public class

CommandInfo

extends Object
java.lang.Object
   ↳ com.google.code.javax.activation.CommandInfo

Class Overview

The CommandInfo class is used by CommandMap implementations to describe the results of command requests. It provides the requestor with both the verb requested, as well as an instance of the bean. There is also a method that will return the name of the class that implements the command but it is not guaranteed to return a valid value. The reason for this is to allow CommandMap implmentations that subclass CommandInfo to provide special behavior. For example a CommandMap could dynamically generate JavaBeans. In this case, it might not be possible to create an object with all the correct state information solely from the class name.

Summary

Fields
private String className
private String verb
Public Constructors
CommandInfo(String verb, String className)
The Constructor for CommandInfo.
Public Methods
String getCommandClass()
Return the command's class name.
String getCommandName()
Return the command verb.
Object getCommandObject(DataHandler dh, ClassLoader loader)
Return the instantiated JavaBean component.
[Expand]
Inherited Methods
From class java.lang.Object

Fields

private String className

private String verb

Public Constructors

public CommandInfo (String verb, String className)

The Constructor for CommandInfo.

Parameters
verb The command verb this CommandInfo decribes.
className The command's fully qualified class name.

Public Methods

public String getCommandClass ()

Return the command's class name. This method MAY return null in cases where a CommandMap subclassed CommandInfo for its own purposes. In other words, it might not be possible to create the correct state in the command by merely knowing its class name. DO NOT DEPEND ON THIS METHOD RETURNING A VALID VALUE!

Returns
  • The class name of the command, or null

public String getCommandName ()

Return the command verb.

Returns
  • the command verb.

public Object getCommandObject (DataHandler dh, ClassLoader loader)

Return the instantiated JavaBean component.

Begin by instantiating the component with Beans.instantiate().

If the bean implements the javax.activation.CommandObject interface, call its setCommandContext method.

If the DataHandler parameter is null, then the bean is instantiated with no data. NOTE: this may be useful if for some reason the DataHandler that is passed in throws IOExceptions when this method attempts to access its InputStream. It will allow the caller to retrieve a reference to the bean if it can be instantiated.

If the bean does NOT implement the CommandObject interface, this method will check if it implements the java.io.Externalizable interface. If it does, the bean's readExternal method will be called if an InputStream can be acquired from the DataHandler.

Parameters
dh The DataHandler that describes the data to be passed to the command.
loader The ClassLoader to be used to instantiate the bean.
Returns
  • The bean
Throws
ClassNotFoundException
IOException
See Also