Java-MongoDB入门级小程序，方便直接上手使用

<dependency>
<groupId>org.mongodb</groupId>
<artifactId>mongo-java-driver</artifactId>
<version>3.2.2</version>
</dependency>

// 连接MongoDB数据库无需认证
public static void noAuthorise() {
MongoClient mongoClient = null;
try {
// 连接到mongodb服务
mongoClient = new MongoClient("localhost", 27017);
// 连接数据库名称为col的
MongoDatabase mongoDatabase = mongoClient.getDatabase("col");
System.out.println("Connect to database successfully");
} catch (Exception e) {
e.printStackTrace();
} finally {
if (mongoClient != null)
mongoClient.close();
}
}

// 连接MongoDB数据库需要认证条件
public static void connServer() {
MongoClient mongoClient = null;
try {
// 连接到Mongodb服务
ServerAddress serverAddress = new ServerAddress("localhost", 27017);
List<ServerAddress> addrs = new ArrayList<>();
addrs.add(serverAddress);
// MongoCredential.createScramSha1Credential()三个参数分别为 用户名 数据库名称 密码
MongoCredential credential = MongoCredential.createScramSha1Credential("username", "databaseName",
"password".toCharArray());
List<MongoCredential> credentials = new ArrayList<MongoCredential>();
credentials.add(credential);
// 通过连接认证获取MongoDB连接
mongoClient = new MongoClient(addrs, credentials);
// 连接到数据库
MongoDatabase mongoDatabase = mongoClient.getDatabase("databaseName");
System.out.println("Connect to database successfully!");
} catch (Exception e) {
// TODO 自动生成的 catch 块
e.printStackTrace();
} finally {
if (mongoClient != null)
mongoClient.close();
}

}

// 创建集合
public static void createCollection() {
MongoClient mongoClient = null;
try {
// 连接到mongodb服务
mongoClient = new MongoClient("localhost", 27017);
// 连接到数据库
MongoDatabase mongoDatabase = mongoClient.getDatabase("col");
System.out.println("Connect to database successfully");
mongoDatabase.createCollection("test");
System.out.println("集合创建成功");
} catch (Exception e) {
// TODO 自动生成的 catch 块
e.printStackTrace();
} finally {
if (mongoClient != null)
mongoClient.close();
}
}

// 插入文档数据
public static void insertMany() {
MongoClient mongoClient = null;
try {
// 连接到mongodb服务
mongoClient = new MongoClient("localhost", 27017);
// 连接到数据库
MongoDatabase mongoDatabase = mongoClient.getDatabase("col");
System.out.println("Connect to database successfully.");
MongoCollection<Document> collection = mongoDatabase.getCollection("test");
System.out.println("集合test选择成功!");
// 插入文档
// 1.创建文档org.bson.Document参数为key-value的格式
// 2.创建文档集合List<Document>
// 3.将文档集合插入数据库集合中mongoCollection.insertMany(List<Document>)
// 插入文档可以用mongoCollection.insertOne(Document)
Document document = new Document("title", "MongoDB").append("description", "database").append("likes", 100)
.append("by", "Fly");
List<Document> documents = new ArrayList<>();
documents.add(document);
collection.insertMany(documents);
System.out.println("文档插入成功");

} catch (Exception e) {
e.printStackTrace();
} finally {
if (mongoClient != null)
mongoClient.close();
}
}
//查询文档
public static void queryDocument() {
MongoClient mongoClient = null;
try {
// 连接到mongodb服务
mongoClient = new MongoClient();
// 连接到数据库
MongoDatabase mongoDatabase = mongoClient.getDatabase("col");
System.out.println("Connect to database successfully");
MongoCollection<Document> collection = mongoDatabase.getCollection("test");
System.out.println("选择集合test成功");
// 检索所有文档
// 1.获取迭代期FindIterable<Document>
// 2.获取游标MongoCursor<Document>
// 3.通过游标遍历检索出的文档集合
FindIterable<Document> findIterable = collection.find();
MongoCursor<Document> mongoCursor = findIterable.iterator();
while (mongoCursor.hasNext()) {
System.out.println(mongoCursor.next());
}
} catch (Exception e) {
e.printStackTrace();
} finally {
if (mongoClient != null)
mongoClient.close();
}
}

// 批量更新文档
public static void updateMany() {
MongoClient mongoClient = null;
try {
mongoClient = new MongoClient("localhost", 27017);
MongoDatabase mongoDatabase = mongoClient.getDatabase("col");
System.out.println("Connect to database successfully");
MongoCollection<Document> collection = mongoDatabase.getCollection("test");
System.out.println("集合test选择成功");
// 批量更新文档，将文档中likes=100文档修改为likes=200
collection.updateMany(Filters.eq("likes", 100), new Document("$set", new Document("likes", 200)));
// 检索查看结果
FindIterable<Document> findIterable = collection.find();
MongoCursor<Document> mongoCursor = findIterable.iterator();
while (mongoCursor.hasNext()) {
System.out.println(mongoCursor.next());
}
} catch (Exception e) {
// TODO 自动生成的 catch 块
e.printStackTrace();
} finally {
if (mongoClient != null)
mongoClient.close();
}
}
//删除第一个文档
public static void deleteOne() {
MongoClient mongoClient=null;
try {
mongoClient=new MongoClient("localhost",27017);
MongoDatabase mongoDatabase=mongoClient.getDatabase("col");
System.out.println("Connect to database successfully!");
MongoCollection<Document> collection=mongoDatabase.getCollection("test");
System.out.println("集合test选择成功");
//删除符合条件的第一个文档
collection.deleteOne(Filters.eq("likes", 200));
//删除所有符合条件的文档
collection.deleteMany(Filters.eq("likes", 200));
//检索查看结果
FindIterable<Document> findIterable=collection.find();
MongoCursor<Document> mongoCursor=findIterable.iterator();
while(mongoCursor.hasNext()) {
System.out.println(mongoCursor.next());
}
} catch (Exception e) {
e.printStackTrace();
}finally {
if(mongoClient!=null)
mongoClient.close();
}
}