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00: How to prepare to succeed in Java job interviews?

“Why wait 5 to 10 years when you can fast-track & go places in 1-2 years”

Relying only on your experience can take a long time to get a good handle …


00: Why favor composition over inheritance?

This not only one of the most popular Java OOP Interview Questions & Answers asked 90% of the time in job interview, but also a key OOP concept you must know …


01: 9 Java low latency interview questions & answers

Trading Execution reports are received and processed asynchronously

Have you seen job advertisements requiring Java candidates to work in low latency, high throughput, real-time and distributed systems with share-nothing architectures? Wondering what questions you will be asked? …


01: jvisualvm tutorial to sample Java heap memory

Java does not have a sizeof operator like C++ does. Java uses automatic memory management known as the Garbage Collection, hence it is not that important to evaluate size of various …


01: Q13 “12 Rules” for REST API design & development

These are more like rules to develop RESTFul web services as opposed to being the best practices. REST is an architectural style without any contracts or specifications. So, it is imperative …


02: 15 key considerations for low latency Java

Extends Writing low latency applications in Java interview Q&As. If the job description says “low latency” application, then be prepared. Even if “low latency” experience is not a requirement, all employers …


02: 5 Java multithreading scenarios interview

Java interview questions & answers on multithreading scenarios to judge your experience in building applications with concurrency in mind. Q1. Can you give some scenarios where you built concurrent systems? A1. …


02: HTTP basics on headers, MIME types, & cookies for Java developers

Q1. What happens when you open up a browser and type a URL to request a Web page or RESTFul web service data? A1. HTTP is a stateless protocol on top …


02: jvisualvm to detect memory leak – a quick tutorial style Java demo

This is a companion post to 8 Java Memory Management Interview Q&A demonstrating a memory leak scenario step by step with jvisualvm, which is a free profiling tool that gets shipped …


03: Identifying and fixing NonUniqueObjectException in Hibernate

Hibernate NonUniqueObjectException

NonUniqueObjectException is thrown when there is an object already associated with the session with the same id (primary key) (i.e. a duplicate). It is important to understand the concept of a …


03: Java GC tuning for low latency applications

This assumes that you have read the basics on Java GC at Java Garbage Collection interview Q&A to ascertain your depth of Java knowledge. This is a must know topic for …


03: Understanding Big O notations

Q. Have you seen job advertisements requiring Java candidates to work in real-time or high volume transaction processing systems? If you are applying for such jobs, you can be quizzed on Big O notation. Here …


04: Identifying and fixing LazyInitializationException in Hibernate

Hibernate Lazy InitializationException

LazyInitializationException is thrown when an object becomes detached, and if you try to access associated (i.e. proxied) object(s) of a detached object.

Q. What is a detached object in Hibernate?

When …


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800+ Java Interview Q&As

250+ Java Interview FAQs 🔥
FAQs - Prepared?
FAQs - Ice Breaker
FAQs - Core Java
FAQs - JEE
FAQs - Web Services
FAQs - AWS
FAQs - Microservices
FAQs - Architecture
FAQs - Hibernate
FAQs - Spring
FAQs - Key Areas
FAQs - OOP & FP
FAQs - Code Quality
FAQs - UML
FAQs - SQL
FAQs - RDBMS
FAQs - Maven
FAQs - JSON & XML
FAQs - Unix
FAQs - Regex
FAQs - DevOps
FAQs - JMeter
FAQs - GIT
16+ Tech Key Areas Q&As 🔑
Key Area - Going places 🚄
Key Area - Concurrency Mgmt
Key Area - Low Latency
Key Area - Best Practices
Key Area - CI/CD & DevOps
Key Area - Debugging
Key Area - Debug Hibernate
Key Area - Debug Java
Key Area - Debug JEE
Key Area - Debug Spark
Key Area - Debug Spring
Key Area - Design Concepts
Key Area - Design Patterns
Key Area - GoF Design
Key Area - JEE Design
Key Area - Exception Handling
Key Area - Memory Mgmt
Key Area - Performance
Key Area - Scalability
Key Area - SDLC
Key Area - Security
Key Area - Productivity Tools
Key Area - Transaction Mgmt
Key Area - QoS & SLAs
Key Area - Judging Experience
300+ Core Java Interview Q&As
Core Java - Overview
Core Java - Data types
Core Java - Constructors
Core Java - Reserved Key Words
Core Java - Classes
Core Java - Objects
Core Java - OOP
Core Java - GC
Core Java - Generics
Core Java - FP
Core Java - OOP to FP
Core Java - I/O
Core Java - Multithreading
Core Java - Data Structures
Core Java - Annotations
Core Java - AOP
Core Java - Other
Core Java - Collection API
Core Java - Differences X & Y
Core Java - Event Driven
Core Java - Exceptions
Core Java - Java 7
Core Java - Java 8
Core Java - JVM
Core Java - Reactive Program
Core Java - Swing & AWT
Core Java - Understanding
300+ JEE Interview Q&As
JEE - Overview
JEE - Web basics
JEE - Web Services
JEE - JPA
JEE - JTA
JEE - API Design
JEE - JDBC
JEE - Microservices
JEE - JMS
JEE - JMX
JEE - JNDI and LDAP
JEE - JSF
JEE - Other
80+ Spring & Hibernate Q&As
Frameworks - Hibernate Q&As
Frameworks - Spring Core
Frameworks - Spring MVC
Frameworks - Spring Cloud
Frameworks - Spring boot
Frameworks - Spring IO
Frameworks - Spring Config
100+ Architecture FAQs 🔥
Architecture - Patterns
Architecture - How to
Architecture - AWS
Architecture - Distributed
Architecture - Microservices
Architecture - QoS
Architecture - ERD
Architecture - ETL
Architecture - Low Latency
Architecture - UML
80+ Companion Technologies
Companion - Angular JS
Companion - Domain Knowledge
Companion - FIX
Companion - Git & SVN
Companion - Groovy
Companion - JavaScript
Companion - JMeter
Companion - Maven
Companion - NoSQL
Companion - Regex
Companion - SQL
Companion - Unix
Companion - JSON
Companion - XML
Companion - XSD
Companion - YAML
40+ Code Quality - Q&As ✍
Code Quality - Automation
Code Quality - Code Coverage
Code Quality - FAQs
Code Quality - Profiling
Code Quality - Performance Test
Code Quality - Unit Testing
Code Quality - BDD
Code Quality – Testing DAOs
Code Quality – JUnit Spring
Code Quality – JUnit Web
Code Quality - Spring TXN
Tutorials Java, JEE, Spring
Tutorials - ⏯ Starting with Java
Tutorials - Diagnosis
Tutorials - Akka
Tutorials - Akka Scala
Tutorials - Akka Java
Tutorials - AWS EC2
Tutorials - CI/CD Jenkins
Tutorials - Core Java
Tutorials - Debugging
Tutorials - Java 8
Tutorials - JSON and Java
Tutorials - Java Beginner
Tutorials - XML and Java
Tutorials - CSV and Java
Tutorials - Docker
Tutorials - JEE
Tutorials - Web & Web Services
Tutorials - REST Client
Tutorials - JSF
Tutorials - JDBC
Tutorials - FIX and Java
Tutorials - JAXB
Tutorials - JMX
Tutorials - JPA
Tutorials - MySQL
Tutorials - Scala
Tutorials - Scala Actors
Tutorials - Spring & Hibernate
Tutorials - Hibernate
Tutorials - Spring Basics
Tutorials - Spring batch
Tutorials - Hibernate & Spring
Tutorials - Spring Boot
Tutorials - Spring IO
Tutorials - Spring ORM
Tutorials - Spring other
Tutorials - Spring OXM
Tutorials - Spring Cloud
Tutorials - Tools
Tutorials - JMeter
Tutorials - Maven
Tutorials - Maven Assembly
Tutorials - Maven Profiles
Tutorials - Productivity Tools
Tutorials - Kubernetes
Tutorials - ⏯ Videos
Tutorials - ⏯ Starting with Java
Tutorials - ⏯ Spring Core
Tutorials - ⏯ Spring MVC
Tutorials - ⏯ JDBC, Hibernate
Tutorials - ⏯ Spring Boot
Tutorials - ⏯ Angular with Spring
Tutorials - ⏯ Q&As
Tutorials - Other
Tutorials - SQL
Tutorials - Drools
Tutorials - POI
Tutorials - DOS
Tutorials - Dozer
Tutorials - ESB
Tutorials - Groovy
Tutorials - Jasper Reports
Tutorials - Logging and auditing
Tutorials - Metrics
Tutorials - Orika Mapping
Tutorials - Pentaho Kettle ETL
Tutorials - Unix
Tutorials - Webspeher MQ
Tutorials - YAML
150+ Coding Q&As ✍
Coding - Can you write code?
Coding - Complete the code
Coding - Converting from A to B
Coding - Designing your classes
Coding - Data Structures
Coding - Arrays
Coding - Big O notation
Coding - Graph Structure
Coding - LinkedList Structure
Coding - Map Structure
Coding - Pointer Algorithms
Coding - Queue Structure
Coding - Searching Algo
Coding - Sorting Algo
Coding - Stack Structure
Coding - Tree structure
Coding - Data Which & Why
Coding - Passing the unit tests
Coding - What is wrong?
Coding - Home Assignments
Coding - Written Test Core Java
Coding - Written Test JEE
Prepare to fast-track & go places
with multi-offers to choose from & increased earning potential. Expand your horizons along the way by taking the road less travelled.
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Learn by categories such as FAQs – Core Java, Key Area – Low Latency, Core Java – Java 8, JEE – Microservices, Big Data – NoSQL, etc. Some posts belong to multiple categories.
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