Package bm.machine

Interface StateProvider

All Known Subinterfaces:

FileState, Target

All Known Implementing Classes:

FileBooleanState, FileContentState, FileTarget, FixedStateTarget, StringTarget

Functional Interface:

This is a functional interface and can therefore be used as the assignment target for a lambda expression or method reference.

@FunctionalInterface
public interface StateProvider

Helps to manage the state of a target by persisting its state separately from it to be able to detect when the target and its safed state deviate.

Extracting the state provider from the Target interface, makes it easier to work with pluggable state providers.

Method Summary

Modifier and Type	Method	Description
void	addState(Consumer<byte[]> sink)	Given a sink for byte[] this method should provide bytes representing a target's value.

Method Details

addState

void addState(Consumer<byte[]> sink)
       throws BuildProblemException

Given a sink for byte[] this method should provide bytes representing a target's value. If the value changes, the bytes provided must change too. But the bytes may also change if the value was not actually changed, though this will result in unnecessary builts of a target.

This should not mingle in any dependency data.

As examples consider the full byte content of a file or only its last modified time. The latter changes even if a file is overwritten by itself, but for some cases, i.e. huge files, the time stamp may be preferable.

Parameters:

sink - into which to fill the state representing bytes

Throws:

BuildProblemException - as needed