IllegalFormatException

public class IllegalFormatException
extends IllegalArgumentException

Known direct 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` 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.

Unchecked exception thrown when a format string contains an illegal syntax or a format specifier that is incompatible with the given arguments. Only explicit subtypes of this exception which correspond to specific errors should be instantiated.

Summary

Inherited methods

From class


        
          java.lang.Throwable

`final void`	`addSuppressed(Throwable exception)` Appends the specified exception to the exceptions that were suppressed in order to deliver this exception.
`Throwable`	`fillInStackTrace()` Fills in the execution stack trace.
`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()`.
`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.
`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)` Indicates whether some other object is "equal to" this one.
`void`	`finalize()` Called by the garbage collector on an object when garbage collection determines that there are no more references to the object.
`final Class<?>`	`getClass()` Returns the runtime class of this `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.
`String`	`toString()` Returns a string representation of the object.
`final void`	`wait(long timeoutMillis, int nanos)` Causes the current thread to wait until it is awakened, typically by being notified or interrupted, or until a certain amount of real time has elapsed.
`final void`	`wait(long timeoutMillis)` Causes the current thread to wait until it is awakened, typically by being notified or interrupted, or until a certain amount of real time has elapsed.
`final void`	`wait()` Causes the current thread to wait until it is awakened, typically by being notified or interrupted.

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Last updated 2026-08-03 UTC.

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java.lang.Object
↳	java.lang.Throwable
	↳	java.lang.Exception
		↳	java.lang.RuntimeException
			↳	java.lang.IllegalArgumentException
				↳	java.util.IllegalFormatException

Sunbelt Computer Software

PL/B Language Development and Support

IllegalFormatException

Summary

Inherited methods