VirtualIteratorForFileSystems.java

package dk.statsbiblioteket.medieplatform.autonomous.iterator.filesystem.transforming;

import dk.statsbiblioteket.medieplatform.autonomous.iterator.common.DelegatingTreeIterator;

import java.io.File;
import java.util.ArrayList;
import java.util.Collection;
import java.util.Iterator;
import java.util.List;

/**
 * This class represents an iterator over a virtual folder, ie. a folder representing a group of files with identical
 * prefixes
 */
public class VirtualIteratorForFileSystems extends CommonTransformingIterator {
    protected String prefix;
    private List<File> group;
    private List<DelegatingTreeIterator> virtualChildren;


    public VirtualIteratorForFileSystems(File id, String prefix, File batchFolder, String dataFilePattern,
                                         List<File> group, String groupingChar, String checksumPostfix) {
        super(new File(id, prefix), batchFolder, dataFilePattern, checksumPostfix, groupingChar);
        this.prefix = prefix;
        this.group = group;
        virtualChildren = new ArrayList<>();
    }

    @Override
    protected Iterator<DelegatingTreeIterator> initializeChildrenIterator() {
        return virtualChildren.iterator();
    }

    @Override
    protected Iterator<File> initilizeAttributeIterator() {
        Collection<File> datafiles = getDataFiles(group);
        for (File dataFile : datafiles) {
            group.remove(dataFile);
            virtualChildren.add(
                    new DatafileIterator(
                            dataFile, getBatchFolder(), getChecksumPostfix(), getGroupingChar()));
        }
        return group.iterator();
    }

}