mongdb

	private Mongo mg = null;

	private DB db;

	private DBCollection users;

	@Before
	public void init() {
		try {
			mg = new Mongo();
			// mg = new Mongo("localhost", 27017);
		} catch (UnknownHostException e) {
			e.printStackTrace();
		} catch (MongoException e) {
			e.printStackTrace();
		}
		// 获取temp DB；如果默认没有创建，mongodb会自动创建
		db = mg.getDB("temp");
		// 获取users DBCollection；如果默认没有创建，mongodb会自动创建
		users = db.getCollection("users");
	}

	@After
	public void destory() {
		if (mg != null)
			mg.close();
		mg = null;
		db = null;
		users = null;
		System.gc();
	}

	private void print(Object o) {
		System.out.println(o);
	}


	@Test
	public void queryAll() {
		print("查询users的所有数据：");
		// db游标
		DBCursor cur = users.find();
		while (cur.hasNext()) {
			print(cur.next());
		}
	}

	@Test
	public void add() {
		// 先查询所有数据
		queryAll();
		print("添加前count: " + users.count());

		DBObject user = new BasicDBObject();
		user.put("name", "Lily");
		user.put("age", 23);
		// users.save(user)保存，getN()获取影响行数

		// print(users.save(user).getN());

		// 扩展字段，随意添加字段，不影响现有数据

		user.put("sex", "女");
		print("添加一条记录后返回影响行数: " + users.save(user).getN());

		// 添加多条数据，传递Array对象
		print("插入数组对象返回影响行数: " +users.insert(user, new BasicDBObject("name", "tom")).getN());

		// 添加List集合
		List<DBObject> list = new ArrayList<DBObject>();
		list.add(user);
		DBObject user2 = new BasicDBObject("name", "lucy");
		user.put("age", 22);
		list.add(user2);

		// 添加List集合
		print("添加List后返回影响行数: " +users.insert(list).getN());

		// 查询下数据，看看是否添加成功
		print("插入后count: " + users.count());
		queryAll();
	}

	@Test
	public void modify() {
		DBObject user = new BasicDBObject();
		user.put("name", "Lucy");
		user.put("age", 35);
		user.put("sex", "女");
		users.update(new BasicDBObject("age", 121) , user); 
		print("已修改");
		queryAll();
	}


	@Test
	public void remove() {
	    queryAll();
	    print("remove age >= 24: " + users.remove(new BasicDBObject("age", new BasicDBObject("$gte", 24))));
	    queryAll();
	}

	@Test
	public void query() {
	    //查询所有
	    //queryAll();
	    //查询id = 4de73f7acd812d61b4626a77
	    print("find id = 4de73f7acd812d61b4626a77: " + users.find(new BasicDBObject("_id", new ObjectId("4de73f7acd812d61b4626a77"))).toArray());
	    //查询age = 24
	    print("find age = 23: " + users.find(new BasicDBObject("age", 23),new BasicDBObject("name", "Lily")).toArray());
	    //查询age >= 24
	    print("find age >= 24: " + users.find(new BasicDBObject("age", new BasicDBObject("$gte", 24))).toArray());
	    print("find age <= 24: " + users.find(new BasicDBObject("age", new BasicDBObject("$lte", 24))).toArray());
	    print("查询age!=25：" + users.find(new BasicDBObject("age", new BasicDBObject("$ne", 25))).toArray());
	    print("查询age in 25/26/27：" + users.find(new BasicDBObject("age", new BasicDBObject(QueryOperators.IN, new int[] { 25, 26, 27 }))).toArray());
	    print("查询age not in 25/26/27：" + users.find(new BasicDBObject("age", new BasicDBObject(QueryOperators.NIN, new int[] { 25, 26, 27 }))).toArray());
	    print("查询age exists 排序：" + users.find(new BasicDBObject("age", new BasicDBObject(QueryOperators.EXISTS, true))).toArray());
	    print("只查询age属性：" + users.find(null, new BasicDBObject("age", true)).toArray());
	    print("只查属性：" + users.find(null, new BasicDBObject("age", true), 0, 2).toArray());
	    print("只查属性：" + users.find(null, new BasicDBObject("age", true), 0, 2, Bytes.QUERYOPTION_NOTIMEOUT).toArray());
	    //只查询一条数据，多条去第一条
	    print("findOne: " + users.findOne());
	    print("findOne: " + users.findOne(new BasicDBObject("age", 26)));
	    print("findOne: " + users.findOne(new BasicDBObject("age", 26), new BasicDBObject("name", true)));
	    //查询修改、删除
	    print("findAndRemove 查询age=25的数据，并且删除: " + users.findAndRemove(new BasicDBObject("age", 25)));
	    //查询age=26的数据，并且修改name的值为Abc
	    print("findAndModify: " + users.findAndModify(new BasicDBObject("age", 26), new BasicDBObject("name", "Abc")));
	    print("findAndModify: " + users.findAndModify(
	        new BasicDBObject("age", 28), //查询age=28的数据
	        new BasicDBObject("name", true), //查询name属性
	        new BasicDBObject("age", true), //按照age排序
	        false, //是否删除，true表示删除
	        new BasicDBObject("name", "Abc"), //修改的值，将name修改成Abc
	        true, 
	        true));
	    queryAll();

	}


	public void testOthers() {
	    DBObject user = new BasicDBObject();
	    user.put("name", "hoojo");
	    user.put("age", 24);

	    //JSON 对象转换        
	    print("serialize: " + JSON.serialize(user));

	    //反序列化
	    print("parse: " + JSON.parse("{ \"name\" : \"hoojo\" , \"age\" : 24}"));

	    print("判断temp Collection是否存在: " + db.collectionExists("temp"));

	    //如果不存在就创建
	    if (!db.collectionExists("temp")) {

	        DBObject options = new BasicDBObject();

	        options.put("size", 20);

	        options.put("capped", 20);

	        options.put("max", 20);

	        print(db.createCollection("account", options));

	    }

	    //设置db为只读
	    db.setReadOnly(true);

	    //只读不能写入数据
	    db.getCollection("test").save(user);
	}

官方API：[url]http://docs.mongodb.org/manual/[/url]