Skip to main content

JSR-168 Specification / Portal Architecture

The Portlet Specification addresses the following topics

  1. The portlet container contract 
  2. Portlet life cycle management
  3. The definition of window states
  4.  Portlet modes
  5.  Portlet preferences management
  6.  User information
  7.  Packaging and deployment
  8.  Security 
  9.  JSP tags to aid portlet development

Container Contract
The life cycle methods called directly by the container are:

  • init() 
  • destroy() 
  • processAction() 
  • render() 

In addition to the methods above, which are called directly by the container, a GenericPortlet class is provided
that implements the render() method and delegates the call to more specific methods to display the portlet based
on its mode. Developers can extend GenericPortlet and implement as many of these specialized render methods as
are necessary for their portlet. These methods are: Called by render()

Portlet Preferences
as a persistent set of name-value pairs and are referred to as portlet preferences.
the getValues() and setValues() methods respectively.
Portlets have access to the PortletPreferences object when processing requests, but may only modify preference attributes during a processAction invocation. Prior to the end of the processAction method, the store()

JSP Tag Library
A JSP Tag library is included to help display portlet pages with JSP technology. For example, a custom JSP tag
automatically declares the portlet request and response objects so they can be used within the JSP. Another JSP tag
helps construct URL’s that refer back to the portlet.



Popular posts from this blog

JPA 2 new feature @ElementCollection explained

@ElementCollection is new annotation introduced in JPA 2.0, This will help us get rid of One-Many and Many-One shitty syntax.

Example 1: Stores list of Strings in an Entity

public class Users implements Serializable {

    private static final long serialVersionUID = 1L;
    @GeneratedValue(strategy = GenerationType.AUTO)
    private Long id;
    private List<String> certifications = new ArrayList<String>();

    public Long getId() {
        return id;

    public void setId(Long id) { = id;

    public List<String> getCertifications() {
        return certifications;

    public void setCertifications(List<String> certifications) {
        this.certifications = certifications;

        Users u = new Users();
        u.getCertifications().add("Sun Certified Java Programmer");

Generated Tables

Column --> ID
    Row             1


ArrayList vs LinkedList vs HashSet Performance Comparision

ConclusionsInserting & Reading sequentially from Collection prefer LinkedList/ArrayListInserting & Reading/Deleting by Search/equals from Collection prefer HashSetInserting, ArrayList & LinkedList performs best while HashSet takes double the timeReading, HashSet performs best while ArrayList & LinkedList are marginally lessDeleting, HashSet performs 10 times better than ArrayList & ArrayList performs 4 times better than LinkedList. LinkedList is slow because of sequencial search Bottom line : unless you are not going to iterate using for(Integer i : list ) then prefer HashSet
Inserting/Reading/Deleting integer's from zero till countJDK7Collectionactioncounttime msArrayListInsert1000/1LinkedListInsert1000/1HashSetInsert1000/1ArrayListInsert100005LinkedListInsert100004HashSetInsert100007ArrayListInsert10000011LinkedListInsert10000011HashSetInsert10000021ArrayListGet/Read1000LinkedListGet/Read1000HashSetGet/Read1000ArrayListGet/Read100004LinkedListGet/Read100003Has…

Validating CSV Files

What is CsvValidator ?
  A Java framework which validates any CSV files something similar to XML validation using XSD.

Why should I use this ?
  You don't have to use this and in fact its easy to write something your own and also checkout its source code for reference.

Why did I write this ?
  Some of our projects integrate with third party application which exchanges information in CSV files so I thought of writing a generic validator which can be hooked in multiple projects or can be used by QA for integration testing.

What is the license clause ?

Are there any JUnit test cases for me checkout ?
 Yes, source

How to integrate in my existing project ?

Just add the Jar which can be downloaded from here CsvValidator.jar and you are good.

Instantiate CsvValidator constructor which takes these 3 arguements

         // filename is the the file to be validated and here is a sample         // list - defines all the fields in the above csv file ( a field has index, type, isOptional, rege…