Summary

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In this chapter, we discussed numerous aspects of resource handling and configuration for servlet applications, in relation to real-life application scenarios. We looked at:

• Servlet initialization parameters and how they can be used to locate XML documents and directory entities

• The use of XML files for servlet configuration

• The use of XML and initialization parameters to implement a servlet that configures and registers a database connection factory at application startup

• How to implement a generic servlet authentication framework that can be dynamically configured to work with different types of data stores, including LDAP and JDBC

• How to persist servlet and session state, using relational databases and serialized Java objects

In the next chapter we will look at a new feature of the Servlet specification that allow us to add to the request and response processing within a web application - filters.

A

attributeAdded() method

• persisting session state example, 44

authenticate() method

• Authenticator interface, 21

• JDBC, 26

Authentication application

• configuring framework, 22

• custom exceptions, 21

• deploying, 24

• illustrates Data Access Object pattern, 19

AuthenticationConfig class

• Authentication application, 22

AuthenticationServlet implementing

• Authentication application, 23

Authenticator interface

• Authentication application, 21

B

binding

• DataSource objects, 11

C

classes

• DataSourceConfig class, 13

• LdapAuthenticator class, 33

• LdapConfig class, 31

Config class

• implementing, 6

configuring framework

• Authentication application, 22

Context> element

• Tomcat, server.xml deployment descriptor, 10

contextInitialized() method

• ServletContextListener interface, 17

context-param> element

• setting context-wide parameters, 4

context-wide parameters

• servlet initialization, 4

custom exceptions

• Authentication application, 21

D

Data Access Object pattern, 19

• Authentication application illustrates, 19

• web site, 19

data binding

• DataSource objects, 11

data servlet framework example

• deploying, 39

• persisting servlet state, 36

• testing, 39

data source binding, 11

• built-in, 12

• built-in, using, 12

• custom, 12

• custom, using, 13

database connectivity

• standard method, 11

DatabaseAuthenticator

• using, 28

DatabaseAuthenticator class

• JDBC implementing, 26

DatabaseName> element

• DataSourceConfig class, 14

DatabasePassword> element

• DataSourceConfig class, 14

databases

• JDBC, accessing with, 2

• servlets working with persistent data, 2

DatabaseUser> element

• DataSourceConfig class, 14

DataSource objects

• binding, 11

DataSource> element

• DataSourceConfig class, 14

DataSourceConfig class

• custom data source binding, 13

• generic solution, 17

• implementing, 13

• Oracle implementation using, 15

• SQL implementation using, 16

• standard elements, 13

DataSourceListener

• deploying the application, 18

DataSourceListener class

• binding Datasource object, 17

DataSourceListener context listener

• custom data source binding, 13

DefaultContext> element

• Tomcat, server.xml deployment descriptor, 10

destroy() method

• data servlet framework example, 39

• servlet persistence, 35

directory services, 2

• difference to SQL, 2

• LDAP (Lightweight Directory Access Protocol), 3

E

elements

• Context> element, 10

• context-param> element, 4

• DatabaseName> element, 14

• DatabasePassword> element, 14

• DatabaseUser> element, 14

• DataSource> element, 14

• DefaultContext> element, 10

• env-entry> element, 9

• init-param> element, 5

• param-value> element, 39

• resource-env-ref> element, 9

• ResourceParams> element, 10

• resource-ref> element, 9, 10, 12

• res-ref-name> element, 11

• ServerName> element, 14

• ServerPort> element, 14

• session-timeout> element, 47

env-entry> element

• JNDI initial context elements, 9

externalization

• persisting servlet state, 36

F

forName() method, Class

• database connectivity, 11

G

getElementText() method

• implementing Config class, 7

getInitParameter() method, ServletContext

• context-wide parameters, 4

• servlet-specific parameters, 5

getInitParameterNames() method, ServletContext

• context-wide parameters, 4

• servlet-specific parameters, 5

getResourceAsStream() method

• implementing Config class, 7

Group class

• Authentication application, 20

H

HttpSession object

• persisting session state, 40

HttpSessionAttributeListener

• persisting session state example, 43

HttpSessionListener

• persisting session state example, 43

HttpSessionListener interface

• persisting session state, 40

I

init() method

• DataSourceConfig class, 15

• implementing Config class, 7

initialization parameters

• servlet initialization, 4

init-param> element

• setting servlet-specific parameters, 5

J

J2EE specification

• standard resource factories, 10

JDBC (Java DataBase Connectivity)

• accessing relational databases, 2

• accessing resources, 25

• authenticate() method, 26

• creating database, 25

• DatabaseAuthenticator class, implementing, 26

• web site, 2

JNDI (Java Naming and Directory Interface)

• directory service, 3

• inherent JNDI support, 8

• initial context elements, 8

• resource binding, 8

JNDI namespace, 9

JSP (JavaServer Pages)

• DatabaseAuthenticator, 28

L

LDAP (Lightweight Directory Access Protocol)

• accessing resources, 31

• directory service, 3

• service provider extension, web site, 31

LdapAuthenticator class

• implementing, 33

LdapConfig class

• implementing, 31

M

methods

• attributeAdded() method, 44

• getElementText() method, 7

• getInitParameter() method, ServletContext, 4, 5

• getInitParameterNames() method, ServletContext, 4, 5

• getResourceAsStream() method, 7

• init() method, 7, 15

MySQL

• download web site, 2

MySQL JDBC driver

• download web site, 16

N

naming services, 2

O

Oracle implementation

• DataSourceConfig class, using, 15

Oracle JDBC drivers

• web site, 15

P

param-value> element

• data servlet framework example, 39

persistent resources

• accessing, 19

persisting session state example, 40

• creating database, 41

• deploying, 46

• implementing Request filter, 42

• implementing Requester class, 41

• implementing Session listener, 43

R

readResource() method

• data servlet framework example, 36, 37

readSerialize() method

• data servlet framework example, 36

readSerialized() method

• data servlet framework example, 38

references to web sites

• Data Access Object pattern, 19

• JDBC (Java DataBase Connectivity), 2

• LDAP service provider extension, web site, 31

• MySQL download, 2

• MySQL JDBC driver, 16

• Oracle JDBC drivers, 15

• resource configuration with Tomcat, 11

• Tyrex implementation, 12

relational databases see databases.

Request filter

• persisting session state example, 42

Requester class

• persisting session state example, 41

resource binding

• JNDI, 8

• standard, 10

resource-env-ref> element

• JNDI initial context elements, 9

ResourceParams> element

• Tomcat, server.xml deployment descriptor, 10

resource-ref> element

• built-in data source binding, 12

• configuring standard resource factory, 10

• JNDI initial context elements, 9

res-ref-name> element

• resource use, 11

S

Serializable interface, java.io

• persisting servlet state, 36

ServerName> element

• DataSourceConfig class, 14

ServerPort> element

• DataSourceConfig class, 14

servlet initialization parameters, 4

• context-wide, 4

• custom XML file or, 6

• purpose of, 6

• servlet-specific, 5

• using, 5

servlet persistence, 35

• data servlet framework example, 36

• persisting servlet state, 36

servlet XML configuration, 6

• implementing Config class, 6

ServletContextListener

• persisting session state example, 43

ServletContextListener interface

• contextInitialized() method, 17

• DataSourceListener class implements, 17

servlets

• persistent data, working with, 1

servlet-specific parameters

• servlet initialization, 5

Session listener

• persisting session state example, 43

session state

• persisting, 40

session-timeout> element

• persisting session state example, 47

SQL implementation

• DataSourceConfig class, using, 16

standard resource factories

• J2EE specification, 10

T

Tomcat

• resource configuration, web sites, 11

Tyrex implementation, web site, 12

U

User class

• Authentication application, 20

W

writeSerialized() method

• data servlet framework example, 37

X

XML (eXtensible Markup Language), 3

• custom XML file or servlet initialization parameters, 6

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