org.omg.CORBA
Class NVList

java.lang.Object
  |
  +--org.omg.CORBA.NVList
public abstract class NVList
extends Object

A modifiable list containing NamedValue objects.

The class NVList is used as follows:

  • to describe arguments for a Request object in the Dynamic Invocation Interface and the Dynamic Skeleton Interface
  • to describe context values in a Context object

Each NamedValue object consists of the following:

  • a name, which is a String object
  • a value, as an Any object
  • an argument mode flag

An NVList object may be created using one of the following ORB methods:

  1. org.omg.CORBA.ORB.create_list 
        org.omg.CORBA.NVList nv = orb.create_list(3);
    The variable nv represents a newly-created NVList object. The argument is a memory-management hint to the orb and does not imply the actual length of the list. If, for example, you want to use an NVList object in a request, and the method being invoked takes three parameters, you might optimize by supplying 3 to the method create_list. Note that the new NVList will not necessarily have a length of 3; it could have a length of 2 or 4, for instance. Note also that you can add any number of NamedValue objects to this list regardless of its original length.

  2. org.omg.CORBA.ORB.create_operation_list 
        org.omg.CORBA.NVList nv = orb.create_operation_list(myOperationDef);
    The variable nv represents a newly-created NVList object that contains descriptions of the arguments to the method described in the given OperationDef object.

The methods in the class NVList all deal with the NamedValue objects in the list. There are three methods for adding a NamedValue object, a method for getting the count of NamedValue objects in the list, a method for retrieving a NamedValue object at a given index, and a method for removing a NamedValue object at a given index.

Since:
JDK1.2
See Also:
Request, ServerRequest, NamedValue, Context

 

Constructor Summary

NVList()
    
 

 

Method Summary

abstract  NamedValue add_item(String item_name, int flags)
    Creates a new NamedValue object initialized with the given name and flag, and adds it to the end of this NVList object.
abstract  NamedValue add_value(String item_name, Any val, int flags)
    Creates a new NamedValue object initialized with the given name, value, and flag, and adds it to the end of this NVList object.
abstract  NamedValue add(int flags)
    Creates a new NamedValue object initialized with the given flag and adds it to the end of this NVList object.
abstract  int count()
    Returns the number of NamedValue objects that have been added to this NVList object.
abstract  NamedValue item(int index)
    Retrieves the NamedValue object at the given index.
abstract  void remove(int index)
    Removes the NamedValue object at the given index.
 
Methods inherited from class java.lang.Object
clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait
 

 

Constructor Detail

 

NVList

public NVList()

 

Method Detail

 

count

public abstract int count()
Returns the number of NamedValue objects that have been added to this NVList object.

Returns:
an int indicating the number of NamedValue objects in this NVList.

 

add

public abstract NamedValue add(int flags)
Creates a new NamedValue object initialized with the given flag and adds it to the end of this NVList object. The flag can be any one of the argument passing modes: ARG_IN.value, ARG_OUT.value, or ARG_INOUT.value.

Parameters:
flags - one of the argument mode flags
Returns:
the newly-created NamedValue object

 

add_item

public abstract NamedValue add_item(String item_name,
                                    int flags)
Creates a new NamedValue object initialized with the given name and flag, and adds it to the end of this NVList object. The flag can be any one of the argument passing modes: ARG_IN.value, ARG_OUT.value, or ARG_INOUT.value.

Parameters:
item_name - the name for the new NamedValue object
flags - one of the argument mode flags
Returns:
the newly-created NamedValue object

 

add_value

public abstract NamedValue add_value(String item_name,
                                     Any val,
                                     int flags)
Creates a new NamedValue object initialized with the given name, value, and flag, and adds it to the end of this NVList object.

Parameters:
item_name - the name for the new NamedValue object
val - an Any object containing the value for the new NamedValue object
flags - one of the following argument passing modes: ARG_IN.value, ARG_OUT.value, or ARG_INOUT.value
Returns:
the newly created NamedValue object

 

item

public abstract NamedValue item(int index)
                         throws Bounds
Retrieves the NamedValue object at the given index.

Parameters:
index - the index of the desired NamedValue object, which must be between zero and the length of the list minus one, inclusive. The first item is at index zero.
Returns:
the NamedValue object at the given index
Throws:
Bounds - if the index is greater than or equal to number of NamedValue objects

 

remove

public abstract void remove(int index)
                     throws Bounds
Removes the NamedValue object at the given index. Note that the indices of all NamedValue objects following the one removed are shifted down by one.

Parameters:
index - the index of the NamedValue object to be removed, which must be between zero and the length of the list minus one, inclusive. The first item is at index zero.
Throws:
Bounds - if the index is greater than or equal to number of NamedValue objects in the list