Application Techniques




Core Programming Techniques



Casting an Object to an Integer
Casting an Object to a String
Casting an Object to a Date

Converting Data Types

Converting a String to an int
Converting an int to a String
Converting a String to a Date
Converting a Date to a String

Setting Colors

Setting a default color choice in a list box
Handling a user selection from the list box
Handling red, green, and blue sliders
Making the color change

Setting Fonts

Setting a default font name, size, and style in list boxes
Handling a user selection from the font name list box
Handling a user selection from the font size list box
Handling a user selection from the font style list box
Making the font change

Using Hashtables

Creating a Hashtable
Adding data to a Hashtable
Retrieving a value from a Hashtable with a key
Removing selected data from a Hashtable
Clearing an entire Hashtable

Using Reflection

Getting the name of a selected class
Getting a class
Getting the class methods
Getting the class properties
Getting the constructors
Displaying the class methods, properties, and constructors
Getting a superclass and displaying its name

Using Multidimensional Arrays

Using an array of labels to contain display characters
Setting the array element specified by the user
Obtaining array values to check for a winning pattern
Using a timer before generating a move

Validating with String Pattern Matching

Walking through the overall matching process
Comparing strings by length
Comparing strings character by character
Checking for uppercase and lowercase characters
Checking for letter characters
Checking for digit characters
Checking for letter or digit characters
Checking for the any-character wildcard
Checking for a character match

Using Utility-Class Methods

Creating a utility class
Calling a method of the utility class

Using JavaBeans on Forms

Adding a JavaBean to a form
Modifying the properties of a JavaBean
Displaying the selected date in a text field

Data Access Techniques

Data source objects
Oracle access

Using an executeSQL DSO

Invoking the DSO and passing the SQL statement
Executing the SQL on the database

Using a setResultSet DSO

Objects and data flow
Invoking the DSO and displaying data
Code for the retrieveOrders() method
Instantiating and setting the Java ResultSet
Code for the invokeQuery event
Implementing the Java ResultSet
Code for the executeQuery() method
Code for the next() method

Using a setDataSource DSO

Objects and data flow
Invoking the DSO
Instantiating and setting the AgiDataSource
Implementing AgiDataSource
Implementing AgiBandDescriptor
Extending AgoDataUpdateRequest
Extending AgoDataUpdateRow
Implementing AgiTransactionHandle

Importing a Comma-Delimited File into a Database Table

Objects used in this technique
Data flow
Invoking the business object
Invoking the data source object
Importing the file

Exporting a Database Table to a Formatted File

Objects used in this technique
Data flow
Invoking the servlet
Invoking the data source object
Returning the generated file
Generating the file

Publishing Data Between Databases

Objects used in this technique
Data flow
Passing data to the invoked business object
Invoking the data source object
Copying the data to the destination table

Developing a DSO for Use by Multiple Clients

The data source object (dsoEditTableData)
Objects used in this technique
Calling the data source object
Data flow
Coding the data source object
Implementing the AgiDataSource

Accessing Blobs in Oracle

Accessing Clobs in Oracle

Calling an Oracle PLSQL Function Returning a Cursor

Handling Data Concurrency Errors

Catching concurrency errors when updating changes
Refreshing the screen with the latest data

Dynamically Binding Controls to Data

Creating a control that accesses an independent data set
Binding the property of a text field to a data source property
Invoking the data source object

HTML Client Techniques

Basic techniques
Page flow and state management
HTML-based views
Page beans
JavaServer Pages

Altering Page Controls

Doing Basic Data Navigation and Manipulation

Manipulating Lists

Adjusting an empty list's size
Moving items to the selected list
Moving items to the deselected list
Displaying selected items as text in a dialog box

Programming Page Events

Setting Response Headers, Form Tags, and Body Tags

Controlling Page Flow Using the Session Object

Walking through the flow scenario
Setting a session value
Removing a session value
Redirecting an HTTP request to another URL
Redirecting an HTTP request upon page loading
Redirecting the HTTP request to the first page
Writing the error message servlet

Implementing Persistent Session-Level Failover

Setting up the application
Using the persistent state manager on a page
Getting a reference to the object
Reading and writing state data
Implementing a store manager
Editing the PersistentSession.props file

Sharing Page State Using the Session Object

Confirming a Request before Submitting it to the Server

Adding JavaScript to a page
Writing JavaScript for a button click
Handling a submit request

Displaying Hover-Sensitive Images

Writing hover code in line
Writing hover code in a function

Dynamically Changing Styles

Implementing Tabs with JavaScript and DHTML

Setting up
Coding the tabs

Manipulating Documents and Windows with JavaScript

Switching the document in a window
Opening a new window
Writing to the document in a window
Passing information between windows

Manipulating Page Controls with JavaScript

Coding it in plain HTML and JavaScript
Coding it in SilverStream

Manipulating Strings with JavaScript

Replacing strings
Inserting strings
Extracting strings

Opening and Closing Windows Using JavaScript

Getting user-specified window features
Using openWindow(url, window, features)
Using openWindow(url, window, features, params)
Using openWindow(url, window, features, query, orderby)
Applying request information to the page in the window
Closing the window

Recognizing your Browser

Approach 1: Getting the appName and appVersion
Approach 2: Getting the userAgent

Using the AgpScriptHelper Object

Validating Control Values

Validating Data Entry with JavaScript

Coding it in plain HTML and JavaScript
Coding it in SilverStream

Building a Master/Detail Page

Specifying the master Orders data view
Specifying the Order Details data view
Specifying the total fields
Navigating to the first record
Navigating to the previous record
Navigating to the next record
Navigating to the last record
Initiating find mode
Completing the find request
Performing the Click event to bring up details

Building a Matrix Style Report Using an AgoVectorRowCursor

Declaring variables
Creating the AgoVectorRowCursor
Retrieving the data

Displaying Images in a Data View

Setting up
Associating a database with the page
Creating the data view control
Creating the label control
Setting the label to raw HTML mode
Testing the page

Updating Rows in a View Using a Dialog

Binding controls in separate pages to the same database
Invoking the update dialog
Updating rows from the update dialog

Using Page Beans

Forcing Access through HTTPS

Using JavaServer Pages with SilverStream

Setting up
Coding the JSP pages
Source for date.jsp
Source for include.jsp
Coding the JavaBeans components
Source for
Source for
Coding the deployment XML file
Creating the batch file to deploy the JAR
Deploying and testing the JSP pages

Broadcasting Events between Subpages

Adding code to the parent page
Adding code to the list page
Adding code to the details page
Defining the listener interface
Defining the event utility class

Graphing Data Using a Servlet

Loading the image from the servlet
Importing the Acme classes into the servlet
Coding the service method on the servlet
Creating the graph

Graphing Data Using a Servlet that Calls a JavaBean

Loading the image from the servlet
Importing the Acme and KLG classes into the servlet
Instantiating the JavaBean
Coding the service method on the servlet
Creating the graph

Sending E-Mail Asynchronously

Using an Invisible Tab Control to Create a Multi-Page Look

Setting up the page
Adding code to the Back button
Adding code to the Next button

Using File Attachments on Pages

Java Client Techniques

General techniques for controls
Version 3 Swing-based controls
Version 2 AWT-based controls
Java-based views
Dialogs and subforms
Keystrokes and drawing
External Java clients

Validating Data Entry in the Form and Its Controls

Validation for individual fields
Finishing the validation process for controls
Global validation for the form

Implementing Context-Sensitive Help

Changing the help information for a control
Implementing a custom help display

Using File Attachments on Forms

Uploading a new file into the database
Downloading content from the database as a file
Saving modified content to the database

Using Timers

Starting the timer control
Stopping the timer control

Obtaining the Control with Focus

Basic steps for adding a focus listener
Adding an interface
Adding the listener
Processing the focus event and getting the control name
Removing the listener

Instantiating Bound Controls Dynamically

Changing the data source for an AgcData control
Retrieving the data
Adding controls dynamically
Deleting controls

Extending a SilverStream Control

Creating a subclassed control
Adding the constructor
Building the JAR file
Adding the control to a form
Responding to mouse events

Adding a Listener to a Form Control

Adding a listener

Implementing a Nested Layout

Creating a custom layout manager

Implementing a Custom Insert Image Dialog for the HTML Edit Control

Hiding and showing controls
Using the FileAttachment control to get an image file from disk
Passing the image information back to the HTMLEditControl

Swing Sampler: Using an Assortment of Swing Controls

Creating the controls
Creating the split pane and its contents
Creating the toolbar
Getting a button image
Initializing and adding a button
Finishing the layout
Loading data in the AgcJTable control
Opening a file and displaying it in the editor pane
Reading the file

Using the JCheckBox Control

Getting the control state

Using the JList Control

Getting the string and int values of a selected row

Using the JProgressBar Control

Specifying the control's size and position
Selecting colors
Using the timer
Responding to changes in the progress bar's value

Using the JRadioButton Control

Getting the control state

Using the JSlider Control

Initializing form controls with slider settings
Changing the slider's appearance and parameters
Setting the slider value
Implementing the stateChanged event
Executing a SQL statement

Using the JSpinner Control

Getting the value of a spinner control
Decrementing or incrementing the spinner value

Using the JTable Control

Importing the Swing table package
Initializing form controls with table defaults
Loading the table with data
Getting values from controls and changing the table appearance
Changing a color
Getting a slider value
Getting a checkbox value
Responding to the combo box
Adding the column sorting feature
Allowing column reordering

Using the JTextArea Control

Getting and setting a string in a text area
Appending a string to a string in a text area
Getting and displaying selected text in a dialog box

Using the JTextField Control

Getting and setting a string value for a text field
Getting and setting an integer value for a text field
Getting and setting a date value for a text field

Programming Swing Tree Controls

Importing the Swing tree package
treeLoaded control: populating nodes from static values during setup
treeExpandable control: populating nodes on demand
Adding a TreeWillExpandListener
Allowing children for the first-level values
Populating the hashtable with data for the child nodes
Adding child nodes in the treeWillExpand event
treeRowCursor control: populating a tree from database tables
Using loadFromRowCursor()
Customizing the root node
Populating the second level from an AgcData control

Specifying a Pluggable Look and Feel

Getting the look and feel settings for the form
Changing the look and feel of the form

Using Choice Controls and Combo Boxes

Getting the value of a selected row in a choice control
Getting the value of a selected row in a combo box

Using Several Images from a Single File on an Image Button

Specifying a portion of an image in the Property Inspector
Dynamically changing image properties of an image button

Using Text Buttons

Changing a text button label programmatically
Simulating a clicked event on a text button

Using Tree Controls

Creating and loading the tree control
Expanding a node on the tree control
Collapsing a node on the tree control
Getting and setting text on a selected node
Adding a node to the tree control
Removing a node from the tree control
Finding a node on the tree control
Getting node and parent data from a selected node

Manipulating Views

Setting a default department in the choice control
Handling a user selection from the choice control
Handling the rate percentage slider
Making the salary rate change
Saving the changes

Dynamically Formatting Data in Views

Adding a data control to a form
Defining column formats for a band format
Adding band formats to a view format
Initializing a view with dynamic data and a view format

Adding and Deleting Rows with Row Cursors

Associating a vector and a row cursor
Adding a row to a vector
Deleting a row from a vector
Updating the view

Constructing a Hierarchical View Using AgoTreeDataManager

How this technique is organized
Creating an AgcView with hierarchical columns
Creating a multinode AgoTreeDataManager

Displaying Dialogs

Displaying a message dialog
Displaying an OK/Cancel dialog
Displaying a Yes/No dialog
Displaying a Yes/No/Cancel dialog
Displaying an error message dialog
Displaying a form for editing data in a dialog

Opening Subforms

Opening various kinds of subforms from a parent form
Firing a custom event back to the parent form
Directly manipulating controls on the parent form

Using Subforms to Share Globals among Forms

Creating a subform to contain globals
Getting a reference to a single subfrmCircle instance
Accessing a single subfrmCircle instance from any subfrmGlobals instance
Launching subfrmGlobals forms

Basic Code for a MenuBar and Popup Menu

Calling the methods in the FormActivate event
Building the menubar
Building the popup menu
Displaying the popup menu
Responding to standard menu selections
Responding to check box menu selections

Building Menus and Generating Menu Code

Creating a tree menu
Creating a popup menu for editing the tree menu
Implementing the popup menu's operations
Obtaining generated code for the formActivate() and menuItemSelected() methods

Building a Text Editor with Menus

Creating menus
Displaying a popup menu for browser applications
Handling menu item selections
Performing the Copy clipboard operation
Performing the Cut clipboard operation
Perfoming the Paste clipboard operation

Processing Keystrokes

Getting the pressed key and modifiers
Sorting rows by column entry

Creating Animations

Setting up images and user-input controls
Implementing animation with the switch statement

Accessing Data from External Java Clients

Setting up
Coding the client
Running the client

Providing Data to JTables in External Java Clients

Setting up
Coding the client
Running the client

Calling EJB Session Beans from External Java Clients

Setting up
Coding the client
Running the client

Invoking Business Objects from External Java Clients

Setting up
Coding the client
Running the client

Administering the Server from External Java Clients

Setting up
Coding the client
Running the client

Handling User Authentication from External Java Clients

Designing your login handler
Coding a basic login handler
How it works
Coding a graphical login handler
How it works

Enterprise JavaBean Techniques

Using EJB Environment Properties

Using environment properties
Specifying environment variables in the deployment descriptor
Looking up the property at runtime

Using EJB Resource References

Specifying resource references in the deployment descriptor
Using the JAR Designer to map resources
Using SilverCmd to map the resources
Looking up the resource at runtime
Resource scoping

Using EJB Bean References

Specifying bean references in the deployment descriptor
How the SBBankATM finds bean references

Using EJB Session Beans to Control an Entity Bean's Transaction Scope

Writing a session bean with bean-demarcated transactions
Using the Java Transaction API
A closer look at the BankDemo's transactional methods
Making sure the entity beans use the correct transaction context
Specifying session bean transaction management type

Writing EJB Expression-Style Finder Methods

Writing an expression-based finder method
Specifying the expression using the JAR Designer
Specifying the expression using the SilverCmd DeployEJB XML file

Writing EJB Method-Style Finder Methods

Writing method-style finders
Specifying method-style finders using the JAR Designer
Specifying method-style finders in the SilverCmd DeployEJB XML file

Writing EJB Applications Using Accessors

How accessor components work
How to write accessor applications
Writing the entity bean
Writing the session bean
Writing the accessor class
Writing the accessor client
Writing a form or page that uses accessors
Where to get more information

Triggered Business Object Techniques


Serializing and Deserializing Business Objects

Objects in this example
Using ObjectInputStream to serialize data
Using AgoObjectInputStream to deserialize data
A page that calls the objects

Using a Session Object to Share Information

Getting the session id from an invoked object
Passing session values to the invoked object
Setting the session values on the subform
Handling requests from multiple callers

Using an Invoked Object to Cache Data

Using the serverStarted event to cache data
Invoking the object and managing the result
Coding the handlePageException
Resetting the last-modified date
Using the invoked object to determine if data is current
Setting the data modified flag
Getting and storing the data in the Vector variable

Developing a Servlet that Uses Caching

How this example works
Class member variables
Caching data when the server is started
Determining if session data has been updated
Managing the cached data in the servlet

Using a Servlet to Build an HTML Page

Using the HTML helper object in the servlet
Creating helper methods for HTML formatting

Using a Servlet to Retrieve Data

Creating a business object with a servlet trigger
Adding a dataset to the business object
Coding the servlet to query and return the result

Administration Techniques

Enumerating Server Objects

Getting a server
Enumerating databases on the server
Enumerating other objects on the server

Enumerating Security Providers, Users, and Groups

Enumerating security providers
Enumerating provider servers
Enumerating groups
Enumerating users in a group

Identifying Users

Getting the name of the current user
Determining if the current user belongs to a specified group

Customizing the Logging Class

Creating a custom logging class
An example
Using the example

Locking Down an Application

Locking Down a Server

Locking Down a Cluster

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