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POCompress data in Java and decompress in Python
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  1. POCompress data in Java and decompress in Python
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    copied!<p>So I am trying to compress (gzip or similar format) a JSON object before I throw it in my MySQL database. I am currently storing the data as BLOB. I have tried to use the following Java method to compress the data:</p> <pre><code>public static byte[] compress(String str) throws Exception { if (str == null || str.length() == 0) { return null; } ByteArrayOutputStream obj = new ByteArrayOutputStream(); GZIPOutputStream gzip = new GZIPOutputStream(obj); gzip.write(str.getBytes("UTF-8")); gzip.close(); return obj.toByteArray(); } </code></pre> <p>and then store it in the database using <code>setBytes()</code> with a <code>PreparedStatement</code> and am having no issues with this. What I am having issues with is decrypting the data in Python 2.7 I have tried using <code>zlib.decompress()</code> to no avail. It can't seem to read the data that Java is storing. I also need to write a conversion script in Python to compress the old rows into this new format. So whatever format I needs to be readable by the Python <code>decompress()</code> whether it was compressed with Java or Python 2.7</p> <p>I am happy to provide anymore information that can assist in helping to find a solution to my dilemma.</p> <p>Thanks.</p> <p>EDIT: Some of the Python Code:</p> <pre><code>class KitPvPMatch(Base): """ The SQLAlchemy declarative model class for a User object. """ __tablename__ = 'kit_pvp_matches' __table_args__ = { 'mysql_engine': 'InnoDB', 'mysql_charset': 'utf8' } match_id = Column(INTEGER(11), autoincrement=True, primary_key=True, nullable=False) season = Column(Unicode(5), nullable=False) winner = Column(Unicode(16), nullable=False) loser = Column(Unicode(16), nullable=False) ladder_id = Column(TINYINT(4), nullable=False) data = Column(BLOB, nullable=False) # The line in question jsonData = json.loads(zlib.decompress(match.data)) # The error error: Error -3 while decompressing data: incorrect header check </code></pre>
 

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