Starting with DAS

This page provides links to DAS samples and explains a simple "how to" and gives step-by-step instructions to check one of the DAS features - ColumnConverter. Other DAS features can be tried on similar lines.

Many sample examples demonstrating different DAS features are available on https://svn.apache.org/repos/asf/incubator/tuscany/java/das/samples e.g.

companyweb - tomcat based web sample
customer - J2SE based standalone application

Check readme files e.g. For companyweb https://svn.apache.org/repos/asf/incubator/tuscany/java/das/samples/companyweb/readme.htm
for basic steps on how to get the sample running.

Once the sample is running, parts of sample can be modified based on the requirement or new code can be added from-scratch. Many features supported by DAS are listed in User Guide - http://cwiki.apache.org/confluence/display/TUSCANY/RDB+DAS+-+User+Guide.

This document details the changes needed to different part of the web sample (companyweb) to experiment with more features of DAS than just basic CRUD.Let us take example of checking how to use ColumnConverters. For details on feature testing, check Tests under https://svn.apache.org/repos/asf/incubator/tuscany/java/das/rdb/src/test/

1> As a first step you need to implement Converter interface in a class to achieve the required
column conversion. Check org.apache.tuscany.das.rdb.test.mappings.StringObfuscationConverter from the svn repository for example of converter. Make your converter class available in (Tomcat root)webapps/companyweb/WEB-INF/classes.

2> DAS functions based on external Configuration, e.g. CompanyConfig.xml file in companyweb sample. The purpose of this Config file to supply information for DataSource connection, Commands (SQL) (that DAS can execute against Database) and Database schema like - Table/Columns, Relationship and so forth. Please check Architecture Guide for complete details about Config.xsd ()
at http://cwiki.apache.org/confluence/display/TUSCANY/RDB+DAS+-+Architecture+Guide. Modify Config get converter working. The <ConnectionInfo> element should match the resource name from server.xml for DataSource.Add a <Table> which has a column with converter class name of the class you just created. Add a <Command> with kind="Select" for this table/column e.g.

No Format

<Command name="getFirstCustomer" SQL="Select * from CUSTOMER where ID = 1" kind="Select"/>

<Table tableName="CUSTOMER">
<Column columnName="ID" primaryKey="true"/>
<Column columnName="LASTNAME" converterClassName="org.apache.tuscany.das.rdb.test.mappings.StringObfuscationConverter"/>
</Table>

3> Now the code and config setup is complete. What remains is calling the new command from .jsp and
servlet. Follow the technique similar to CompanyClient.java and Company.jsp to call the new command. The returned results will verify that the converter is called and the column value from database is converted based on converter logic.
4> For more details check the test cases from ConverterTests in https://svn.apache.org/repos/asf/incubator/tuscany/java/das/rdb/src/test/.

Assumption: Tomcat version 5.5.* or 6.0.10 , Derby version 10.1.2.1.

Troubleshooting Checkpoints: Check the following and if still having issues , report at http://cwiki.apache.org/confluence/display/TUSCANY/Issue+Tracking

All libraries are present in (Tomcat root)/webapps/companyweb/WEB-INF/lib (these libs can
be taken from companyweb sample or can be downloaded from web)
i) common-(latest version).jar
ii) ecore-(latest version).jar
iii) ecore-change-(latest version).jar
iv) ecore-xmi-(latest version).jar
v) log4j-(latest version).jar
vi) sdo-api-xxx.jar
vii) tuscany-das-rdb-xxx.jar
viii) tuscany-sdo-xxx.jar
ix) xsd-(latest version).jar
x) derby driver jar - or whichever database you are planning to use
The Database exists with required tables and data.

WEB-INF/web.xml has entry under welcome-file-list for required .jsp like -

No Format
<web-app> <display-name>Tuscany DAS sample Company WEB</display-name> <welcome-file-list id="WelcomeFileList"> <welcome-file>Company.jsp</welcome-file> </welcome-file-list> </web-app>

META-INF/context.xml has entry for the datasource the sample is using like -

No Format

<?xml version="1.0" encoding="UTF-8"?>
<Context path="/DAS Stand alone app" debug="5" reloadable="true" crossContext="true">
   <Manager pathname=""/>
   <ResourceLink name="jdbc/dastest" global="jdbc/dastest" type="javax.sql.DataSource" />                     
</Context>

(Tomcat root)/conf server.xml has entry similar to below for the datasource -

No Format

<Resource name="jdbc/dastest"
      type="javax.sql.DataSource"  auth="Container"
      description="Derby database for DAS Company sample"
      maxActive="100" maxIdle="30" maxWait="10000"
      username="" password=""
      driverClassName="org.apache.derby.jdbc.EmbeddedDriver"
      url="jdbc:derby:c:\apache-tomcat-5.5.20\Databases/dastest;create=true"/>

_______________________________________________________________________________________________

old guide - just to compare, can be deleted later -
h1. Starting with DAS

This is a quick guide for building a simple aplication using DAS/SDO. You will learn the simple steps required to
build "CompanyWeb" sample web application. This sample users MySQL and Tomcat.

A. Initial Setup

Install Tomcat(latest version) and MySQL(latest version). Please indicate which version of the Tomcat and MySQL is this tested with?
Download dependencies and libraries Please add a link to this information. Which dependencies and libraries?
Create companyweb directory in (Tomcat root)/webapps/. EX: (Tomcat root)/webapps/companyweb
Create the directory (Tomcat root)/webapps/companyweb/WEB-INF/lib and copy the libraries into it. As an alternative, you can copy the libraries into (Tomcat root)/common/lib directory.
The required libraries are:
i) common-(latest version).jar
ii) ecore-(latest version).jar
iii) ecore-change-(latest version).jar
iv) ecore-xmi-(lateste version).jar
v) log4j-(latest version).jar
vi) sdo-api-xxx.jar
vii) tuscany-das-rdb-xxx.jar
viii) tuscany-sdo-xxx.jar
ix) xsd-(latest version).jar
x) mysql-connector-java-(latest version).jar -> This is the JDBC connector, It'll be used to connect to Mysql database

B. Creating CompanyWeb Database

After setting up your enviroment, the next step will be to create the databse where the DAS will interact with.

Run the following commands in the MySQL Command Shell
create database companyweb; -> This command will create the CompanyWeb database
use companyweb; -> Set the shell to work with companyweb database

Create a text file and name it as "comapnyweb.sql", you should insert the following lines in this file

No Format

CREATE TABLE EMPLOYEE ( 
ID INTEGER NOT NULL AUTO_INCREMENT, NAME VARCHAR(30), SN VARCHAR(10), MANAGER SMALLINT, DEPARTMENTID INTEGER, PRIMARY KEY (ID) 
); 

CREATE TABLE DEPARTMENT ( 
ID INTEGER NOT NULL AUTO_INCREMENT, NAME VARCHAR(30), LOCATION VARCHAR(30), NUMBER VARCHAR(10), COMPANYID INTEGER, EOTM INTEGER, PRIMARY KEY (ID) 
); 

CREATE TABLE COMPANY ( 
ID INTEGER NOT NULL AUTO_INCREMENT, NAME VARCHAR(30), PRIMARY KEY (ID) 
); 

CREATE UNIQUE INDEX SQL060217085530980 ON COMPANY (ID ASC); 

CREATE UNIQUE INDEX SQL060217085531710 ON DEPARTMENT (ID ASC); 

INSERT INTO COMPANY VALUES (51, "ACME Publishing"); 

INSERT INTO COMPANY VALUES (52, "Do-rite plumbing"); 

INSERT INTO COMPANY VALUES (53, "MegaCorp");

Run the following command in the Mysql Shell to execute the script that creates tables, constraints, etc.
Code Block
source (path)/companyweb.sql

C. Creating XML configuration file

Would be nice to explain what this file is used for

Create the file CompanyConfig.xml in the directory (Tomcat root)/webapps/companyweb/WEB-INF/classes

Edit it and write the following code

No Format

<?xml version="1.0" encoding="ASCII"?> 
<Config xmlns="http:///org.apache.tuscany.das.rdb/config.xsd"> 

<Command name="all companies" SQL="select * from COMPANY" kind="Select"/> 
<Command name="all companies and departments" SQL="select * from COMPANY left outer join DEPARTMENT on COMPANY.ID = DEPARTMENT.COMPANYID" kind="Select"/> 
<Command name="all departments for company" SQL="select * from COMPANY inner join DEPARTMENT on COMPANY.ID = DEPARTMENT.COMPANYID where COMPANY.ID = ?" kind="Select"/> 
<Command name="company by id with departments" SQL="select * from COMPANY left outer join DEPARTMENT on COMPANY.ID = DEPARTMENT.COMPANYID where COMPANY.ID = ?" kind="Select"/> 
<Table tableName="COMPANY"> 
<Column columnName="ID" primaryKey="true" generated="true"/> 
</Table> 
<Table tableName="DEPARTMENT"> 
?	<Column columnName="ID" primaryKey="true" generated="true"/> 
</Table> 
<Relationship name="departments" primaryKeyTable="COMPANY" foreignKeyTable="DEPARTMENT" many="true"> 
<KeyPair primaryKeyColumn="ID" foreignKeyColumn="COMPANYID"/> 
</Relationship> 
</Config>

Save the file.

D. Creating the class and jsp which manages the DAS/SDO features

What do you mean by a class manages DAS/SDO features? Do you mean, a class that manipulates or uses DAS/SDO features?

Create the file CompanyClient.java in the directory (Tomcat root)/webapps/companyweb/WEB-INF/classes/org/apache/tuscany/samples/das/companyweb
Write the following code in the file :
It would be helpful to explain what the purpose of this code is. I would suggest you move this code to another page since it is so long and instead have a link on this page

No Format

package org.apache.tuscany.samples.das.companyweb;

import java.io.InputStream;
import java.util.ArrayList;
import java.util.Iterator;
import java.util.List;
import java.util.Random;

import org.apache.tuscany.das.rdb.Command;
import org.apache.tuscany.das.rdb.DAS;

import commonj.sdo.DataObject;

public class CompanyClient {

    private Random generator = new Random();

    private DAS das = DAS.FACTORY.createDAS(getConfig("CompanyConfig.xml"));

    public final List getCompanies() {

        Command read = das.getCommand("all companies");
        DataObject root = read.executeQuery();
        return root.getList("COMPANY");

    }

    public final List getCompaniesWithDepartments() {

        Command read = das.getCommand("all companies and departments");
        DataObject root = read.executeQuery();
        return root.getList("COMPANY");
    }

    public final List getDepartmentsForCompany(int id) {
        Command read = das.getCommand("all departments for company");
        read.setParameter(1, new Integer(id));
        DataObject root = read.executeQuery();
        return root.getList("COMPANY");
    }

    public final void addDepartmentToFirstCompany() {
        Command read = das.getCommand("all companies and departments");
        DataObject root = read.executeQuery();
        DataObject firstCustomer = root.getDataObject("COMPANY[1]");

        DataObject newDepartment = root.createDataObject("DEPARTMENT");
        newDepartment.setString("NAME", "Default Name");
        firstCustomer.getList("departments").add(newDepartment);

        das.applyChanges(root);

    }

    public final void deleteDepartmentsFromFirstCompany() {

        // This section gets the ID of the first Company just so I can
        // demonstrate a parameterized command next
        Command readAll = das.getCommand("all companies and departments");
        DataObject root = readAll.executeQuery();
        int idOfFirstCustomer = root.getInt("COMPANY[1]/ID");
        System.out.println("ID of first company is: " + idOfFirstCustomer);

        // Read a specific company based on the known ID
        Command readCust = das.getCommand("company by id with departments");
        readCust.setParameter(1, new Integer(idOfFirstCustomer));
        root = readCust.executeQuery();

        // Delete all the comany's departments from the graph
        DataObject firstCustomer = root.getDataObject("COMPANY[1]");

        // Shallow copy of list for deleting. This is required to avoid the
        // dreaded
        // ConcurrentModificationException since #delete operation also removes
        // from the original list
        List allDepartments = new ArrayList(firstCustomer.getList("departments"));

        Iterator i = allDepartments.iterator();
        DataObject department;
        while (i.hasNext()) {
            department = (DataObject) i.next();
            System.out.println("Deleting department named: " + department.getString("NAME"));
            department.delete();
        }

        das.applyChanges(root);

    }

    public final void changeFirstCompanysDepartmentNames() {

        // This section gets the ID of the first Company just so I can
        // demonstrate a parameterized command next
        Command readAll = das.getCommand("all companies and departments");
        DataObject root = readAll.executeQuery();
        int idOfFirstCustomer = root.getInt("COMPANY[1]/ID");
        System.out.println("ID of first company is: " + idOfFirstCustomer);

        // Read a specific company based on the known ID
        Command readCust = das.getCommand("company by id with departments");
        readCust.setParameter(1, new Integer(idOfFirstCustomer));
        root = readCust.executeQuery();

        // Modify all the comany's department names
        DataObject firstCustomer = root.getDataObject("COMPANY[1]");
        Iterator i = firstCustomer.getList("departments").iterator();
        DataObject department;
        while (i.hasNext()) {
            department = (DataObject) i.next();
            System.out.println("Modifying department: " + department.getString("NAME"));
            department.setString("NAME", getRandomDepartmentName());
        }
        das.applyChanges(root);

    }
    
    
    public void releaseResources() {
        das.releaseResources();
    }

    // Utilities

    private String getRandomDepartmentName() {
        int number = generator.nextInt(1000) + 1;
        return "Dept-" + number;
    }

    private InputStream getConfig(String fileName) {
        return getClass().getClassLoader().getResourceAsStream(fileName);
    }

}

Create following Company.jsp file under (Tomcat root)/webapps/companyweb.

No Format

<html>
<head>
<%@ page language="java" contentType="text/html; charset=ISO-8859-1"

	pageEncoding="ISO-8859-1"

        import="org.apache.tuscany.samples.das.companyweb.CompanyClient"
        import="commonj.sdo.*"
%>

<meta http-equiv="Content-Type" content="text/html; charset=ISO-8859-1">
<title>Company Test</title>
</head>
<body>

<H2>Tuscany DAS Companies WEB Example</H2>


<form>
<input type="submit" id="doFill" name="doFill" value="All Companies">
<input type="submit" id="doFillAll" name="doFillAll" value="All Companies/Departments">
<input type="submit" id="doAddDepartment" name="doAddDepartment" value="Add department to first company">
<input type="submit" id="doChangeDepartmentNames" name="doChangeDepartmentNames" value="Change Company(1) Dept names">
<input type="submit" id="doDeleteDepartments" name="doDeleteDepartments" value="Delete Company(1) Depts">
<hr>

<!-- Do Fill -->
<%if(request.getParameter("doFill") != null){%>

<table border>
	<thead>
		<tr>
			<th>ID</th>
			<th>Name</th>
		</tr>
	</thead>
	<tbody>

		<%
		CompanyClient companyClient = new CompanyClient();
		java.util.Iterator i = companyClient.getCompaniesWithDepartments().iterator();
		while (i.hasNext()) {
			DataObject company = (DataObject)i.next();
		%>
			<tr>
				<td><%=company.getInt("ID")%></td>
				<td><%=company.getString("NAME")%></td>
			<tr>
		<%	
		}
		companyClient.releaseResources();
		%>
		
	</tbody>
</table>
<%}%>


<!-- Do Add Department -->
<%
if(request.getParameter("doAddDepartment") != null){
    CompanyClient companyClient = new CompanyClient();
    companyClient.addDepartmentToFirstCompany();
    companyClient.releaseResources();
}
%>

<!-- Do Delete Departments from first company -->
<%
if(request.getParameter("doDeleteDepartments") != null){
    CompanyClient companyClient = new CompanyClient();
    companyClient.deleteDepartmentsFromFirstCompany();
    companyClient.releaseResources();
}
%>

<!-- Do Change First Company's Department Names -->
<%
if(request.getParameter("doChangeDepartmentNames") != null){
    CompanyClient companyClient = new CompanyClient();
    companyClient.changeFirstCompanysDepartmentNames();
    companyClient.releaseResources();
}
%>


<!-- Do FillAll -->
<%if(request.getParameter("doFill") == null) {%>

<table border>
	<thead>
		<tr>
			<th>ID</th>
			<th>Name</th>
			<th>Department_ID</th>
			<th>Department_Name</th>
		</tr>
	</thead>
	<tbody>

		<%
		CompanyClient companyClient = new CompanyClient();
		java.util.Iterator i = companyClient.getCompaniesWithDepartments().iterator();
		while (i.hasNext()) {
			DataObject company = (DataObject)i.next();
		%>
			<tr>
				<td><%=company.getInt("ID")%></td>
				<td><%=company.getString("NAME")%></td>
			<tr>

			

			<%
			java.util.Iterator j = company.getList("departments").iterator();
			while (j.hasNext()) {
				DataObject department = (DataObject)j.next();
			%>
				<tr>
					<td></td><td></td><td><%=department.getInt("ID")%></td>
					<td><%=department.getString("NAME")%></td>
				<tr>
			<%	
			}
			%>
		<%	
		}
		companyClient.releaseResources();
		%>
		
	</tbody>
</table>
<%}%>

</form>
</body>
</html>

E. Creating web and context configuration files supporting Tomcat

Under WEB-INF create following web.xml file and save it.
web.xml

No Format

<?xml version="1.0" encoding="ISO-8859-1"?>
<!DOCTYPE web-app PUBLIC "-//Sun Microsystems, Inc.//DTD Web
Application 2.3//EN" "http://java.sun.com/dtd/web-app_2_3.dtd">

<web-app>
    <display-name>Tuscany DAS sample Company  WEB</display-name>

    <welcome-file-list id="WelcomeFileList">
        <welcome-file>Company.jsp</welcome-file>
    </welcome-file-list>
</web-app>

Under META-INF create following context.xml file and save it.
context.xml

No Format

<?xml version="1.0" encoding="UTF-8"?>
<Context path="/DAS Stand alone app" debug="5" reloadable="true" crossContext="true">
   <Manager pathname=""/>
   <ResourceLink name="jdbc/dastest" global="jdbc/dastest" type="javax.sql.DataSource" />                     
</Context>

Under (Tomcat root)/conf modify server.xml with following entry in <GlobalNamingResources>

No Format

<Resource name="jdbc/dastest"
type="javax.sql.DataSource"  auth="Container"
description="MySQL database for DAS Web sample"
maxActive="100" maxIdle="30" maxWait="10000"
username="" password=""
driverClassName="com.mysql.jdbc.Driver"
url="jdbc:mysql:///dastest?user=xxx&password=yyy"/>

F. Run the sample companyweb

All setup is complete now. Run the application in Tomcat and try different options like query company and
departments, addition, deletion.
How do I run this? Can you provide an example?

Child pages

Versions Compared

Old Version 11

New Version Current

Key

Starting with DAS

old guide - just to compare, can be deleted later -

A. Initial Setup

B. Creating CompanyWeb Database

C. Creating XML configuration file

D. Creating the class and jsp which manages the DAS/SDO features

E. Creating web and context configuration files supporting Tomcat

F. Run the sample companyweb

Child pages

Page History

Versions Compared

Old Version 11

New Version Current

Key

Starting with DAS

old guide - just to compare, can be deleted later -

A. Initial Setup

B. Creating CompanyWeb Database

C. Creating XML configuration file

D. Creating the class and jsp which manages the DAS/SDO features

E. Creating web and context configuration files supporting Tomcat

F. Run the sample companyweb