What array list and linkedlist difference,how hashmap internally working,what is synchronised and it's type,what is difference between abstract and interface,class loading mechanism in Java, you hat is single ton class means and how to create, what is ioc in spring,what is dependency injection and it's type, what is autowired and it's type,what dispatcher servlet and its work, what is spring boot advantages, what is actuator,how database configuration in spring boot,what is type of joins and its work,java 8 features

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Java Developer interview questions covering array list, linkedlist, hashmap, synchronization, abstract vs interface, singleton class, Spring framework, database configuration, and Java 8 features.

ArrayList and LinkedList differ in terms of implementation, performance, and usage
HashMap uses hashing to store and retrieve key-value pairs
Synchronized is used to ensure thread safety and prevent race conditions
Abstract classes cannot be instantiated and can have both abstract and non-abstract methods, while interfaces only have abstract methods
Singleton class is a class that can only be instantiated once and provides a global point of access to it
Inversion of Control (IoC) is a design pattern where the control of object creation and dependency injection is shifted from the application to a framework
Dependency Injection is a technique where the dependencies of an object are injected into it rather than being created by the object itself
@Autowired is a Spring annotation used for automatic dependency injection
DispatcherServlet is the front controller in Spring MVC that receives incoming requests and dispatches them to the appropriate controller
Spring Boot is a framework that simplifies the development of Spring-based applications by providing auto-configuration and embedded servers
Actuator is a Spring Boot module that provides endpoints for monitoring and managing the application
Database configuration in Spring Boot can be done using application.properties or application.yml files
There are four types of joins in SQL: inner join, left join, right join, and full outer join
Java 8 features include lambda expressions, functional interfaces, streams, and default methods

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