IMS Connectivity in an On Demand Environment: A Practical Guide to IMS Connectivity

502 IMS Connectivity in an On Demand Environment: A Practical Guide to IMS Connectivity

System.out.println("IMS RDS Servlet : Caught exception in final section is: " + t);

arg0.setAttribute("t",t.getMessage());

RequestDispatcher disp = arg0.getRequestDispatcher("Output.jsp");

System.out.println("IMS RDS Servlet : Success Dispatch Result");

System.out.println("IMS RDS Servlet : End" );

disp.forward(arg0,arg1);

}

}

}

}

ImsJavaRdsSample.java

ImsJavaRdsSample.java is the servlet for the IMS JDBC access with the local transaction

semantics, as shown in Example B-2.

Example: B-2 ImsJavaRdsSample.java

package imsRds;

import java.io.IOException;

import javax.naming.Context;

import javax.naming.InitialContext;

import javax.servlet.RequestDispatcher;

import javax.servlet.Servlet;

import javax.servlet.ServletException;

import javax.servlet.http.HttpServlet;

import javax.servlet.http.HttpServletRequest;

import javax.servlet.http.HttpServletResponse;

import java.sql.*;

import javax.sql.*;

public class ImsRdsSample extends HttpServlet implements Servlet {

DataSource dataSource;

public void init() throws ServletException {

try {

//Obtain the initial JNDI Naming context for JDBC Connection

System.out.println("IMS RDS Servlet : Start ");

Context initialContext = new InitialContext();

dataSource = (DataSource)initialContext.lookup("java:comp/env/imsjavaRDSRedBook");

System.out.println("IMS RDS Servlet : Success Create DataSource");

}catch (Exception e){

e.printStackTrace();

}

}

protected void doPost(HttpServletRequest arg0, HttpServletResponse arg1)

throws ServletException, IOException {

Connection connection = null;

Statement statement = null;

ResultSet results = null;

String LastName = null;

Appendix B. IMS RDS application example 503

String FirstName = null;

String Extension = null;

String ZipCode = null;

try{

//Get JDBC Conneciton

connection = dataSource.getConnection();

System.out.println("IMS RDS Servlet : Success Get Connection");

//Get Key Value from Input Page

String keyValue = arg0.getParameter("keyValue").trim();

//Issue SQL

String queryString = "SELECT * FROM PhoneBook.Person "

+ "WHERE Person.LastName = '" + keyValue + "'";

statement = connection.createStatement();

results = statement.executeQuery(queryString);

//Get Output

while(results.next()) {

LastName = results.getString("Person.LastName");

FirstName = results.getString("Person.FirstName");

Extension = results.getString("Person.Extension");

ZipCode = results.getString("Person.ZipCode");

}

System.out.println("IMS RDS Servlet : Success Get Result");

//Commit LocalTransaction

connection.commit();

System.out.println("IMS RDS Servlet : Success Commit LocalTransaction");

//Set the result to the JSP

arg0.setAttribute("OUT__LastName", LastName);

arg0.setAttribute("OUT__FirstName", FirstName);

arg0.setAttribute("OUT__Extension", Extension);

arg0.setAttribute("OUT__ZipCode", ZipCode);

} catch (Exception e) {

try{

//RollBack LocalTransaciton

connection.rollback();

System.out.println("IMS RDS Servlet : Success Rollback LocalTransaction");

//Close JDBC Resources

if (statement != null) {statement.close();}

if (connection != null) {connection.close();}

System.out.println("IMS RDS Servlet : Caught exception in main section is: " + e);

arg0.setAttribute("e",e.getMessage());

} catch (Exception s){

System.out.println("IMS RDS Servlet : Caught exception in rollback section is: " + s);

arg0.setAttribute("s",s.getMessage());

}

} finally {

try{

//Close JDBC Resources

if (statement != null) {statement.close();}

if (connection != null) {connection.close();}

RequestDispatcher disp = arg0.getRequestDispatcher("Output.jsp");

disp.forward(arg0,arg1);

System.out.println("IMS RDS Servlet : Success Dispatch Result");