+     * If the recycling of jars is enabled, the timeout for the recycling/file locking operation can be set.
+     * The value has to be a non-zero non-negative long, if the conditions are not met, it defaults to 3000ms.
+     *
+     * @return long, either the default of 3000ms or the value of the timeout property
+     */
+    private static long getJarRecyclingTimeout() {
+        String recyclingTimeout = null != System.getProperty(AgentProperties.RECYCLE_JARS_TIMEOUT_PROPERTY) ?
+                System.getProperty(AgentProperties.RECYCLE_JARS_TIMEOUT_PROPERTY) : System.getenv(AgentProperties.RECYCLE_JARS_TIMEOUT_PROPERTY);
+
+        final long DEFAULT_RECYCLE_TIMEOUT = 3000;
+
+        if (recyclingTimeout == null) return DEFAULT_RECYCLE_TIMEOUT;
+
+        try {
+            long recyclingTimeoutLong = Long.parseUnsignedLong(recyclingTimeout);
+            if (recyclingTimeoutLong <= 0) throw new NumberFormatException();
+            return recyclingTimeoutLong;
+        } catch (NumberFormatException nfe) {
+            System.err.println("Jar Recycling Timeout property must be a non-negative non-zero long, therefore reverting to default timeout of 3000ms.");
+            return DEFAULT_RECYCLE_TIMEOUT;
+        }
+    }
+
     /**
      * Reads the current agent version from the ocelot-version.info file
      *

inspectit-ocelot-bootstrap/src/main/java/rocks/inspectit/ocelot/bootstrap/AgentProperties.java

@@ -15,6 +15,8 @@ public class AgentProperties {
 
     public static final String RECYCLE_JARS_PROPERTY = "inspectit.recycle-jars";
 
+    public static final String RECYCLE_JARS_TIMEOUT_PROPERTY = "inspectit.recycle-jars-timeout";
+
     public static final String RECYCLE_JARS_ENV_PROPERTY = "INSPECTIT_RECYCLE_JARS";
 
     public static final String INSPECTIT_TEMP_DIR_PROPERTY = "inspectit.temp-dir";
@@ -27,6 +29,7 @@ public class AgentProperties {
     static {
         PROPERTY_NAMES.add(START_DELAY_PROPERTY);
         PROPERTY_NAMES.add(RECYCLE_JARS_PROPERTY);
+        PROPERTY_NAMES.add(RECYCLE_JARS_TIMEOUT_PROPERTY);
         PROPERTY_NAMES.add(INSPECTIT_TEMP_DIR_PROPERTY);
     }