Class NullPointerException

java.lang.Object

java.lang.Throwable

java.lang.Exception

java.lang.RuntimeException

java.lang.NullPointerException

public class NullPointerException
extends RuntimeException

Thrown when an application attempts to use null in a case where an object is required. These include: Calling the instance method of a null object. Accessing or modifying the field of a null object. Taking the length of null as if it were an array. Accessing or modifying the slots of null as if it were an array. Throwing null as if it were a Throwable value. Applications should throw instances of this class to indicate other illegal uses of the null object. Since: JDK1.0, CLDC 1.0

Constructor Summary

Constructors

Constructor	Description
NullPointerException()	Constructs a NullPointerException with no detail message.
NullPointerException(String s)	Constructs a NullPointerException with the specified detail message.

Method Summary

Methods inherited from class Throwable

addSuppressed, getCause, getLocalizedMessage, getMessage, getStackTrace, getSuppressed, initCause, printStackTrace, setStackTrace, toString

Modifier and Type	Method	Description
final void	addSuppressed(Throwable exception)
Throwable	getCause()	Returns the cause of this throwable or null if the cause is nonexistent or unknown.
String	getLocalizedMessage()
String	getMessage()	Returns the error message string of this Throwable object.
StackTraceElement[]	getStackTrace()
final Throwable[]	getSuppressed()
Throwable	initCause(Throwable cause)	Deprecated. DO NOT USE THIS METHOD, its here just to get the compiler working and isn't intended for use
void	printStackTrace()	Prints this Throwable and its backtrace to the standard error stream.
void	setStackTrace(StackTraceElement[] el)
String	toString()	Returns a short description of this Throwable object.

Methods inherited from class Object

clone, equals, getClass, hashCode, notify, notifyAll, wait, wait, wait

Modifier and Type	Method	Description
protected Object	clone()
boolean	equals(Object obj)	Indicates whether some other object is "equal to" this one.
final Class	getClass()	Returns the runtime class of an object.
int	hashCode()	Returns a hash code value for the object.
final void	notify()	Wakes up a single thread that is waiting on this object's monitor.
final void	notifyAll()	Wakes up all threads that are waiting on this object's monitor.
final void	wait()	Causes current thread to wait until another thread invokes the method or the method for this object.
final void	wait(long timeout)	Causes current thread to wait until either another thread invokes the method or the method for this object, or a specified amount of time has elapsed.
final void	wait(long timeout, int nanos)	Causes current thread to wait until another thread invokes the method or the method for this object, or some other thread interrupts the current thread, or a certain amount of real time has elapsed.

Constructor Details

NullPointerException

public NullPointerException()

Constructs a NullPointerException with no detail message.

NullPointerException

public NullPointerException(String s)

Constructs a NullPointerException with the specified detail message. s - the detail message.