Getting the entry from a ZipInputStream

Finally I found the code to get an entry from an InputStream that contains zipped data. For a ZipFileInputStream this is easy, but not for a regular input stream because the size of the entry can be unknown (-1) and there is no alternative then just go through the stream.

sorry for the messy mark-up...

disclaimer: code is not optimized!

// based on http://java.sun.com/developer/technicalArticles/Programming/compression/

public static String unzipEntry(InputStream zippedInputStream, String entryName) throws Exception {
String result = null;
final int BUFFER = 2048;
BufferedOutputStream dest = null;
ZipInputStream zis = new ZipInputStream(new BufferedInputStream(zippedInputStream));
ZipEntry entry;
while((entry = zis.getNextEntry()) != null) {
int count;
byte data[] = new byte[BUFFER];
StringOutputStream fos = new StringOutputStream();
dest = new BufferedOutputStream(fos, BUFFER);
while ((count = zis.read(data, 0, BUFFER)) != -1) {
dest.write(data, 0, count);
}
dest.flush();
dest.close();
if (entryName.equals(entry.getName())) {
result = fos.toString();
}
}
zis.close();
return result;
}

public class StringOutputStream extends OutputStream {

// This buffer will contain the stream
protected StringBuffer buf = new StringBuffer();

public StringOutputStream() {}

public void close() {}

public void flush() {}

public void write(byte[] b) {
String str = new String(b);
this.buf.append(str);
}

public void write(byte[] b, int off, int len) {
String str = new String(b, off, len);
this.buf.append(str);
}

public void write(int b) {
String str = Integer.toString(b);
this.buf.append(str);
}

public String toString() {
return buf.toString();
}

public int contains(String string) {
return StringUtils.countOccurrencesOf(buf.toString(), string);
}


}