Module java.desktop
Package java.awt

Class 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:
GraphicsEnvironment.isHeadless(), Serialized Form
  • Constructor Details

    • HeadlessException

      public HeadlessException()
      Constructs new HeadlessException with empty message. 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).