不能提取在Android上创建ZIP压缩文件（设备/特定操作系统） [英] Cannot extract file from ZIP archive created on Android (device/OS specific)

问题描述

我现在用的是code这样的创建Android上的存档：

I am creating an archive on Android using the code like this:

    OutputStream os = new FileOutputStream(zipFile);
    ZipOutputStream zos = new ZipOutputStream(new BufferedOutputStream(os));
    try 
    {
        zos.setLevel(8);
        byte[] buffer = new byte[32768];
        for (VFile src : toPack)            
        {
            ZipEntry entry = new ZipEntry(src.name);
            zos.putNextEntry(entry);
            src.pushToStream(zos, buffer);
            src.close();
            zos.closeEntry();
        }
    }
    finally 
    {
        zos.close();
    }       

我发现里面只有一个COM pression方法可用 - DEFLATED （这里只有存储的替代可用）。这意味着，归档始终COM pressed用一种方法。

I found that there's only one compression method available - DEFLATED (there's only STORED alternative available). This means that archive is always compressed with one method.

如果我运行在Android上2.3.4本code - 我可以DECOM preSS Windows中使用7Zip的文件中;如果我运行这个在Android 3（或三星Galaxy Tab，不知道谁做是错误的） - 7Zip的显示归档列表，但不能DECOM preSS文件说的不支持COM pression方法的。同时7Zip的表演的减缩的作为文件COM pression方法，这意味着它可以正确地对待它。

If I run this code on Android 2.3.4 - I can decompress files in Windows using 7Zip; if I run this on Android 3 (or Samsung Galaxy Tab; not sure who makes it wrong) - 7Zip shows archive list, but cannot decompress file saying Unsupported compression method. At the same time 7Zip shows Deflate as a compression method on file which means it can treat it properly.

没有人也有这个问题？

感谢。

UDP：发现了另一个<一href="http://stackoverflow.com/questions/10070387/how-can-i-zip-a-text-using-gzipoutputstream-that-is-compatible-with-net-zip-alg">topic类似的问题（可能是虽然不是一样的）。

UDP: Found another topic with similar issue (may be not same though).

推荐答案

在@ user1269737的答案是正确的;几乎。但它仅适用于一个单一的文件档案。 下面是一个code的解析整个档案。

The @user1269737's answer is correct; almost. But it only works for a single-file archives. Below is a code which parses the whole archive.

/**
* Replace wrong local file header byte
* http://sourceforge.net/tracker/?func=detail&aid=3477810&group_id=14481&atid=114481
* Applies to Android API 9-13
* @param zip file
* @throws IOException
*/
private static void fixInvalidZipFile(File zip) throws IOException 
{
    RandomAccessFile r = new RandomAccessFile(zip, "rw");
    try
    {
        long eocd_offset = findEOCDRecord(r);

        if (eocd_offset > 0)
        {
            r.seek(eocd_offset + 16);  // offset of first CDE in EOCD               
            long cde_offset = readInt(r);  // read offset of first Central Directory Entry
            long lfh_offset = 0;
            long fskip, dskip;

            while (true)
            {
                r.seek(cde_offset);
                if (readInt(r) != CDE_SIGNATURE)  // got off sync!
                    return;

                r.seek(cde_offset + 20);  // compressed file size offset                
                fskip = readInt(r);

                // fix the header
                //
                r.seek(lfh_offset + 7);
                short localFlagsHi = r.readByte();  // hi-order byte of local header flags (general purpose)
                r.seek(cde_offset + 9);
                short realFlagsHi = r.readByte();  // hi-order byte of central directory flags (general purpose)
                if (localFlagsHi != realFlagsHi)
                { // in latest versions this bug is fixed, so we're checking is bug exists.
                    r.seek(lfh_offset + 7);
                    r.write(realFlagsHi);
                }

                //  calculate offset of next Central Directory Entry
                //
                r.seek(cde_offset + 28);  // offset of variable CDE parts length in CDE
                dskip = 46;  // length of fixed CDE part
                dskip += readShort(r);  // file name
                dskip += readShort(r);  // extra field
                dskip += readShort(r);  // file comment

                cde_offset += dskip;
                if (cde_offset >= eocd_offset)  // finished!
                    break;              

                // calculate offset of next Local File Header
                //
                r.seek(lfh_offset + 26);  // offset of variable LFH parts length in LFH
                fskip += readShort(r);  // file name
                fskip += readShort(r);  // extra field
                fskip += 30;  // length of fixed LFH part
                fskip += 16;  // length of Data Descriptor (written after file data)

                lfh_offset += fskip;
            }
        }
    }
    finally
    {
        r.close();
    }
}

//http://www.pkware.com/documents/casestudies/APPNOTE.TXT
private static final int LFH_SIGNATURE = 0x04034b50;
private static final int DD_SIGNATURE = 0x08074b50;
private static final int CDE_SIGNATURE = 0x02014b50;
private static final int EOCD_SIGNATURE = 0x06054b50;

/** Find an offset of End Of Central Directory record in file */
private static long findEOCDRecord(RandomAccessFile f) throws IOException
{
    long result = f.length() - 22; // 22 is minimal EOCD record length
    while (result > 0)
    {
        f.seek(result);

        if (readInt(f) == EOCD_SIGNATURE) return result;

        result--;
    }
    return -1;
}

/** Read a 4-byte integer from file converting endianness. */
private static int readInt(RandomAccessFile f) throws IOException
{
    int result = 0;
    result |= f.read();
    result |= (f.read() << 8);
    result |= (f.read() << 16);
    result |= (f.read() << 24);
    return result;
}

/** Read a 2-byte integer from file converting endianness. */
private static short readShort(RandomAccessFile f) throws IOException
{
    short result = 0;
    result |= f.read();
    result |= (f.read() << 8);
    return result;
}

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