rakib09 / code-experiment

Learning in different topics

Code-Experiment

Learning in different topics

Java Interview Topics

Exception Handling

• Types of Exception: Runtime & Compile time exception
• Real time Examples & writing your custom exception by extending Exception & RuntimeException
• When to use which exception
• Exception Hierarchy

Collections

• List vs array vs Vectors vs Collections
• synchronized List
• HashMap vs TreeMap vs Linked Hashmap vs Concurrent HashMap vs HashTable - Difference & uses
• Creating custom hashmap and Custom Linked hashmap
• Use of Hashset and internal working
• Creating a hashmap with key as Employee Object overriding hashcode & equals
• Collision of hash map

Object Class Methods

• Overriding hash code and equals method. Contract between them and importance of it
• Comparator and Comparable- difference and when to use that, real time example
• overriding finalise
• to string method and importance

Garbage Collection

• How garbage Collection takes place. Internal working of garbage collection
• Lifecycle of objects on heap
• weak reference object
• finalise keyword and its importance

String and Immutable class

• Importance of string, and it's memory management
• use of string pool
• Difference between string, string builder and string buffer
• use of immutable classes
• Create your own custom immutable classes
• Autoboxing and Unboxing

Multi Threading

• How to create threads
• Thread lifecycle and how threads are executed by thread scheduler
• Synchronise, volatile keywords
• Intrinsic and renetrant lock use of locks
• use of wait, notify, notifyALL, join sleep methods
• Producer consumer problem using priority queue as well as using low level methods such as wait and notify

Java 8 Functional Programming

• Java-8 fundamentals
• Writing functions using lambda expression

DI and IOC

• Dependency Injection and its Type
• What is IOC?
• Scope of beans
• Annotations: @PathVariable, @RequestParam, @Autowired, @ModelAttribute, @RequestBody, @ResponseBody, @Entity
• Singleton and prototype scope difference

Aspect Oriented Programming

• Writing aspect and it's importance
• Types of advice .
• Importance of aspect

Spring MVC

• Spring MVC
• Internal working of spring MVC

Linked List

• LinkedList reversal
• Merging LinkedList
• Finding insertion point
• LinkedList cloning with random pointers
• Doubly lined list reversal

Stack and Queue

• Writing custom stack and queue
• creating stack from queue and vice versa
• Designing LRU Cache using Queue

Tree and Graph

• BFS and DFS of tree and graphs
• common ancestor problem
• BT is a bst
• Converting a sorted array to bst
• Converting bst to main and max heap

Arrays and Matrix

• Maximum contiguous sum in an array
• Count Island problem of matrix
• 000111 question of matrix
• Some db questions such as cutting problem

SQL Database: Oracle

• Writing SQl queries
• Difference between sql and nosql database and importance of both
• Why is indexing? How indexing works? How indexing helps in reducing the response time while quering
• Use of join and writing join queries

Hibernate

• Get vs Load vs Persist
• Configuration file
• 2nd level cache
• Many to many mapping
• Types of mapping
• xml based and annotation based
• Cascading in hibernate and type

Tomcat

• Version number
• Server.xml

Reference:

• Play Java