Spring-boot访问MongoDB

package hello;

import org.springframework.context.annotation.Bean;
import org.springframework.context.annotation.Configuration;
import org.springframework.data.authentication.UserCredentials;
import org.springframework.data.mongodb.config.AbstractMongoConfiguration;
import org.springframework.data.mongodb.core.MongoOperations;
import org.springframework.data.mongodb.core.MongoTemplate;

import com.mongodb.Mongo;
import com.mongodb.MongoClient;

@Configuration
public class MongoConfig extends AbstractMongoConfiguration {
 
    @Bean
    public Mongo mongo() throws Exception {
        return new MongoClient();
    }
 
    @Bean
    public MongoTemplate mongoTemplate() throws Exception {
        UserCredentials user = new UserCredentials("scott", "tiger");
        return new MongoTemplate(mongo(), "test1", user);
    }

    @Override
    protected String getDatabaseName() {
        // TODO Auto-generated method stub
        return "test1";
    }
 
}

package hello;

import org.springframework.data.annotation.Id;


public class Customer {

    @Id
    private String id;

    private String firstName;
    private String lastName;

    public Customer() {}

    public Customer(String firstName, String lastName) {
        this.firstName = firstName;
        this.lastName = lastName;
    }

    @Override
    public String toString() {
        return String.format(
                "Customer[id=%s, firstName=‘%s‘, lastName=‘%s‘]",
                id, firstName, lastName);
    }

}

package hello;

import java.util.List;

import org.springframework.data.mongodb.repository.MongoRepository;

public interface CustomerRepository extends MongoRepository<Customer, String> {

    public Customer findByFirstName(String firstName);
    public List<Customer> findByLastName(String lastName);

}

package hello;

import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.boot.CommandLineRunner;
import org.springframework.boot.SpringApplication;
import org.springframework.boot.autoconfigure.AutoConfigureBefore;
import org.springframework.boot.autoconfigure.SpringBootApplication;
import org.springframework.context.annotation.Import;

@SpringBootApplication
@AutoConfigureBefore
@Import(MongoConfig.class)
public class Application implements CommandLineRunner {

    @Autowired
    private CustomerRepository repository;

    public static void main(String[] args) {
        SpringApplication.run(Application.class, args);
    }

    @Override
    public void run(String... args) throws Exception {

        repository.deleteAll();

        // save a couple of customers
        repository.save(new Customer("Alice", "Smith"));
        repository.save(new Customer("Bob", "Smith"));

        // fetch all customers
        System.out.println("Customers found with findAll():");
        System.out.println("-------------------------------");
        for (Customer customer : repository.findAll()) {
            System.out.println(customer);
        }
        System.out.println();

        // fetch an individual customer
        System.out.println("Customer found with findByFirstName(‘Alice‘):");
        System.out.println("--------------------------------");
        System.out.println(repository.findByFirstName("Alice"));

        System.out.println("Customers found with findByLastName(‘Smith‘):");
        System.out.println("--------------------------------");
        for (Customer customer : repository.findByLastName("Smith")) {
            System.out.println(customer);
        }

    }

}