1 files changed, 165 insertions, 0 deletions
diff --git a/das-java/tags/1.0-incubating-beta1/samples/dbconfig/src/main/java/org/apache/tuscany/das/rdb/dbconfig/DBConnectionHelper.java b/das-java/tags/1.0-incubating-beta1/samples/dbconfig/src/main/java/org/apache/tuscany/das/rdb/dbconfig/DBConnectionHelper.java
new file mode 100644
index 0000000000..55f54f8f69
--- /dev/null
+++ b/das-java/tags/1.0-incubating-beta1/samples/dbconfig/src/main/java/org/apache/tuscany/das/rdb/dbconfig/DBConnectionHelper.java
@@ -0,0 +1,165 @@
+/*
+ * Licensed to the Apache Software Foundation (ASF) under one
+ * or more contributor license agreements.  See the NOTICE file
+ * distributed with this work for additional information
+ * regarding copyright ownership.  The ASF licenses this file
+ * to you under the Apache License, Version 2.0 (the
+ * "License"); you may not use this file except in compliance
+ * with the License.  You may obtain a copy of the License at
+ * 
+ *   http://www.apache.org/licenses/LICENSE-2.0
+ * 
+ * Unless required by applicable law or agreed to in writing,
+ * software distributed under the License is distributed on an
+ * "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
+ * KIND, either express or implied.  See the License for the
+ * specific language governing permissions and limitations
+ * under the License.    
+ */
+
+package org.apache.tuscany.das.rdb.dbconfig;
+
+import java.sql.Connection;
+import java.sql.DriverManager;
+import java.sql.SQLException;
+
+import javax.naming.InitialContext;
+import javax.naming.NamingException;
+import javax.sql.DataSource;
+
+import org.apache.log4j.Level;
+import org.apache.log4j.Logger;
+
+public class DBConnectionHelper {
+	private static final Logger logger = Logger.getLogger(DBConnectionHelper.class);
+	
+	protected DBConnectionHelper(){
+        if(logger.isDebugEnabled()) {
+            logger.log(Level.DEBUG, "DBConnectionHelper()");
+        }
+	}
+    
+    /**
+     * Basic validation of Config for connection information and call to 
+     * connection helper to establish database connection. Connection using 
+     * DriverManager or DataSource are supported.
+     *
+     */
+    public static Connection createConnection(ConnectionInfo connectionInfo) {
+        if (logger.isDebugEnabled()) {
+            logger.log(Level.DEBUG, "DBConnectionHelper.createConnection(ConnectionInfo)");
+        }
+        
+        if (connectionInfo == null || 
+            (connectionInfo.getDataSource() == null && connectionInfo.getConnectionProperties() == null)) {
+            throw new RuntimeException("No connection has been provided and no data source has been specified");
+        }
+
+        if(connectionInfo.getDataSource() != null && connectionInfo.getConnectionProperties() != null){
+            throw new RuntimeException("Use either dataSource or ConnectionProperties. Can't use both !");
+        }
+        
+        Connection connection = null;
+        
+        if(connectionInfo.getConnectionProperties() != null){
+            connection = initializeDriverManagerConnection(connectionInfo);
+        }else{
+            connection = initializeDatasourceConnection(connectionInfo);
+        }
+        
+        return connection;
+        
+    }
+    /**
+     * Initializes a DB connection on a managed environmet (e.g inside Tomcat)
+     */
+	private static Connection initializeDatasourceConnection(ConnectionInfo connectionInfo){
+        if (logger.isDebugEnabled()) {
+            logger.log(Level.DEBUG, "DBConnectionHelper.initializeDatasourceConnection(ConnectionInfo)");
+        }
+        
+        InitialContext ctx;
+        Connection connection;
+        
+        try {
+            ctx = new InitialContext();
+        } catch (NamingException e) {
+            throw new RuntimeException(e);
+        }
+        try {
+            DataSource ds = (DataSource) ctx.lookup(connectionInfo.getDataSource());
+            try {
+                connection = ds.getConnection();
+                if (connection == null) {
+                    throw new RuntimeException("Could not obtain a Connection from DataSource");
+                }
+                connection.setAutoCommit(true);
+                
+            } catch (SQLException e) {
+                throw new RuntimeException(e);
+            }
+        } catch (NamingException e) {
+            throw new RuntimeException(e);
+        }
+
+        if( logger.isDebugEnabled()) {
+            logger.log(Level.DEBUG, "DBConnectionHelper.initializeDatasourceConnection() exit");
+        }
+        return connection;
+    }
+    
+    /**
+     * Initialize a DB connection on a J2SE environment
+     * For more info, see http://java.sun.com/j2se/1.3/docs/guide/jdbc/getstart/drivermanager.html
+     */
+	private static Connection initializeDriverManagerConnection(ConnectionInfo connectionInfo) {
+		if (logger.isDebugEnabled()) {
+		    logger.log(Level.DEBUG, "DBConnectionHelper.initializeDriverManagerConnection(ConnectionInfo)");
+        }
+    	
+        if (connectionInfo.getConnectionProperties() == null) {
+            throw new DataSourceInitializationException("No existing context and no connection properties");
+        }
+
+        if (connectionInfo.getConnectionProperties().getDriverClass() == null) {
+            throw new DataSourceInitializationException("No jdbc driver class specified!");
+        }
+
+        Connection connection;
+        
+        try {
+            //initialize driver and register it with DriverManager
+            Class.forName(connectionInfo.getConnectionProperties().getDriverClass());
+            
+            //prepare to initialize connection
+            String databaseUrl = connectionInfo.getConnectionProperties().getDatabaseURL();
+            String userName = connectionInfo.getConnectionProperties().getUserName();
+            String userPassword = connectionInfo.getConnectionProperties().getPassword();
+            int loginTimeout = connectionInfo.getConnectionProperties().getLoginTimeout();
+            
+            DriverManager.setLoginTimeout(loginTimeout);
+            if( (userName == null || userName.length() ==0) && (userPassword == null || userPassword.length()==0) ){
+                //no username or password suplied
+                connection = DriverManager.getConnection(databaseUrl);
+            }else{
+                connection = DriverManager.getConnection(databaseUrl, userName, userPassword);
+            }
+            
+            if(connection == null){
+                throw new DataSourceInitializationException("Error initializing connection : null");
+            }
+            
+            connection.setAutoCommit(true);
+        }catch(ClassNotFoundException cnf){
+            throw new DataSourceInitializationException("JDBC Driver '" + connectionInfo.getConnectionProperties().getDriverClass() + "' not found", cnf);
+        }catch(SQLException sqle){
+            throw new DataSourceInitializationException(sqle.getMessage(), sqle);
+        }
+        
+        if (logger.isDebugEnabled()) {
+            logger.log(Level.DEBUG, "DBConnectionHelper.initializeDriverManagerConnection() exit");
+        }
+        
+        return connection;
+    }
+}