Question

I need to store a binary object (java class having several collections inside) in the key-value storage.
The size limit for the value is 4K.
I created XStream based serializer and deserializer, so when I am done filling my class members I can serialize it to a String or to a file.
In the worst case the serialized String/file size is ~30K. I mange to achive good compression rate so after compression my file is ~2K which fits the bill.

My question: is there any useful java API\library\technique that can:

1. compress a String and serialize the compressed object.
2. decompress previously compressed object and create a regular String from it

I am looking for one-liners that do not require intermediate storage of serialized object to file for later compression.

Appreciate your help!

Answer 1

Try a GZIPOutputStream for zipping the String:

ByteArrayOutputStream out = new ByteArrayOutputStream();
Writer writer = new BufferedWriter(new OutputStreamWriter(new GZIPOutputStream(out)));
writer.write(string);
byte[] zipped = out.toByteArray();

And to unzip again:

ByteArrayInputStream in = new ByteArrayInputStream(zipped);
BufferedReader reader = new BufferedReader(new InputStreamReader(new GZIPInputStream(in)));
string = reader.readLine();