MongoDB 增删改查CRUD 操作

愤怒的小草

连接数据库：
Mongo mongo = new Mongo();
DB db = mongo.getDB("todo");
DBCollection items = db.getCollection("items");

创建：
[code]
BasicDBObject doc1 = new BasicDBObject();
doc1.put("task", "Write Code");
doc1.put("priority", "high");
items.insert(doc1);

读取：
BasicDBObject query = new BasicDBObject();
query.put("priority", "highest");
DBCursor cursor = items.find(query);
// Print out "highest" priority items
while (cursor.hasNext()) {
    System.out.println(cursor.next());
}

修改：
BasicDBObject findTestItemQuery = new BasicDBObject();
findTestItemQuery.put("task", "Test Code");
DBCursor testItemsCursor = items.find(findTestItemQuery);
if(testItemsCursor.hasNext()) {
    DBObject testCodeItem = testItemsCursor.next();
    testCodeItem.put("task", "Test and Review Code");
    items.save(testCodeItem);
}

删除：
BasicDBObject deleteQuery = new BasicDBObject();
deleteQuery.put("priority", "highest");
DBCursor cursor = items.find(deleteQuery);
while (cursor.hasNext()) {
    DBObject item = cursor.next();
    items.remove(item);
}