What's That Noise?! [Ian Kallen's Weblog]

Tuesday April 12, 2005

Hello Berkeley DB This morning, I wanted to get familiar with the Berkeley DB "Java Edition" API (that's a mouthful, can't I just call it "sleepycat"?). I was in a carpool and I don't think the dude driving realized I was hacking-in-traffic. While I've happily used used DB_File in Perl for years-n-years, I haven't had time/opportunity to mess with the Java stuff from Sleepycat. However, at work we're cooking up a durable message buffer with an embedded servlet container, fun! As with poking into any new API, I like to start with Hello World.

Here's my Sleepycat Hello World

import com.sleepycat.je.Cursor;
import com.sleepycat.je.Database;
import com.sleepycat.je.DatabaseEntry;
import com.sleepycat.je.DatabaseConfig;
import com.sleepycat.je.DatabaseException;
import com.sleepycat.je.Environment;
import com.sleepycat.je.EnvironmentConfig;
import com.sleepycat.je.LockMode;
import com.sleepycat.je.OperationStatus;
import java.io.File;

public class HelloBdb {

    public static void main(String[] args) throws Exception {
        String key = args[0];
        String value = args[1];

        File dir = new File("db");
        dir.mkdirs();

        Environment env = new Environment(dir, new EnvironmentConfig());
        Database database = env.openDatabase(null, "foobar", new DatabaseConfig());
        database.put(null, 
            new DatabaseEntry(key.getBytes()), new DatabaseEntry(value.getBytes()));

        DatabaseEntry foundKey = new DatabaseEntry();
        DatabaseEntry foundData = new DatabaseEntry();

        Cursor cursor = database.openCursor(null, null);
        while (cursor.getNext(foundKey, foundData, LockMode.DEFAULT) == 
                OperationStatus.SUCCESS) {
            String keyString = new String(foundKey.getData());
            String dataString = new String(foundData.getData());
            System.out.println("Key | Data : " + keyString + " | " + 
                dataString + "");
        }
        cursor.close();
        database.close();
        env.close();
    }
}

Of course, the real fun will be running this in a multi-threaded environment and the concurrency issues therein. With Hello World done, it's time to move on to see what else needs to be added to the cookbook.

( Apr 12 2005, 08:57:09 PM PDT ) Permalink

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