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These java tutorials will help freshers to start there java careers because all the explanations have done considering you are learning topic first time with lots of real time programs and examples.
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YES, for experienced developers it contains extremely detailed explanations and in-depth coverage of topics .

So, it's time for even freshers to become pro developers.


In short all topics are explained in simple, detailed and in-depth analysis of topics so that freshers could start leaning and experienced developers can master themselves in it.
Good luck friends!

I promise you the best way of explaining core java topics. My main focus is to maintain quality of content which I publish.
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Core Java tutorial in detail

>Collection framework Tutorial in java in detail

>Exceptions handling Tutorial in java in detail

>Thread Concurrency Tutorial in java

>Series of JVM and Garbage Collection (GC) in java - Best explanations ever with exclusive summary section

>Serialization And Deserialization Tutorial

>RegEx (Regular expression) tutorial with examples

>iText library tutorial - working with PDF files in java

>Sorting & searching in java - Bubble, selection, insertion, Advanced sorting - Merge and quick sort, Binary Search with recursion

>Data structures in java - Stack, queue, Singly and doubly linkedList

>Custom Implementation of Map, Set and Lists in java - HashMap, LinkedHashMap, HashSet, LinkedHashSet, ArrayList, Vector

>Basic programs for java beginners

>Interview Programs (beginner to advanced) in java

>Core java QUIZ - Mcq(Multiple choice questions)

>Interview Questions and answers in Java - Top and most important - BEST EXPLANATION EVER




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Java tutorial & history of java >

Java tutorial - Advantage, Where is java used in real world, platform independent language


History of java - Team, Initial target, first big success, now a days, 4 platforms, creator, principles, releases of java



Setting JDK path in windows and linux >

Download and install JDK, Setting environment variables JAVA_HOME & JDK PATH temporarily and permanently in windows, What is a path? need to set PATH variable?


JDK path in Linux and Unix temporarily and permanently, What is a path?Why we need to set PATH variable? setting environment variable



First java program using notepad and eclipse >

Writing and executing first java program through CMD in windows, Setting up ECLIPSE in java, Directory of .class file



Classes, objects, interface, abstract classes and constructors in core java tutorial >

Classes and Objects in java - Class consist of blocks, constructor, variables, methods, inner classes and inner interfaces


Interface in java - Multiple inheritance, Marker interfaces, When to use interface practically, 12 features


Abstract class in java - When to use abstract class or interface practically, 10 features


Constructor in java - Constructor chaining, access modifiers with constructors, constructor overloading, exception thrown, constructors are not inherited


10 Differences between Interface and abstract class in java - in detail with programs



Access modifiers in core java >

Access modifier /Access specifier in java - private, package-private(Default), protected and public - Diagram and tabular form



Method overloading and overriding in core java >

Method overloading in java - in detail with programs,10 Features,need of method overloading, overloading main method, Diagram and tabular form of Implicit casting/promotion of primitive Data type


Method overriding in java - in detail with programs, 10 Features, need of method overriding, understanding @Override annotation, Covariant return, diagram to understand access modifiers


10 Difference between Method overloading and Method overriding in java - in detail with programs


Naming conventions in core java tutorial >

Source file naming rule in java - When source file consists of public class & non-public classes OR only non-public classes


Java naming conventions for interface, class, package, variable, reference variable to object, method, constant - using code comments in java



oops principle in core java tutorial >

4 oops (object oriented programming system) concepts in java > Encapsulation, Abstraction, Inheritance, Polymorphism in detail with programs, abstraction interface via Abstract classes, Inheritance via extends and implements,Compile Runtime polymorphism

What is Encapsulation in java - OOPS principles

What is Abstraction in java - OOPS principles

What is Inheritance in java - OOPS principles

What is compile and runtime Polymorphism in java - OOPS principal




4 java platforms in core >

Differences and relation between 4 Java Programming Language Platforms > Java SE/ J2SE - Standard Edition, Java EE/ J2EE - Enterprise Edition, Java ME/ J2ME - Micro Edition, JavaFX



JDK, JRE, JVM in core java >

JDK (Java Development Kit), JRE (Java Runtime environment), JVM (java virtual machine), Differences between JDK, JRE and JVM, OpenJDK, JIT Compiler (Just In Time Compiler) internal working


JVM (java virtual machine)

What is JDK (Java Development Kit)

What is JRE (Java Runtime environment)

What are Differences between JDK, JRE and JVM

What is OpenJDK

What is JIT Compiler (Just In Time Compiler) in JVM





Data types, operators, control flow statements in core java >

Primitive, Custom/reference Data Types, Integer, Floating-Point, Character and String literal, Escape sequence in java, decimal to hexaDecimal and binary conversion program

What are Primitive Data Types in java

What are Custom/reference Data Types in java

What are Literals in java - Integer, Floating-Point, Character and String literal, Escape sequence in java

What is Implicit casting/promotion of primitive Data type with programs in java


Arithmetic, Unary, Equality, Relational, Conditional, Bitwise, Bit Shift, Assignment, instanceof operators in detail with programs.

What are Arithmetic Operators in java

What are Unary Operators in java

What are Equality, Relational, and Conditional Operators in java

What are Bitwise & Bit Shift Operators in java

What are Assignment Operators in java

What are instanceof Operator (used for Type Comparison) in java


Control Flow Statements = Decision making - if, else, switch | Looping - for, Infinite, Enhanced for loop, while, do-while | Branching - break, Labeled break, continue, Labeled continue, return, goTo





What are Blocks in java


Keywords in core java >


final keyword in java - 20 salient features


Static keyword in java - variable, method, class, block - 24 salient features


Why Static method cannot be overridden in java - Explanation with program


What is static import in core java


Super keyword in java - Invoke constructor, Access instance variable, Invoke instance method of immediate super class using super


this keyword in java - in constructor, refer instance variable, call instance method, this (current class object) as a parameter, return this


What is use of strictfp keyword in java

const keyword in java




garbage collection java >

How garbage collection works internally in java | Mark and sweep algorithm


finalize method in java - 13 salient features


Why finalize method is protected in java - An explanation with programs




String and String pool in core java >

String is Immutable in java

String pool/ String literal pool/ String constant pool in java

Difference between constant pool and String pool in core java



Autoboxing and unboxing in core java >






Immutable classes in core java >

Creating Immutable class in java



Cloning in core java tutorial >

Cloning in java using clone- Shallow and deep copy - 8 techniques for deep copying- 8 important points about cloning



Reflection in core java >

Reflection in java - Methods used and program



Covariant return type, Varargs and toString method in core java tutorial>

What is Covariant return type in core java

Varargs method (Variable arguments) in core java

how to use toString method in java



Design patterns in core java tutorial >

Singleton in java, Doubly Locked Singleton class/ Lazy initialization, enum singleton, eager initialization in static block



Few basic terminologies, concepts in core java tutorial>

Difference between arguments and parameters in java


Copy by value and copy by reference in java - Primitive are passed by value & objects by reference


ASCII codes >

ASCII values of characters in java


Few more facts about java >

How many java developers are there in the world



Differences in core java >

10 Differences between Interface and abstract class in java - in detail with programs


10 Difference between Method overloading and Method overriding in java - in detail with programs


Difference between equals method and == operator in java - testing with String and StringBuffer


Difference between String, StringBuffer and StringBuilder in java - In depth coverage


Differences between Instance initialization block and Static initialization block in java - Features in detail with programs

Difference between constant pool and String pool in core java


Inner classes in core java >

Inner class/ nested class, static nested class, local and anonymous inner class in java  



Top and most important Core java interview question and answers >


Solving few very common and frequently Core java errors >

Solved - Failed to load the JNI shared Library - JDK - eclipse

Resolve Error: Could not find or load main class

error: Class names are only accepted if annotation processing is explicitly requested in java: solution

Resolve error: Class names, 'className', are only accepted if annotation processing is explicitly requested



Few important java programs>

Find out windows version installed in your system using java program and cmd

How to find out the classpath and where all the jar's are loaded from in java

How to find out location from where the main java class you are running is loaded

Find eclipse version in your system

Find out Java version (32 or 64 bit) installed in your system using java program and cmd

Find out JDK version installed in your system using java program

Find out Operating System name using java program

What is classpath environment variable in java, how to configure it from CMD with example program

how to check string contains substring or not using indexOf and contains method in java


Few JVM related basic java programs>

Find out total number of available processors to JVM

Find Total Amount Of Memory In JVM

Find Free Memory Available In Java virtual machine

Find Maximum Memory That JVM can use

How to terminate JVM in java


Additional core java knowledge>

How many methods can be written in core java class or interface








String, Integer, Long, Double, Float, Short and any other wrapper class should be preferred to use a key in HashMap




Top Overriding equals and hashcode method interview question and answers >


For advanced/experienced users >

  1. Overriding equals and hashcode method of Employee class and using it as a key in custom HashMap >


  1. Overriding equals and hashcode method of Employee class and using it as a key in custom LinkedHashMap >


  1. Overriding equals and hashcode method of Employee class and using it as an element in custom HashSet>


  1. Overriding equals and hashcode method of Employee class and using it as an element in custom LinkedHashSet>





Collection framework Tutorial in java in detail with diagrams and programs


Basic Collection tutorial in core java >

Collection tutorial in java


List tutorial in java >

java.utilArrayList tutorial in java


java.util.LinkedList tutorial in java



Set tutorial in java >

java.util.HashSet tutorial in java



EnumSet tutorial in java with program




Map tutorial in java >

HashMap tutorial in java

ConcurrentHashMap tutorial in java - with Segments formation in detail with diagram



IdentityHashMap tutorial in java with program


WeakHashMap tutorial in java


EnumMap tutorial in java with program




Basic Collection tutorial in core java - All properties in tabular form >

Collection tutorial in java - java.util.List, java.util.Set and java.util.Map all properties in tabular form



Collection framework java tutorial : Collection hierarchy in core java >

List hierarchy tutorial in java - Detailed - java.util.ArrayList, java.util.LinkedList, java.util.vector, java.util.concurrent.CopyOnWriteArrayList classes


Set hierarchy tutorial in java - Detailed - java.util.HashSet, java.util.concurrent.CopyOnWriteArraySet, java.util.LinkedHashSet, java.util.TreeSet, java.util.concurrent.ConcurrentSkipListSet, java.util.EnumSet classes


Map hierarchy tutorial in java - Detailed - java.util.HashMap, java.util.Hashtable, java.util.concurrent.ConcurrentHashMap, java.util.LinkedHashMap, java.util.TreeMap, java.util.concurrent.ConcurrentSkipListMap, java.util.IdentityHashMap, java.util.WeakHashMap, java.util.EnumMap classes



ConcurrentModificationException , Fail-fast and Fail-safe >

ConcurrentModificationException, Fail-fast and Fail-safe in detail in java



Collection framework java tutorial : Important Collection - Similarity and Differences in core java >

List Differences tutorial in java >

ArrayList vs LinkedList - Similarity and Differences in java


ArrayList vs Vector - Similarity and Differences in java


List vs Set - Similarity and Differences in java





Map Differences tutorial in java >

Similarity and Differences between HashMap and Hashtable in java


Similarity and Differences between HashMap and ConcurrentHashMap - in java


HashMap vs Hashtable vs LinkedHashMap vs TreeMap - Differences in java


Similarity and Differences between HashMap vs IdentityHashMap - with program in java



Differences between few more important Collection framework classes in java >


Collection vs Collections - Differences between in java



Similarity and Differences between Iterator vs ListIterator - in java


Differences and similarities between Iterator vs Enumeration - in java


Convert Array to list, list to array,
Array to set, Set to array in java>

How to convert ArrayList to HashSet and Set to Array in Java examples

convert Array to Set and Set to array in Java

How to convert Array to List and ArrayList to array in Java




Synchronize ArrayList - collection framework tutorial in java tutorial >


What is default capacity of ArrayList and Vector, and how they are resized in collection framework tutorial in core java >


Collection framework java tutorial : Important Similarity and Differences Collection classes in concurrent and non-concurrent packages in java >

ArrayList vs CopyOnWriteArrayList - Similarity and Differences with program in java


HashSet vs CopyOnWriteArraySet - Similarity and Differences with program in java


TreeSet vs ConcurrentSkipListSet - Similarity and Differences with program in java


TreeMap vs ConcurrentSkipListMap - Similarity and Differences with program in java




Collection framework java tutorial : Sorting Collection by implementing comparator and Comparable, using TreeMap and TreeSet, Collections.sort and Arrays.sort tutorial in java >

Comparable vs Comparator - differences and sorting list by implementing Comparable and Comparator in classes and inner classes in java


Arrays.sort to sort arrays by implementing Comparator and how Comparator of superclass can be used by subclasses in java


Sort Set by using TreeSet and by implementing Comparator and Comparable interface in java


Sort Map by key in Ascending and descending order by implementing Comparator interface and overriding its compare method and using TreeMap in java


Sort Map by value in Ascending and descending order by implementing Comparator interface and overriding its compare method in java








Consequence and advantage of using ArrayList and Vector tutorial in multithreading environment in java >

Consequence of using ArrayList in multithreading environment in java


Advantage of using Vector in multithreading environment in java







Exceptions Tutorial in java in detail with diagrams and programs

Exception definition in java tutorial>

checked, unchecked Exceptions and Error in Exception handling tutorial in core java>


What are checked (compile time exceptions) in java

What are unchecked (Runtime Exceptions) in java




5 Exceptions handling keywords - try, catch, finally, throw and throws in Exception handling tutorial in core java >







Automatic Resource Management and Try-with-resources in java 7 in Exception handling tutorial in core java >




Exception propagation>




Exception chaining /wrapping tutorial >

what is Exception chaining / wrapping in java


Exception stack trace and debugging it in java tutorial >

What is a stack trace in exceptions in java, how to debug exceptions in application




Method overloading on basis of exceptions in Exception handling in core java




12 Exception handling best practices in Exception handling tutorial in core java >

12 Exception handling best practices and guidelines for using exceptions in java



Handling Exception in static block tutorial >

How to handle exception thrown from static block in java? Why throw not allowed in static block in java




Important Exception differences in Exception handling tutorial in core java >


Difference between multiple catch block and multi catch syntax  in Exception handling in core java



Most frequently occurring Exception and Errors in java >

Most common and frequently occurring checked, unchecked Exceptions and Errors in java


Most common and frequently occurring checked (compile time) and Errors in java >


Most common and frequently occurring unchecked (runtime) in java.


Most common and frequently occurring Errors in java >


Few More >


Top Exception interview question and answers in Exception handling tutorial in core java >

EXCEPTIONS - Top 60 interview questions and answers in java for fresher and experienced - detailed explanation with diagrams Set-1 > Q1- Q25


EXCEPTIONS - Top 60 interview questions and answers in java for fresher and experienced - 30 important OUTPUT questions Set-2 > Q26- Q60







Threads basics in threads / Multithreading tutorial in java >

What is thread in java

Thread states/ Thread life cycle in java in detail with diagram, examples and scenarios

Difference between Process and Thread in java



Write your first thread in java >

Implementing Threads in java by implementing Runnable interface and extending Thread class - How to create your first thread in java/ Learn creating more than one thread (Multithreads) in java


Threads implement their own stack in java - demonstration using program/examples and diagram in threads / Multithreading tutorial

Differences between implementing Runnable interface and extending Thread class in threads / Multithreading tutorial in java

Thread behaviour is unpredictable in threads / Multithreading tutorial in java

When threads are not lightweight process in java, in fact they become heavy weight process


run() and Start() methods in threads / Multithreading tutorial in java >

What will happen if we don’t override run method of thread in java?

What will happen if we override start method of thread in java?

Difference between starting thread with run() and start() methods in java

Can we start Thread again in java?

Volatile keyword vs synchronized in threads / Multithreading tutorial in java>

Volatile keyword in java- difference between synchronized and volatile, 10 key points about volatile keyword, why volatile variables are not cached in memory in threads / Multithreading tutorial in java

Differences between synchronized and volatile keyword in detail in java


Race Condition in threads / Multithreading tutorial in java >

Race condition in multithreading and it's solution in java



Consumer Producer problem solution using different techniques in threads/Multithreading tutorial in java >
Solve Consumer Producer problem by using wait() and notify() methods in multithreading tutorial in java

solve Consumer Producer problem by using wait() and notify() methods, where consumer can consume only when production is over in java


How to solve Consumer Producer problem without using wait() and notify() methods, where consumer can consume only when production is over in java



BlockingQueue in threads / Multithreading tutorial in java >

Solve Consumer Producer problem by using BlockingQueue in multithreading in java


Custom implementation of LinkedBlockingQueue class which implements BlockingQueue interface in threads / Multithreading tutorial in java





DeadLock and its detection in threads / Multithreading tutorial in java >

Deadlock in multithreading - program/example to form DeadLock, solving DeadLock, measures to avoid Deadlock in java.


VisualVM - Thread dumps - Generating and analyzing Thread Dumps using VisualVM - step by step detail to setup VisualVM with screenshots in java


JSTACK - Thread dumps - Generating and analyzing Thread Dumps using JSATCK - step by step detail to setup JSTACK with screenshots in java


Reason why suspend() and resume() methods are deprecated and Deadlock prone in threads / Multithreading tutorial in java

destroy() method in java - usage, reason why destroy() method is deprecated and Deadlock prone in threads / Multithreading tutorial in java.




Important Thread methods (salient features, usage with programs/example) in threads / Multithreading tutorial in java>

Sleep() method in threads - 10 key features with programs/example in java


Wait() and notify() methods- Definition, 8 key features, solving consumer producer problem with & without these methods and consequences of not using wait() and notify() methods in java.



Daemon threads - 12 salient features of Daemon Thread in java

2 alternate ways to stop thread, as stop() method is deprecated in java


Join() method - 10 salient features of join in java

Thread isAlive() method in threads / Multithreading tutorial in java

interrupt() method of thread in java


holdsLock(object) method to find whether current thread holds the lock on monitor of specified object in java.

Thread priorities - setPriority() and getPriority() methods in java

Using Suspend and resume method in threads in threads / Multithreading tutorial in java



Methods for Adding ShutdownHook and handling uncaught runtime exception in threads / Multithreading tutorial in java >

Threads addShutdownHook method in java

Handling uncaught runtime exception generated in run method using - setDefaultUncaughtExceptionHandler method in java



Differences between important thread methods in threads / Multithreading tutorial in java >

Difference between Process and Thread in java

Difference between wait() and sleep() method in threads in java

Differences and similarities between yield() and sleep() in threads in java

Difference between notify() and notifyAll() methods, with program in threads / Multithreading tutorial in java

Difference between wait() and wait(long timeout) -What will be Thread states in java


Difference between object Lock and class Lock in threads / Multithreading tutorial in java

Difference between traditional synchronization and Condition interface in java

Difference between starting thread with run() and start() methods in java

Differences between implementing Runnable interface and extending Thread class in threads / Multithreading tutorial in java

Differences between synchronized and volatile keyword in detail in java




Object and class lock in threads / Multithreading tutorial in core java >

Acquiring object lock - synchronization blocks and methods- multiple threads may exist on same object but only one thread of that object can enter synchronized block/method at a time in java.


Acquiring lock on class, 2 Ways to acquire lock on class in java

Difference between object Lock and class Lock in threads / Multithreading tutorial in java




Thread Pool, Thread local, Busy Spin, ThreadGroup  in threads / Multithreading tutorial in java >

Implement own Thread pool in java

Implementing ThreadPool using custom LinkedBlockingQueue

ThreadLocal in multithreading in threads / Multithreading tutorial in java - methods and usage with program/example

Busy Spin - What is busy spin? Consumer Producer problem with busy spin and solution to busy spin in java.

ThreadGroup in java

Demonstrate ThreadGroup's important methods in DETAIL in java



Green threads in threads / Multithreading tutorial in java >

What are Green Threads in java

Difference between Green Threads and non-green/native threads in java





Situation based questions in threads / Multithreading tutorial in core java -

Suppose you have 2 threads (Thread-1 and Thread-2) on same object. Thread-1 is in synchronized method1(), can Thread-2 enter synchronized method2() at same time in java?


Suppose you have 2 threads (Thread-1 and Thread-2) on same object. Thread-1 is in static synchronized method1(), can Thread-2 enter static synchronized method2() at same time in java?


Suppose you have 2 threads (Thread-1 and Thread-2) on same object. Thread-1 is in synchronized method1(), can Thread-2 enter static synchronized method2() at same time in java?


Suppose you have thread and it is in synchronized method and now can thread enter other synchronized method from that method in java?


Suppose you have thread and it is in static synchronized method and now can thread enter other static synchronized method from that method in java?


Suppose you have thread and it is in static synchronized method and now can thread enter other non static synchronized method from that method in java?


Suppose you have thread and it is in synchronized method and now can thread enter other static synchronized method from that method in java?


Suppose you have 2 threads (Thread-1 on object1 and Thread-2 on object2). Thread-1 is in synchronized method1(), can Thread-2 enter synchronized method2() at same time in java?


Suppose you have 2 threads (Thread-1 on object1 and Thread-2 on object2). Thread-1 is in static synchronized method1(), can Thread-2 enter static synchronized method2() at same time in java?




Guidelines to threadsafe code in core java >


More about Threads in threads / Multithreading tutorial in java >

Thread Starvation in java

Constructor in java cannot be synchronized in java


ThreadDeath error - calling stop method on thread throws ThreadDeath error in java



Top Thread Interviews questions in core java thread tutorial>

THREADS - Top 80 interview questions and answers (detailed explanation with programs/examples) Set-1 >  Q1- Q60 in java

THREADS - Top 80 interview questions and answers, important interview OUTPUT questions and answers, Set-2 > Q61- Q80






Thread Concurrency Tutorial

Executor framework in thread concurrency tutorial in java   >

Executor and ExecutorService framework in java




Atomic operations >

Atomic operations in java


AtomicInteger in java

Implementation of custom/own AtomicInteger in thread concurrency tutorial in java


AtomicLong in java

Implementation of custom/own AtomicLong in thread concurrency tutorial in java


AtomicBoolean in java




Semaphore in thread concurrency tutorial in java  >

Semaphore in java

Implementation of custom/own Semaphore in thread concurrency tutorial in java


Semaphore used for implementing Producer Consumer pattern

Custom Semaphore used for implementing Producer Consumer pattern



Lock and Reentrant Locks in thread concurrency tutorial in java  >

Locks and ReEntrantLocks in java

Implementation of custom/own Lock and ReEntrantLock in java


ReentrantLock class provides implementation of Lock’s newCondition() method - description and solving producer consumer program using this method




ReadWriteLock and ReentrantReadWriteLock in thread concurrency tutorial in java  >

ReadWriteLock and ReentrantReadWriteLock in java

Implementation of custom/own ReadWriteLock and ReentrantReadWriteLock in thread concurrency tutorial in java



CountDownLatch in thread concurrency tutorial in java  >

CountDownLatch in java

Implementation of custom/own CountDownLatch in java



CyclicBarrier in thread concurrency tutorial in java  >

CyclicBarrier in java

Implementation of custom/own CyclicBarrier in thread concurrency tutorial in java




Phaser in java  >

Phaser in java




Exchanger in java  >

Exchanger in java



Future and Callable in java  >


Fork/Join framework in thread concurrency tutorial in java  >

Fork/Join Framework - Parallel programming in java




BlockingQueue and LinkedBlockingQueue in java  >

Solve Consumer Producer problem by using BlockingQueue in multithreading

Custom implementation of LinkedBlockingQueue class which implements BlockingQueue interface





Important Similarity and Differences in thread concurrency tutorial in java >

Differences between execute() and submit() method of executor framework

Difference between synchronized and ReentrantLock

Similarity and Difference between CyclicBarrier and CountDownLatch in Java




Top Thread concurrency Interviews in java >





Serialization And Deserialization Tutorial

What is Serialization in java?


Serializing & DeSerializing objects>

Avoid ObjectInputStream.readObject() from throwing EOFException at End Of File in java



Customizing  Serialization process by implementing Serializable and Externalizable/ Difference between them >


Difference between Externalizable and Serialization interface in java



serialVersionUID  >

Constructor call during DeSerialization >



Serializing and DeSerializing Singleton >


Preserving Singleton’s state during DeSerialization >

Serializing and DeSerializing primitive data types >


Serializing class of Collection Api’s >

Static and Transient are not serialized >

Significance of using Static and Transient member variables - Static and Transient are not serialized in java



compatible and incompatible changes in Serialization and deSerialization >

compatible and incompatible changes in Serialization and deSerialization process in java



Deep copy in java using Serialization and Deserialization >

Deep copy in java using Serialization and Deserialization


More about Serialization >



Serialization Interviews >


Customizing  Serialization process by implementing Serializable and Externalizable >

Avoid ObjectInputStream.readObject() from throwing EOFException at End Of File in java  



IMAGE - Storing in and retrieving out from database

JDBC- Insert/Store/save IMAGE in database by using PreparedStatement's setBinaryStream and executeUpdate methods, using BLOB data type - in java


JDBC- Retrieve IMAGE from database by using PreparedStatement's executeQuery, ResultSet's getBlob method - using BLOB data type - in java


FILE - Storing in and retrieving out from database

JDBC- Insert/Store/save FILE in database by using PreparedStatement's executeUpdate and setCharacterStream methods, using CLOB data type - in java


JDBC- Retrieve FILE from database by using PreparedStatement's executeQuery and ResultSet's getClob method, using CLOB data type - in java




RegEx (Regular expression) tutorial with examples in java


Numeric check >

1. how to check string contains numeric value in java using Regex(Regular Expression) program   

2. How to check string contains ONLY numeric value in Java using Regex(Regular Expression) program


Alphabet check >

3. How to check string contains at least one alphabets in Java using Regex(Regular Expression) program

4. How to check string contains ONLY alphabets/letters in Java using Regex(Regular Expression) program



Special character check >

5. How to check string contains special characters in Java using Regex(Regular Expression) program

6. How to check string contains ONLY special characters in Java using Regex(Regular Expression) program



Alpha numeric check >

7. How to check string is alphanumeric or not in Java using Regex(Regular Expression) program




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