> # About the JDBC Client

> The JDBC Client provides JDBC access through any Java-enabled applet, application, or application server. It delivers high-performance point-to-point and n-tier access to industry-leading data stores across the Internet and intranets. The JDBC Client is optimized for the Java environment, allowing you to incorporate Java technology and extend the functionality and performance of your existing system. The following components are shipped with the JDBC Client:

> - SequeLink for JDBC Driver
> - SequeLink Proxy Server
> - DataDirect Spy™ for JDBC
> - DataDirect Test™ for JDBC
> - DataDirect Connection Pool Manager
> - J2EE Connector Architecture resource adapters

> The JDBC Client runs on 32-bit and 64-bit platforms. No changes are required to existing applications to enable them to run on 64-bit platforms.

> ### JDBC Driver

> The JDBC driver is compliant with the JDBC 3.0 specification, including the following features:

> - Java Naming Directory Interface (JNDI) for naming databases
> - Connection pooling
> - Distributed transactions

> ### SequeLink® Proxy Server

> Installing the SequeLink Proxy Server on the Web server from which your JDBC applets are downloaded allows untrusted applets to connect to SequeLink Servers on hosts other than the Web server, as shown in Figure 5-1.

> Figure 5-1. SequeLink Proxy Server Installed on a Web Server

> In addition, you can use SSL encryption with the proxy server to encrypt data between the SequeLink Proxy Server and the JDBC Client. You can also use SSL with a Java application running on your Intranet to secure data over your entire network by installing the SequeLink Proxy Server on the same machine as the SequeLink Server. For example, you may want to use SSL to encrypt the data sent between an application server and the data store serviced by a SequeLink Server on another machine.

> ### DataDirect Spy™

> DataDirect Spy is a software component for tracking JDBC calls at runtime. It passes calls issued by an application to an underlying JDBC driver and logs detailed information about those calls. DataDirect Spy provides the following advantages:

> - Logging is JDBC 3.0-compliant, including support for the JDBC 2.0 Optional Package.
> - Logging is consistent, regardless of the JDBC driver used.
> - All parameters and function results for JDBC calls can be logged.
> - Logging can be enabled without changing the application.
> - DataDirect Spy can only be used with the SequeLink for JDBC Driver and the DataDirect Connect® for JDBC drivers.

> When you enable DataDirect Spy for a connection, you can customize DataDirect Spy logging for your needs by setting one or multiple options for DataDirect Spy. For example, you may want to direct logging to a local file on your machine.

> ### DataDirect Test™

> DataDirect Test is a menu-driven software component that is included in the SequeLink package. It helps you debug your JDBC applications and learn how to use the JDBC driver. DataDirect Test contains menu selections that:

> - Correspond to specific JDBC functions-for example, connecting to a database or passing a SQL statement.
> - Encapsulate multiple JDBC function calls as a shortcut to perform some common tasks, such as displaying the contents of a result set.

> DataDirect Test displays the results of all JDBC function calls in one window, while displaying fully commented, Java JDBC code in an alternate window.

> ### DataDirect Connection Pool Manager

> Database access performance can be improved significantly when connection pooling is used. Connection pooling means that connections are reused rather than created each time a connection is requested.

> Your application can use connection pooling through the DataDirect Connection Pool Manager. See "JDBC Connection Pool Manager" for more information about the DataDirect Connection Pool Manager.

> ### J2EE Connector Architecture (JCA) Resource Adapter

> The J2EE Connector architecture (JCA) defines a standard structure for connecting the J2EE platform to Enterprise Information Systems (EISs). JCA enables the integration of EISs with application servers and enterprise applications.

> The JDBC Driver supports appropriate JDBC functionality through the JCA SPI by providing a resource adapter. The DataDirect resource adapter is provided in a resource archive (RAR) file, and is named like the JDBC driver files, for example, sljc.rar. See the Installed File list in the SequeLink readme file for the names and locations of the RAR files. See the SequeLink Installation Guide for information about creating the resource adapters. See "J2EE Connector Architecture Resource Adapter" for more information about using resource adapters with SequeLink.

> ### JDBC Client Directory Structure

> Table 5-1 shows the JDBC Client directory after installation and provides a description of the files.

> Table 5-1. JDBC Client Directory and Files
> Directories and Files | Description
> --- | ---
> books/*.* | Files for the SequeLink online books, which are in HTML format.
> driver/examples/CheckAgainstCertificateFromFile.java driver/examples/CheckAgainstCertificateFromJar.java driver/examples/KeyStoreCertificateChecker.java | Contain Java source files that provide examples of certificate checkers.
> driver/examples/JNDI_FILESYSTEM_Example.java driver/examples/JNDI_LDAP_Example.java | Contain Java source files that allow you to create JDBC data sources. These source files must be adapted for your environment, and subsequently compiled and run.
> driver/lib/sljc.jar | JAR file containing all classes of the JDBC driver implementing the JDBC 3.0 API. To load the driver, add this path to your CLASSPATH variable. This JAR file also contains all classes of the JDBC driver implementing the JDBC 2.0 Optional Package. To use the JDBC 2.0 Optional Package, add this path to your CLASSPATH variable.
> driver/lib/slssl14.jar driver/lib/iaik_jce_full.jar | JAR files required for J2SE 1.4.2 or higher JVMs. The files contain all classes of the JDBC driver that implement SSL encryption.
> driver/lib/sljc.rar | Resource Archive for use with J2EE Connector Architecture.
> help/*.* | Files for the HTML-based online help for the JDBC driver.
> testforjdbc/lib/testforjdbc.jar | JAR file containing all the DataDirect Test classes. To use DataDirect Test, add this path to your CLASSPATH variable.
> testforjdbc/testforjdbc14.bat | Batch file that starts DataDirect Test.
> testforjdbc/testforjdbc14.sh | UNIX shell script that starts DataDirect Test.
> pool/lib/pool.jar | JAR file containing all the classes for the DataDirect Connection Pool Manager.
> proxy/cmdsrvc.exe | Executable that registers the SequeLink Proxy Server as a Windows service.
> proxy/proxyserver14.bat | Batch file that starts the SequeLink Proxy Server.
> proxy/cert/ | Directory containing demo certificates.
> proxy/demos/com/ddtek/sequelink/demo/ demo.properties proxy/demos/com/ddtek/sequelink/demo/ GenerateDemoCertificates$DN.class proxy/demos/com/ddtek/sequelink/demo/ GenerateDemoCertificates.class | Contain Java files you can use to generate certificates.
> proxy/demos/com/ddtek/sequelink/demo/ KeyTool.class | Contains a Java class file that extracts certificates from a Java2 KeyStore and converts certificates to different formats.
> proxy/lib/slproxy.jar | JAR file containing all classes for the SequeLink Proxy Server.
> proxy/log | The directory that contains all messages logged by the SequeLink Proxy Server.
> proxy/proxyserver14.sh | UNIX shell script that starts the SequeLink Proxy Server.
> spy/lib/spy.jar | JAR file containing all Spy classes. To use DataDirect Spy, add this path to your CLASSPATH variable.
> sun/lib/jdbc2_0-stdext.jar | JAR file containing redistributable Sun Microsystems components for the JDBC 2.0 Optional Package.
> sun/lib/jndi.jar | JAR file containing redistributable Sun Microsystems components for JNDI 1.2.
> sun/lib/jta-spec1_0_1.jar | JAR file containing redistributable Sun Microsystems components for JTA 1.0.1.
> sun/lib/fs/fscontext.jar sun/lib/fs/providerutil.jar | JAR files containing redistributable Sun Microsystems components for the File System JNDI Provider.
> sun/lib/ldap/jaas.jar sun/lib/ldap/ldap.jar sun/lib/ldap/ldapbp.jar sun/lib/ldap/providerutil.jar | JAR files containing redistributable Sun Microsystems components for the LDAP JNDI Provider.