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Provides basic functionality for reading and writing ZIP files.

There is a newer version: 0.14.0

/*
 * Copyright (C) 2005-2015 Schlichtherle IT Services.
 * All rights reserved. Use is subject to license terms.
 */
package net.java.truevfs.comp.zip;

/**
 * Provides parameters for reading ZIP files.
 * 
 * Warning: This interface is not intended for public use
 * - its API may change at will without prior notification!
 *
 * @param   The type of the created ZIP entries.
 * @author Christian Schlichtherle
 */
public interface ZipFileParameters
extends ZipCharsetParameters, ZipEntryFactory {

    /**
     * Returns the flag for supporting preambles.
     * If this method returns {@code true}, then a ZIP file is allowed to
     * contain arbitrary data as its preamble before the actual ZIP file data.
     * Self Extracting Archives typically use a preamble to store the
     * application code that is required to extract the ZIP file contents.
     * 

     * If this method returns {@code false}, then a ZIP file must start with
     * either a Local File Header (LFH) signature,
     * a ZIP64 End Of Central Directory Record (EOCDR) signature or an End Of
     * Central Directory Record (EOCDR) signature.
     *
     * @return The flag for allowing a preamble.
     */
    boolean getPreambled();

    /**
     * Returns the flag for supporting postambles of arbitrary length.
     * If this method returns {@code true}, then a ZIP file is allowed to
     * contain arbitrary data of arbitrary length as its postamble after the
     * actual ZIP file data.
     * Note that searching for an arbitrary length postamble can seriously
     * degrade the performance when reading a false positive ZIP file, i.e.
     * an arbitrary file which is not compatible to the ZIP File Format
     * Specification, because then the entire file needs to get searched for
     * an End Of Central Directory Record (EOCDR) signature.
     * A valid use case are self extracting ZIP files with very large
     * postambles to host the extraction code.
     * 
     * If this method returns {@code false}, then a ZIP file may still have a
     * postamble, but it must not exceed 64KB size, including the End Of
     * Central Directory record with the ZIP file comment.
     * This causes the reading of a false positive ZIP file to fail fast.
     *
     * @return The flag for supporting postambles of arbitrary length.
     */
    boolean getPostambled();
}