This document discusses developing e-commerce applications using Oracle and Java. It covers challenges of e-commerce such as high availability, performance, and security. It then discusses important Java features, when to use Java, and PL/SQL packages and their Java equivalents. The document also discusses Java server platforms, ensuring JVM setup, configuration tips, checking IIOP connectivity, supporting application developers, and choosing appropriate client-side interfaces like JDBC and SQLJ. It provides tips on choosing the right tools, reducing footprint, improving speed, increasing concurrent connections, using PL/SQL in Java, and Java security.

1. Developing e-Commerce Applications Using
Oracle and Java
Megh Thakkar
Director of Database Technologies
Quest Software

2. Industry Directions
Web Based
Companies
E-Commerce
Brick and Mortar

3. e-Commerce Challenges
High Availability (24*7*365/366)
Performance
Scalability
Security / Hackers

4. Reality Check
Company Outage Cost Results
June 12, 1999 26% stock price
eBay $3-5 Million
22 hours drop
AT&T April 13, 1998 $40 Million Changed
26 hours in rebates infrastructure
Upgrade
April 6, 1996 $3 Million
AOL infrastructure
24 hours in rebates $80 Million
Feb 24-Apr 21, 99 Upgrade
Charles Schwab undetermined infrastructure
4 hours $70 Million
Loss of integrity
Bank of Singapore July 1-8, 1999 undetermined
and interest
$10 Million Key betting days
Tabcorp Australia October 1999
in rebates lost
22% stock price
E*Trade March 3-4, 1999 undetermined
drop

5. Important Java Features
 Object-oriented language
 It allows the development of applications using an
open standard
 It enables the development of portable applications
 It allows the reuse of code by means of JavaBeans
and Enterprise JavaBeans (EJB) resulting in
improved productivity
 It can execute in browsers, application servers, and
databases
 It allows applications to be deployed in two-tier and
multi-tier configurations

6. When to use Java?
 CPU-intensive “number crunching”
operations
 To overcome PL/SQL limitations
- Host command
- Limitations with UTL_SMTP
 Extend the client types
 When object-oriented features are more
suitable
REMEMBER THAT JAVA IS CASE-SENSITIVE

7. PL/SQL Packages and Their
Java Equivalents
Standard PL/SQL Equivalent Java implementation
package
DBMS_ALERT No pure Java equivalent.
DBMS_DDL JDBC has an equivalent mechanism for this.
DBMS_JOB No pure Java equivalent.
DBMS_LOCK No pure Java equivalent.
DBMS_MAIL JavaMail
DBMS_OUTPUT DBMS_JAVA.SET_STREAMS can be used to
redirect System.out to DBMS_OUTPUT. The
standard Java OutputStream api can be used
with the subclass
oracle.aurora.rdbms.OracleDBMSOutputStream
DBMS_SESSION JDBC can be used to execute ALTER SESSION
DBMS_SQL JDBC can be used.
DBMS_UTILITY No pure Java equivalent
UTL_FILE Classes File, FileOutputStream and
FileInputStream. Use of these classes
requires the granting of JAVAUSERPRIV
privilege.

8. Java Server Platforms
Two related Java execution
environments are provided in Oracle9i:
 Oracle JServer VM that is integrated
with Oracle9i allowing data intensive
Java logic to run and
 Java VM integrated with Oracle
Application Server (iAS) as a Java
cartridge

9. Ensuring JVM Setup
Select count(*) from
dba_objects where object_type
like ‘JAVA%’;
Select
dbms_java.longname(name)
from sys.obj$ where
type# = 29 and status != 1;

10. Configuration Tips
 Use MTS
 Configure Large pool

11. Checking IIOP Connectivity
 Lsnrctl services
 netstat
 sess_sh

12. Support for Different Types of
Application Developers
 Database programmers can write traditional stored
procedures, triggers and object-relational methods
in Java
 Component-based Java developers can write
reusable server code in the form of Enterprise
Java Beans
 Distributed system developers can develop
CORBA servers in Java
 Web developers can use Java Server Pages to
embed Java tags in HTML pages to dynamically
generate HTML pages directly from Oracle9i

13. Client-side Programmatic
Interface
Oracle9i provides two different
client-side programmatic interfaces
for Java developers:
 JDBC (Four types)
 SQLJ (allowing SQL to be
embedded in Java)

14. Choosing the Appropriate JDBC
Driver
Fr
ee
at
u JOr
DCi
B Iv
C dr
e Jt d r
Dh r
Bi i
Cnve
S rr l N
u t a to
p fps
p op
o e Y
e
s
S rr * A Qt
u t S el L
p f Q tl *
p oL
o N SeN OT P
nC i
lP s
y/I
aer
dre
as
p a
t sr
ut
pe
pd
o
s r id
u t ni
p ec n
p dl g
o u
IN P
Pa i
Cm p
,e e
d s
aC
nP
d/
TPI
Ep
nt
ci
ro
yn Y B ih Nu t
e y ne op e
s u t
. sg tp d
sr
o
A c ek
det
v dw
a Nr
n o
OnN
p ot
t f8
i
o e
D re
r t
i y
v p
e T 2 vJ T4 v
y d r By d r
p r . Cp r .
e i D
e e ie
if a
na r
tc e
ee
rs M ufa
a s J
k e a
e ov
s
i m dt st c c
me t
pn h
lt a
ee os o t
c tn
k on
e e
u C i ad t o
s I n ci l a
e t t tr y n
O oer e t
c
wtr
iha
t ec
h Oe Oe a
l r da
a as
c te
l b
da
as
te
a
b

15. Choosing the Right Tool
Characteristics Enterprise Jdeveloper WebDB (portals)
developer suite: Suite (+ UML):
Designer, Java IDE, BC4J,
Developer, UML Modeling
Developer Server
Interactive Best Good Good
user interface
Single point of Good Better Best
access to
corporate
services
E-Commerce Intranet-based Internet- Internet-
support based based
Programming PL/SQL-based; Java-based; Java-based;
model declarative component component
model model model
Mature & proven Yes Partial No
technology
Web enabling Best Good Good
legacy systems

16. Challenges in Developing a
Scalable Java Environment
 Interaction of threads and automated
storage management or garbage collection
 Achieving minimum incremental per-user
session footprint
 Java executes platform-independent
byte codes on top of a virtual machine. The
virtual machine then deals with the specific
hardware platform. This makes the
execution slightly inefficient

17. Garbage Collection Issues
Garbage collection is a major aspect of the Java language’s
automated storage management mechanism
 Although Oracle9i supports Java language level threads, all
Java code in Oracle9i executes as a call within a session
 Java programs can use the same scalability architecture used
by Oracle internally
 The garbage collector used in Oracle9i Java virtual
machine never collects garbage from more than one user at
any time
 Each user experiences as if she is executing her own Java
code in her own virtual machine

18. Factors Affecting Footprint
 Size of the program
This is determined by the number of classes and
methods and the amount of code they contain.
 Program complexity
Amount of core class libraries used as the
program executes
 State objects used
This depends upon the number of objects
allocated, their size and how many are retained
across calls
 Ability of the garbage collector and memory
manager to cope with the demands of the program

19. Reducing Footprint
 Footprint can be reduced by sharing resources across
Java processes
 Release large data structures at end-of-call
 Data structures that are candidates for end-of-call
optimization include:
- Buffers or caches
- Static fields
- Dynamically built data structures

20. Initialization Parameters
 The following parameters affect memory usage
and performance of Java code:
- shared_pool_size
- java_pool_size
- java_soft_sessionspace_limit (default 1MB)
- java_max_sessionspace_size (ORA-29554) (default 4GB)
SELECT * FROM v$sgastat WHERE
pool = ‘java pool’;

21. Improving Speed of Execution
 Use natively compiled code such as core Java
class libraries and Oracle-provided Java code

22. Oracle9i Solutions for Increasing
the Concurrent Connections
 Multi-Threaded Server
 Connection manager
 Connection pooling
 Orastack (Windows NT only)

23. Multi-threaded Server
 Allows many user threads to share very few
server threads
 User threads connect to a dispatcher
process which routes client requests to the
next available server thread
Result: More users are supported

24. Connection Manager
 Concentrates multiple clients into a single
multiplexed data connection
 Clients can use different protocols
Result: Applications can be used continuously by
the clients

25. Connection Pooling
 Places idle users in a suspended mode and
reassigns their physical connections until they
become active again
Result: Ideal for users that need to be logged on all
the time but don’t need to really use the application

26. Orastack
 Can be used to change the default reserved
stack space used by each Oracle thread
USE WITH EXTREME CAUTION
Result: Allows more user connections

27. Using PL/SQL in JAVA – PL2Java
 Part of the iAS product
 Must first install DBMS_PACKAGE in the SYS schema
 Generates JAVA wrapper classes for PL/SQL procedures and
functions in PL/SQL packages
 The wrapper classes can be called from the JAVA programs to
invoke the PL/SQL program units
Syntax:
pl2java username/password@connect-string plsql_package

28. Java Server Pages
 HTML pages with JAVA as the embedded language
 Different from mod_plsql (or PL/SQL cartridge)
 JSPs cache compiled code
 Creation, compilation and execution of servlets is
handled by the JSP engine

29. Java Security
 Oracle 8.1.5 allows security through roles
 Oracle 8.1.6 and above allows roles as well as Java 2 security
 initjvm.sql creates 2 roles:
JAVAUSERPRIVS (open a TCP/IP socket; read/write file using
UTL_FILE_DIR)
JAVASYSPRIVS (all privs from JAVAUSERPRIVS + create
subprocess, set socket factory, set stream handler, listen on
specific ports)
 Use DBMS_JAVA package
 Views: DBA_JAVA_POLICY and USER_JAVA_POLICY

30. THANK YOU
BUY QUEST
FOR LISTENING
PRODUCTS