Basit bir MySql veritabanına bağlanmak için Spring'in JdbcTemplate'i nasıl kullanılır?

Question

this eğiticisini temel alan basit bir MySql veritabanına bağlanmak için Spring'in JdbcTemplate Sınıfını kullanmaya çalışıyorum. Lombok bağımlılık Alıcı ve ayarlayıcıların içindir

pom.xml

<project xmlns="http://maven.apache.org/POM/4.0.0" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" 
    xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 http://maven.apache.org/xsd/maven-4.0.0.xsd"> 
    <modelVersion>4.0.0</modelVersion> 
    <groupId>test</groupId> 
    <artifactId>jdbc-test</artifactId> 
    <version>0.0.1-SNAPSHOT</version> 

    <parent> 
     <groupId>org.springframework.boot</groupId> 
     <artifactId>spring-boot-starter-parent</artifactId> 
     <version>1.2.2.RELEASE</version> 
    </parent> 

    <dependencies> 
     <dependency> 
      <groupId>org.springframework.boot</groupId> 
      <artifactId>spring-boot-starter</artifactId> 
     </dependency> 
     <dependency> 
      <groupId>org.springframework</groupId> 
      <artifactId>spring-jdbc</artifactId> 
     </dependency> 
     <dependency> 
      <groupId>mysql</groupId> 
      <artifactId>mysql-connector-java</artifactId> 
     </dependency> 
     <dependency> 
      <groupId>org.projectlombok</groupId> 
      <artifactId>lombok</artifactId> 
      <version>1.14.8</version> 
      <scope>provided</scope> 
     </dependency> 
    </dependencies> 
    <build> 
     <plugins> 
      <plugin> 
       <groupId>org.springframework.boot</groupId> 
       <artifactId>spring-boot-maven-plugin</artifactId> 
      </plugin> 
     </plugins> 
    </build> 
</project> 

: Aslında onların proje kurulum kullandı.

package test; 

import org.springframework.beans.factory.annotation.Autowired; 
import org.springframework.boot.CommandLineRunner; 
import org.springframework.boot.SpringApplication; 
import org.springframework.boot.autoconfigure.SpringBootApplication; 
import org.springframework.jdbc.core.JdbcTemplate; 

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

    @Autowired 
    JdbcTemplate jdbcTemplate; 

    @Override 
    public void run(String... arg0) throws Exception { 
     System.out.println("Creating tables"); 
     jdbcTemplate.execute("drop table customers if exists"); 
     jdbcTemplate.execute("create table customers(" + 
       "id serial, first_name varchar(255), last_name varchar(255))"); 
    } 
} 

Ve nihayet bir müşteri pojo:

Sonra Uygulama sınıfı yoktur

benim kaynakları klasörde bir application.properties dosyası var veri kaynağı yapılandırma için

package test; 

import lombok.AllArgsConstructor; 
import lombok.Data; 

@Data 
@AllArgsConstructor 
public class Customer { 
    private long id; 
    private String firstName, lastName; 
} 

:

spring.datasource.url=jdbc:mysql://localhost:3306/test 
spring.datasource.username=test 
spring.datasource.password=test 
spring.datasource.driver-class-name=com.mysql.jdbc.Driver 

spring.jpa.database = MYSQL 

spring.jpa.show-sql = true 

spring.jpa.hibernate.ddl-auto = update 
spring.jpa.hibernate.dialect = org.hibernate.dialect.MySQL5Dialect 
spring.jpa.hibernate.naming_strategy = org.hibernate.cfg.ImprovedNamingStrategy 

Veritabanı çalışıyor ve çalışıyor ve hala autowirig dont görünmüyor iş. Ne Tuhaf Bir com.h2database ile mysql-connector-java dependeny değiştirirseniz, sadece çalışan gerçeği

org.springframework.beans.factory.BeanCreationException: Error creating bean with name 'application': Injection of autowired dependencies failed; nested exception is org.springframework.beans.factory. 
BeanCreationException: Could not autowire field: org.springframework.jdbc.core.JdbcTemplate test.Application.jdbcTemplate; nested exception is org.springframework.beans.factory.NoSuchBeanDefinitionException: 
No qualifying bean of type [org.springframework.jdbc.core.JdbcTemplate] found for dependency: expected at least 1 bean which qualifies as autowire candidate for this dependency. Dependency annotations: 
{@org.springframework.beans.factory.annotation.Autowired(required=true)} 
     at org.springframework.beans.factory.annotation.AutowiredAnnotationBeanPostProcessor.postProcessPropertyValues(AutowiredAnnotationBeanPostProcessor.java:334) 
     at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.populateBean(AbstractAutowireCapableBeanFactory.java:1202) 
     at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.doCreateBean(AbstractAutowireCapableBeanFactory.java:537) 
     at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.createBean(AbstractAutowireCapableBeanFactory.java:476) 
     at org.springframework.beans.factory.support.AbstractBeanFactory$1.getObject(AbstractBeanFactory.java:303) 
     at org.springframework.beans.factory.support.DefaultSingletonBeanRegistry.getSingleton(DefaultSingletonBeanRegistry.java:230) 
     at org.springframework.beans.factory.support.AbstractBeanFactory.doGetBean(AbstractBeanFactory.java:299) 
     at org.springframework.beans.factory.support.AbstractBeanFactory.getBean(AbstractBeanFactory.java:194) 
     at org.springframework.beans.factory.support.DefaultListableBeanFactory.preInstantiateSingletons(DefaultListableBeanFactory.java:755) 
     at org.springframework.context.support.AbstractApplicationContext.finishBeanFactoryInitialization(AbstractApplicationContext.java:757) 
     at org.springframework.context.support.AbstractApplicationContext.refresh(AbstractApplicationContext.java:480) 
     at org.springframework.boot.SpringApplication.refresh(SpringApplication.java:686) 
     at org.springframework.boot.SpringApplication.run(SpringApplication.java:320) 
     at org.springframework.boot.SpringApplication.run(SpringApplication.java:957) 
     at org.springframework.boot.SpringApplication.run(SpringApplication.java:946) 
     at test.Application.main(Application.java:12) 
     at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method) 
     at sun.reflect.NativeMethodAccessorImpl.invoke(Unknown Source) 
     at sun.reflect.DelegatingMethodAccessorImpl.invoke(Unknown Source) 
     at java.lang.reflect.Method.invoke(Unknown Source) 
     at org.springframework.boot.loader.MainMethodRunner.run(MainMethodRunner.java:53) 
     at java.lang.Thread.run(Unknown Source) 
Caused by: org.springframework.beans.factory.BeanCreationException: Could not autowire field: org.springframework.jdbc.core.JdbcTemplate test.Application.jdbcTemplate; nested exception is org.springframework.beans.factory.NoSuchBeanDefinitionException: 
No qualifying bean of type [org.springframework.jdbc.core.JdbcTemplate] found for dependency: expected at least 1 bean which qualifies as autowire 
candidate for this dependency. Dependency annotations: {@org.springframework.beans.factory.annotation.Autowired(required=true)} 
     at org.springframework.beans.factory.annotation.AutowiredAnnotationBeanPostProcessor$AutowiredFieldElement.inject(AutowiredAnnotationBeanPostProcessor.java:561) 
     at org.springframework.beans.factory.annotation.InjectionMetadata.inject(InjectionMetadata.java:88) 
     at org.springframework.beans.factory.annotation.AutowiredAnnotationBeanPostProcessor.postProcessPropertyValues(AutowiredAnnotationBeanPostProcessor.java:331) 
     ... 21 common frames omitted 
Caused by: org.springframework.beans.factory.NoSuchBeanDefinitionException: No qualifying bean of type [org.springframework.jdbc.core.JdbcTemplate] found for dependency: expected at least 1 bean which 
qualifies as autowire candidate for this dependency. Dependency annotations: {@org.springframework.beans.factory.annotation.Autowired(required=true)} 
     at org.springframework.beans.factory.support.DefaultListableBeanFactory.raiseNoSuchBeanDefinitionException(DefaultListableBeanFactory.java:1301) 
     at org.springframework.beans.factory.support.DefaultListableBeanFactory.doResolveDependency(DefaultListableBeanFactory.java:1047) 
     at org.springframework.beans.factory.support.DefaultListableBeanFactory.resolveDependency(DefaultListableBeanFactory.java:942) 
     at org.springframework.beans.factory.annotation.AutowiredAnnotationBeanPostProcessor$AutowiredFieldElement.inject(AutowiredAnnotationBeanPostProcessor.java:533) 
     ... 23 common frames omitted 

(as: Ben çalıştırmayı denediğinizde İşte alıyorum istisna bahar örneğinde).

Mysql veri kaynağını direktif olarak yapılandırmalı mıyım? Herhangi bir öneriniz var mı?

<dependency> 
    <groupId>org.springframework.boot</groupId> 
     <artifactId>spring-boot-starter-jdbc</artifactId> 
</dependency> 

, Datasource'u

Answer 1

aşağıda bağımlılık ekleyin. Önyükleme uygulamanızı çalıştırdığınızda ve günlüklere baktığınızda `--debug`` java` argümanını ekleyin.