IllegalArgumentException

AI-generated Key Takeaways

• IllegalArgumentException signals that a method received an invalid or inappropriate argument.

• It's an unchecked exception, meaning it doesn't need to be explicitly declared in a method's throws clause.

• It extends RuntimeException and has various direct and indirect subclasses for more specific invalid argument scenarios.

• The exception can be constructed with a detailed message, a cause, or both, to provide context about the error.

public class IllegalArgumentException extends RuntimeException

Known Direct Subclasses IllegalChannelGroupException, IllegalCharsetNameException, IllegalFormatException, IllegalSelectorException, IllegalThreadStateException, InvalidParameterException, InvalidPathException, NumberFormatException, PatternSyntaxException, ProviderMismatchException, UnresolvedAddressException, UnsupportedAddressTypeException, UnsupportedCharsetException IllegalChannelGroupException Unchecked exception thrown when an attempt is made to open a channel in a group that was not created by the same provider.  IllegalCharsetNameException Unchecked exception thrown when a string that is not a legal charset name is used as such.  IllegalFormatException Unchecked exception thrown when a format string contains an illegal syntax or a format specifier that is incompatible with the given arguments.  IllegalSelectorException Unchecked exception thrown when an attempt is made to register a channel with a selector that was not created by the provider that created the channel.  IllegalThreadStateException Thrown to indicate that a thread is not in an appropriate state for the requested operation.  InvalidParameterException This exception, designed for use by the JCA/JCE engine classes, is thrown when an invalid parameter is passed to a method.  InvalidPathException Unchecked exception thrown when path string cannot be converted into a Path because the path string contains invalid characters, or the path string is invalid for other file system specific reasons.  NumberFormatException Thrown to indicate that the application has attempted to convert a string to one of the numeric types, but that the string does not have the appropriate format.  PatternSyntaxException Unchecked exception thrown to indicate a syntax error in a regular-expression pattern.  ProviderMismatchException Unchecked exception thrown when an attempt is made to invoke a method on an object created by one file system provider with a parameter created by a different file system provider.  UnresolvedAddressException Unchecked exception thrown when an attempt is made to invoke a network operation upon an unresolved socket address.  UnsupportedAddressTypeException Unchecked exception thrown when an attempt is made to bind or connect to a socket address of a type that is not supported.  UnsupportedCharsetException Unchecked exception thrown when no support is available for a requested charset.

Known Indirect Subclasses DuplicateFormatFlagsException, FormatFlagsConversionMismatchException, IllegalFormatCodePointException, IllegalFormatConversionException, IllegalFormatFlagsException, IllegalFormatPrecisionException, IllegalFormatWidthException, MissingFormatArgumentException, MissingFormatWidthException, UnknownFormatConversionException, UnknownFormatFlagsException DuplicateFormatFlagsException Unchecked exception thrown when duplicate flags are provided in the format specifier.  FormatFlagsConversionMismatchException Unchecked exception thrown when a conversion and flag are incompatible.  IllegalFormatCodePointException Unchecked exception thrown when a character with an invalid Unicode code point as defined by Character.isValidCodePoint(int) is passed to the Formatter.  IllegalFormatConversionException Unchecked exception thrown when the argument corresponding to the format specifier is of an incompatible type.  IllegalFormatFlagsException Unchecked exception thrown when an illegal combination flags is given.  IllegalFormatPrecisionException Unchecked exception thrown when the precision is a negative value other than -1, the conversion does not support a precision, or the value is otherwise unsupported.  IllegalFormatWidthException Unchecked exception thrown when the format width is a negative value other than -1 or is otherwise unsupported.  MissingFormatArgumentException Unchecked exception thrown when there is a format specifier which does not have a corresponding argument or if an argument index refers to an argument that does not exist.  MissingFormatWidthException Unchecked exception thrown when the format width is required.  UnknownFormatConversionException Unchecked exception thrown when an unknown conversion is given.  UnknownFormatFlagsException Unchecked exception thrown when an unknown flag is given.

Thrown to indicate that a method has been passed an illegal or inappropriate argument.

Public Constructor Summary

	IllegalArgumentException() Constructs an IllegalArgumentException with no detail message.
	IllegalArgumentException(String s) Constructs an IllegalArgumentException with the specified detail message.
	IllegalArgumentException(String message, Throwable cause) Constructs a new exception with the specified detail message and cause.
	IllegalArgumentException(Throwable cause) Constructs a new exception with the specified cause and a detail message of (cause==null ? null : cause.toString()) (which typically contains the class and detail message of cause).

Inherited Method Summary

From class java.lang.Throwable

synchronized final void	addSuppressed(Throwable exception) Appends the specified exception to the exceptions that were suppressed in order to deliver this exception.
synchronized Throwable	fillInStackTrace() Fills in the execution stack trace.
synchronized Throwable	getCause() Returns the cause of this throwable or null if the cause is nonexistent or unknown.
String	getLocalizedMessage() Creates a localized description of this throwable.
String	getMessage() Returns the detail message string of this throwable.
StackTraceElement[]	getStackTrace() Provides programmatic access to the stack trace information printed by printStackTrace().
synchronized final Throwable[]	getSuppressed() Returns an array containing all of the exceptions that were suppressed, typically by the try-with-resources statement, in order to deliver this exception.
synchronized Throwable	initCause(Throwable cause) Initializes the cause of this throwable to the specified value.
void	printStackTrace() Prints this throwable and its backtrace to the standard error stream.
void	printStackTrace(PrintWriter s) Prints this throwable and its backtrace to the specified print writer.
void	printStackTrace(PrintStream s) Prints this throwable and its backtrace to the specified print stream.
void	setStackTrace(StackTraceElement[] stackTrace) Sets the stack trace elements that will be returned by getStackTrace() and printed by printStackTrace() and related methods.
String	toString() Returns a short description of this throwable.

From class java.lang.Object

Object	clone() Creates and returns a copy of this Object.
boolean	equals(Object obj) Compares this instance with the specified object and indicates if they are equal.
void	finalize() Invoked when the garbage collector has detected that this instance is no longer reachable.
final Class<?>	getClass() Returns the unique instance of Class that represents this object's class.
int	hashCode() Returns an integer hash code for this object.
final void	notify() Causes a thread which is waiting on this object's monitor (by means of calling one of the wait() methods) to be woken up.
final void	notifyAll() Causes all threads which are waiting on this object's monitor (by means of calling one of the wait() methods) to be woken up.
String	toString() Returns a string containing a concise, human-readable description of this object.
final void	wait(long timeout, int nanos) Causes the calling thread to wait until another thread calls the notify() or notifyAll() method of this object or until the specified timeout expires.
final void	wait(long timeout) Causes the calling thread to wait until another thread calls the notify() or notifyAll() method of this object or until the specified timeout expires.
final void	wait() Causes the calling thread to wait until another thread calls the notify() or notifyAll() method of this object.

Public Constructors

public IllegalArgumentException ()

Constructs an IllegalArgumentException with no detail message.

public IllegalArgumentException (String s)

Constructs an IllegalArgumentException with the specified detail message.

Parameters

s	the detail message.

public IllegalArgumentException (String message, Throwable cause)

Constructs a new exception with the specified detail message and cause.

Note that the detail message associated with cause is not automatically incorporated in this exception's detail message.

Parameters

message	the detail message (which is saved for later retrieval by the Throwable.getMessage() method).
cause	the cause (which is saved for later retrieval by the Throwable.getCause() method). (A null value is permitted, and indicates that the cause is nonexistent or unknown.)

public IllegalArgumentException (Throwable cause)

Constructs a new exception with the specified cause and a detail message of (cause==null ? null : cause.toString()) (which typically contains the class and detail message of cause). This constructor is useful for exceptions that are little more than wrappers for other throwables (for example, PrivilegedActionException).

Parameters

cause	the cause (which is saved for later retrieval by the Throwable.getCause() method). (A null value is permitted, and indicates that the cause is nonexistent or unknown.)