Utility class for DB related functionality

1 files changed, 85 insertions, 0 deletions

diff --git a/src/com.gluster.storage.management.gateway/src/com/gluster/storage/management/gateway/utils/DBUtil.java b/src/com.gluster.storage.management.gateway/src/com/gluster/storage/management/gateway/utils/DBUtil.java
new file mode 100644
index 00000000..e224b4cb
--- /dev/null
+++ b/src/com.gluster.storage.management.gateway/src/com/gluster/storage/management/gateway/utils/DBUtil.java
@@ -0,0 +1,85 @@
+/*******************************************************************************
+ * Copyright (c) 2011 Gluster, Inc. <http://www.gluster.com>
+ * This file is part of Gluster Management Console.
+ *
+ * Gluster Management Console is free software; you can redistribute it and/or 
+ * modify it under the terms of the GNU Affero General Public License as published
+ * by the Free Software Foundation; either version 3 of the License, or
+ * (at your option) any later version.
+ *  
+ * Gluster Management Console is distributed in the hope that it will be useful, 
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY
+ * or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU Affero General Public License
+ * for more details.
+ *  
+ * You should have received a copy of the GNU Affero General Public License
+ * along with this program. If not, see
+ * <http://www.gnu.org/licenses/>.
+ *******************************************************************************/
+package com.gluster.storage.management.gateway.utils;
+
+import java.sql.DriverManager;
+import java.sql.SQLException;
+
+import org.apache.derby.jdbc.EmbeddedDriver;
+import org.apache.log4j.Logger;
+
+import com.gluster.storage.management.core.constants.CoreConstants;
+
+/**
+ *
+ */
+public class DBUtil {
+	private static final Logger logger = Logger.getLogger(DBUtil.class);
+	public static void shutdownDerby() {
+		try {
+			// the shutdown=true attribute shuts down Derby
+			DriverManager.getConnection("jdbc:derby:;shutdown=true");
+			
+			// To shut down a specific database only, but keep the
+            // engine running (for example for connecting to other
+            // databases), specify a database in the connection URL:
+            //DriverManager.getConnection("jdbc:derby:" + dbName + ";shutdown=true");
+		} catch (Exception e) {
+			if(e instanceof SQLException) {
+				SQLException se = (SQLException) e;
+				if (((se.getErrorCode() == 50000) && ("XJ015".equals(se.getSQLState())))) {
+					// we got the expected exception
+					logger.info("Derby shut down normally");
+					// Note that for single database shutdown, the expected
+					// SQL state is "08006", and the error code is 45000.
+				} else {
+					// if the error code or SQLState is different, we have
+					// an unexpected exception (shutdown failed)
+					logger.error("Derby did not shut down normally!" + inspectSQLException(se), se);
+				}
+			} else {
+				logger.error("Derby did not shut down normally! [" + e.getMessage() + "]", e);
+			}
+		}
+		// force garbage collection to unload the EmbeddedDriver
+        // so Derby can be restarted
+        System.gc();
+	}
+	
+	/**
+     * Extracts details of an SQLException chain to <code>String</code>.
+     * Details included are SQL State, Error code, Exception message.
+     *
+     * @param e the SQLException from which to print details.
+     */
+    private static String inspectSQLException(SQLException e)
+    {
+        // Unwraps the entire exception chain to unveil the real cause of the
+        // Exception.
+    	String errMsg = "";
+        while (e != null)
+        {
+			errMsg += "\n----- SQLException -----" + CoreConstants.NEWLINE + "  SQL State:  " + e.getSQLState()
+					+ CoreConstants.NEWLINE + "  Error Code: " + e.getErrorCode() + CoreConstants.NEWLINE
+					+ "  Message:    " + e.getMessage();
+            e = e.getNextException();
+        }
+        return errMsg;
+    }
+}