uka.transport
Class TransportDescriptor

java.lang.Object
  uka.transport.TransportDescriptor

All Implemented Interfaces:

TransportConstants

public abstract class TransportDescriptor

extends java.lang.Object

implements TransportConstants

A transport descriptor either provides access to an object's mashaling and unmarshaling routines, or implements marshaling outside the object's class. The second case is useful, when marshaling functionality should be provided for library classes.

Each transportable class requires an associated TransportDescriptor.

Associating a TransportDescriptor with a class can be done in two ways:

• Either the class must declare a public static variable of type TransportDescriptor named TRANSPORT_DESCRIPTOR.
• For library classes that are not available in source code, a transport descriptor can be placed in a sub-package of uka.transport.descriptors. The sub-package must correspond to the full package of the class. The name of the transport descriptor class must be the name of the original class with the postfix "Adapter" appended.

The default way to declare a class transportable is to implement the Transportable interface and a special constructor with the same signature as the method {#unmarshalReference}. The corresponding transport descriptor can then simply forward calls to the appropriate methods of the object.

Note: The JavaParty compiler does automatically make classes transportable. When compiling your source files with JavaParty, it should not be necessary to deal with transport related methods and interfaces.

For fast local deep cloning, the class must provide an implementation of the deepClone(java.lang.Object, int, uka.transport.DeepClone) method. See DeepClone for details.

Author:

Bernhard Haumacher

Field Summary

Fields inherited from interface uka.transport.TransportConstants

REQUEST_MAX, REQUEST_MAX_boolean, REQUEST_MAX_byte, REQUEST_MAX_char, REQUEST_MAX_double, REQUEST_MAX_float, REQUEST_MAX_int, REQUEST_MAX_long, REQUEST_MAX_short, SIZEOF_boolean, SIZEOF_byte, SIZEOF_char, SIZEOF_double, SIZEOF_float, SIZEOF_int, SIZEOF_long, SIZEOF_short, TC_ANONYMOUS, TC_DEFAULT, TC_EXCEPTION, TC_NEW, TC_NULL, TC_REFERENCE, TC_REPLACEMENT, TC_RESET, TC_RESETTYPE, TC_TYPE, TC_USER

Constructor Summary

TransportDescriptor()

Method Summary

abstract java.lang.Object	deepClone(java.lang.Object obj, int id, DeepClone helper) Creates a deep clone of the given object.
boolean	deepCloneReferences(java.lang.Object orig, java.lang.Object copy, DeepClone helper)
abstract java.lang.Class	getType() Return the class, this transport descriptor is associated with.
void	marshal(java.lang.Object obj, MarshalStream s) Marshals all non-final fields of the given object to the stream.
void	marshalReference(java.lang.Object obj, MarshalStream s) Marshals all final fields of the given object to the stream.
void	restoreAfterUnmarshal(java.lang.Object obj)
boolean	unmarshal(java.lang.Object obj, UnmarshalStream s) Unmarshals all non-final fields of the given object.
abstract java.lang.Object	unmarshalReference(UnmarshalStream s, int id) Calls the unmarshaling constructor of the associated class and returns the newly created object.

Methods inherited from class java.lang.Object

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

Constructor Detail

TransportDescriptor

public TransportDescriptor()

Method Detail

unmarshalReference

public abstract java.lang.Object unmarshalReference(UnmarshalStream s,
                                                    int id)
                                             throws java.lang.ClassNotFoundException,
                                                    java.io.IOException

Calls the unmarshaling constructor of the associated class and returns the newly created object. The unmarshaling constructor must UnmarshalStream.register(java.lang.Object, int) the created object with the stream under the given id, and read all final fields from the stream.

Throws:

java.lang.ClassNotFoundException

java.io.IOException

unmarshal

public boolean unmarshal(java.lang.Object obj,
                         UnmarshalStream s)
                  throws java.lang.ClassNotFoundException,
                         java.io.IOException

Unmarshals all non-final fields of the given object. This method is called during the unmarshaling process, after the object is constructed in the unmarshalReference(uka.transport.UnmarshalStream, int) method.

Throws:

java.lang.ClassNotFoundException

java.io.IOException

See Also:

Transportable.unmarshal(uka.transport.UnmarshalStream)

marshalReference

public void marshalReference(java.lang.Object obj,
                             MarshalStream s)
                      throws java.io.IOException

Marshals all final fields of the given object to the stream.

Throws:

java.io.IOException

See Also:

Transportable.marshalReference(uka.transport.MarshalStream)

marshal

public void marshal(java.lang.Object obj,
                    MarshalStream s)
             throws java.io.IOException

Marshals all non-final fields of the given object to the stream.

Throws:

java.io.IOException

See Also:

Transportable.marshal(uka.transport.MarshalStream)

deepClone

public abstract java.lang.Object deepClone(java.lang.Object obj,
                                           int id,
                                           DeepClone helper)
                                    throws java.lang.CloneNotSupportedException

Creates a deep clone of the given object. The given helper object is used to resolve references to already cloned objects in a graph. The result must be identical to marshaling the given object and immediately reading it back from a MarshalStream/UnmarshalStream pair.

Throws:

java.lang.CloneNotSupportedException

deepCloneReferences

public boolean deepCloneReferences(java.lang.Object orig,
                                   java.lang.Object copy,
                                   DeepClone helper)
                            throws java.lang.CloneNotSupportedException

Throws:

java.lang.CloneNotSupportedException

restoreAfterUnmarshal

public void restoreAfterUnmarshal(java.lang.Object obj)
                           throws java.lang.ClassNotFoundException,
                                  java.io.IOException

Throws:

java.lang.ClassNotFoundException

java.io.IOException

getType

public abstract java.lang.Class getType()

Return the class, this transport descriptor is associated with.