Task 1
Given the following ConnectJ.properties file:
#PropertiesResourceBundle for Connection Properties
CSDriver=COM.cloudscape.core.RmiJdbcDriver
CSURL=jdbc:cloudscape:rmi:jGuru
Set up String variables to access the keys and to hold the returned values. Also set up Strings 1) containing the name of the properties file - ConnectJ, and 2) containing a SELECT statement to get all columns and rows, but omit the table name, which will be obtained and appended later in the program.
Insert the following code:
String sDriver,
sDriverKey = "CSDriver",
sPassword,
sQuery =
"SELECT * FROM ",
srbName = "ConnectJ",
sTable,
sURL,
sURLKey="CSURL",
sUserID;
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Task 2
Access the ResourceBundle and retrieve the driver name and databaseURL.
rbConnect = ResourceBundle.getBundle( srbName );
sDriver = rbConnect.getString( sDriverKey );
sURL = rbConnect.getString( sURLKey );
Task 3
Display a GUI form which requests a userID,password and table name, has a "Connect" button and a textarea. This is done for you. When the button is clicked, in actionPerformed(), verify that a table name was entered ( from jtTable, ) get the userID ( from jtUserID ) and password ( from jpfPassword ) keyed, reset the text area ( jta ) and invoke doConnect().
sTable = jtTable.getText();
if( sTable.equals("") )
{
jta.setText( "Table must have an entry." );
return;
}
sUserID = jtUserID.getText();
sPassword = jpfPassword.getText();
jta.setText( "" );
doConnect();
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Task 4
In doConnect(), the driver is loaded, a Connection obtained and a Statement created as before. Your job: concatenate the query string and table name, then execute the query.
rs = stmt.executeQuery( sQuery + sTable );
Task 5
In doConnect(), a boolean, a StringBuffer and a while( rs.next() loop are provided. Inside the loop, an if( bFirst ) section to determine the first time through the loop is set up. Your job: use ResultSetMetadata to get and display ColumnCount number of ColumnLabels in a single String in the text area jta. Reset the StringBuffer and ensure that this process only happens once per while loop.
rsmd = rs.getMetaData();
iColumnCount = rsmd.getColumnCount();
for( int i = 1; i <= iColumnCount; i++ )
{
sb.append(
rsmd.getColumnLabel( i ) + "\t" );
}
jta.append( sb.toString() + "\n");
sb.replace( 0, sb.length(), "" );
bFirst = false;
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Task 6
In doConnect(), on every pass of the while loop, obtain ColumnCount number of columns for the row using ResultSet.getObject() and concatenate these into a single String. getObject(), as used here, will obtain a String from virtually any type returned from the database. Append the resulting String to the text area jta and reset the StringBuffer.
for( int i = 1; i <= iColumnCount; i++ )
{
sb.append( rs.getObject( i ) + "\t" );
}
jta.append( sb.toString() + "\n");
sb.replace( 0, sb.length(), "" );
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