Java Tutorial

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Java Loops

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Java Programs

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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 Methods 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 file Reader Java Buffer Reader Java file Writer Java BufferedWriter Java InputStreamReader Scanner in Java Java StringReader Java StringReader Class Java PrintWriter Java File Java Read File Line By Line Java FileInputStream Java FileOutputStream Java Create File Java Delete File Java Open File Java Read File to String Java copy file Java Read JSON file Jar File in Java Java FileNotFoundException


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 JDBC Architecture Types of JDBC Drivers JDBC vs ODBC Java Database Connectivity with MySQL Statements in java Prepared statement in Java Resultset in java Java ResultSetMetaData DatabaseMetaData in Java Callable Statement in Java Transaction Management in java Design of JDBC

Java Differences

Java vs JavaScript Python vs Java Kotlin vs Java Java vs C++ C# vs Java Java float vs double Java vs Scala Static vs Non-static in Java C vs Java int vs Integer in Java Java protected vs private Java vs Dot Net Stack vs Heap in Java Java Array vs ArrayList Java SE vs EE Difference between = = and equals ( ) in java Difference between C, C++, java

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 add double quotes in a string in Java How to convert list to String in Java 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 find the length of an Array 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 import packages in Java How to run applet Program in Java How to take Array Input in Java How to achieve abstraction in Java How to call static method in Java How to compare characters in Java How to compare dates in Java How to create a linked list in Java How to get ASCII value of char in Java How to initialize string array in Java How to Install Java on MAC How to run java program in ubuntu How to find characters with the maximum number of times in a string java How to Set Java_home in Linux How to Split the String in Java with Delimiter How to uninstall the Java in Ubuntu How to Split String by Comma in Java How to remove special characters from String in Java How to remove last character from String in Java

Java 8 Features

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

Java 9 Features

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

Java 16

Java 16

Java 17

What is new in Java 17

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.fma() 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 Convert Char array to string in java Check whether Java is installed or not How to calculate time difference in Java How to stop execution after a certain time in Java Jagged Array in Java Java ArraylistRemove() Time Complexity Java Swing Time Picker Zigzag Array in Java Array and String based questions in Java Array and String with Examples in Java Best Practices to use String Class in Java What is string in Java why it's immutable Java String Java String Inbuilt functions Java String Matches vs Contains Sum of digits in string in java Check the presence of Substring in a String in java Java import packages Interfaces and Classes in Strings in Java Maximum length of string in java Hidden classes in Java Class memory in Java public static void main string args meaning in java Reverse a String in Java String Concatenation in Java Difference between String and Char Array in Java Buffer reader to read string in Java Split String into String Array in Java Reverse a String using Collections in Java Upcasting and Downcasting in Java String Declaration in Java Method Overloading In Java Java Solid Principles Java Architecture Binary Search Java Star Program in Java Java Type Casting Java Pass-by-Reference Java Framework List Java Destructors Java Control Statements Java Byte Code Java Beans Java Identifiers Character Array in Java Java Applications Java Substring Java Session Non-primitive data types in Java Matrix Multiplication in Java JIT in Java Java Tokens Java Externalization Default Virtual Behaviour in C++ vs Java Why we use static in Java Session Tracking in Java Knapsack problem in Java Java Logo Java exception list Java Iterator Java instance variable Frugal number in Java Fork Join in Java Date time API in java Compile time vs Runtime in java Compare time in java AES 256 Encryption in Java Advanced Java skills What is advance Java? User Defined Exception in Java Upcasting in Java Tree Implementation in Java Special Operators in Java Reentrant Lock in Java Perfect Number in Java Java logger Java LinkedList vs ArrayList File Operation in Java Differences between Byte Code and Machine Code Difference between String Tokenizer and split Method in Java Difference between JIT and JVM in Java Constructor Overloading in Java Conditional operator in Java Concurrent Linked Deque in Java with Examples Command Class in Java Java Break Keyword Best Java IDE Association in Java Access specifiers in Java

Java exception list

Java uses exceptions, like the majority of contemporary programming languages, to deal with both errors and "extraordinary events." When an exception arises inside the program, it messes up the regular logic of the instructions and abruptly ends the process.

Luckily, with a little planning and coding, you can frequently handle these exceptions graciously, enabling your code to keep operating and giving you information for identifying the reason for the unexpected outcome.

How the exceptions are handed

A class or function that encounters an exception generates the exception object and passes the data to that same runtime system (JVM).

The call stack is then traversed by the runtime system to ascertain which layer can manage an exception that was raised or thrown. The search starts with the method where exception was created and proceeds step-by-step through all the call stacks until an exception handler is located. It detects a match when the exception's type matches one that the exception handler can handle.

List of java exceptions with examples

Java defines exception kinds that are connected to its different class libraries. Java also gives users the option to create custom exceptions.

Java exception list

The Built-in Exceptions:

The built-in exceptions are the exceptions that exist in Java libraries. These exceptions can be used to explain a few different fault scenarios. The list of significant built-in Java exceptions is shown below.

  1. ArithmeticException: It is thrown whenever an exceptional circumstance occurs during an arithmetic operation.
  2. ArrayIndexOutOfBoundsException: It must be thrown to let the user know that an array was accessed using an improper index. Its index is either greater or equal to the array size, or it is negative.
  3. ClassNotFoundException: The classNotFoundException in Java arises when the JVM (Java Virtual Machine) tries to load a specific class but can't find the desired class in the classpath you gave, as the name implies. Your classpath is broken as a result of this (which is be a very common problem in the Java world). Beginners in Java may find this issue particularly perplexing. It must be caught or thrown to the caller because ClassNotFoundException is indeed a checked exception.
  4. FileNotFoundException: The package also contains the exception class known as FileNotFoundException. The problem arises when we attempt to access a file that isn't installed on the system. It arises at run time rather than compile time, making it a checked exception.
  5. IOException: When performing input or output actions, such as reading a file or accessing a file, an IOException, or input-output exception, may arise. For instance, if we attempt to read a file using the incorrect path, we receive a FileNotFound Exception. Under the heading of the checked Exceptions, the IOExceptions fall. Exceptions that occur during the compilation of a Java programme are those that have been checked. FileNotFoundException, SSLException, and other subclasses of IOException are only a few examples.
  6. InterruptedException: The execution of any thread that is dozing off or waiting for anything can be interrupted by calling the interrupt() method, which displays an InterruptedException message. The interrupt() function of the Thread class can be used to stop a thread that would be dozing off or waiting.
  7. NoSuchFieldException: When the requested field (or variable) is missing from a class, it is thrown.
  8. NoSuchMethodException: When attempting to access a method that cannot be found, it is thrown.
  9. NullPointerException: Referencing the elements of a null objects causes an exception to be triggered. Null is a symbol for nothing.
  10. NumberFormatException: When a method tries to convert a string to a numeric representation but fails, this exception is thrown.
  11. RuntimeException: This shows an exception that happens in real time.
  12. StringIndexOutOfBoundsException: It is thrown by methods of the String class when such a value seems to be either negative or larger than the length of the string.
  13. IllegalArgumentException: When the method cannot be reached by the programme for a specific operation, an exception that would produce an error or error message. The unchecked exception applies to it.

Illustrations of the Built-in Exception

  • Arithmetic exception
// The ArithmeticException in Java application
class ArithmeticException _Sahithi 
    public static void main(String args[])
        try {
            int s = 40, h = 0;
            int r = s/h;  // it cannot be divide by the zero
            System.out.println ("Answer = " + r);
        catch(ArithmeticException e) {
            System.out.println (" it is a number tha cannot be divided by 0 ");


Java exception list
  • NullPointer Exception
// NullPointerException example programme in Java 
class NullPointer_Sahithi
    public static void main(String args[])
        try {
            String  h= null; //the value that is null
        } catch(NullPointerException e) {


Java exception list
  • StringIndexOutOfBound Exception
// An example StringIndexOutOfBoundsException Java programme
class StringIndexOutOfBound_Sahithi
    public static void main(String args[])
        try {
            String h = "The way she is smiling is very attractive "; // length is 42
            char s = h.charAt(44); // here we are accessing the 45th element
        catch(StringIndexOutOfBoundsException e) {

Output :

Java exception list
  • FileNotFound Exception
// Java example programme for the FileNotFoundException exception
 class Sahithi {
    public static void main(String args[])  {
        try {
            // the file which is in the following does not exist
            File file = new File("E://file.txt");
            FileReader sr = new FileReader(file);
        } catch (FileNotFoundException e) {
           System.out.println("No such file exists");


Java exception list
  • IllegalArgumentException: The eligibility of a person to vote is determined by this programme. There won't be any errors thrown if the age is above or equal to 18. An error with an error statement will be generated if the aged is less than 18.

Additionally, "throw new IllegalArgumentException()" can be specified without an error message. In the IllegalArgumentException() function, we may optionally specify Integer.toString(variable name), which will print the name of the argument that does not meet the specified criterion.

/*whatever may be the package// exclude the package name from this text */
class Sahithi {
   public static void print(int a)
          System.out.println("Voting Rights Eligible");
          throw new IllegalArgumentException("Unqualified to Vote");                        
    public static void main(String[] args) {


Exception in thread "main" java.lang.IllegalArgumentException: Unqualified to Vote at Kamal.print(
at Kamal.main(

The user defined exceptions

Java's built-in exceptions may occasionally be unable to adequately explain a particular circumstance. In certain circumstances, the user may also produce what are known as "user-defined Exceptions."

The steps for creating a user-defined exception are as follows.

  • An exception class that is a subclasses of an Exception that class should be created by the user. Given that every exception is a subclass of an Exception that subclass, the user should do the same for his class. This is accomplished as follows:
class OwnException extends Exception
  • It is possible to create a default constructor for the exception class.
  • Another option is to create a constructor with parameters that takes a string.

This can be used to store exception information. We can use this to call the superclass(Exception) constructor and pass the string along.

OwnException(String sr)
  • It is necessary to generate an object that belongs to the user-defined exception class and toss it through the throw clause in order to invoke an exception of that type, as in:
OwnException sr = new OwnException(“details of the exception”);
throw sr;
  • How to construct your own exception class, MyException, as demonstrated in the application below.
  • Three arrays are used to store information about account numbers, client names, and balance amounts.
  • A for-loop is used in the main() method to display the details. At this point, it is checked to see if the balance in any account falls below the required minimum balance.
  • If this is the case, then "Balance amount is less" is displayed and MyException is raised.

Let us have a look at to the following example

// Programming in Java to display a user-defined exception
// When balance is violated, this software throws an exception.
// the below given amount is Rs 20000
class OwnException extends Exception
    //account information is stored
    private static int acc[] = {2002, 2003, 2004, 2005};
    private static String iden[] =
                 {"Hymavathi", "Janardhan", "Swetha", "Archana", "Sahithi"};
    private static double mon[] =
         {20000.00, 22000.00, 3600.0, 899.00, 4100.55};
    // it is the default constructor
    OwnException() {    }
    // it is the parameterized constructor
    OwnException(String sr) { super(sr); }
    // the main() is written here
    public static void main(String[] args)
        try  {
            // display the table's heading
            System.out.println("ACC" + "\t" + "CUST" +
                                           "\t" + "MON");
            // show the exact account details
            for (int k = 0; k < 5 ; k++)
                System.out.println(acc[k] + "\t" + iden[k] +
                                               "\t" + mon[k]);
                // show your own exception in case of balance < 20000
                if (mon[k] < 20000)
                    OwnException sh =
                       New OwnException("Balance falls short of 20000");
                    throw sh;
        } //it is the end of try
        catch (OwnException e) {

Here the runtime error is

OwnException: Balance falls short of 20000

at OwnException.main(


2002    Hymavathi    20000.0
2003    Janardhan    22000.0
2004    Swetha    3600.0
2005    Archana    899.0