Java Built-in Exception Classes
In Java, the root class for exception hierarchy is Throwable
, which is divided into two subclasses: Error
and Exception
.
Exception
is divided into RuntimeException
(runtime exceptions) and non-runtime exceptions.
Runtime Exceptions (subclasses of RuntimeException
)
Exception Class | Description |
---|---|
ArithmeticException | Thrown when an exceptional arithmetic condition occurs, such as division by zero. |
NullPointerException | Thrown when attempting to access a member of or call a method on a null object. |
ArrayIndexOutOfBoundsException | Thrown when trying to access an array element with an illegal index. |
IndexOutOfBoundsException | Thrown to indicate that an index is out of range; parent class of ArrayIndexOutOfBoundsException . |
NumberFormatException | Thrown when attempting to convert a string to a number of invalid format. |
IllegalArgumentException | Thrown when a method receives an argument that is not appropriate. |
ClassCastException | Thrown when attempting to cast an object to a subclass it is not an instance of. |
NoSuchElementException | Thrown when attempting to access an element that does not exist. |
Non-runtime Exceptions
Exception Class | Description |
---|---|
IOException | Thrown during general input/output operations. |
FileNotFoundException | Thrown when an attempt to open a file denoted by a specified pathname has failed. |
EOFException | Thrown when the end of a file or stream is unexpectedly reached. |
ClassNotFoundException | Thrown when an application tries to load a class through its string name but no definition for the class with the specified name could be found. |
NoSuchMethodException | Thrown when a particular method cannot be found. |
InterruptedException | Thrown when a thread is waiting, sleeping, or otherwise occupied, and the thread is interrupted. |
SQLException | Thrown during database operations; commonly associated with Java’s database connectivity. |
SecurityException | Thrown by the security manager to indicate a security violation. |
IllegalStateException | Thrown to indicate that a method has been invoked at an illegal or inappropriate time. |
These are some common built-in exception classes. Java provides many other exception classes, each representing a specific type of exceptional condition.
When writing Java programs, you can use try-catch
blocks to catch and handle these exceptions.