Closing a Connection or Statement object twice should be a no-op

instead of throwing an Exception.

Per report from Victor Sergienko.

src/interfaces/jdbc/org/postgresql/jdbc1/AbstractJdbc1Statement.java

@@ -26,7 +26,7 @@ import java.sql.Timestamp;
 import java.sql.Types;
 import java.util.Vector;
 
-/* $Header: /cvsroot/pgsql/src/interfaces/jdbc/org/postgresql/jdbc1/Attic/AbstractJdbc1Statement.java,v 1.41.2.3 2004/02/03 05:13:55 jurka Exp $
+/* $Header: /cvsroot/pgsql/src/interfaces/jdbc/org/postgresql/jdbc1/Attic/AbstractJdbc1Statement.java,v 1.41.2.4 2004/02/24 13:11:44 jurka Exp $
  * This class defines methods of the jdbc1 specification.  This class is
  * extended by org.postgresql.jdbc2.AbstractJdbc2Statement which adds the jdbc2
  * methods.  The real Statement class (for jdbc1) is org.postgresql.jdbc1.Jdbc1Statement
@@ -84,6 +84,8 @@ public abstract class AbstractJdbc1Statement implements BaseStatement
 
 	private boolean m_useServerPrepare = false;
 
+	private boolean isClosed = false;
+
     // m_preparedCount is used for naming of auto-cursors and must
     // be synchronized so that multiple threads using the same
     // connection don't stomp over each others cursors.
@@ -785,6 +787,10 @@ public abstract class AbstractJdbc1Statement implements BaseStatement
 	 */
 	public void close() throws SQLException
 	{
+		// closing an already closed Statement is a no-op.
+		if (isClosed)
+			return;
+
 		// Force the ResultSet to close
 		java.sql.ResultSet rs = getResultSet();
 		if (rs != null)
@@ -794,6 +800,7 @@ public abstract class AbstractJdbc1Statement implements BaseStatement
 
 		// Disasociate it from us (For Garbage Collection)
 		result = null;
+		isClosed = true;
 	}
 
  	/**

src/interfaces/jdbc/org/postgresql/jdbc2/optional/PooledConnectionImpl.java

@@ -14,7 +14,7 @@ import org.postgresql.PGConnection;
  *
  * @author Aaron Mulder (ammulder@chariotsolutions.com)
  * @author Csaba Nagy (ncsaba@yahoo.com)
- * @version $Revision: 1.7.4.2 $
+ * @version $Revision: 1.7.4.3 $
  */
 public class PooledConnectionImpl implements PooledConnection
 {
@@ -234,12 +234,17 @@ public class PooledConnectionImpl implements PooledConnection
 			{
 				return con == null ? Boolean.TRUE : Boolean.FALSE;
 			}
-			if (con == null)
+			if (con == null && !method.getName().equals("close"))
 			{
 				throw new SQLException(automatic ? "Connection has been closed automatically because a new connection was opened for the same PooledConnection or the PooledConnection has been closed" : "Connection has been closed");
 			}
 			if (method.getName().equals("close"))
 			{
+				// we are already closed and a double close
+				// is not an error.
+				if (con == null)
+					return null;
+
 				SQLException ex = null;
 				if (!con.getAutoCommit())
 				{
@@ -358,12 +363,12 @@ public class PooledConnectionImpl implements PooledConnection
                 return method.invoke(st, args);
             }
             // All the rest is from the Statement interface
-            if (st == null || con.isClosed())
-            {
-                throw new SQLException("Statement has been closed");
-            }
             if (method.getName().equals("close"))
             {
+                // closing an already closed object is a no-op
+                if (st == null || con.isClosed())
+                    return null;
+
                 try {
                     st.close();
                 } finally {
@@ -372,6 +377,10 @@ public class PooledConnectionImpl implements PooledConnection
                 }
                 return null;
             }
+            if (st == null || con.isClosed())
+            {
+                throw new SQLException("Statement has been closed");
+            }
             else if (method.getName().equals("getConnection"))
             {
                 return con.getProxy(); // the proxied connection, not a physical connection

src/interfaces/jdbc/org/postgresql/test/jdbc2/ConnectionTest.java

@@ -10,7 +10,7 @@ import java.sql.*;
  *
  * PS: Do you know how difficult it is to type on a train? ;-)
  *
- * $Id: ConnectionTest.java,v 1.10 2002/10/17 05:33:52 barry Exp $
+ * $Id: ConnectionTest.java,v 1.10.6.1 2004/02/24 13:11:44 jurka Exp $
  */
 
 public class ConnectionTest extends TestCase
@@ -347,4 +347,14 @@ public class ConnectionTest extends TestCase
 			assertTrue(ex.getMessage(), false);
 		}
 	}
+
+	/**
+	 * Closing a Connection more than once is not an error.
+	 */
+	public void testDoubleClose() throws SQLException
+	{
+		Connection con = TestUtil.openDB();
+		con.close();
+		con.close();
+	}
 }

src/interfaces/jdbc/org/postgresql/test/jdbc2/optional/ConnectionPoolTest.java

@@ -12,7 +12,7 @@ import java.io.*;
  * interface to the PooledConnection is through the CPDS.
  *
  * @author Aaron Mulder (ammulder@chariotsolutions.com)
- * @version $Revision: 1.6.4.3 $
+ * @version $Revision: 1.6.4.4 $
  */
 public class ConnectionPoolTest extends BaseDataSourceTest
 {
@@ -131,13 +131,6 @@ public class ConnectionPoolTest extends BaseDataSourceTest
 			}
 			catch (SQLException e)
 			{}
-			try
-			{
-				con.close();
-				fail("Original connection wrapper should be closed when new connection wrapper is generated");
-			}
-			catch (SQLException e)
-			{}
 			con2.close();
 			pc.close();
 		}
@@ -194,13 +187,8 @@ public class ConnectionPoolTest extends BaseDataSourceTest
 			con.close();
 			assertTrue(cc.getCount() == 2);
 			assertTrue(cc.getErrorCount() == 0);
-			try
-			{
+			// a double close shouldn't fire additional events
 				con.close();
-				fail("Should not be able to close a connection wrapper twice");
-			}
-			catch (SQLException e)
-			{}
 			assertTrue(cc.getCount() == 2);
 			assertTrue(cc.getErrorCount() == 0);
 			pc.close();

src/interfaces/jdbc/org/postgresql/test/jdbc2/optional/PoolingDataSourceTest.java

@@ -1,6 +1,7 @@
 package org.postgresql.test.jdbc2.optional;
 
 import java.sql.SQLException;
+import java.sql.Statement;
 import org.postgresql.test.TestUtil;
 import org.postgresql.jdbc2.optional.PoolingDataSource;
 import org.postgresql.jdbc2.optional.BaseDataSource;
@@ -9,7 +10,7 @@ import org.postgresql.jdbc2.optional.BaseDataSource;
  * Minimal tests for pooling DataSource.  Needs many more.
  *
  * @author Aaron Mulder (ammulder@chariotsolutions.com)
- * @version $Revision: 1.1.6.1 $
+ * @version $Revision: 1.1.6.2 $
  */
 public class PoolingDataSourceTest extends BaseDataSourceTest
 {
@@ -96,4 +97,26 @@ public class PoolingDataSourceTest extends BaseDataSourceTest
         {
         }
     }
+
+    /**
+     * Closing a Connection twice is not an error.
+     */
+    public void testDoubleConnectionClose() throws SQLException
+    {
+        con = getDataSourceConnection();
+        con.close();
+        con.close();
+    }
+
+    /**
+     * Closing a Statement twice is not an error.
+     */
+    public void testDoubleStatementClose() throws SQLException
+    {
+        con = getDataSourceConnection();
+        Statement stmt = con.createStatement();
+        stmt.close();
+        stmt.close();
+        con.close();
+    }
 }