Java ZipEntry Read getZipEntryByteContent(ZipEntry ze, ZipFile zip)

Description

Returns the contents of the given zip entry as a byte array.

License

Open Source License

Exception

Parameter	Description
IOException	if a problem occured reading the zip entry.

Declaration

public static byte[] getZipEntryByteContent(ZipEntry ze, ZipFile zip) throws IOException 

Method Source Code

//package com.java2s;
/*******************************************************************************
 * Copyright ? 2000, 2013 IBM Corporation and others.
 * All rights reserved. This program and the accompanying materials
 * are made available under the terms of the Eclipse Public License v1.0
 * which accompanies this distribution, and is available at
 * http://www.eclipse.org/legal/epl-v10.html
 *
 * Contributors:/* w  ww  . j  a v  a 2  s. c o m*/
 * IBM Corporation - initial API and implementation
 *
 *******************************************************************************/

import java.io.BufferedInputStream;

import java.io.IOException;
import java.io.InputStream;

import java.util.zip.ZipEntry;
import java.util.zip.ZipFile;

public class Main {
    private static final int DEFAULT_READING_SIZE = 8192;

    /**
     * Returns the contents of the given zip entry as a byte array.
     * @throws IOException if a problem occured reading the zip entry.
     */
    public static byte[] getZipEntryByteContent(ZipEntry ze, ZipFile zip) throws IOException {

        InputStream stream = null;
        try {
            stream = new BufferedInputStream(zip.getInputStream(ze));
            return getInputStreamAsByteArray(stream, (int) ze.getSize());
        } finally {
            if (stream != null) {
                try {
                    stream.close();
                } catch (IOException e) {
                }
            }
        }
    }

    /**
     * Returns the given input stream's contents as a byte array.
     * If a length is specified (ie. if length != -1), only length bytes
     * are returned. Otherwise all bytes in the stream are returned.
     * Note this doesn't close the stream.
     * @throws IOException if a problem occured reading the stream.
     */
    public static byte[] getInputStreamAsByteArray(InputStream stream, int length) throws IOException {
        byte[] contents;
        if (length == -1) {
            contents = new byte[0];
            int contentsLength = 0;
            int amountRead = -1;
            do {
                int amountRequested = Math.max(stream.available(), DEFAULT_READING_SIZE); // read at least 8K

                // resize contents if needed
                if (contentsLength + amountRequested > contents.length) {
                    System.arraycopy(contents, 0, contents = new byte[contentsLength + amountRequested], 0,
                            contentsLength);
                }

                // read as many bytes as possible
                amountRead = stream.read(contents, contentsLength, amountRequested);

                if (amountRead > 0) {
                    // remember length of contents
                    contentsLength += amountRead;
                }
            } while (amountRead != -1);

            // resize contents if necessary
            if (contentsLength < contents.length) {
                System.arraycopy(contents, 0, contents = new byte[contentsLength], 0, contentsLength);
            }
        } else {
            contents = new byte[length];
            int len = 0;
            int readSize = 0;
            while ((readSize != -1) && (len != length)) {
                // See PR 1FMS89U
                // We record first the read size. In this case len is the actual read size.
                len += readSize;
                readSize = stream.read(contents, len, length - len);
            }
        }

        return contents;
    }
}

Related

1. getZipEntry(ZipFile jarFile, String path)
2. getZipEntry(ZipFile zip, final String name)
3. getZipEntry(ZipFile zip, String name)
4. getZipEntryAsString(File archive, String name)
5. getZipEntryAsString(InputStream is)
6. getZipEntryContent(final File zip, final String entry)
7. getZipEntryFileName(final ZipEntry zipEntry)
8. getZipEntryName(int pathOffset, String absolutePath)
9. getZipEntryNames(File zipFile)