The interface CloseListener has a new method 'remove' that is called when the trigger is dropped.

h2/src/main/org/h2/api/CloseListener.java

@@ -22,5 +22,12 @@ public interface CloseListener {
      * @throws SQLException
      */
     void close() throws SQLException;
+    
+    /**
+     * This method is called when the trigger is dropped.
+     * 
+     * @throws SQLException
+     */
+    void remove() throws SQLException;
 
 }

h2/src/main/org/h2/api/Trigger.java

@@ -33,19 +33,14 @@ public interface Trigger {
      * This method is called by the database engine once when initializing the
      * trigger.
      * 
-     * @param conn
-     *            a connection to the database
-     * @param schemaName
-     *            the name of the schema
-     * @param triggerName
-     *            the name of the trigger used in the CREATE TRIGGER statement
-     * @param tableName
-     *            the name of the table
-     * @param before
-     *            whether the fire method is called before or after the
+     * @param conn a connection to the database
+     * @param schemaName the name of the schema
+     * @param triggerName the name of the trigger used in the CREATE TRIGGER
+     *            statement
+     * @param tableName the name of the table
+     * @param before whether the fire method is called before or after the
      *            operation is performed
-     * @param type
-     *            the operation type: INSERT, UPDATE, or DELETE
+     * @param type the operation type: INSERT, UPDATE, or DELETE
      */
     void init(Connection conn, String schemaName, String triggerName, String tableName, boolean before, int type) 
         throws SQLException;
@@ -53,14 +48,12 @@ public interface Trigger {
     /**
      * This method is called for each triggered action.
      * 
-     * @param conn
-     *            a connection to the database
-     * @param oldRow
-     *            the old row, or null if no old row is available (for INSERT)
-     * @param newRow
-     *            the new row, or null if no new row is available (for DELETE)
-     * @throws SQLException
-     *             if the operation must be undone
+     * @param conn a connection to the database
+     * @param oldRow the old row, or null if no old row is available (for
+     *            INSERT)
+     * @param newRow the new row, or null if no new row is available (for
+     *            DELETE)
+     * @throws SQLException if the operation must be undone
      */
     void fire(Connection conn, Object[] oldRow, Object[] newRow) throws SQLException;
     

h2/src/main/org/h2/schema/TriggerObject.java

@@ -285,6 +285,11 @@ public class TriggerObject extends SchemaObjectBase {
     public void removeChildrenAndResources(Session session) throws SQLException {
         table.removeTrigger(this);
         database.removeMeta(session, getId());
+        if (triggerCallback != null) {
+            if (triggerCallback instanceof CloseListener) {
+                ((CloseListener) triggerCallback).remove();
+            }
+        }
         table = null;
         triggerClassName = null;
         triggerCallback = null;