Introduction Generally, a fresher learning a programming language like C-lang, thinks that when his program is compiled, the output is guaranteed. With a bit of more practice, he comes to know that there may be problems raised by the system that prevents the program execution. These problems raised at runtime by the system (in Java, …
Introduction Generally, a fresher learning a programming language like C-lang, thinks that when his program is compiled, the output is guaranteed. With a bit of more practice, he comes to know that there may be problems raised by the system that prevents the program execution. These problems raised at runtime by the system (in Java, …
NullPointerException is an unchecked exception from java.lang package. As the name indicates, if an object points to null and further used in the code, the JVM throws NullPointerException. Following is the class signature public class NullPointerException extends RuntimeException Following is the hierarchy Object –> Throwable –> Exception –> RuntimeException –> NullPointerException NullPointerException can be thrown …
Java NoSuchElementException Java NoSuchElementException is raised when the element called does not exist in DS. It is an unchecked exception from java.util package. Following is the hierarchy. Object –> Throwable –> Exception –> RuntimeException –> NoSuchElementException Program on Java NoSuchElementException import java.util.Vector; public class NSE { public static void main(String args[]) { Vector vect = …
As the name indicates, this exception is thrown when the programmer is doing an operation that is illegal at the present moment (but legal at some other time or context). That is, in appropriate time a method is called, the JVM throws this exception. Examples for IllegalStateException are many in Java. Let us explain with …
As the name indicates, this exception is thrown when two objects are modifying a DS (like Vector or ArrayList) concurrently (at the same time when an operation, like iteration, is going on). Observe, the following code. import java.util.*; public class IteratorDemo { public static void main(String args[]) { ArrayList al1 = new ArrayList (); al1.add(“Raju”); …
This is an unchecked exception and as the name indicates, is thrown by the Java runtime environment, when the programmer is trying to modify the state of the thread when it is illegal. It is also of commonsense, there is no meaning of starting a thread which is already started. If the programmer tries to …
This is an unchecked exception as it is a subclass of RuntimeException. We know in exception handling, all the subclasses of RuntimeException are known as unchecked exceptions. Following is the hierarchy. Object –> Throwable –> Exception –> RuntimeException –> ClassCastException Complete exception hierarchy is available at Hierarchy of Exceptions – Checked/Unchecked Exceptions. As the name …
It is an unchecked exception derived from Exception. It comprises of a big bunch of subclasses and these all are known as unchecked exceptions like ArrayIndexOutOfBoundsException, ArithmeticException, NumberFormatException, ClassCastException etc. Following is the hierarchy. Object –> Throwable –> Exception –> RuntimeException Complete exception hierarchy is available at Hierarchy of Exceptions – Checked/Unchecked Exceptions. As it …
MalformedURLException Java Summary: By the end you reach this tutorial you will understand the possibility of throwing MalformedURLException Java. The JDK 1.5 includes twelve exceptions used with network programming. The commonly occurring are MalformedURLException and UnknownHostException. Let us when they are thrown in coding. MalformedURLException is a checked exception. It is inherited from IOException. MalformedURLException …
Java UnknownHostException It is a subclass of IOException. This exception is thrown when the IP address of the other system (say, server) is not found by the networking software. No confusion here, between MalformedURLException and UnknownHostException. Wrong format is MalformedURLException and unable to locate in the network it is UnknownHostException. Following is the hierarchy. Object …
IllegalArgumentException It is an unchecked exception a subclass of RuntimeException. It is thrown by Color constructor when wrong parameters are passed. Observe the syntax of java.awt.Color constructor. Color clr1 = new Color(int red, int green, int blue); The RGB values should be within the range of 0 to 255 (inclusive of both). If other values …
It is a checked exception, generally we experience, when we try to execute a class without main() method. Following is the hierarchy of NoSuchMethodError. Object –> Throwable –> Error –> LinkageError –> IncompatibleClassChangeError –> NoSuchMethodError Full hierarchy of exceptions is available at "Hierarchy of Exceptions – Checked/Unchecked Exceptions". Following program illustrates. public class Demo { …
ClassNotFoundException is a checked exception from java.lang package, you get generally when you load a class manually with forName() method of class Class. This you experience in JDBC (Java Database Connectivity) where you load the driver from hard disk. Observe the following snippet of code. Class.forName(“sun.jdbc.odbc.JdbcOdbcDriver”); In the above statement, forName() method of class Class …
NumberFormatException is an unchecked exception thrown by parseXXX() methods when they are unable to format (convert) a string into a number. Sometimes, in Java coding, we get input (like from command-line arguments and text field) from the user in the form of string. To use the string in arithmetic operations, it must be converted (parsed) …
Certain methods cannot be executed by the JVM alone. JVM takes the help of the underlying operating system to do the job. Such methods are known as native methods. For example, for all the file operations and thread operations, the JVM should communicate with the operating system and with the operating system cooperation, the task …
A few methods in Java API cannot be executed by the JVM alone. JVM takes the help of the underlying operating system to do the job. Such methods are known as native methods. For example, for all the file operations and thread operations, the JVM should communicate with the operating system (where the Java program …
IndexOutOfBoundsException Summary: In this tutorial, you learn handling of IndexOutOfBoundsException with its subclasses. IndexOutOfBoundsException is an unchecked exception that extends RuntimeException. This is used by the JVM to check the index number entered by the user is within the range of an array or string. Full hierarchy of exceptions is available at "Hierarchy of Exceptions …
