解压缩文件将文件转换为字节

Question

我有应用程序从 url 下载 .zip 文件并将每个文件从 .zip 文件转换为字节数组。目前我能够下载文件读取 .zip 文件并将整个 .zip 文件转换为字节，但在将 .zip 中的每个文件转换为字节数组时遇到了麻烦。任何帮助将不胜感激。我在下面附上了我的代码：

try {
    URL url = new URL(Url);
    //create the new connection
    HttpURLConnection urlConnection = (HttpURLConnection)                                url.openConnection();

    //set up some things on the connection
    urlConnection.setRequestMethod("GET");
    urlConnection.setDoOutput(true); 
    //and connect!
    urlConnection.connect();
    //set the path where we want to save the file
    //in this case, going to save it on the root directory of the
    //sd card.
    InputStream inputStream = urlConnection.getInputStream();
    dis = new DataInputStream(new BufferedInputStream(inputStream));
    System.out.println("INput connection done>>>>>");

    zis = new ZipInputStream(new BufferedInputStream(dis));

    String targetFolder="/sdcard/";

    System.out.println("zip available is"+zis.available());

    int extracted = 0;

    while ((entry = zis.getNextEntry()) != null) {
        ByteArrayOutputStream baos = new ByteArrayOutputStream();
        byte[] buffer = new byte[1024];
        int count;

        while ((count = zis.read(buffer)) != -1) {
            baos.write(buffer, 0, count);
        }

        String filename = entry.getName();
        System.out.println("File name is>>"+filename);

        byte[] bytes = baos.toByteArray();
        System.out.println("Bytes is >>>>"+bytes.toString());
        // do something with 'filename' and 'bytes'...
        zis.closeEntry();

        extracted ++;
    }

    zis.close();

} catch (FileNotFoundException e) {
    e.printStackTrace();
} catch (IOException e) {
    e.printStackTrace();
}

Answer 1

您的while ((count = zis.read(buffer)) != -1) 行循环读取整个zip 文件。你想做的是count = zis.read(buffer, 0, entry.getSize())。这将在一个命令中将每个 zip 文件条目的内容转储到缓冲区中。

你会想要使这个字节数组更大。

或者，您可以保留小缓冲区，但只需确保在主循环的每次迭代中，您只读取 entry.getSize() 字节，否则您最终会读取整个文件。

Answer 2

根据 Jon7 的回答（如果这能解决您的问题，他真的应该得到赞扬），试试这个：

while ((entry = zis.getNextEntry()) != null) {
    String filename = entry.getName();
    int needed = entry.getSize();
    byte[] bytes = new byte[needed];
    int pos = 0;
    while (needed > 0) {
        int read = zis.read(bytes, pos, needed);
        if (read == -1) {
            // end of stream -- OOPS!
            throw new IOException("Unexpected end of stream after " + pos + " bytes for entry " + filename);
        }
        pos += read;
        needed -= read;
    }

    System.out.println("File name is>>"+filename);
    System.out.println("Bytes is >>>>"+bytes.toString());
    // do something with 'filename' and 'bytes'...
    zis.closeEntry();

    extracted ++;
}