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## java.io
Class ObjectStreamClass

    java.lang.Object
      |
      +--java.io.ObjectStreamClass

All Implemented Interfaces:
  Serializable

public class ObjectStreamClass
extends Object
implements Serializable

Serialization's descriptor for classes. It contains the name and serialVersionUID of the class.
The ObjectStreamClass for a specific class loaded in this Java VM can be found/created using the lookup method.

The algorithm to compute the SerialVersionUID is described in Object Serialization Specification, Section 4.4, Stream Unique Identifiers.

Since:
  JDK1.1
See Also:
  `ObjectStreamField`, Object Serialization Specification, Section 4, Class Descriptors, Serialized Form

Field Summary
`static ObjectStreamField[]` | `NO_FIELDS` Set serialPersistentFields of a Serializable class to this value to denote that the class has no Serializable fields.

Method Summary
`Class` | `forClass()` Return the class in the local VM that this version is mapped to.
`ObjectStreamField` | `getField(String name)` Get the field of this class by name.
`ObjectStreamField[]` | `getFields()` Return an array of the fields of this serializable class.
`String` | `getName()` The name of the class described by this descriptor.
`long` | `getSerialVersionUID()` Return the serialVersionUID for this class.
`static ObjectStreamClass` | `lookup(Class cl)` Find the descriptor for a class that can be serialized.
`String` | `toString()` Return a string describing this ObjectStreamClass.

Methods inherited from class java.lang.Object
`clone, equals, finalize, getClass, hashCode, notify, notifyAll, wait, wait, wait`

Field Detail

### NO_FIELDS

    public static final ObjectStreamField[] NO_FIELDS

  Set serialPersistentFields of a Serializable class to this value to denote that the class has no Serializable fields.

Method Detail

### lookup

    public static ObjectStreamClass lookup(Class cl)

  Find the descriptor for a class that can be serialized. Creates an ObjectStreamClass instance if one does not exist yet for class. Null is returned if the specified class does not implement java.io.Serializable or java.io.Externalizable.
  Parameters:
    `cl` - class for which to get the descriptor
  Returns:
    the class descriptor for the specified class

### getName

    public String getName()

  The name of the class described by this descriptor.
  Returns:
    a `String` representing the fully qualified name of the class

### getSerialVersionUID

    public long getSerialVersionUID()

  Return the serialVersionUID for this class. The serialVersionUID defines a set of classes all with the same name that have evolved from a common root class and agree to be serialized and deserialized using a common format. NonSerializable classes have a serialVersionUID of 0L.
  Returns:
    the SUID of the class described by this descriptor

### forClass

    public Class forClass()

  Return the class in the local VM that this version is mapped to. Null is returned if there is no corresponding local class.
  Returns:
    the `Class` instance that this descriptor represents

### getFields

    public ObjectStreamField[] getFields()

  Return an array of the fields of this serializable class.
  Returns:
    an array containing an element for each persistent field of this class. Returns an array of length zero if there are no fields.
  Since:
    1.2

### getField

    public ObjectStreamField getField(String name)

  Get the field of this class by name.
  Parameters:
    `name` - the name of the data field to look for
  Returns:
    The ObjectStreamField object of the named field or null if there is no such named field.

### toString

    public String toString()

  Return a string describing this ObjectStreamClass.
  Overrides:
    `toString` in class `Object`
  Following copied from class: `java.lang.Object`
  Returns:
    a string representation of the object.

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