Post on 14-Dec-2015
© Visual Patterns, Inc.
Agile Java DevelopmentWith Spring, Hibernate and Eclipse
Anil Hemrajanianil@visualpatterns.com
2© Visual Patterns, Inc.
About This Presentation
• Not a tutorial on any one technology! Overview of each technology (use website, books, etc. for details)
Downloadable code (working application) Latest buzz in the US, Europe, etc.
• End-to-end system! Requirements Architecture/design Java development and debugging Deployment Logging/monitoring Advanced considerations
• Content/format (text, graphs, code, comics)
3© Visual Patterns, Inc.
Material In This Presentation Taken Directly From My Book
Agile Java DevelopmentWith Spring, Hibernate and Eclipse
Forewords by Scott W. Ambler and Rod Johnson
1. Introduction to Agile Java Development2. The Sample Application: An Online Timesheet System3. XP and AMDD-Based Architecture and Design Modeling4. Environment Setup: JDK, Ant, and JUnit5. Using Hibernate For Persistent Objects6. Overview of the Spring Framework7. The Spring Web MVC Framework8. The Eclipse Phenomenon9. Logging, Debugging, Monitoring and Profiling10. Beyond the Basics11. What Next?12. Parting Thoughts Appendices (with lots of goodies)
available on amazon.com
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My Background (details at VisualPatterns.com)
• 20 years of experience in the IT Working with Java Technology since late 1995 as a developer,
entrepreneur, author, and trainer. Helped several Fortune 100 companies (some smaller organizations) Published a book and 30 articles Presented at conferences and seminars around the world Awards:
"Outstanding Contribution to the Growth of the Java Community"
"Best Java Client" for BackOnline (a Java-based online backup product)
nominated for a Computerworld-Smithsonian award by Scott McNealy
• Founder of: Isavix Corporation – successful IT solutions company (now Inscope
Solutions) DeveloperHub.com (formerly isavix.net) - award-winning online
developer community (grew to over 100,000 registered members)
• At present – VisualPatterns.com and AgileDraw.org
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Practical Stuff, Not Fluff!
• Recently completed project for U.S. Fortune 50 company
• Application Financial application process billions of $ every week
Clustered application (99.9% uptime required)
Used most the technologies covered in presentation(spring, hibernate, eclipse, ant, JUnit…)
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Agenda
1.Introduction to Agile Java Development2.Agile Processes3.Agile Modeling4.Agile Development
Environment Setup: Directory Structure, JDK, Ant and JUnit
Using Hibernate For Persistent Objects (Short Break) The Spring Framework The Eclipse Phenomenon! Logging, Debugging, Monitoring, and Profiling
5.Beyond The Basics
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Introduction to Agile Java Development
Assume simplicity.
Travel light.
- Agile Modeling principles: agilemodeling.com
Assume simplicity.
Travel light.
- Agile Modeling principles: agilemodeling.com
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What Is Agile Java Development? It Could Include…
1.Agile Software Lifecycle Processes (e.g. Scrum, XP, TDD)
2.Agile Architecture/Design Modeling Incremental (just-in-time) design “Good enough” diagrams Agile Model Driven Development (AMDD)
3.Agile Java Design/Development Simple design and coding! Test-driven development (TDD) Efficient frameworks and tools (Ant, JUnit, Hibernate,
Spring, Eclipse…) Plain Old Java Objects (POJOs), whenever possible
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Sample (Time Sheet) Application Used In This Presentation
BEA WebLogic Server
Objects managed by Spring IoC Container
HTTP JDBC
ViewJSP/HTML
ControllerSpring
DispatcherServlet
Web
Browser
ModelBusiness
objects,
Hibernate beans
SpringScheduler
RDBMS(Oracle)
Downloadable code: visualpatterns.com/resources.jspDownloadable code: visualpatterns.com/resources.jsp
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Agile Processes
Requirements change.
Design evolves.
Documents are seldom current.
Requirements change.
Design evolves.
Documents are seldom current.
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Some Stats by The Standish Group (standishgroup.com)
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The Solution
CHAOS Ten – Success Factorssource:
standishgroup.com
In 2001, seventeen methodologists came together to unify their methodologies under one umbrella; they jointly defined the term, Agile!
Read story at: martinfowler.com/articles/agileStory.html
In 2001, seventeen methodologists came together to unify their methodologies under one umbrella; they jointly defined the term, Agile!
Read story at: martinfowler.com/articles/agileStory.html
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AgileManifesto.org
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What Does “Agile” Exactly Mean?
The Term Agile incorporates a wide range of methods, for example:
• AM - Agile Modeling• ASD - Adaptive Software Development
• AUP - Agile Unified Process
• Crystal
• FDD - Feature Driven Development
• DSDM - Dynamic Systems Development Method
• Lean Software Development
• Scrum• Xbreed
• XP - eXtreme Programming
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Agility - All About Smaller Chunks (Shorter/Frequent Cycles)
...Iteration
0Iteration
1Iteration
n
Release 1
...
Release 2
Iteration0
Iteration1
Iterationn
...
softwaresoftware
softwaresoftware softwaresoftware softwaresoftware softwaresoftware softwaresoftware
Incrementally Build Software - Highest Priority Features First!Incrementally Build Software - Highest Priority Features First!
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Agile Method: Scrum
• Simple process for product/project management
• Product Backlog - List of known features/changes for product
• Sprint - 1-month iterations (develop highest priority items)
• Meetings Sprint Planning Meeting – Done at beginning of each sprint
(after planning, features moved from product backlog to sprint backlog)
Daily scrum meeting (short: 15 minutes) Sprint review meeting
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Extreme Programming (XP)
• Shorter and Frequent Cycles (smaller chunks!) Release - Quarterly Cycles (set a theme) Iteration - Weekly Cycles (e.g. aim for last day of week) 10-minute builds Continuous integration (multiple times per day; manual or automatic)
Incremental Design and Planning (defer investment till needed)
Development in small increments using Test-First development
• Communications - Sit Together, Informative Workspace, on-site customer
• Flow - sustainable pace versus rigid phases; velocity, continuous integration
• Others… visit extremeprogramming.org
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Presentation Outline
Introduction to Agile Java Development Agile Processes
• Agile Modeling
• Agile Development Environment Setup: Directory Structure, JDK, Ant and JUnit
Using Hibernate For Persistent Objects The Spring Framework The Eclipse Phenomenon! Logging, Debugging, Monitoring, and Profiling
• Beyond The Basics
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Agile Modeling
“...your goal is to build a shared understanding, it isn’t to write detailed documentation.”
- Scott W. Ambler
“...your goal is to build a shared understanding, it isn’t to write detailed documentation.”
- Scott W. Ambler
20© Visual Patterns, Inc.
Quick Poll
Have you ever been on a project where
documentation was kept up-to-date through end
of project?
Have you ever been on a project where
documentation was kept up-to-date through end
of project?
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Agile Model Driven Development (AMDD)
• Subset of Agile Modeling (agilemodeling.com)
• Agile version of Model Driven Development (MDD)
• Instead of extensive models, “barely good enough”
• Initial modeling activity1. Requirements
2. Architecture
• Requirements modeling Usage models Domain models UI models
• Architecture modeling Free-form diagrams Change cases
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Project Initiation
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Problem Statement
Our employees currently submit their weekly hours worked using a paper-based timesheet system that is manually intensive and error-prone.
We require an automated solution for submitting employee hours worked, in the form of an electronic timesheet, approving them, and paying for the time worked.
In addition, we would like to have automatic notifications of timesheet status changes and a weekly reminder to submit and approve employee timesheets.
Our employees currently submit their weekly hours worked using a paper-based timesheet system that is manually intensive and error-prone.
We require an automated solution for submitting employee hours worked, in the form of an electronic timesheet, approving them, and paying for the time worked.
In addition, we would like to have automatic notifications of timesheet status changes and a weekly reminder to submit and approve employee timesheets.
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Project Kickoff Meeting
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Choices Of Release (High) Level Models
Model with a purpose -- shared understanding!
domain modeldomain model user storiesuser stories UI prototype& flow map
UI prototype& flow map architecturearchitecture
ReleaseLevelModels
scope table,glossary, etc.
scope table,glossary, etc.
CRC cardsCRC cards applicationflow map
applicationflow map
UML diagrams
UML diagrams
databasemodel
databasemodel
IterationLevelModels
acceptancetests
acceptancetests
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Sample Scope Table
Shared understanding: what's in and what's out
Shared understanding: what's in and what's out
Scope Functionality Include Time Expression will provide the capability to enter, approve, and
pay for hours worked by employees.
Defer Time Expression will not calculate deductions from paychecks, such as federal/state taxes and medical expenses.
Defer Time Expression will not track vacation or sick leave.
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Domain Model
Shared understanding: business concepts > key domain objects
Shared understanding: business concepts > key domain objects
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User Stories Or Use Cases
Shared understanding: features required of software
Shared understanding: features required of software
3
XP Style User Story Card
Use Case: Login
Author Anil Hemrajani
Description This process allows User to log into the System
Actors/Interfaces • FM Trader • TheSystem
Trigger User perfor ms aLogin action
Preconditions • /N A
Success/B asic Flow 1. The System displays the Login panel prompting User forlogin details as specified i n
the 2. Usercomple tes all required fields and performs a Submit acti .on
Failure/A lternative Flow Invalid User ID /and or Password - Thesystem notifies FM trader with the message “Invalid U serID / and or Password”. The system displays the Login panel to User with the contents of all field s
.empty
Use Case - Casual, Brief or Fully Dressed
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User Interface (UI) Prototype
Shared understanding: functionality, look-and-feel, etc.
Shared understanding: functionality, look-and-feel, etc.
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UI Flow Map (Storyboard)
Shared understanding: user interface navigation/flow
Shared understanding: user interface navigation/flow
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High-Level Architecture Diagram
Shared understanding: technologies, scalability, security, reliability
Shared understanding: technologies, scalability, security, reliability
BEA WebLogic Server
Objects managed by Spring IoC
Container
HTTP JDBC
ViewJSP/HTML
ControllerSpring
DispatcherServl
et
Web
Browser
ModelBusiness
objects,
Hibernate
beans
SpringScheduler
RDBMS(Oracle)
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Shared understanding: common terminology
Shared understanding: common terminology
Glossary - List Of Common Business/Technical Terms
• AccountingThe accounting department/staff.
• ApprovedStatus of a timesheet when a Manager approves a previously submitted timesheet.
• EmployeeA person who works on an hourly basis and reports to a manager.
• PaidStatus of a timesheet when the accounting department has issued a check.
• Etc…
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Choices Of Iteration Level (Detailed) Models
domain modeldomain model user storiesuser stories UI prototype& flow map
UI prototype& flow map architecturearchitecture
ReleaseLevelModels
scope table,glossary, etc.
scope table,glossary, etc.
CRC cardsCRC cards applicationflow map
applicationflow map
UML diagrams
UML diagrams
databasemodel
databasemodel
IterationLevelModels
acceptancetests
acceptancetests
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Acceptance Tests (Serve As Detailed Requirements)
• Sign In The employee id can be up to 6 characters. The password must be between 8 and 10 characters.
Only valid users can sign in.
• Timesheet List Only a user's personal timesheets can be accessed.
• Enter Hours Hours must contain numeric data. Daily hours cannot exceed 16 hours. Weekly hours cannot exceed 96 hours.
Hours must be billed to a department. Hours can be entered as two decimal places. Employees can only view and edit their own timesheets.
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Active Stakeholder Participation (With Business Representative)
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Exploring Classes Using CRC Cards
Class Name (Noun)
Responsibilities (obligations of this class , such as business methods, exception handling, security methods, attributes/variables).
Collaborators (other classes required to provide a complete solution to a high -level requirement)
TimesheetManager
Fetches timesheet(s) from database
Saves timesheet to database
Timesheet
Timesheet
Knows of period ending date
Knows of time
Knows of department code
domain model
Timesheet List screen
First, let's reflect on what we know, domain model, UI and architecture
Second, let's explore classes on CRC cards using both as input models
free-form architecture
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Application Flow Map (Home Grown Artifact)
• Complementary to class diagrams and CRC cards
• Can be extended using CRUD columns
Story Tag View Controller Class Collaborators Tables Impacted
Timesheet List
timesheetlist TimeSheetListController TimesheetManager Timesheet
Enter Hours
enterhours EnterHoursController TimesheetManager Timesheet
Department
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UML Class and Package Diagrams
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Focus Is On Working Software vs. Comprehensive Documentation
“…your goal is to build a shared understanding, it isn’t to write detailed documentation.”
- Scott W. Ambler
“…your goal is to build a shared understanding, it isn’t to write detailed documentation.”
- Scott W. Ambler
Physical Models
CRC cardsCRC cards
applicationflow map
applicationflow map UML
diagrams
UML diagrams
databasemodel
databasemodel
acceptancetests
acceptancetests
Conceptual Models
user storiesuser stories
architecturearchitecture
problemstatement
domain modeldomain modelscopetable
scopetable
glossaryglossary
UI prototype& flow map
UI prototype& flow map
Implementation
Data BaseData Base Code BaseCode Base
THE FINAL AND LASTING ARTIFACTS!
UIprototypes
UIprototypes
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Shifting Some Upfront Design to Refactoring
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Shifting Some Upfront Design To Refactoring (Continuous Design)• Refactoring is not a new concept; the term is relatively new
• refactoring.com “Refactoring is a disciplined technique for restructuring an existing body of code, altering its internal structure without changing its external behavior.”- Martin Fowler
Over 100 refactoring techniques; for example: Extract superclass Extract interface Move class Move method
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Agile Draw - Elegantly Simple Modeling Technique
UI Flow Map
Conceptual Class Diagram
Visit AgileDraw.org Visit AgileDraw.org
High-Level Architecture
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Presentation Outline
Introduction to Agile Java Development Agile Processes Agile Modeling
• Agile Development Environment Setup: Directory Structure, JDK, Ant and JUnit
Using Hibernate For Persistent Objects The Spring Framework The Eclipse Phenomenon! Logging, Debugging, Monitoring, and Profiling
• Beyond The Basics
© Visual Patterns, Inc.
Agile Java Development:
Environment Setup (Directory Structure, JDK, Ant, and
JUnit)
45© Visual Patterns, Inc.
Quick Poll
How many of you are using Ant, JUnit,
Maven, Cruise Control, etc?
How many of you are using Ant, JUnit,
Maven, Cruise Control, etc?
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Personal Opinion:
Early Environment
Setup Is Essential
Involves more than people expect/plan
Cycle 0• Get minimal environment setup (scripts, directory, version control, etc.)
• Get end-to-end demo working Helps team
Involves more than people expect/plan
Cycle 0• Get minimal environment setup (scripts, directory, version control, etc.)
• Get end-to-end demo working Helps team
47© Visual Patterns, Inc.
Directory Structure, Naming Conventions, Version Control, etc.
➔controller/TimesheetListController.java➔model/Timesheet.java➔model/TimesheetManager.java➔test/TimesheetListControllerTest.java➔test/TimesheetManagerTest.java➔view/timesheetlist.jsp
48© Visual Patterns, Inc.
Ant (ant.apache.org)
• Ant task types Compile tasks (that is,
javac) Deployment tasks File tasks such as copy,
delete, move, and others. Property tasks for
setting internal variables
Audit/coverage tasks Database tasks Documentation tasks Execution tasks Mail tasks Preprocess tasks Property tasks Remote tasks Miscellaneous tasks (e.g.
echo)
<ftp server="mirrors.kernel.org" action="get" remotedir="/gnu/chess" userid="anonymous" password="guest@guest.com" verbose="yes" binary="yes"> <fileset file="README.gnuchess"/></ftp>
<ftp server="mirrors.kernel.org" action="get" remotedir="/gnu/chess" userid="anonymous" password="guest@guest.com" verbose="yes" binary="yes"> <fileset file="README.gnuchess"/></ftp>
<mail tolist="friend@somehost.com" subject="Hello!" from="me@myhost.com" mailhost="myhost.com" user="myuserid" password="mypassword"/>
<mail tolist="friend@somehost.com" subject="Hello!" from="me@myhost.com" mailhost="myhost.com" user="myuserid" password="mypassword"/>
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JUnit (junit.org)
• Originally written by Erich Gamma (Gang of Four, Design Patterns) Kent Beck (author of Extreme Programming and Test Driven Development)
• Simple framework – various assert methods assertEquals assertFalse assertNotNull assertNotSame assertNull assertSame assertTrue
public class SimpleTest extends junit.framework.TestCase{ int value1 = 2, value2 = 3, expectedResult = 5;
public static void main(String args[]) { junit.textui.TestRunner.run(suite()); }
public static Test suite() { return new TestSuite(SimpleTest.class); }
public void testAddSuccess() { assertTrue(value1 + value2 == expectedResult); }}
public class SimpleTest extends junit.framework.TestCase{ int value1 = 2, value2 = 3, expectedResult = 5;
public static void main(String args[]) { junit.textui.TestRunner.run(suite()); }
public static Test suite() { return new TestSuite(SimpleTest.class); }
public void testAddSuccess() { assertTrue(value1 + value2 == expectedResult); }}
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JUnit GUI Based Testing
Console Runner
Eclipse Plug-in
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Agile Method: Test Driven Development (TDD) w/ JUnit• A term coined by Kent Beck
• Also, a XP practice (test-first)
• “Red - Green - Refactor”
• Several benefits to this approach: Minimal code written to satisfy requirements (nothing more, nothing less!) If code passes the unit tests, it is done! Can help design classes better (from a client/interface perspective) Refactor with confidence
Write unit test code
More unit test code
More unit test code
Write some actual code
More actual code
More actual code
Write Test First Code, Compile, Test
52© Visual Patterns, Inc.
Presentation Outline
Introduction to Agile Java Development Agile Processes Agile Modeling
• Agile Development Environment Setup: Directory Structure, JDK, Ant and JUnit
Using Hibernate For Persistent Objects The Spring Framework The Eclipse Phenomenon! Logging, Debugging, Monitoring, and Profiling
• Beyond The Basics
© Visual Patterns, Inc.
Agile Java Development:
Using Hibernate For Persistent Objects
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Quick Poll
What persistence solution does your project use (e.g. JDBC, ORM, entity
bean)?
What persistence solution does your project use (e.g. JDBC, ORM, entity
bean)?
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Where Hibernate Fits Into Our Architecture
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An Overview of Object-Relational Mapping (ORM)
• ORM - Java object to database table/record mapping Java = objects database = relational
• Relationships unidirectional and bidirectional relations in a relational database are bidirectional by
definition
• Cardinality (OO term is multiciplicity) One-to-one one-to-many many-to-one and many-to-many
• Object Identity
• Cascade
• Others…
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Hibernate Basics
• Dialect(DB2, Microsoft SQL Server, MySQL, Oracle, PostgreSQL, SAP DB, Sybase, TimesTen…)
• SessionFactory, Session, and Transaction
• Work with Database Records (as Java Objects)
• Object States - persistent, detached, and transient
• Data Types – more than you'll likely need!
• Hibernate Query Language (HQL) – powerful SQL-like language
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From Domain Model To A (Denormalized) Physical Data Model
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Working With Hibernate - Simple Example Using Department1.hibernate.cfg.xml – Hibernate configuration file
(DB configuration)<mapping resource="Department.hbm.xml" />
2.Department.hbm.xml – Mapping file for our Department table<class name="com.visualpatterns.timex.model.Department" table="Department"> <id name="departmentCode" column="departmentCode"> <property name="name" column="name"/>
3.Department.java – Bean file with two variables: String departmentCode; String name;
4.HibernateTest.java – Simple test program (on next slide)
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HibernateTest.java
SessionFactory sessionFactory = new Configuration().configure() .buildSessionFactory();Session session = sessionFactory.getCurrentSession();
Transaction tx = session.beginTransaction();Department department = (Department)
session.get(Department.class, "IT");
System.out.println("Name for IT = " + department.getName());
...
List departmentList = session.createQuery("from Department").list();for (int i = 0; i < departmentList.size(); i++){ department = (Department) departmentList.get(i); System.out.println("Row " + (i + 1) + "> " + department.getName() + " (" + department.getDepartmentCode() + ")");}
...sessionFactory.close();
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Other Hibernate Features
• Saving (save, merge, saveOrUpdate)session.saveOrUpdate(timesheet)
• Deleting records session.delete(Object), or session.createQuery("DELETE from Timesheet")
• Queries using Criteria interface (more OO and typesafe) List timesheetList =
session.createCriteria(Timesheet.class) .add(Restrictions.eq("employeeId", employeeId)) .list();
Related classes: Restrictions, Order, Junction, Distinct, and others
• Locking Objects (Concurrency Control)
• Lots More Hibernate (associtions, annotations, filters, interceptors, scrollable iterations, native SQL, transaction management, etc.)
62© Visual Patterns, Inc.
Presentation Outline
Introduction to Agile Java Development Agile Processes Agile Modeling
• Agile Development Environment Setup: Directory Structure, JDK, Ant and JUnit
Using Hibernate For Persistent Objects The Spring Framework The Eclipse Phenomenon! Logging, Debugging, Monitoring, and Profiling
• Beyond The Basics
© Visual Patterns, Inc.
Agile Java Development:
The Spring Framework
64© Visual Patterns, Inc.
Spring Modules
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Spring Java Packaging (org.springframework.)
© Visual Patterns, Inc.
Quick Poll
Are you familiar with Inversion of Control
(IoC)?
Are you familiar with Inversion of Control
(IoC)?
67© Visual Patterns, Inc.
• Dependency Injection Styles Two Supported By Spring:
Setter/getter based Constructor based
Fowler suggests a 3rd, interface injection, http://www.martinfowler.com/articles/injection.html
• Spring IoC Concepts: Beans, BeanFactory, ApplicationContext…
IoC Container And Dependency Injection Pattern
public class A{ B myB = new B(); C myC = new C();}
public class A{ B myB; C myC;
public setB(B myB) public setC(C myC)
Class A
Class CClass B
IOCContainer
Normal Way Using IoC
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Benefits of Using Spring
• Light weight Inversion of Control (IoC) container
• Excellent support for POJOs (e.g. declarative transaction management)
• Modular – not an all-or-nothing approach
• Testing – dependency injection and POJOs makes for easier testing
• Many others No Singletons Builds on top of existing technologies (e.g. JEE, Hibernate)
Robust MVC web framework Consistent database exception hierarchy (e.g. wrap SQLException)
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Where Spring Framework Fits Into Our Architecture
OptionalHibernate integration
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Quick Poll
Which web framework do you use?
Which web framework do you use?
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Spring Web MVC
• Easier testing – mock classes, dependency injection
• Bind directly to business objects
• Clear separation of roles – validators, adaptable controllers, command (form) object, etc.
• Simple but powerful tag libraries
• Support for various view technologies and web frameworks (e.g. Struts, webwork, tapestry, JSF)
72© Visual Patterns, Inc.
Spring MVC Java Concepts
1.Controller
2.ModelAndView
3.Command (Form Backing) Object
4.Validator
5.Spring Tag Library (spring:bind)
73© Visual Patterns, Inc.
<bean id="urlMapAuthenticate” class= "org.springframework.web.servlet.handler.SimpleUrlHandlerMapping"> <prop key="/enterhours.htm">enterHoursController</prop>...
<bean id="viewResolver"class="org.springframework.web.servlet.view.InternalResourceViewResolver"> <property name="viewClass"> <value>org.springframework.web.servlet.view.JstlView</value> </property> <property name="prefix"> <value>/WEB-INF/jsp/</value> </property> <property name="suffix"> <value>.jsp</value> </property></bean>
<bean id="urlMapAuthenticate” class= "org.springframework.web.servlet.handler.SimpleUrlHandlerMapping"> <prop key="/enterhours.htm">enterHoursController</prop>...
<bean id="viewResolver"class="org.springframework.web.servlet.view.InternalResourceViewResolver"> <property name="viewClass"> <value>org.springframework.web.servlet.view.JstlView</value> </property> <property name="prefix"> <value>/WEB-INF/jsp/</value> </property> <property name="suffix"> <value>.jsp</value> </property></bean>
Spring MVC Configuration
<servlet> <servlet-name>timex</servlet-name> <servlet-class> org.springframework.web.servlet.DispatcherServlet </servlet-class> <load-on-startup>1</load-on-startup></servlet><servlet-mapping> <servlet-name>timex</servlet-name> <url-pattern>*.htm</url-pattern></servlet-mapping>
<servlet> <servlet-name>timex</servlet-name> <servlet-class> org.springframework.web.servlet.DispatcherServlet </servlet-class> <load-on-startup>1</load-on-startup></servlet><servlet-mapping> <servlet-name>timex</servlet-name> <url-pattern>*.htm</url-pattern></servlet-mapping>
timex-servlet.xml
web.xml
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Sample End-To-End Flow Using Spring and Hibernate
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Timesheet List: A No-Form Controller Example
public class TimesheetListController implements Controller {... public ModelAndView handleRequest( HttpServletRequest request, HttpServletResponse response)
mockHttpServletRequest = new MockHttpServletRequest("GET", "/timesheetlist.htm");ModelAndView modelAndView = timesheetListController.handleRequest( mockHttpServletRequest, null);
assertNotNull(modelAndView);assertNotNull(modelAndView.getModel());
mockHttpServletRequest = new MockHttpServletRequest("GET", "/timesheetlist.htm");ModelAndView modelAndView = timesheetListController.handleRequest( mockHttpServletRequest, null);
assertNotNull(modelAndView);assertNotNull(modelAndView.getModel());
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Enter Hours: A Form Screen
public class EnterHoursController extends SimpleFormControllerpublic class EnterHoursController extends SimpleFormController
1. EnterHoursController.java2. EnterHoursValidator.java3. enterhours.jsp
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View/JSP Code – Spring and JSTL Tag Libraries
<spring:bind path="command.employeeId"> <input name='<c:out value="${status.expression}"/>' value='<c:out value="${status.value}"/>' type="text" size="6" maxlength="6"></spring:bind>
<spring:bind path="command.employeeId"> <input name='<c:out value="${status.expression}"/>' value='<c:out value="${status.value}"/>' type="text" size="6" maxlength="6"></spring:bind>
Special (Spring) variable named status• status.value• status.expression• status.error• status.errorMessage• status.errorMessages• status.displayValue
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public class HttpRequestInterceptor extends HandlerInterceptorAdapter{ public boolean preHandle(HttpServletRequest request, HttpServletResponse response, Object handler) { if (!signedIn) { response.sendRedirect(this.signInPage); return false; }
public class HttpRequestInterceptor extends HandlerInterceptorAdapter{ public boolean preHandle(HttpServletRequest request, HttpServletResponse response, Object handler) { if (!signedIn) { response.sendRedirect(this.signInPage); return false; }
Sign In (Authentication) - Spring HandlerInterceptor
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Other Spring Web Stuff
• View with no controllers (e.g. only JSP files)<bean id="urlFilenameController"
class="org.springframework.web.servlet.mvc.UrlFilenameViewController"/><prop key="/help.htm">urlFilenameController</prop>
• Spring 2.0 – new tag libraries form:form - org.springframework.web.servlet.tags.form.FormTag form:input- org.springframework.web.servlet.tags.form.InputTag form:password -
org.springframework.web.servlet.tags.form.PasswordInputTag form:hidden -
org.springframework.web.servlet.tags.form.HiddenInputTag form:select -
org.springframework.web.servlet.tags.form.SelectTag form:option -
org.springframework.web.servlet.tags.form.OptionTag form:radiobutton -
org.springframework.web.servlet.tags.form.RadioButtonTag Others…
• Other Web Flow – gaining a lot of momentum! Wizard-like features.
Portlet API – based on JSR-168 Portlet Specification (jcp.org).
80© Visual Patterns, Inc.
Spring ORM Module: Support for Hibernate
• Management of sessionfactory and session (no close calls)
• Declarative transaction management in light-weight containers
• Easier testing (pluggable Sessionfactory via XML file)
• Less lines of code – focus on business logic!
81© Visual Patterns, Inc.
Spring ORM Module: Support for Hibernate (cont’d)
Less lines of code
File Programmatic Declarative DepartmentManager.java 39 22 EmployeeManager.java 66 36 TimesheetManager.java 166 87 TOTAL 271 145
Session session = HibernateUtil.getSessionFactory().getCurrentSession();session.beginTransaction();try{ session.saveOrUpdate(timesheet); session.getTransaction().commit();}catch (HibernateException e){ session.getTransaction().rollback(); throw e;}
Session session = HibernateUtil.getSessionFactory().getCurrentSession();session.beginTransaction();try{ session.saveOrUpdate(timesheet); session.getTransaction().commit();}catch (HibernateException e){ session.getTransaction().rollback(); throw e;}
getHibernateTemplate().saveOrUpdate(timesheet);getHibernateTemplate().saveOrUpdate(timesheet);
82© Visual Patterns, Inc.
More Spring…
• Scheduling Jobs (with Quartz or JDK timers)
• Spring email support
• Much more JEE support Sub-projects (Acegi, BeanDoc, Spring IDE, etc.)
<bean id="reminderEmailJobDetail" class="org.springframework.scheduling.quartz.MethodInvokingJobDetailFactoryBean"> <property name="targetObject" ref="reminderEmail" /> <property name="targetMethod" value="sendMail" /></bean>
<bean id="reminderEmailJobTrigger" class="org.springframework.scheduling.quartz.CronTriggerBean"> <property name="jobDetail" ref="reminderEmailJobDetail" /> <property name="cronExpression" value="0 0 14 ? * 6" /></bean>
<bean id="reminderEmailJobDetail" class="org.springframework.scheduling.quartz.MethodInvokingJobDetailFactoryBean"> <property name="targetObject" ref="reminderEmail" /> <property name="targetMethod" value="sendMail" /></bean>
<bean id="reminderEmailJobTrigger" class="org.springframework.scheduling.quartz.CronTriggerBean"> <property name="jobDetail" ref="reminderEmailJobDetail" /> <property name="cronExpression" value="0 0 14 ? * 6" /></bean>
83© Visual Patterns, Inc.
Presentation Outline
Introduction to Agile Java Development Agile Processes Agile Modeling
• Agile Development Environment Setup: Directory Structure, JDK, Ant and JUnit
Using Hibernate For Persistent Objects The Spring Framework The Eclipse Phenomenon! Logging, Debugging, Monitoring, and Profiling
• Beyond The Basics
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Agile Java Development:
The Eclipse Phenomenon!
85© Visual Patterns, Inc.
Quick Poll
Which IDE do you use?Which IDE do you use?
86© Visual Patterns, Inc.
The Eclipse Foundation, Platform and Projects
• Foundation Originally developed by Object Technology International (OTI), purchased by IBM ($40 million) and donated it to open source!
Recruited various corporations; from eclipse.org: Industry leaders Borland, IBM, MERANT, QNX Software Systems, Rational Software, Red Hat, SuSE, TogetherSoft and Webgain formed the initial eclipse.org Board of Stewards in November 2001. By the end of 2003, this initial consortium had grown to over 80 members.
My view: Eclipse foundation is similar to Apache foundation for GUI tools
• Platform objectives robust platform for highly integrated dev tools enable view and/or editing of any content type attract a large community of developers to develop plug-ins
• ProjectsApplication Development, editors, modeling, performance, testing, reporting, and many more
87© Visual Patterns, Inc.
Many Platforms Supported (Windows, Unix, Linux, Mac OS X…)
88© Visual Patterns, Inc.
Personal Opinion:
The Java versus
Microsoft Thing
First exciting IDE Huge community - Plug-ins galore
(thousand+) Ward Cunningham and Erich Gamma Battle of IDEs has only now begun!
First exciting IDE Huge community - Plug-ins galore
(thousand+) Ward Cunningham and Erich Gamma Battle of IDEs has only now begun!
89© Visual Patterns, Inc.
Eclipse Basic Concepts
1. Workspace (directory of projects)
2. Workbench3. Perspectives4. Editors and Views5. Project6. Wizards (hundreds)
7. Plug-ins (galore!)
sample workspace
90© Visual Patterns, Inc.
Project/Plug-in: Java Development Tools (JDT)
• Java views (e.g. packages, types, members)
• Intelligent code fix and content assist
• Compile during save (within the blink of an eye)
• Powerful debugger (than works!)
• Pre-configured for JUnit and Ant
• Others Formatting options Powerful search Code refactoring (some based on Fowler's refactoring.com)
TODO lists Scrapbook Export feature (create zip files, etc.)
91© Visual Patterns, Inc.
JDT Features
Ant Assist
Java Browsing
Java Compile Errors/Warnings
JUnit
92© Visual Patterns, Inc.
Project/Plug-ins: Eclipse Web Tools Platform (WTP)
• Tools for developing J2EE Web applications
• Editors Source - HTML, JavaScript, CSS, JSP, SQL, XML, DTD, XSD, and WSDL
Graphical - XSD and WSDL
• Database access and query tools and models
• Web service wizards
• J2EE - project natures, builders, models navigator
© Visual Patterns, Inc.
WTP Web Services Related Screens
94© Visual Patterns, Inc.
Other WTP Features
Database
Servers
JSP Assist
95© Visual Patterns, Inc.
CVS (Eclipse Team Sharing)
96© Visual Patterns, Inc.
Hibernate and Spring Plug-Ins
Hibernate
Spring IDE
97© Visual Patterns, Inc.
Startup Time Comparison To IntelliJ and NetBeans
IntellIJ - 1 minute, 5 seconds!
Eclipse with JDT, WTP, Hibernate, Eclipse... 19 seconds!
Eclipse with JDT, WTP, Hibernate, Eclipse... 19 seconds!
NetBeans - 42 seconds.
98© Visual Patterns, Inc.
Presentation Outline
Introduction to Agile Java Development Agile Processes Agile Modeling
• Agile Development Environment Setup: Directory Structure, JDK, Ant and JUnit
Using Hibernate For Persistent Objects The Spring Framework The Eclipse Phenomenon! Logging, Debugging, Monitoring, and Profiling
• Beyond The Basics
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Agile Java Development:
Logging, Debugging, Monitoring, and Profiling
100© Visual Patterns, Inc.
Quick Poll
Do you use a GUI debugger? Or, a logging framework?
Or, use println statements?
Do you use a GUI debugger? Or, a logging framework?
Or, use println statements?
101© Visual Patterns, Inc.
Logging Basics and Frameworks
• Types1.Audit log2.Tracing3.Error reporting
• Pros• No human intervention (automated)
• Great for head-less servers
• Cons• Performance hit
• Can clutter code
import org.apache.commons.logging.Log;import org.apache.commons.logging.LogFactory;
public class CommonsLoggingTest{ private static Log log = LogFactory.getLog(CommonsLoggingTest.class);
public static void main(String[] args) { log.fatal("This is a FATAL message."); log.error("This is an ERROR message."); log.warn("This is a WARN message."); log.info("This is an INFO message."); log.debug("This is a DEBUG message."); }}
Logging Frameworks
• Alternative to println statements
• Key benefit - Output control (destination, format, log level)
• Most popular - Apache Log4J and JDK Logging
• Jakarta Commons Logging -- bridge to frameworks
102© Visual Patterns, Inc.
Headaches of Finding and Fixing Bugs!
103© Visual Patterns, Inc.
Debugging Java Code With Eclipse
• Debug perspectives
and views
• Breakpoints
• Step through code
• Variable inspection
• Hotswap
• Remote debugging
“consolidated debugging”
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Debugging Web User Interfaces Using Mozilla Firefox
JavaScript debugger
Web Developer
Tamper Data
105© Visual Patterns, Inc.
Java Monitoring and Profiling
• Monitoring JSE 5.0 includes JConsole
Memory issues Class loading and garbage collection
Management of MBeans and JDK logging level, etc …
• Profiling Memory usage and leaks
CPU utilization Trace objects and methods
Determine performance bottlenecks
<bean id="timexJmxBean” class= "com.visualpatterns.timex.util.TimexJmxBean" />
<bean id="exporter” class= "org.springframework.jmx.export.MBeanExporter"> <property name="beans"> <map> <entry key="Time Expression:name=timex-stats" value-ref="timexJmxBean" />
<bean id="timexJmxBean” class= "com.visualpatterns.timex.util.TimexJmxBean" />
<bean id="exporter” class= "org.springframework.jmx.export.MBeanExporter"> <property name="beans"> <map> <entry key="Time Expression:name=timex-stats" value-ref="timexJmxBean" />
Spring MBean Exporter
106© Visual Patterns, Inc.
Presentation Outline
Introduction to Agile Java Development Agile Processes Agile Modeling Agile Development
Environment Setup: Directory Structure, JDK, Ant and JUnit
Using Hibernate For Persistent Objects The Spring Framework The Eclipse Phenomenon! Logging, Debugging, Monitoring, and Profiling
• Beyond The Basics
© Visual Patterns, Inc.
Beyond The Basics
108© Visual Patterns, Inc.
Custom Tag Libraries
public class PayPeriodCheckTag extends TagSupport{ public int doStartTag() throws JspException { boolean includeText = ; // do something if (includeText) return TagSupport.EVAL_BODY_INCLUDE; return TagSupport.SKIP_BODY; }
<timex:periodcheck checkDate="${command.periodEndingDate}"> <input name="save" type="submit" value="Save"></timex:periodcheck>
<timex:periodcheck checkDate="${command.periodEndingDate}"> <input name="save" type="submit" value="Save"></timex:periodcheck>
109© Visual Patterns, Inc.
Security, Reliability and Scalability Considerations
110© Visual Patterns, Inc.
Application Security Considerations
• Authentication (user and application levels)
• Authorization (roles, groups, etc.)
• Encryption (wire protocol, configuration files)
Wire protocol (HTTP/S)
User-level authenticati
on & authorizatio
n
Application-level
authentication
111© Visual Patterns, Inc.
Other Considerations
• Exception Handling1. Checked exceptions (e.g. IOException) – required catch or throw
2. Unchecked exceptions (e.g. NullPointerException) - no catch/throw needed
3. Errors (e.g. OutOfMemoryError)
• Clustering (serialize, no static variables, simplicity…)
• Multi-threading (JDK 1.5 concurrent API)
• Rich Internet Applications (RIA) AJaX -
Google Web Toolkit (GWT) - http://code.google.com/webtoolkit/
Direct Web Remoting (DWR) - http://getahead.ltd.uk/dwr/
Adobe Flex Java Swing and Web Start
112© Visual Patterns, Inc.
Cool Concept For Smaller Apps - Entire System In A WAR File!• Code (source, binary)
• Relational database (e.g. HSQLDB)
• Job Scheduling
• More…
© Visual Patterns, Inc.
Wrap Up!
© Visual Patterns, Inc.
Presentation Outline
Introduction to Agile Java DevelopmentAgile ProcessesAgile ModelingAgile Development
Environment Setup: Directory Structure, JDK, Ant and JUnit
Using Hibernate For Persistent Objects The Spring Framework The Eclipse Phenomenon! Logging, Debugging, Monitoring, and Profiling
Beyond The Basics
115© Visual Patterns, Inc.
Constant Learning – Be a “Generalizing Specialist”
116© Visual Patterns, Inc.
Don’t Forget - Release Completion Celebration!
RONRON STEVESTEVE RAJRAJ SUSANSUSAN
© Visual Patterns, Inc.
Some Near Term Plans
118© Visual Patterns, Inc.
Book - Released 12th May, 2006
Agile Java DevelopmentWith Spring, Hibernate and Eclipse
Forewords by Scott W. Ambler and Rod Johnson
1. Introduction to Agile Java Development2.2. The Sample Application: An Online The Sample Application: An Online Timesheet SystemTimesheet System3.3. XP and AMDD-Based Architecture and XP and AMDD-Based Architecture and Design ModelingDesign Modeling4. Environment Setup: JDK, Ant, and JUnit5. Using Hibernate For Persistent Objects6. Overview of the Spring Framework7. The Spring Web MVC Framework8. The Eclipse Phenomenon9. Logging, Debugging, Monitoring and Profiling10. Beyond the Basics11. What Next?12. Parting Thoughts Appendices (with lots of goodies)
available on amazon.com
119© Visual Patterns, Inc.
Interesting Stuff At VisualPatterns.com - Visit Site Periodically
Planning Coding • User stories are written. • Release planning creates the
schedule. • Make frequent small releases. • The Project Velocity is measured. • The project is divided into iterations. • Iteration planning starts each
iteration. • Move people around. • A stand-up meeting starts each day. • Fix XP when it breaks.
• The customer is always available. • Code must be written to agreed
standards. • Code the unit test first. • All production code is pair programmed. • Only one pair integrates code at a time. • Integrate often. • Use collective code ownership. • Leave optimization till last. • No overtime.
Designing Testing • Simplicity. • Choose a system meta phor. • Use CRC cards for design sessions. • Create spike solutions to reduce risk. • No functionality is added early. • Refactor whenever and wherever
possible.
• All code must have unit tests. • All code must pass all unit tests before it
can be released. • When a bug is found tests are created. • Acceptance tests are run often and the
score is published.
ComicsCheat Sheets
R&D Concepts
120© Visual Patterns, Inc.
THE END!
• agilemodeling.com
• agiledata.org
• agilemanifesto.org
• extremeprogramming.org
• hibernate.org
• springframework.org
• eclipse.org
• code.google.com/webtoolkit/
• getahead.ltd.uk/dwr/
• VisualPatterns.com (links, comics, code, cheat sheets…)
Stay in touch!
Anil@VisualPatterns.com
Stay in touch!
Anil@VisualPatterns.com