org.afplib.io

Interface ChainLink

All Known Implementing Classes:

AbstractChainLink, NullChain

public interface ChainLink

Represents a link in an AFP filter chain. Links can be chained so that the output of preceding link is the input of the following link.

Method Summary

Modifier and Type	Method and Description
boolean	needTwoPass() signals that this filter wants to read the AFP before actually modifying it.
boolean	onStructuredField(Chain chain, SF sf) is called for each structured field.

Method Detail

needTwoPass

boolean needTwoPass()

signals that this filter wants to read the AFP before actually modifying it. Can be used to first know e.g. which IMMs are used in an AFP file. If needTwoPass returns true, onStructuredField will be first called with chain=null passing all SF for reading. The second pass actually requires a commit call on Chain.

Returns:

true, if this filter wants to read the AFP before modifying it.

onStructuredField

boolean onStructuredField(Chain chain,
                          SF sf)
                   throws IOException

is called for each structured field. The implementing class needs to call commit on Chain for each structured field(s) it wants to be saved. If a filter does not commit the resulting AFP will be empty.

Parameters:

chain - functional interface for committing changes or just passing SFs to the next filter

sf - structured field

Returns:

false, if the work of this filter is done.

Throws:

IOException