Spring MVC Framework and REST Spring’s annotation-based MVC framework simplifies the process of creating RESTful web services. The key difference between a traditional Spring MVC controller and the RESTful web service…
A priority queue in Java is a special type of queue wherein all the elements are ordered as per their natural ordering or based on a custom Comparator supplied at the time of creation. The front of the…
A Queue is a First In First Out (FIFO) data structure. It models a queue in real-life. Yes, the one that you might have seen in front of a movie…
Lambda expressions were introduced in Java 8 and they became the talk of the town as soon as they arrived. Java has evolved a lot with time. It has incorporated…
Java LinkedList is a doubly linked list implementation of Java’s List and Deque interfaces. It is part of Java’s collections framework. Here is the class hierarchy of LinkedList Following are some key…
Given n pairs of parentheses, write a function to generate all combinations of well-formed parentheses. For example, given n = 3, a solution set is: "((()))", "(()())", "(())()", "()(())", "()()()"…
Longest Substring with Repeating Characters - Find the length of the longest substring T of a given string (consists of lowercase letters only) such that every character in T appears…
Given a string containing just the characters '(' and ')', find the length of the longest valid (well-formed) parentheses substring. For "(()", the longest valid parentheses substring is "()", which…
Given a string containing just the characters '(', ')', '{', '}', '[' and ']', determine if the input string is valid. The brackets must close in the correct order, "()"…
A diagram is sometimes worth 1000 words. The following diagrams are from Java tutorials on Program Creek, they have received the most votes so far. Hopefully, they can help you review what…