Class AssertionError

java.lang.Object

java.lang.Throwable

java.lang.Error

java.lang.AssertionError

All Implemented Interfaces:: Serializable

public class AssertionError extends Error

Thrown to indicate that an assertion has failed.

The seven one-argument public constructors provided by this class ensure that the assertion error returned by the invocation:

    new AssertionError(expression)

has as its detail message the string conversion of expression (as defined in section Â§5.1.11 of The Java Language Specification), regardless of the type of expression.

Since:

1.4

See Also:

Constructor Summary

Constructor	Description
`AssertionError()`	Constructs an AssertionError with no detail message.
`AssertionError(boolean detailMessage)`	Constructs an AssertionError with its detail message derived from the specified `boolean`, which is converted to a string as defined in section Â§5.1.11 of The Java Language Specification.
`AssertionError(char detailMessage)`	Constructs an AssertionError with its detail message derived from the specified `char`, which is converted to a string as defined in section Â§5.1.11 of The Java Language Specification.
`AssertionError(double detailMessage)`	Constructs an AssertionError with its detail message derived from the specified `double`, which is converted to a string as defined in section Â§5.1.11 of The Java Language Specification.
`AssertionError(float detailMessage)`	Constructs an AssertionError with its detail message derived from the specified `float`, which is converted to a string as defined in section Â§5.1.11 of The Java Language Specification.
`AssertionError(int detailMessage)`	Constructs an AssertionError with its detail message derived from the specified `int`, which is converted to a string as defined in section Â§5.1.11 of The Java Language Specification.
`AssertionError(long detailMessage)`	Constructs an AssertionError with its detail message derived from the specified `long`, which is converted to a string as defined in section Â§5.1.11 of The Java Language Specification.
`AssertionError(Object detailMessage)`	Constructs an AssertionError with its detail message derived from the specified object, which is converted to a string as defined in section Â§5.1.11 of The Java Language Specification.
`AssertionError(String message, Throwable cause)`	Constructs a new `AssertionError` with the specified detail message and cause.

Method Summary

Methods declared in class Throwable

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

Modifier and Type	Method	Description
`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 `Throwable.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(PrintStream s)`	Prints this throwable and its backtrace to the specified print stream.
`void`	`printStackTrace(PrintWriter s)`	Prints this throwable and its backtrace to the specified print writer.
`void`	`setStackTrace(StackTraceElement[] stackTrace)`	Sets the stack trace elements that will be returned by `Throwable.getStackTrace()` and printed by `Throwable.printStackTrace()` and related methods.
`String`	`toString()`	Returns a short description of this throwable.

Methods declared in class Object

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

Modifier and Type	Method	Description
`protected Object`	`clone()`	Creates and returns a copy of this object.
`boolean`	`equals(Object obj)`	Indicates whether some other object is "equal to" this one.
`protected void`	`finalize()`	Deprecated, for removal: This API element is subject to removal in a future version. Finalization is deprecated and subject to removal in a future release.
`final Class<?>`	`getClass()`	Returns the runtime class of this `Object`.
`int`	`hashCode()`	Returns a hash code value for this 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 the current thread to wait until it is awakened, typically by being notified or interrupted.
`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(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.

Constructor Details

AssertionError

public AssertionError()

Constructs an AssertionError with no detail message.

AssertionError

public AssertionError(Object detailMessage)

Constructs an AssertionError with its detail message derived from the specified object, which is converted to a string as defined in section Â§5.1.11 of The Java Language Specification.

If the specified object is an instance of Throwable, it becomes the cause of the newly constructed assertion error.

Parameters:

detailMessage - value to be used in constructing detail message

See Also:

AssertionError

public AssertionError(boolean detailMessage)

Constructs an AssertionError with its detail message derived from the specified boolean, which is converted to a string as defined in section Â§5.1.11 of The Java Language Specification.

Parameters:: detailMessage - value to be used in constructing detail message

AssertionError

public AssertionError(char detailMessage)

Constructs an AssertionError with its detail message derived from the specified char, which is converted to a string as defined in section Â§5.1.11 of The Java Language Specification.

Parameters:: detailMessage - value to be used in constructing detail message

AssertionError

public AssertionError(int detailMessage)

Constructs an AssertionError with its detail message derived from the specified int, which is converted to a string as defined in section Â§5.1.11 of The Java Language Specification.

Parameters:: detailMessage - value to be used in constructing detail message

AssertionError

public AssertionError(long detailMessage)

Constructs an AssertionError with its detail message derived from the specified long, which is converted to a string as defined in section Â§5.1.11 of The Java Language Specification.

Parameters:: detailMessage - value to be used in constructing detail message

AssertionError

public AssertionError(float detailMessage)

Constructs an AssertionError with its detail message derived from the specified float, which is converted to a string as defined in section Â§5.1.11 of The Java Language Specification.

Parameters:: detailMessage - value to be used in constructing detail message

AssertionError

public AssertionError(double detailMessage)

Constructs an AssertionError with its detail message derived from the specified double, which is converted to a string as defined in section Â§5.1.11 of The Java Language Specification.

Parameters:: detailMessage - value to be used in constructing detail message

AssertionError

public AssertionError(String message, Throwable cause)

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

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

Parameters:: message - the detail message, may be null; cause - the cause, may be null
Since:: 1.7

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