Session Tracking in JSP


Java EE Tutorials JSP Tutorials Recommended Books for Java Server Pages (JSP) Sessions are mechanism for storing client data across multiple HTTP requests. From one request to another user the HTTP server does not maintain a reference or keep any record of client previous request. HttpSession Methods getAttribute : it returns stored value from session […]

TreeSet in Java


TreeSet class implements the Set interface and stores the data in tree structure. The values are stored in sorted and ascending oreder. It is quite fast in retrieval of elements. This makes TreeSet is most prefered choice for storing the large amount of data in sorted order and want to retrieve it fast. This supports […]

How To Sort Java Object Using Comparable And Comparator?


This tutorial shows how to use java.util.Comparator and java.lang.Comparable to sort a Java object based on its property value. Here I have created Employee object with Name and Age properties, we will be able to sort the list of objects based on the values in the property’ Lets look at the example. Output […]

HashTable in Java


HashTable class was originally added as part of java.utill package and extended the Dictionary class. From Java 2, it is re-engineered to implement the Map interface and made as part of the collections framework. HashTable is similar to HashMap except that HashTable is synchronized. It is very much similar to HashMap, stores the key-value pairs. […]

HashMap in Java


HashMap uses the hash table to implement the Map interface. Map is key-value pair where key is the reference and value is the actual data. HashMap is very extensively used in the projects when key-value type data is stored. This doesn’t ensure the order of insertion. This class extends the AbstractMap and implements the Map […]

HashSet in Java


HastSet is one of the classes available with collections package and it extends the AbstractSet and implements the Set interface. This uses the hash table for storing the values. Hash table internally using hashing mechanism to store the values. In the hashing technique, information is uniquely identified using the hash code. HashSet supports four constructors. […]

LinkedList in Java


LinkedList is not most commonly used class for storing the values. The LinkedList class extends AbstractSequentialList and implements the List interface. It stores the data using linked-list data structure. This class has two constructors, With empty parameters – LinkedList() and With Collection object as the parameter – LinkedList (Collection c) Some of the important features of […]



Java EE Tutorials JSP Tutorials Recommended Books for Java Server Pages (JSP) This tutorial lists down the API’s used in the Java Server Pages (JSP) programming. API stands for Application Programming Interface that allows programmers for building software applications in java. JSP API is categorized into following packages: Packages Description javax.el It provides classes and interfaces […]

JSP Redirect


Java EE Tutorials JSP Tutorials Recommended Books for Java Server Pages (JSP) Redirect is used to move or redirect response to another resource. The resource may be servlet , jsp or html file. In this tutorial we will see an example of how to redirect in JSP. We can do PageRedirect using the sendRedirect() method, which […]

OCPJP 6 Mock Exam -15


1 . Which of the following can prevent a thread from executing? A call to its pause method A call to Thread.yield() Another thread is given higher priority A call to its halt() method 2 . Which of the following represent correct syntax for assertions? assertion(b==false); assert (b==false); assert() b==false; if(b!=true) assert; 3 . What […]