Class HeadlessException

java.awt.HeadlessException

All Implemented Interfaces:: Serializable

public class HeadlessException extends UnsupportedOperationException

Thrown when code that is dependent on a keyboard, display, or mouse is called in an environment that does not support a keyboard, display, or mouse. Any code that depends on any of those devices should firstly ensure their availability using the GraphicsEnvironment.isHeadless() method and throw HeadlessException if the latter returns true.

Since:

1.4

See Also:

Constructor Summary

Constructor	Description
`HeadlessException()`	Constructs a new `HeadlessException` with `null` as its detail message.
`HeadlessException(String msg)`	Create a new instance with the specified detailed error message.

Method Summary

Modifier and Type	Method	Description
`String`	`getMessage()`	Returns the detail message string of this `HeadlessException`.

Methods declared in class Throwable

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

Methods declared in class Object

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

Constructor Details

HeadlessException

public HeadlessException()

Constructs a new HeadlessException with null as its detail message. The default headless message may replace null in some cases, as outlined below.

For such HeadlessException the default headless error message may be auto-generated for some platforms. The text of the default headless message may depend on whether the GraphicsEnvironment is in fact headless. That is, the default headless message is both system and environmentally dependent.

HeadlessException

public HeadlessException(String msg)

Create a new instance with the specified detailed error message. For some platforms the default headless error message may be added at the end of the specified message. The text of the default headless message may depend on whether the GraphicsEnvironment is in fact headless. That is, the default headless message is both system and environmentally dependent.

Parameters:: msg - the error message

Method Details

getMessage

public String getMessage()

Returns the detail message string of this HeadlessException. Depending on the platform the message specified in the constructor may be followed by the default headless error message. The text of the default headless message may depend on whether the GraphicsEnvironment is in fact headless. That is, the default headless message is both system and environmentally dependent.

Overrides:: getMessage in class Throwable
Returns:: the detail message string of this HeadlessException instance (which may be null).

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https://docs.oracle.com/en/java/javase/25/docs/api/java.desktop/java/awt/HeadlessException.html