How to code an external Java client (outside of the SilverStream development environment) that accesses the SilverStream Server to populate a JTable with rows of data.
See the chapter on writing external Java clients in the Programmer's Guide |
For example, here's a DSO named dsoProductPassthru that provides access to a database table named product:
To learn about creating DSOs, see the chapter on using data source business objects in the Programmer's Guide.
To learn about the SilverStream API and how to configure your external development environment to use it, see the chapter on coding Java for SilverStream applications in the Programmer's Guide.
To learn about using the SilverStream API in your client classes and configuration requirements when deploying those classes, see the chapter on writing external Java clients in the Programmer's Guide.
Here's a class that provides a basic implementation of this technique.
Source code
package extjtech;
import java.awt.*;
import java.awt.event.*;
import java.io.*;
import javax.swing.*;
import javax.swing.table.JTableHeader;
import com.sssw.rt.util.*;
// The ExtJTable class shows how you can access a SilverStream
// server from an external Java client. It includes an example
// of populating a JTable with data from a SilverStream server
// object.
public class ExtJTable {
// Instance variables for the ExtJTable class.
JTable table;
JTableHeader thead;
JScrollPane scrollpane;
JFrame frame;
// These instance variables are for the SilverStream
// objects used by the ExtJTable class.
AgrServerSession session;
AgrData appdata;
AgoRowCursorTableModel agmodel;
// Constructor for the ExtJTable class. It does the following:
// * Connects to a SilverStream server
// * Accesses the appropriate data
// * Loads the data into a JTable
// * Displays the JTable in a window (JFrame)
//
// It takes 3 arguments:
// 1 SilverStream server host
// myserver
// 2 SilverStream db & data source object
// mydb:com.myorg.data.dsoMyPassthru
// 3 Application title
// My Application Title
public ExtJTable(String s3serverhost,
String s3dsolocation,
String apptitle) {
try {
// Initialize the SilverStream runtime environment. Do
// this if you need to specify a login handler for the
// SilverStream server to call back when it requires user
// authentication. (The login handler is a class that you
// code and instantiate.)
AgRuntime.init(new LoginHandlerDlg());
// Connect to the appropriate SilverStream server. This
// establishes a server session (represented by an instance
// of AgrServerSession).
//
// The following example connects via HTTP. In this case,
// you wouldn't use RMI-IIOP (the connectRMI method),
// because it doesn't support DSO access.
session = AgRuntime.connect(s3serverhost);
// Create an instance of AgrData (to represent the cache of
// data you want to work with).
appdata = new AgrData();
// Initialize the AgrData by passing it the AgrServerSession.
appdata.init(session);
// Specify the data source for the AgrData. In this case,
// it is a pass-through DSO.
appdata.setDataSource(s3dsolocation);
// Invoke the DSO to get the data for the AgrData.
appdata.invokeQuery(null);
// Create a model that a JTable can use to access the
// data in the AgrData. You can do this with an instance
// of AgoRowCursorTableModel.
agmodel = new AgoRowCursorTableModel(appdata);
// Create a JTable instance and bind it to that model.
table = new JTable(agmodel);
// Format the JTable.
table.setRowHeight(10);
table.setIntercellSpacing(new Dimension(8, 8));
thead = table.getTableHeader();
thead.setFont(new Font("Sans Serif", Font.BOLD, 14));
table.setFont(new Font("Sans Serif", Font.PLAIN, 11));
table.setPreferredScrollableViewportSize(new Dimension(500, 300));
// Create a scroll pane and add the JTable to it.
scrollpane = new JScrollPane(table);
// Create a JFrame instance for the application's window.
frame = new JFrame(apptitle);
// Add the scroll pane to the frame.
frame.getContentPane().add(scrollpane, BorderLayout.CENTER);
// Add an event handler to close the SilverStream server
// session when a user closes the window.
frame.addWindowListener(new WindowAdapter() {
public void windowClosing(WindowEvent e) {
session.close();
System.exit(0);
}
});
// Finish setting up the frame, then show it.
frame.pack();
frame.setVisible(true);
}
catch (Exception e) {
System.out.println("Application error in ExtJTable");
e.printStackTrace();
System.exit(0);
}
}
// Main method (used for application startup).
public static void main(String[] args) {
if (args.length < 3) {
// Make sure all of the required command-line args
// have been provided to the application. If not,
// display an error message and terminate.
JFrame errframe = new JFrame();
JOptionPane.showMessageDialog(errframe,
"Required arguments:\n\n" +
"1 SilverStream server host\n" +
"2 SilverStream db & data source object\n" +
"3 Application title\n\n" +
"Example:\n\n" + "java extjtech.ExtJTable " +
"myserver " +
"mydb:com.myorg.data.dsoMyPassthru " +
"\"My Application Title\"",
"Missing Command-Line Arguments",
JOptionPane.ERROR_MESSAGE);
System.exit(0);
}
else {
// Get the command-line args so the application can
// pass them to the ExtJTable constructor.
String s3serverhost = args[0];
String s3dsolocation = args[1];
String apptitle = args[2];
// Create an instance of ExtJTable. This executes the
// constructor for the class, which then accesses the
// SilverStream server and displays the result.
ExtJTable extjtable = new ExtJTable(s3serverhost,
s3dsolocation,
apptitle);
}
}
}
When this class runs, it retrieves rows of data from the DSO, then populates the JTable with them.
