Module java.base
Package java.io

# Class OptionalDataException

java.lang.Object
java.lang.Throwable
java.lang.Exception
java.io.IOException
java.io.ObjectStreamException
java.io.OptionalDataException

All Implemented Interfaces:
  `Serializable`

public class OptionalDataException extends ObjectStreamException
Exception indicating the failure of an object read operation due to unread primitive data, or the end of data belonging to a serialized object in the stream. This exception may be thrown in two cases:

- An attempt was made to read an object when the next element in the stream is primitive data. In this case, the OptionalDataException's length field is set to the number of bytes of primitive data immediately readable from the stream, and the eof field is set to false.
- An attempt was made to read past the end of data consumable by a class-defined readObject or readExternal method. In this case, the OptionalDataException's eof field is set to true, and the length field is set to 0.

Since:
  1.1
See Also:
  - Serialized Form

## Field Summary

Fields
Modifier and Type
Field
Description
`boolean`
`eof`
True if there is no more data in the buffered part of the stream.
`int`
`length`
The number of bytes of primitive data available to be read in the current buffer.

## Method Summary

### 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`

## Field Details

### length

public int length
The number of bytes of primitive data available to be read in the current buffer.

### eof

public boolean eof
True if there is no more data in the buffered part of the stream.