What do you understand by collections framework in Java programming language?
A collection is an object that groups or stores multiple objects of similar types. The objects that are stored in the collection are also called as elements of the collection.
Collections framework in Java programming language consists of the following.
1. Interfaces that represent different types of collections. 2. Concrete implementations of the collection interfaces. 3. Algorithmic implementations that perform useful computations, sorting, searching etc. on objects implementing the collection interfaces.
What are the key steps in reading writing to sockets?
1. Open a socket 2. Open an input stream and output stream to a socket
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What is the difference between RecursiveTask and RecursiveAction?
RecursiveTask’s compute() method returns a value, whereas RecursiveAction’s compute() method returns void…
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How many parameters can a lambda expression have?
A lambda expression can have zero, one or multiple parameters.
How do you sort an array of objects using the java.util.Arrays class?
The java.util.Arrays utility class provides the sort() method that sorts an array of objects in ascending order, according to the natural ordering of its elements.
Implemenation Algorithm – The sort() method for sorting arrays containing objects uses Mergesort algorithm instead of the Quicksort algorithm used for sorting arrays containg primitive data types.
Time Complexity – O(N log(N))
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Java programming language provides numerous kinds of data structures and packages them within the Collections API. Java collections interview questions are very frequently asked both in telephonic screening interviews as well as in face-to-face interviews.
Following are some frequently asked questions in Java – Collections
What are Java class loaders? What are the key features of Java class loader
Java class loaders are components in JVM that load Java class file at runtime, when they are referenced for the first time. Each class loader has its own specific namespace, in which it stores the classes that it loads.
Following are the key characteristics of Java class loaders
Hierarchy – Java class loaders in JVM are hierarchal with a parent-child relationship. Bootstrap class loader is the parent of all class loaders.
Delegation model – Before a class loader loads a class, it checks if its parent class loader has already loaded that class. If the parent class loader has loaded that class, then that class is used. If the parent class loader has not loaded the class, then the child class loader loads the class and uses it.
Visibility – …
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What are the benefits and dis-advantages of garbage collector?
Benefits:
Dis-advantages:
During garbage collection process, the JVM may stop all the application process threads from execution. This freezing of application processes is termed as Stop The World