在Java应用程序中操作 MongoDB 数据
1. 启动MongoDB Shell
2. 切换到admin数据库,使用root账户
3.开启Eclipse,创建Java Project项目,命名为MongoJava
File --> New --> Java Project
4.在MongoJava项目下新建包,包名为mongo
MongoJava右键 --> New --> mongo
5. 在mongo包下新建类,类名为mimalianjie
mongo右键 --> New --> Class
6. 添加项目依赖的jar包,右键单击MongoJava,选择Import
7. 选择General中的File System,点击Next
8. 选择存放mongo连接java的驱动程序的文件夹,并进行勾选Create top-level folder
9. 选中导入的文件夹中的mongo-java-driver-3.2.2.jar,右击选择Build Path中的Add to Build Path。
10. 连接数据库:编写代码,功能为连接Mongodb数据库。我们需要指定数据库名称,如果指定的数据库不存在,mongo会自动创建数据库
package mongo;
import java.util.ArrayList;
import com.mongodb.MongoClient;
import com.mongodb.MongoCredential;
import com.mongodb.ServerAddress;
import com.mongodb.client.MongoDatabase;
public class mimalianjie {
public static void main(String[] args) {
try {
ServerAddress serverAddress = new ServerAddress("localhost",27017);
ArrayList<ServerAddress> addrs = new ArrayList<ServerAddress>();
addrs.add(serverAddress);
MongoCredential credential = MongoCredential.createScramSha1Credential("root", "admin", "strongs".toCharArray());
ArrayList<MongoCredential> credentials = new
ArrayList<MongoCredential>();
credentials.add(credential);
MongoClient mongoClient = new MongoClient(addrs,credentials);
MongoDatabase mongoDatabase = mongoClient.getDatabase("databaseName");
System.out.println("Connect to database successfully");
} catch (Exception e) {
System.err.println( e.getClass().getName() + ": " + e.getMessage() );
}
}
}
11. 创建集合:与上述步骤相同,在mongo包下新建类,类名为chuangjianjihe,编写代码,功能为在test库下创建集合mycol(使用com.mongodb.client.MongoDatabase类中的createCollection()来创建集合)
package mongo;
import java.util.ArrayList;
import com.mongodb.MongoClient;
import com.mongodb.MongoCredential;
import com.mongodb.ServerAddress;
import com.mongodb.client.MongoDatabase;
public class chuanjianjihe {
public static void main(String[] args) {
try {
ServerAddress serverAddress = new ServerAddress("localhost",27017);
ArrayList<ServerAddress> addrs = new ArrayList<ServerAddress>();
addrs.add(serverAddress);
MongoCredential credential = MongoCredential.createScramSha1Credential("root","admin","strongs".toCharArray());
ArrayList<MongoCredential> credentials = new ArrayList<MongoCredential>();
credentials.add(credential);
MongoClient mongoClient = new MongoClient(addrs,credentials);
MongoDatabase mongoDatabase = mongoClient.getDatabase("test");
System.out.println("Connect to database successfully");
mongoDatabase.createCollection("mycol");
System.out.println("集合mycol创建成功");
}catch (Exception e) {
System.err.println( e.getClass().getName() + ": " + e.getMessage());
}
}
}
12. 在mongodb中进行验证
13. 获取集合:在mongo包下新建类,名为huoqujihe,并编写代码,功能为获取所需集合(使用com.mongodb.client.MongoDatabase类的 getCollection() 方法来获取一个集合)
package mongo;
import java.util.ArrayList;
import com.mongodb.MongoClient;
import com.mongodb.MongoCredential;
import com.mongodb.ServerAddress;
import com.mongodb.client.MongoCollection;
import com.mongodb.client.MongoDatabase;
public class huoqujihe {
public static void main(String[] args) {
try {
ServerAddress serverAddress = new ServerAddress("localhost",27017);
ArrayList<ServerAddress> addrs = new ArrayList<ServerAddress>();
addrs.add(serverAddress);
MongoCredential credential = MongoCredential.createScramSha1Credential("root","admin","strongs".toCharArray());
ArrayList<MongoCredential> credentials = new ArrayList<MongoCredential>();
credentials.add(credential);
MongoClient mongoClient = new MongoClient(addrs,credentials);
MongoDatabase mongoDatabase = mongoClient.getDatabase("test");
System.out.println("Connect to database successfully");
MongoCollection<org.bson.Document> collection = mongoDatabase.getCollection("mycol");
System.out.println("集合mycol选择成功");
} catch (Exception e) {
System.err.println( e.getClass().getName() + ": " + e.getMessage());
}
}
}
14.插入文档:在mongo包中新建类,名为charuwendang,功能为连接test库,选择mycol集合并向其中插入文档。(使用com.mongodb.client.MongoCollection类的insertMany()方法来插入一个文档)
package mongo;
import java.util.ArrayList;
import java.util.List;
import org.bson.Document;
import com.mongodb.MongoClient;
import com.mongodb.MongoCredential;
import com.mongodb.ServerAddress;
import com.mongodb.client.MongoCollection;
import com.mongodb.client.MongoDatabase;
public class charuwendang {
public static void main (String[] args) {
try {
ServerAddress serverAddress = new ServerAddress("localhost",27017);
ArrayList<ServerAddress> addrs = new ArrayList<ServerAddress>();
addrs.add(serverAddress);
MongoCredential credential = MongoCredential.createScramSha1Credential("root"
,"admin","strongs".toCharArray());
ArrayList<MongoCredential> credentials = new ArrayList<MongoCredential>();
credentials.add(credential);
MongoClient mongoClient = new MongoClient(addrs,credentials);
MongoDatabase mongoDatabase = mongoClient.getDatabase("test");
System.out.println("Connect to database successfully");
MongoCollection<org.bson.Document> collection = mongoDatabase.getCollection("mycol");
System.out.println("集合mycol选择成功");
Document document = new Document("name", "zhangyudashuju").
append("description", "YXCX").
append("likes", 100).
append("location", "BJ");
List<Document> documents = new ArrayList<Document>();
documents.add(document);
collection.insertMany(documents);
System.out.println("文档插入成功");
}catch(Exception e) {
System.err.println( e.getClass().getName() + ": " + e.getMessage() );
}
}
}
15.在mongodb中进行查询验证
16. 检索文档:在mongo包中新建类,名为jiansuosuoyouwendang,功能为检索test库下,mycol集合中的所有文档(使用 com.mongodb.client.MongoCollection 类中的 find() 方法来获取集合中的所有文档)
package mongo;
import java.util.ArrayList;
import org.bson.Document;
import com.mongodb.MongoClient;
import com.mongodb.MongoCredential;
import com.mongodb.ServerAddress;
import com.mongodb.client.FindIterable;
import com.mongodb.client.MongoCollection;
import com.mongodb.client.MongoCursor;
import com.mongodb.client.MongoDatabase;
public class jiansuosuoyouwendang {
public static void main( String args[] ){
try{
ServerAddress serverAddress = new ServerAddress("localhost",27017);
ArrayList<ServerAddress> addrs = new ArrayList<ServerAddress>();
addrs.add(serverAddress);
MongoCredential credential = MongoCredential.createScramSha1Credential("root"
,"admin", "strongs".toCharArray());
ArrayList<MongoCredential> credentials = new ArrayList<MongoCredential>();
credentials.add(credential);
MongoClient mongoClient = new MongoClient(addrs,credentials);
MongoDatabase mongoDatabase = mongoClient.getDatabase("test");
System.out.println("Connect to database successfully");
MongoCollection<org.bson.Document> collection = mongoDatabase.getCollection("mycol");
System.out.println("集合mycol选择成功");
FindIterable<Document> findIterable = collection.find();
MongoCursor<Document> mongoCursor = findIterable.iterator();
while(mongoCursor.hasNext()){
System.out.println(mongoCursor.next());
}
}catch(Exception e){
System.err.println( e.getClass().getName() + ": " + e.getMessage() );
}
}
}
17. 更新文档:在mongo包中新建类,名为gengxinwendang,功能为选择test库下mycol集合,将文档中的likes=100改为likes=200(使用 com.mongodb.client.MongoCollection 类中的updateMany()方法来更新集合中的文档)
package mongo;
import java.util.ArrayList;
import org.bson.Document;
import com.mongodb.MongoClient;
import com.mongodb.MongoCredential;
import com.mongodb.ServerAddress;
import com.mongodb.client.FindIterable;
import com.mongodb.client.MongoCollection;
import com.mongodb.client.MongoCursor;
import com.mongodb.client.MongoDatabase;
import com.mongodb.client.model.Filters;
public class gengxinwendang {
public static void main( String args[] ){
try{
ServerAddress serverAddress = new ServerAddress("localhost",27017);
ArrayList<ServerAddress> addrs = new ArrayList<ServerAddress>();
addrs.add(serverAddress);
MongoCredential credential = MongoCredential.createScramSha1Credential("root"
,"admin", "strongs".toCharArray());
ArrayList<MongoCredential> credentials = new ArrayList<MongoCredential>();
credentials.add(credential);
MongoClient mongoClient = new MongoClient(addrs,credentials);
MongoDatabase mongoDatabase = mongoClient.getDatabase("test");
System.out.println("Connect to database successfully");
MongoCollection<org.bson.Document> collection = mongoDatabase.getCollection("mycol");
System.out.println("集合mycol选择成功");
collection.updateMany(Filters.eq("likes", 100), new Document("$set",new Document("likes",200)));
FindIterable<Document> findIterable = collection.find();
MongoCursor<Document> mongoCursor = findIterable.iterator();
while(mongoCursor.hasNext()){
System.out.println(mongoCursor.next());
}
}catch(Exception e){
System.err.println( e.getClass().getName() + ": " + e.getMessage() );
}
}
}
18. 在mongodb中进行查询验证
19. 删除文档:在mongo包中新建类,名为sanchuwendang,功能为选择test库下mycol集合,删除所有符合条件(likes=200)的文档。(使用com.mongodb.DBCollection类中的findOne()方法来获取第一个文档,然后使用remove方法删除)
package mongo;
import java.util.ArrayList;
import org.bson.Document;
import com.mongodb.MongoClient;
import com.mongodb.MongoCredential;
import com.mongodb.ServerAddress;
import com.mongodb.client.FindIterable;
import com.mongodb.client.MongoCollection;
import com.mongodb.client.MongoCursor;
import com.mongodb.client.MongoDatabase;
import com.mongodb.client.model.Filters;
public class shanchuwendang {
public static void main( String args[] ){
try{
ServerAddress serverAddress = new ServerAddress("localhost",27017);
ArrayList<ServerAddress> addrs = new ArrayList<ServerAddress>();
addrs.add(serverAddress);
MongoCredential credential = MongoCredential.createScramSha1Credential("root"
,"admin", "strongs".toCharArray());
ArrayList<MongoCredential> credentials = new ArrayList<MongoCredential>();
credentials.add(credential);
MongoClient mongoClient = new MongoClient(addrs,credentials);
MongoDatabase mongoDatabase = mongoClient.getDatabase("test");
System.out.println("Connect to database successfully");
MongoCollection<org.bson.Document> collection = mongoDatabase.getCollection("mycol");
System.out.println("集合mycol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){
System.err.println( e.getClass().getName() + ": " + e.getMessage() );
}
}
}
20. 在mongodb中进行查询验证
查询结果为空,证明文档已被删除。
至此,实验结束!