HistoryEventDifferenceHandler.java

package fr.openwide.core.jpa.more.business.history.util;

import java.util.Arrays;
import java.util.List;

import org.bindgen.BindingRoot;
import org.springframework.beans.factory.annotation.Autowired;

import com.google.common.collect.ImmutableList;
import com.google.common.collect.Iterables;

import de.danielbechler.diff.path.NodePath;
import fr.openwide.core.commons.util.fieldpath.FieldPath;
import fr.openwide.core.jpa.more.business.difference.model.Difference;
import fr.openwide.core.jpa.more.business.difference.util.DiffUtils;
import fr.openwide.core.jpa.more.business.history.model.AbstractHistoryLog;
import fr.openwide.core.jpa.more.business.history.model.embeddable.HistoryEventSummary;
import fr.openwide.core.jpa.more.business.history.service.IGenericHistoryEventSummaryService;

/**
 * A {@link IHistoryDifferenceHandler} that will
 * {@link IGenericHistoryEventSummaryService#refresh(HistoryEventSummary, AbstractHistoryLog) refresh} a
 * {@link HistoryEventSummary} whenever differences are detected on particular paths.
 */
public class HistoryEventDifferenceHandler<T, HL extends AbstractHistoryLog<?, ?, ?>>
		implements IHistoryDifferenceHandler<T, HL> {
	
	@Autowired
	private IGenericHistoryEventSummaryService<?> historyEventSummaryService;
	
	private final BindingRoot<T, HistoryEventSummary> bindingToEventToRefresh;
	
	private final List<NodePath> pathsToCheck;

	public HistoryEventDifferenceHandler(BindingRoot<T, HistoryEventSummary> bindingToEventToRefresh, FieldPath ... pathsToCheck) {
		this(bindingToEventToRefresh, Iterables.transform(Arrays.asList(pathsToCheck), DiffUtils.toNodePathFunction()));
	}

	public HistoryEventDifferenceHandler(BindingRoot<T, HistoryEventSummary> bindingToEventToRefresh, Iterable<NodePath> pathsToCheck) {
		super();
		this.bindingToEventToRefresh = bindingToEventToRefresh;
		this.pathsToCheck = ImmutableList.copyOf(pathsToCheck);
	}

	@Override
	public void handle(T entity, Difference<? extends T> difference, HL historyLog) {
		for (NodePath path : pathsToCheck) {
			if (difference.hasChange(path)) {
				HistoryEventSummary evenement = bindingToEventToRefresh.getSafelyWithRoot(entity);
				historyEventSummaryService.refresh(evenement, historyLog);
				return;
			}
		}
	}
}