Java Tutorial

Java Tutorial Java Features C++ vs Java Java History Java Hello World Java Development Kit Java Runtime Environment Java Virtual Machine Difference between JDK, JRE, and JVM Memory Areas in Java Java Operators Java Keywords Primitive Data Types Variables

Java Loops

Java Do While Loop Java While Loop Java For Loop Java Enhanced For Loop

Java Programs

Java Basic Programs Factorial Program in Java Fibonacci Series Program in Java Prime Number Program in Java Palindrome Number Program in Java Armstrong Number Program in Java Anagram Program in Java Pattern Programs in Java Calculator Program in Java Leap Year Program in Java Addition Program in Java Number Pattern Programs in Java Star Pattern Programs in Java Package Program in Java Pyramid Program in Java Sorting Program in Java String Palindrome Program in Java Even Odd Program in Java For Loop Program in Java If Else Program in Java Switch Case Program in Java GCD Program in Java LCM Program in Java Hello Program in Java Matrix Program in Java Menu Driven Program in Java Series Program in Java Client Server Program in Java Swapping Program in Java Pig Latin Program in Java Tower of Hanoi Program in Java Recursion Program in Java Matrix Multiplication Program in Java Perfect Number Program in Java Classes and Objects in Java Example Programs String Programs in Java Array Programs in Java Constructor Program in Java Inheritance Program in Java Abstract class Program in Java Interface Program in Java Encapsulation Program in Java Polymorphism Program in Java Exception Handling Program in Java Multithreading Program in Java Thread Program in Java Collection Programs in Java ArrayList Program in Java Stack Program in Java Applet Program in Java Swing Program in Java JDBC Program in Java How to run Java program in command prompt How to run Java program in Eclipse

Java Sorting

Sorting Algorithms in Java Merge Sort in Java Quick Sort in Java Bubble Sort in Java Insertion Sort in Java Selection Sort in Java Heap Sort in Java Radix Sort in Java Topological Sort in Java Bucket Sort in Java Counting Sort in Java

Java OOPs Concepts

OOPs - Object Oriented Programming Objects and Classes in Java Java Naming Conventions Constructors in Java Java this keyword Java static keyword Inheritance in Java Aggregation in Java Java super keyword Constructor Chaining and Constructor Overloading Java Polymorphism Static and Dynamic Binding in Java Java Abstraction Abstract class in Java Interface in Java Difference between Abstract class and Interface Java final keyword Packages in Java Access Modifiers in Java Java Wrapper classes Java Numbers Java Characters Java Integer Java Boolean Java Arrays Java Command Line Arguments Java strictfp Keyword Java Math

Java Strings

Java Strings Java String Methods StringBuilder in Java StringBuffer in Java Java Regular Expressions StringBuffer vs StringBuilder String vs StringBuffer String vs StringBuilder String Manipulation in Java Java String Concatenation How to Reverse a String in Java String Array in Java How to Compare Two Strings in Java How to Concatenate Two Strings in Java Why String in Immutable in Java java.lang.NumberFormatException for Input String String Pool in Java Java Generate Random String How to take String Input in Java Java String Interview Questions

Java Exceptions

Exception Handling in Java Java try catch Java throw Java throws Difference between throw and throws Java finally Java Custom Exception Java Exception Propagation

Garbage Collection

Automatic Resource Management in Java Java Garbage Collection Java finalize() Java gc() Difference between final, finally and finalize


Multithreading in Java Process and Thread in Java Basic Terms in Multithreading Java Thread creation Thread Scheduler in Java Java Thread class DeadLock in Java

Java IO

Java IO Java Read File Java BufferedWriter Java InputStreamReader Java File Java Read File Line By Line Java FileOutputStream Jar File in Java


Java Serialization Java transient


Java Network Programming Java Socket Programming Java URL Java URLConnection HttpURLConnection in Java Java InetAddress Java DatagramSocket and Java DatagramPacket


Java AWT


Swing in Java

Java Collections

Collections in Java Java List Interface ArrayList in Java LinkedList in Java Vector in Java Stack in Java ArrayList vs LinkedList in Java ArrayList vs Vector in Java Java Set Interface HashSet in Java LinkedHashSet in Java TreeSet in Java Java Queue Interface PriorityQueue in Java ArrayDeque in Java Java Map Interface HashMap in Java LinkedHashMap in Java TreeMap in Java Dictionary in Java Hashtable in Java Properties in Java Collections class in Java Java Comparable Java Comparator Comparable vs Comparator in Java

Java Generics

Generics in Java

Java Annotations

Annotations in Java


Java JDBC Tutorial

Java Differences

Java vs JavaScript Python vs Java Kotlin vs Java Java vs C++ C# vs Java Static vs Non-static in Java C vs Java int vs Integer in Java Stack vs Heap in Java Java Array vs ArrayList

How to

How to run Java program How to set path in Java How to check the Java version in cmd How to install Java in Windows 10 How to run Java program in cmd How to call a method in Java How to sort an array in Java How to iterate HashMap in Java How to write Java program How to create an array in Java How to create a package in Java How to generate random numbers in Java How to input String in Java How to create thread in Java How to find length of String in Java How to sort a string in Java How to use scanner in Java How to achieve multiple inheritance in Java How to run Java program in Eclipse How to call a function in Java How to create array of objects in Java How to create custom exception in Java How to achieve abstraction in Java How to call static method in Java

Java 8 Features

Java 8 Features Lambda Expressions in Java Functional Interface in Java Streams in Java Java Base64 Encoding and Decoding Parallel Arrays Sort in Java

Java 9 Features

Java 9 Tutorial Java 9 Try With Resources Java 9 Interface Private Method

Java Servlet Tutorial

Java Servlets Tutorial

Java JSP Tutorial

Java JSP Tutorial

Hibernate Tutorial

Hibernate Tutorial

Spring Tutorial

Spring Tutorial

Spring MVC Tutorial

Spring MVC Tutorial

Jenkins Tutorial

Jenkins Tutorial

Java Math Methods

Math.abs() Math.acos() Math.addExact() Math.asin() Math.atan () Math.atan2() Math.cbrt() Math.ceil() Math.copysign() Math.cos() Math.cosh() Math.decrementExact() Math.exp() Math.expm1() Math.floor() Math.floorDiv() Math.floorMod() Math.getExponent() Math.hypot() Math.IEEEremainder() Math.incrementExact() Math.log() Math.log10() Math.log1p() Math.max() Math.min() Math.multiplyExact() Math.multiplyFull() Math.negateExact() Math.nextAfter() Math.nextDown() Math.nextUp() Math.pow() Math.random() Math.rint() Math.round() Math.scalb() Math.signum() Math.sin() Math.sinh() Math.sqrt() Math.subtractExact() Math.tan() Math.tanh() Math.toDegrees() Math.toIntExact() Math.toRadians() Math.ulp()

Java String Methods

toCharArray() copyValueOf() endsWith() equals() equalsIgnoreCase() format() getBytes() getChars() hashCode() indexOf() intern() isEmpty() join() lastIndexOf() length() replace() replaceAll() replaceFirst() split() startsWith() subSequence() substring() toLowerCase() toUpperCase() trim() valueOf()

Java Conversion

Java Convert String to int Java Convert int to String Java Convert String to long Java Convert long to String Java Convert String to float Java Convert float to String Java Convert String to double Java Convert double to String Java Convert String to Date Java Convert Date to String Java Convert String to Object Java Convert Object to String Java Convert String to char Java Convert char to String Java Convert int to long Java Convert long to int


Functional Interfaces in Java Singleton class in Java Awesome explanation of Strings in Java Object class in Java Static class in Java All the important string methods in Java String Handling Method in Java What are Array strings in Java Advantages and Disadvantages of Strings in Java Big Decimal class in Java Class definition in Java Char and String differences in Java Difference between String, StringBuffer and StringBuilder in java Replace character in string Java String Coding Interview Questions in Java What is String in Java? String isnullorempty in Java String Matches in Java Trim Method in String Java Bean class in Java Libraries in Java Arithmetic Operations on String in Java

Java Keywords

The Java Keywords

There are 50 unique keywords defined in the Java language that are used for some internal process or represent some predefined actions.

abstract continue for new switch
assert default goto package synchronized
boolean do if private this
break double implements protected throw
byte else import public throws
case enum instanceof return transient
catch extends int short try
char final interface static void
class finally long strictfp volatile
const float native super while

These keywords in java are uniquely defined, and these are case sensitive. Keywords cannot be used as an identifier, such as they cannot be used as names for a variable, class, or method.

Some keywords were reserved in java, such as true, false, null, const, and goto. We may not use these keywords for the name of variables, classes, and so on.

Keywords are explained below:

Keywords Description
abstract It is used to declare an abstract class that provides the implementation of the interface.
boolean It is used to declare a variable as a boolean type. It only holds true and false values.
break It breaks the current flow of the code (loop or switch statement).
byte This keyword declares a variable that can hold 8-bit data values.
case It is used with the switch statement to define different cases.
catch This keyword is used to catch the exceptions generated by try statements.
char It declares a variable that can hold unsigned 16-bit Unicode characters
class It is used to declare a class.
continue This keyword is used to continue the loop (current flow of the program and skips the remaining code at the specified condition).
default The default keyword is used to define the default block of code in a switch statement.
do This keyword is used in the control statement to declare a loop.
double This keyword declares a variable that can hold a 64-bit floating-point number.
else It is used to indicate the alternative branches in an “if” statement.
enum This keyword defines a fixed set of constants. This constructor is always private or default.
extends It indicates that a class is derived from another class or interface.
final It is used to indicate that a variable holds a constant value. The value of the variable always remains constant if we declare it with the final keyword.
finally It indicates a block of code in a try-catch structure. It is always executed whether an exception is handled or not.
float This keyword declares a variable that can hold a 32-bit floating-point number.
for It executes a set of instructions or functions repeatedly when some conditions become true. If the number of iteration is fixed, it is recommended to use “for loop”.
if It tests the condition and executes the “if block” if the condition is true.
implements It is used to implement an interface.
import This keyword makes classes and interfaces available and accessible to the current source code.
instanceof It tests whether the object is an instance of the specified class or implements an interface.
int It is used to declare a variable that can hold a 32-bit signed integer.
interface It declares an interface. It can have only abstract methods.
long It declares a variable that holds a 64-bit integer.
native This keyword specifies that a method is implemented in native code using JNI (Java Native Interface).
new It creates a new object.
null This keyword indicates that a reference does not refer to anything. It removes the garbage value.
package It declares a Java package that includes the classes.
private It is an access modifier that indicates that a method or variable may be accessed only in the class where it was declared.
protected It is an access modifier that can be accessed within the package and outside the package but through inheritance only. It can't be applied to the class.
public It is an access modifier that is used to indicate that an item can be accessed anywhere. It has the widest scope among all other modifiers.
return This keyword is used to return from a method when its execution is complete.
short This keyword declares a variable that can hold a 16-bit integer.
static This keyword indicates that a variable or method is a class method. It is used for memory management mainly.
strictfp It is used to restrict the floating-point calculations to ensure the portability of the code.
super This keyword is a reference variable that is used to refer to the parent class object. It can also be used to invoke an immediate parent class method.
switch It contains a switch statement which executes code based on test value. It tests the equality of a variable against multiple values.
synchronized This keyword is used to specify the critical sections or methods in a multithreaded code.
this It refers to the current object in a method or constructor.
throw It explicitly throws an exception. The “throw” keyword is used to throw a custom exception, followed by an instance.
throws It declares an exception. A checked exception can be piped with throws.
transient This keyword is used in serialization. If we define any data member as transient, then it can’t be serialized.
try It starts a block of code that will be tested for exceptions. It must be followed by either catch or finally block.
void The void keyword specifies that a method does not have a return value.
volatile This keyword is used to indicate that a variable may change asynchronously.
while It starts a loop that iterates a part of the program number of times.