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package org.openide.loaders;

import org.openide.filesystems.FileObject;

/**
 * Pair of dataobject invalidation sequence # and primary file.
 * It serves as a key for the given data object.
 * It is here to create something different then data object,
 * because the data object should be finalized when not needed and
 * that is why it should not be used as a key.
 */
final class FolderChildrenPair extends Object {

    public final FileObject primaryFile;
    public final int seq;

    FolderChildrenPair(FileObject primaryFile) {
        super();
        this.primaryFile = primaryFile;
        this.seq = DataObjectPool.getPOOL().registrationCount(primaryFile);
    }

    @Override
    public int hashCode() {
        return primaryFile.hashCode() ^ seq;
    }

    @Override
    public boolean equals(Object o) {
        if (o instanceof FolderChildrenPair) {
            FolderChildrenPair p = (FolderChildrenPair) o;
            if (!primaryFile.equals(p.primaryFile)) {
                return false;
            }
            if (seq == -1 || p.seq == -1) {
                return true;
            }
            return seq == p.seq;
        }
        return false;
    }

    @Override
    public String toString() {
        return "FolderChildren.Pair[" + primaryFile + "," + seq + "]";
    }
}