ZipEntryUtil.java

package com.smartandroid.sa.zip;

import java.io.BufferedInputStream;
import java.io.IOException;
import java.io.InputStream;
import java.util.zip.ZipEntry;
import java.util.zip.ZipOutputStream;

import com.smartandroid.sa.zip.commons.IOUtils;

/**
 * Util class for static methods shared between ZipUtil and Zips.
 * 
 * @author shelajev
 * 
 */
class ZipEntryUtil {

	private ZipEntryUtil() {
	}

	/**
	 * Copy entry
	 * 
	 * @param original
	 *            - zipEntry to copy
	 * @return copy of the original entry
	 */
	static ZipEntry copy(ZipEntry original) {
		return copy(original, null);
	}

	/**
	 * Copy entry with another name.
	 * 
	 * @param original
	 *            - zipEntry to copy
	 * @param newName
	 *            - new entry name, optional, if null, ogirinal's entry
	 * @return copy of the original entry, but with the given name
	 */
	static ZipEntry copy(ZipEntry original, String newName) {
		ZipEntry copy = new ZipEntry(newName == null ? original.getName()
				: newName);
		if (original.getCrc() != -1) {
			copy.setCrc(original.getCrc());
		}
		if (original.getMethod() != -1) {
			copy.setMethod(original.getMethod());
		}
		if (original.getSize() >= 0) {
			copy.setSize(original.getSize());
		}
		if (original.getExtra() != null) {
			copy.setExtra(original.getExtra());
		}

		copy.setComment(original.getComment());
		copy.setTime(original.getTime());
		return copy;
	}

	/**
	 * Copies a given ZIP entry to a ZIP file.
	 * 
	 * @param zipEntry
	 *            a ZIP entry from existing ZIP file.
	 * @param in
	 *            contents of the ZIP entry.
	 * @param out
	 *            target ZIP stream.
	 */
	static void copyEntry(ZipEntry zipEntry, InputStream in, ZipOutputStream out)
			throws IOException {
		copyEntry(zipEntry, in, out, true);
	}

	/**
	 * Copies a given ZIP entry to a ZIP file. If this.preserveTimestamps is
	 * true, original timestamp is carried over, otherwise uses current time.
	 * 
	 * @param zipEntry
	 *            a ZIP entry from existing ZIP file.
	 * @param in
	 *            contents of the ZIP entry.
	 * @param out
	 *            target ZIP stream.
	 */
	static void copyEntry(ZipEntry zipEntry, InputStream in,
			ZipOutputStream out, boolean preserveTimestamps) throws IOException {
		ZipEntry copy = copy(zipEntry);
		copy.setTime(preserveTimestamps ? zipEntry.getTime() : System
				.currentTimeMillis());
		addEntry(copy, new BufferedInputStream(in), out);
	}

	/**
	 * Adds a given ZIP entry to a ZIP file.
	 * 
	 * @param zipEntry
	 *            new ZIP entry.
	 * @param in
	 *            contents of the ZIP entry.
	 * @param out
	 *            target ZIP stream.
	 */
	static void addEntry(ZipEntry zipEntry, InputStream in, ZipOutputStream out)
			throws IOException {
		out.putNextEntry(zipEntry);
		if (in != null) {
			IOUtils.copy(in, out);
		}
		out.closeEntry();
	}

}