UnknownError (Java Platform SE 8 )
Keywords: java.lang.UnknownError class
Date: 2026-04-17

compact1, compact2, compact3
java.lang

## Class UnknownError

- java.lang.Object
- - java.lang.Throwable
  - - java.lang.Error
    - - java.lang.VirtualMachineError
      - - java.lang.UnknownError

- All Implemented Interfaces:
    Serializable

      public class UnknownError
      extends VirtualMachineError

  Thrown when an unknown but serious exception has occurred in the Java Virtual Machine.
  Since:
    JDK1.0
  See Also:
    Serialized Form

- - ### Constructor Summary

    Constructors
    Constructor and Description
    `UnknownError()` Constructs an `UnknownError` with no detail message.
    `UnknownError(String s)` Constructs an `UnknownError` with the specified detail message.

  - ### Method Summary

    - ### Methods inherited from class java.lang.Throwable

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

    - ### Methods inherited from class java.lang.Object

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

- - ### Constructor Detail

    - #### UnknownError

          public UnknownError()

      Constructs an `UnknownError` with no detail message.

    - #### UnknownError

          public UnknownError(String s)

      Constructs an `UnknownError` with the specified detail message.
      Parameters:
        `s` - the detail message.

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