如何壓縮/解壓縮長字符串從PHP到Android？

Question

在我的android應用程序中，它從php下載了一個巨大的字符串。我想壓縮它以節省帶寬。我發現這個頁面http://php.net/manual/en/function.gzcompress.php，它允許我在PHP中壓縮它。但是一旦我在android中使用它，我怎樣才能找回原始字符串？

謝謝

Answer 1

看起來它只是使用gzip壓縮。如果是這樣的話，就來看看：

http://developer.android.com/reference/java/util/zip/GZIPInputStream.html

如果這是不完全所使用的壓縮算法，有幾個內置的算法，可以根據需要使用：

http://developer.android.com/reference/java/util/zip/package-summary.html

Answer 2

在我的情況下，我需要解壓縮在Android中壓縮的PHP字符串，反之亦然，這些字符串由RabbitMQ傳輸。

這是我如何解決它： 在Android中：從Android的

public static byte[] compress(String string) throws IOException { 
    // string = "Lorem ipsum shizzle ma nizle"; 
    byte[] data = string.getBytes("UTF-8"); 
    ByteArrayOutputStream os = new ByteArrayOutputStream(data.length); 
    GZIPOutputStream gos = new GZIPOutputStream(os); 
    gos.write(data); 
    gos.close(); 
    os.close(); 
    return os.toByteArray(); 
} 

public static String decompress(byte[] compressed) throws IOException { 
    final int BUFFER_SIZE = compressed.length; 
    ByteArrayInputStream is = new ByteArrayInputStream(compressed); 
    GZIPInputStream gis = new GZIPInputStream(is, BUFFER_SIZE); 
    StringBuilder string = new StringBuilder(); 
    byte[] data = new byte[BUFFER_SIZE]; 
    int bytesRead; 
    while ((bytesRead = gis.read(data)) != -1) { 
     string.append(new String(data, 0, bytesRead)); 
    } 
    gis.close(); 
    is.close(); 
    return string.toString(); 
} 

RabbitMQ的呼叫：

. 
. 
// Publish 
chan.basicPublish(EXCHANGE, routing_key, MessageProperties.PERSISTENT_BASIC, compress(message.payload)); 
. 
. 
// Subscribe 
String message = decompress(body); 
. 
. 
. 

從的RabbitMQ管理插件，我檢索的Base64編碼版本拉丁語中的字符串，並在PHP中針對此測試應用程序運行它以查看哪個解壓縮方法論作品。

<?php 

$data = "Lorem ipsum shizzle ma nizle"; 
// try all the compression algorithms and out the results in Hex format 
echo "\n\n\n"; 
for($i=-1;$i<=9;$i++) 
    echo chunk_split(strtoupper(bin2hex(gzcompress($data,$i))),2," ") . PHP_EOL ; 
echo "\n\n"; 
for($i=-1;$i<=9;$i++) 
    echo chunk_split(strtoupper(bin2hex(gzdeflate($data,$i))),2," ") . PHP_EOL ; 
echo "\n\n"; 
for($i=-1;$i<=9;$i++) 
    echo chunk_split(strtoupper(bin2hex(gzencode($data,$i,FORCE_GZIP))),2," ") . PHP_EOL; 
echo "\n\n"; 
for($i=-1;$i<=9;$i++) 
    echo chunk_split(strtoupper(bin2hex(gzencode($data,$i,FORCE_DEFLATE))),2," ") . PHP_EOL; 
echo "\n\n"; 


// add the Base64 encoded text from the RabbitMQ plugin 
$data = "H4sIAAAAAAAAAPPJL0rNVcgsKC7NVSjOyKyqyklVyE1UyMsEMgCX3v4lHAAAAA=="; 
$data = base64_decode($data); 
// output the binary version of the compressed string in Hex format 
echo chunk_split(strtoupper(bin2hex($data)),2," ") . PHP_EOL ; 
// match the HEX string to the samples from above as there may be an offset that you need to deal with 

// finally see which of the decompression methods work 
echo gzuncompress($data)."\n"; 
echo gzinflate($data)."\n"; 
echo gzdecode($data)."\n"; 

// Double check that you have the correct one 
$data = "Lorem ipsum shizzle ma nizle"; 
echo chunk_split(strtoupper(bin2hex(gzencode($data,9,FORCE_GZIP))),2," ") . PHP_EOL; 
$data = gzencode($data,9,FORCE_GZIP); 
echo gzdecode($data)."\n"; 

感謝