Modify driver connection api

src/qir/driver/DBDriver.java

@@ -8,8 +8,17 @@ import qir.ast.data.*;
 
 public abstract class DBDriver {
     protected Connection conn;
+    protected ConnectionData connData;
 
-    public abstract void openConnection(ConnectionData connData) throws SQLException;
+    public void openConnection() throws SQLException {
+        openConnection(connData);
+    }
+
+    public void openConnection(ConnectionData data) throws SQLException {
+        if (conn != null)
+            closeConnection();
+        connData = data;
+    }
 
     public void closeConnection() throws SQLException {
         if (conn == null)
@@ -18,5 +27,13 @@ public abstract class DBDriver {
         conn = null;
     }
 
+    public boolean isConnOpen() {
+        return conn != null;
+    }
+
+    public void setConnectionData(ConnectionData connData) {
+        this.connData = connData;
+    }
+
     public abstract QIRList run(QIRNode root);
 }
\ No newline at end of file

src/qir/driver/OracleDriver.java

@@ -18,8 +18,7 @@ import qir.driver.ConnectionData;
 public class OracleDriver extends DBDriver {
     @Override
     public void openConnection(ConnectionData data) throws SQLException {
-        if (conn != null)
-            closeConnection();
+        super.openConnection(data);
         String connString = "jdbc:oracle:thin:@" + data.serverName + ":" + data.portNumber + ":" + data.sid;
         OracleDataSource ods = new OracleDataSource();
         ods.setUser(data.userName);

src/qir/driver/PostgreSQLDriver.java

@@ -17,9 +17,8 @@ import qir.util.QIRPrintVisitor;
  */
 public class PostgreSQLDriver extends DBDriver {
     @Override
-    public void openConnection(ConnectionData connData) throws SQLException {
-        if (conn != null)
-            closeConnection();
+    public void openConnection(ConnectionData data) throws SQLException {
+        super.openConnection(data);
         String url = "jdbc:postgresql://" + connData.serverName + ":" + connData.portNumber + "/" + connData.sid;
         Properties props = new Properties();
         props.setProperty("user", connData.userName);