encode decode bson

Simple BSON JSON encoding decoding test.java

package my.gists.test;

import java.nio.ByteBuffer;
import java.nio.ByteOrder;

import junit.framework.Assert;

import org.junit.Test;

import com.mongodb.BasicDBObject;
import com.mongodb.ByteDecoder;
import com.mongodb.ByteEncoder;
import com.mongodb.DBObject;
import com.mongodb.util.JSON;

/**
 * Simple and naive little test to check out the BSON encoder and decoder.
 * 
 * @author Raymond Roestenburg
 * 
 */
public class BSONTest {

	private BasicDBObject doc;

	public BSONTest() {
		// create a BSON document
		doc = new BasicDBObject();
		doc.put("name", "MongoDB");
		doc.put("type", "database");
		doc.put("count", 1);
	}

	/**
	 * Naive test for encoding and decoding a BSON message
	 */
	@Test
	public void should_encode_and_decode_simple_BSON_message() {
		ByteBuffer b = encode(doc);
		DBObject decoded = decode(b);
		// check it
		assertDoc(decoded);
	}

	@Test
	public void should_encode_and_decode_simple_JSON_to_BSON() {
		String json = "{ \"name\" : \"MongoDB\" , \"type\" : \"database\" , \"count\" : 1}";
		DBObject parsedDoc = (DBObject) JSON.parse(json);
		assertDoc(parsedDoc);
		ByteBuffer buf = encode(parsedDoc);
		DBObject decodedObject = decode(buf);
		assertDoc(decodedObject);
		String jsonResult = JSON.serialize(decodedObject);
		Assert.assertEquals(jsonResult, json);

	}

	private void assertDoc(DBObject returned) {
		Assert.assertEquals("MongoDB", returned.get("name"));
		Assert.assertEquals("database", returned.get("type"));
		Assert.assertEquals(1, returned.get("count"));
	}

	private ByteBuffer encode(DBObject dbObject) {
		// encode one single document
		ByteEncoder encoder = ByteEncoder.get();
		encoder.putObject(dbObject);

		// get the result from the encoder
		byte[] bytes = encoder.getBytes();
		ByteBuffer buf = ByteBuffer.allocate(bytes.length);

		// BSON is in little endian byte order. put it in a buffer
		buf.order(ByteOrder.LITTLE_ENDIAN);
		buf.put(bytes);
		buf.rewind();
		return buf;
	}

	private DBObject decode(ByteBuffer b) {
		// decode de BSON message
		ByteDecoder decoder = new ByteDecoder(b);
		return decoder.readObject();
	}

}