ePurchasing System ePurchasing System using using

Struts FrameworkStruts Framework

Java Administration Special Interest Group

December 9, 2002

Mimpin Halim

University of Hawai’i

Presentation Goals

Introduce UH ePurchasing System from 1,001 miles away Highlight ePurchasing requisition processing steps Benefits and Limitations of using Struts Introduce backend technologies from even further away

ePurchasing Goals

Mitigate risk by reducing human errors Shorter turn-around time Shift employees' focus from paperwork to productivity Use information more efficiently by integrating enhanced

transaction data with the existing systems Reduce cost of papers Transition to completely paperless purchasing system

University of Hawai’i ePurchasing System Overview

Supports requisition, purchase order, purchase order change, invoice and payment processing

Provides electronic approvals Supports multiple user roles with varied access to the

system features using LDAP authentication Validates accounts for activity and available budget

University of Hawai’i ePurchasing System Overview

(cont.)

Integrated with SuperQUOTE™ from CommercePoint Supports real-time encumbering of purchases and

real-time posting of payment expenditures Handles the creation, modification and storage/retrieval of

purchasing documents. Built using Struts Framework v1.0 in transition to v1.1

ePurchasing Implementation

System development started in August 2001 System was implemented in December 2001 Currently in phased development and release cycles

ePurchasing Statistics

As of November 5, 2002: 38 out of 58 units implemented 585 out of ± 800 users 3,891 processed purchase orders 3,767 payments $8,547,487.60 processed purchases

ePurchasingDocument flow of

Requisition

& Purchase Order

Requisition Document Flowfrom Business Logic Perspective

Purchase Order Document Flowfrom Business Logic Perspective

Account access validation Encumbrance posting

ePurchasing

Screen Captures

ePurchasing Login

ePurchasing Main Menu

ePurchasing Pending Requisitions

ePurchasing New Requisition Form

ePurchasing Requisition Submission

ePurchasing Requisition Transfer

ePurchasing Purchase Order Form

ePurchasing Hardcopy Purchase Order

Let’s talk about Struts!

Struts Overview

Open source framework for building web applications created by Craig MacClanahan.

Donated to Apache Software Foundation (ASF) in 2000 Provides extensible development environment Based on standard technologies like Java Servlets,

JavaBeans, ResourceBundles and XML Based on Model 2 architecture, a variation of MVC design

paradigm

Benefits of using Struts from Management perspective

Open Source Good documentation Stable and Mature Developed by industry experts Manageable learning curve Large user community

Benefits of using Struts from Developer perspective

Highly customizable

Feature-rich

Extendable and flexible

Widely supported with many free third party tools

Solid design with good documentation

Large user community with very active mailing list

Provides good separation between presentation and business logic.

Modular architecture promotes easier development

Limitations of using Struts from Developer perspective

Building large and complicated form

Lack of “dynamic properties”

Complicated client-side form/JavaScript interaction

Last two limitation have been addressed in Struts 1.1

Struts Framework Features

Supports internationalization - I18N

Database support and JDBC Connection pooling capabilities

Compatible with a variety of model implementations - EJB, JavaBeans, CORBA, etc.

Compatible with a varietiy of presentation layers - JSP, XML/XSLT, etc.

Write once, run anywhere philosophy

Struts Environment

Java Software Development Kit 1.2 or higher

Servlet 2.2/JSP 1.1 container or higher

XML parser compliant with JAXP 1.1 or higher

Inside Struts Framework

Controller

Model

View

Struts implementation of MVC in ePurchasing Architecture

Controller

ActionServlet

RequestProcessor

Action Classes

Controller : Components

Extends <javax.servlet.http.HttpServlets>

Receives all framework requests

Selects proper application module

Delegates request handling to the RequestProcessor instance

One instance per web application

Default implementation provided by framework

Controller : ActionServlets

One instance per web application module

Processes all request for module

Invokes proper Action instance

Default implementation provided by framework

Controller : RequestProcessor

Extends <org.apache.struts.action.Action>

In Struts 1.0 overrides the perform() method

In Struts 1.1 overrides the execute() method

Acts as a bridge between user-invoked URI and a business method

Provides information about which view should be rendered and returned

Controller : Action Classes

<!-- Initial requisition form with user defaults -->

<struts-config>

…

<action-mappings type="org.apache.struts.action.ActionMapping">

…

<!-- Initial requisition form with user defaults -->

<action path="/newReqInit"

type="edu.hawaii.purchasing.NewReqInitAction"

name="reqForm"

scope="request"

attribute="reqForm">

<forward name="success" path="/jsp/reqForm.jsp" />

</action>

…

</action-mappings>

</struts-config>

Example of ActionMapping

Requisition Document Flowfrom Business Logic Perspective

The Journey of Requisitionwith Action URI

Example of Action Class

public class NewReqAction

extends Action {

public ActionForward perform(ActionMapping mapping, ActionForm form,

HttpServletRequest request,

HttpServletResponse response)

throws IOException, ServletException {

// Check if user logged in

// (can be implemented by extending RequestProcessor)

HttpSession session = request.getSession(false);

LoginModel loginModel = new LoginModel();

if (!loginModel.isLoggedIn(session)) {

ActionForward login = mapping.findForward("login");

login.setRedirect(true);

return login;

}…

Example of Action Class (cont.)

…

// Get User’s information

String userID = (String) session.getAttribute("userID");

UserBean userBean = UserModel.getUserInfo(userID);

userBean.setFirstName((String) session.getAttribute("firstName"));

userBean.setLastName((String) session.getAttribute("lastName"));

userBean.setMiddleInitial((String) session.getAttribute("middleInitial"));

ReqModel reqModel = new ReqModel();

ReqBean reqBean = new ReqBean();

VndrBean vndrBean = new VndrBean();

reqBean = (ReqBean) reqModel.init(userBean, vndrBean, reqBean);

request.setAttribute("reqBean", reqBean);

return (mapping.findForward("success"));

} // perform()

} // eof: NewReqAction

Model

No model components provided

Struts supports any model component - EJB, Corba, JavaBeans, etc

Decouple model implementation from the framework

Model : Facts

Java Data Base Connectivity (JDBC 2.0) with Oracle Database utilizing Poolman Connection Pooling.

EntireX Java ACI v5.2.1.0 by Software AG to tap into the IBM Mainframe for Remote Procedure Call.

Model Component of ePurchasing

Example of Model Class

public class UserModel {

private static Category logger =

Category.getInstance(UserModel.class.getName());

public static UserBean getUserInfo(String userID)

throws IOException {

Connection conn = null;

Statement stmt = null;

ResultSet rs = null;

try {

conn =

DriverManager.getConnection(

PropertiesLoader.getProperty("oracle.datasource"));

stmt = conn.createStatement();

Example of Model Class (cont.)

// SQL Statement

String colNames =

"dept, deliv_addr_1, deliv_addr_2, deliv_addr_3, " +

“deliv_addr_4, deliv_city, deliv_st, deliv_zip, …”;

String tableName = "fmis_user ";

String sqlStmt = "select " + colNames + "from " + tableName +

"where user_id = '" + userID + "'";

rs = stmt.executeQuery(sqlStmt);

UserBean user = new UserBean();

while (rs.next()) {

user.setDelivDept(rs.getString("dept"));

user.setDelivAddr1(rs.getString("deliv_addr_1"));

user.setDelivAddr2(rs.getString("deliv_addr_2"));

…

}

return user;

} … //catch exception and finally close ResultSet, Statement, Connection

Invoker Action Class

…

// Get User’s information

String userID = (String) session.getAttribute("userID");

UserBean userBean = UserModel.getUserInfo(userID);

userBean.setFirstName((String) session.getAttribute("firstName"));

userBean.setLastName((String) session.getAttribute("lastName"));

userBean.setMiddleInitial((String) session.getAttribute("middleInitial"));

ReqModel reqModel = new ReqModel();

ReqBean reqBean = new ReqBean();

VndrBean vndrBean = new VndrBean();

reqBean = (ReqBean) reqModel.init(userBean, vndrBean, reqBean);

request.setAttribute("reqBean", reqBean);

return (mapping.findForward("success"));

} // perform()

} // eof: NewReqAction

<!-- Initial requisition form with user defaults -->

<struts-config>

…

<action-mappings type="org.apache.struts.action.ActionMapping">

…

<!-- Initial requisition form with user defaults -->

<action path="/newReqInit"

type="edu.hawaii.purchasing.NewReqInitAction"

name="reqForm"

scope="request"

attribute="reqForm">

<forward name="success" path="/jsp/reqForm.jsp" />

</action>

…

</action-mappings>

</struts-config>

Struts ActionMapping

Execute Remote Procedure Call to specific Broker program running in the Mainframe

Call is sent to the Broker as a String containing program name, parameters needed for the program to execute

Return user-defined number of bytes in the form of byte arrays

Can do more than one invocation with a given open connection to the host running the EntireX Broker server

Model : Natural Broker

Using Natural Broker

public String[][] getBalance(String document)

throws IOException

{

…

String brokerParms = "JWSPEBAL28000" + document + fisYear;

int receiveBufferSize = 28000;

byte[] replyArray = null;

String[][] acctBalances = new String[1][5];

BrokerMessage bReply = nb.perform(brokerParms, receiveBufferSize);

if (bReply == null) {

if (logger.isDebugEnabled()) {

logger.debug("getBalance() - No results");

}

return acctBalances;

} else {

…

Using Natural Broker (cont.)

replyArray = nb.getResults(bReply);

String count = new String(replyArray, 0, 2);

int acctCount = Integer.parseInt(count);

if (acctCount == 0) {

return acctBalances;

}

acctBalances = new String[acctCount][5]; // each account has 5 properties

for (int i = 0; i < acctCount; i++) {

int rOffset = 2 + (i * 40);

acctBalances[i][0] = new String(replyArray, rOffset, 2); // campus

acctBalances[i][1] = new String(replyArray, rOffset + 2, 6); // account

acctBalances[i][2] = new String(replyArray, rOffset + 8, 4); // subcode

acctBalances[i][3] = new String(replyArray, rOffset + 12, 14); // curr. amt

acctBalances[i][4] = new String(replyArray, rOffset + 26, 14); // liq. amt …

View

Java Server Pages

HTMLs

JavaScripts and StyleSheets

Resources Bundles

JavaBeans extending ActionForms

Custom Tags - HTML, Bean, Logic

View : Components

Upgrade to Struts 1.1

Utilize Validators and Tiles from Struts 1.1

Use XML/XSLT for View Component

What’s new in 1.1?

http://jakarta.apache.org/struts/userGuide/release-notes-1.1-b2.html

Future Improvements

Questions?