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  • JAVA API从MongoDB中读取数据

        <dependency>
            <groupId>org.mongodb</groupId>
            <artifactId>mongodb-driver</artifactId>
            <version>3.2.2</version>
        </dependency>
    import java.util.ArrayList;  
    
    import org.bson.Document;
    import java.util.List;  
    import com.mongodb.MongoClient;  
    import com.mongodb.MongoCredential;  
    import com.mongodb.ServerAddress;
    import com.mongodb.client.MongoCollection;
    import com.mongodb.client.MongoCursor;
    import com.mongodb.client.MongoDatabase;  
    import com.mongodb.client.FindIterable;  
    
    public class MongodbAppHbaseTest {  
        public static void main(String[] args){  
            try {  
                //连接到MongoDB服务 如果是远程连接可以替换“localhost”为服务器所在IP地址  
                //ServerAddress()两个参数分别为 服务器地址 和 端口  
                ServerAddress serverAddress = new ServerAddress("1.1.1.1",27017);  
                List<ServerAddress> addrs = new ArrayList<ServerAddress>();  
                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("xxx", "xxx", "xxx".toCharArray());  
                List<MongoCredential> credentials = new ArrayList<MongoCredential>();  
                credentials.add(credential);  
                  
                //通过连接认证获取MongoDB连接  
                MongoClient mongoClient = new MongoClient(addrs, credentials);  
                  
                //连接到数据库  
                MongoDatabase mongoDatabase = mongoClient.getDatabase("name");  
                System.out.println("Connect to database successfully");  
                
    //            mongoDatabase.createCollection("xxx");
    //            System.out.println("集合创建成功");
                
                MongoCollection<Document> collection = mongoDatabase.getCollection("xxx");
                System.out.println("集合 xxx选择成功");
                
              //检索所有文档  
                /** 
                * 1. 获取迭代器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();
                int i=0;
                while(mongoCursor.hasNext()){  
                   System.out.println(mongoCursor.next());  
                   i++;
                }  
                System.out.println("i="+i);
                
            } catch (Exception e) {  
                System.err.println( e.getClass().getName() + ": " + e.getMessage() );  
            }  
        }  
    } 
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  • 原文地址:https://www.cnblogs.com/zhengchunhao/p/5684166.html
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