uk.org.ogsadai.activity.xmldb.commands
Interface CommandContext

All Known Implementing Classes:

CommandContextImpl

public interface CommandContext

A CommandContext allows a command to access the objects that it can interact with. For example, an command to add a new resource might get a collection, using the getCollection method, then get the new resource from an input, using the getInput method, before writing some results to the output, retrieved with the getOutput method.

Author:

The OGSA-DAI Project

getCollection

public org.xmldb.api.base.Collection getCollection()

Gets the open Collection that the command will be interact with.

Returns:

an open Collection object. It is not the command's responsibility to close this.

getInput

public BlockReader getInput(java.lang.String inputName)
                     throws XMLDBStreamNotFoundException

Get the named input for the Command to interact with.

Parameters:

inputName - The name of the input.

Returns:

a BlockReader from which the input can be read.

Throws:

XMLDBStreamNotFoundException - If there is no such input stream.

getOutput

public BlockWriter getOutput()
                      throws XMLDBStreamNotFoundException

Gets the output for the command to write any results to.

Returns:

a BlockWriter to which the output can be written.

Throws:

XMLDBStreamNotFoundException - If there is no output stream.