Overview of Application and Applet Functionality

This section compares and contrasts the basic functionality of JDBC applications and applets, and introduces Oracle extensions that can be used by application and applet programmers.

Application Basics

You can use either the Oracle JDBC Thin driver or the JDBC OCI driver for a client application. Because the JDBC OCI driver uses native methods, there can be significant performance advantages in using this driver for your applications.

An application that can run on a client can also run in the Oracle server, using the JDBC server-side internal driver.

If you are using a JDBC OCI driver in an application, then the application will require an Oracle installation on its clients. For example, the application will require the installation of Net8 and client libraries.

Both the OCI drivers and the Thin driver offer support for data encryption and integrity checksum features of the Oracle Advanced Security option (formerly known as ANO or ASO). See "JDBC Client-Side Security Features". Such security is not necessary for the server-side internal driver.

Applet Basics

This section describes the issues you should take into consideration if you are writing an applet that uses the JDBC Thin driver.

For more about applets and a discussion of relevant firewall, browser, and security issues, see "JDBC in Applets".

Applets and Security

Without special preparations, an applet can open network connections only to the host machine from which it was downloaded. Therefore, an applet can connect to databases only on the originating machine. If you want to connect to a database running on a different machine, you have two options:

• Use Oracle8 Connection Manager on the host machine. The applet can connect to Oracle8 Connection Manager, which in turn connects to a database on another machine.

• Use signed applets, which can request socket connection privileges to other machines.

Both of these topics are described in greater detail in "Connecting to the Database through the Applet".

The Thin driver offers support for data encryption and integrity checksum features of the Oracle Advanced Security option. See "JDBC Client-Side Security Features".

Applets and Firewalls

An applet that uses the JDBC Thin driver can connect to a database through a firewall. See "Using Applets with Firewalls" for more information on configuring the firewall and on writing connect strings for the applet.

Packaging and Deploying Applets

To package and deploy an applet, you must place the JDBC Thin driver classes and the applet classes in the same zip file. This is described in detail in "Packaging Applets".

Oracle Extensions

A number of Oracle extensions are available to Oracle JDBC application and applet programmers, in the following categories:

• type extensions (such as ROWIDs and REF CURSOR types)

• wrapper classes for SQL types (the oracle.sql package)

• support for custom Java classes to map to user-defined types

• extended LOB support

• extended connection, statement, and result set functionality

• performance enhancements

See Chapter 6, "Overview of Oracle Extensions" for an overview of type extensions and extended functionality, and succeeding chapters for further detail. See Chapter 13, "Performance Extensions" regarding Oracle performance enhancements.

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