GZip in android [duplicate]
How to compress and decompress a file in android using GZip. please provide with some reference , so that it would a great help for me.
Thanks in advance
Please use the following methods to compress the string using gzip.
public static byte[] compress(String string) throws IOException {
ByteArrayOutputStream os = new ByteArrayOutputStream(string.length());
GZIPOutputStream gos = new GZIPOutputStream(os);
gos.write(string.getBytes());
gos.close();
byte[] compressed = os.toByteArray();
os.close();
return compressed;
}
public static String decompress(byte[] compressed) throws IOException {
final int BUFFER_SIZE = 32;
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();
}
Check out GZIPInputStream
and GZIPOutputStream
.
I ran into same problem some time ago. Here are the functions i used
Compress Function
if (responseCode == HttpConnection.HTTP_OK){
boolean stop = false, pause = false;
totalSize = conn.getLength() + downloaded;
chunkSize = (int)(conn.getLength() / 100);
System.out.println("*********-----" + conn.getLength() + "");
System.out.println("-----------------ok");
in = conn.openInputStream();
int length = 0, s = 0;
byte[] readBlock = new byte[(int)conn.getLength()];
while ((s = in.read(readBlock) != -1)
length = length + s;
{
if (!pause)
{
readBlock = Decompress.decompress(readBlock);
out.write(readBlock, 0, length);
downloaded += length;
int a = getPerComplete(totalSize, downloaded);
System.out.println("% OF Downloaded--------" + a);
int a1 = getPerComplete(totalSize, downloaded);
Decompress function:-
public byte[] decompress(byte[] compressed) throws IOException
{
GZIPInputStream gzipInputStream;
if (compressed.length > 4)
{
gzipInputStream = new GZIPInputStream(
new ByteArrayInputStream(compressed, 4,
compressed.length - 4));
ByteArrayOutputStream baos = new ByteArrayOutputStream();
for (int value = 0; value != -1;)
{
value = gzipInputStream.read();
if (value != -1)
{
baos.write(value);
}
}
gzipInputStream.close();
baos.close();
return baos.toByteArray();
}
else
{
return null;
}
}
}
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