UndeclaredThrowableException (Java SE 21 & JDK 21)
Description: declaration: module: java.base, package: java.lang.reflect, class: UndeclaredThrowableException
Keywords: java.lang.reflect.UndeclaredThrowableException class

Module java.base
Package java.lang.reflect

# Class UndeclaredThrowableException

java.lang.Object
java.lang.Throwable
java.lang.Exception
java.lang.RuntimeException
java.lang.reflect.UndeclaredThrowableException

All Implemented Interfaces:
  `Serializable`

public class UndeclaredThrowableException extends RuntimeException
Thrown by a method invocation on a proxy instance if its invocation handler's `invoke` method throws a checked exception (a `Throwable` that is not assignable to `RuntimeException` or `Error`) that is not assignable to any of the exception types declared in the `throws` clause of the method that was invoked on the proxy instance and dispatched to the invocation handler.

An `UndeclaredThrowableException` instance contains the undeclared checked exception that was thrown by the invocation handler, and it can be retrieved with the `getUndeclaredThrowable()` method. `UndeclaredThrowableException` extends `RuntimeException`, so it is an unchecked exception that wraps a checked exception.

Since:
  1.3
See Also:
  - `InvocationHandler`
  - Serialized Form

- ## Constructor Summary

  Constructors
  Constructor
  Description
  `UndeclaredThrowableException(Throwable undeclaredThrowable)`
  Constructs an `UndeclaredThrowableException` with the specified `Throwable`.
  `UndeclaredThrowableException(Throwable undeclaredThrowable, String s)`
  Constructs an `UndeclaredThrowableException` with the specified `Throwable` and a detail message.

- ## Method Summary

  Modifier and Type
  Method
  Description
  `Throwable`
  `getUndeclaredThrowable()`
  Returns the `Throwable` instance wrapped in this `UndeclaredThrowableException`, which may be `null`.

  ### Methods declared in class java.lang.Throwable

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

  ### Methods declared in class java.lang.Object

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

- ## Constructor Details

  - ### UndeclaredThrowableException

    public UndeclaredThrowableException(Throwable undeclaredThrowable)
    Constructs an `UndeclaredThrowableException` with the specified `Throwable`.
    Parameters:
      `undeclaredThrowable` - the undeclared checked exception that was thrown

  - ### UndeclaredThrowableException

    public UndeclaredThrowableException(Throwable undeclaredThrowable, String s)
    Constructs an `UndeclaredThrowableException` with the specified `Throwable` and a detail message.
    Parameters:
      `undeclaredThrowable` - the undeclared checked exception that was thrown
      `s` - the detail message

- ## Method Details

  - ### getUndeclaredThrowable

    public Throwable getUndeclaredThrowable()
    Returns the `Throwable` instance wrapped in this `UndeclaredThrowableException`, which may be `null`.
    API Note:
      This method predates the general-purpose exception chaining facility. The `Throwable.getCause()` method is now the preferred means of obtaining this information.
    Returns:
      the undeclared checked exception that was thrown