try unregister jdbc

1 files changed, 22 insertions, 0 deletions

diff --git a/src/main/java/com/juick/CrosspostComponent.java b/src/main/java/com/juick/CrosspostComponent.java
index 0b5a5bc2..4e4264cb 100644
--- a/src/main/java/com/juick/CrosspostComponent.java
+++ b/src/main/java/com/juick/CrosspostComponent.java
@@ -36,8 +36,10 @@ import java.net.URL;
 import java.net.URLEncoder;
 import java.security.Key;
 import java.sql.Connection;
+import java.sql.Driver;
 import java.sql.DriverManager;
 import java.sql.SQLException;
+import java.util.Enumeration;
 import java.util.Properties;
 import java.util.UUID;
 import java.util.concurrent.ExecutorService;
@@ -97,6 +99,26 @@ public class CrosspostComponent implements ServletContextListener,  Stream.Strea
 
     @Override
     public void contextDestroyed(ServletContextEvent sce) {
+        // Now deregister JDBC drivers in this context's ClassLoader:
+        // Get the webapp's ClassLoader
+        ClassLoader cl = Thread.currentThread().getContextClassLoader();
+        // Loop through all drivers
+        Enumeration<Driver> drivers = DriverManager.getDrivers();
+        while (drivers.hasMoreElements()) {
+            Driver driver = drivers.nextElement();
+            if (driver.getClass().getClassLoader() == cl) {
+                // This driver was registered by the webapp's ClassLoader, so deregister it:
+                try {
+                    logger.info(String.format("Deregistering JDBC driver %s", driver.toString()));
+                    DriverManager.deregisterDriver(driver);
+                } catch (SQLException ex) {
+                    logger.log(Level.SEVERE, String.format("Error deregistering JDBC driver %s", driver), ex);
+                }
+            } else {
+                // driver was not registered by the webapp's ClassLoader and may be in use elsewhere
+                logger.log(Level.SEVERE, String.format("Not deregistering JDBC driver %s as it does not belong to this webapp's ClassLoader", driver));
+            }
+        }
         executorService.shutdown();
         logger.info("component destroyed");
     }