Spring Boot 自动配置中 JDBC Template 的自动装配数据源问题

16
我是Spring和J2EE的新手。我在使用Spring Boot自动配置时遇到了JDBC模板的问题。
我的做法是,我使用此处提供的RESTful Web服务示例,并决定扩展它以使用JDBC模板关系型数据库访问。不幸的是,此处提供的另一个示例无法使用,因为唯一的困难是未考虑从XML bean文件提供dataSource。
我尝试解决问题的方法如下:
1.使用DAO Impl类作为Spring中不同实现的扩展。 2.添加到bean文件中。 3.使用不同的DataSource类(例如DriverManagerDataSource)。 4.尝试仅在不同类中自动装配一个简单属性(比数据源更简单的内容)。 5.一开始我只写了DAO类,但后来我想到,如果它实现了接口,可能可以自动装配数据源,但没有帮助。
我尝试了Stack或Google上找到的所有方法。大多数示例严重过时、未被回答或与Spring Boot自动配置等无关。
我一直收到“需要属性'dataSource'”的错误提示,经过努力,我终于成功将“application-config.xml”文件与bean关联,但是无法自动连接JDBC的数据源。
我十分渴望完成它,但卡住了,没有思路。如果有人能提供一个最近的Spring Boot自动配置示例,XML中的bean查找,自动连接JDBC的数据源,那将不胜感激。
或者至少提供一些思路、线索,甚至如何搜索它的关键字,因为我甚至连关键词都用光了。
谢谢!

enter image description here

Spring应用程序类。

package ws;

import org.springframework.boot.autoconfigure.EnableAutoConfiguration;
import org.springframework.boot.SpringApplication;
import org.springframework.context.annotation.ComponentScan;
import org.springframework.context.annotation.Configuration;
import org.springframework.context.annotation.ImportResource;

@Configuration
@ComponentScan
@ImportResource("classpath:spring/application-config.xml")
@EnableAutoConfiguration
public class Application {

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

Web服务类。

package ws;

import dao.UserDAOImpl;
import model.User;
import org.springframework.web.bind.annotation.RequestMapping;
import org.springframework.web.bind.annotation.RequestParam;
import org.springframework.web.bind.annotation.RestController;

@RestController
public class TestWS {
    @RequestMapping("/greeting")
    public User greeting(@RequestParam(value="name", defaultValue="World") String name) {
    return new User("ubububu", "661331555", 0);
    }
    @RequestMapping("/create")
    public String initialize() {
        UserDAOImpl users = new UserDAOImpl();
        users.init();
        return "seems ok";
    }
}

DAO接口

package dao;

import model.User;

public interface UserDAO {
    public void insert(User usr);
    public void init();
    public User select(int id);
}

DAO实现

package dao;

import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.jdbc.core.JdbcTemplate;
import org.springframework.jdbc.datasource.DriverManagerDataSource;
import org.springframework.stereotype.Repository;

import model.User;
import dao.UserDAO;

@Repository
public class UserDAOImpl implements UserDAO {
    private JdbcTemplate jdbcTemplate;
    private DriverManagerDataSource dataSource;
    @Autowired
    public void setDataSource(DriverManagerDataSource dataSource) {
        this.dataSource = dataSource;
    }

    public void insert(User usr) {
        String sql = "INSERT INTO USER " +
                "(USR_ID, EMAIL, PHONE) VALUES (?, ?, ?)";

        this.jdbcTemplate = new JdbcTemplate(dataSource);
        jdbcTemplate.execute(sql);
    }

    public void init() {
        String sql = "CREATE TABLE USER (USR_ID INT(6) UNSIGNED AUTO_INCREMENT PRIMARY KEY,EMAIL VARCHAR(30) NOT NULL,PHONE VARCHAR(15) NOT NULL)";
        this.jdbcTemplate = new JdbcTemplate(dataSource);
        jdbcTemplate.execute(sql);
    }
}

数据模型
package model;

public class User {
    private String email;
    private String phone;
    private int id;
    public User(String email, String phone, int id) {
        this.email = email;
        this.phone = phone;
        this.id = id;
    }
    public int getUsrId(){
        return this.id;
    }
    public String getUsrEmail() {
        return this.email;
    }
    public String getUsrPhone() {
        return this.phone;
    }
}

配置bean文件

<?xml version="1.0" encoding="UTF-8"?>

<beans xmlns="http://www.springframework.org/schema/beans" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
    xmlns:context="http://www.springframework.org/schema/context"
    xsi:schemaLocation="http://www.springframework.org/schema/beans http://www.springframework.org/schema/beans/spring-beans.xsd
        http://www.springframework.org/schema/context http://www.springframework.org/schema/context/spring-context.xsd">
    <import resource="Spring-User.xml" />-->
    <context:component-scan base-package="ws"/>
    <bean id="ds" 
         class="org.springframework.jdbc.datasource.DriverManagerDataSource">

        <property name="driverClassName" value="org.springframework.jdbc.core.JdbcTemplate" />
        <property name="url" value="jdbc:mysql://localhost/:3306/databasename" />
        <property name="username" value="root" />
        <property name="password" value="password" />
    </bean>
    <bean id="UserDAOprovider" class="dao.UserDAOImpl">
        <property name="dataSource" ref="ds" />
    </bean> 

</beans>

错误信息:
ERROR [dispatcherServlet] - Servlet.service() for servlet [dispatcherServlet] in context with path [] threw exception [Request processing failed; nested exception is java.lang.IllegalArgumentException: Property 'dataSource' is required] with root cause
java.lang.IllegalArgumentException: Property 'dataSource' is required
    at org.springframework.jdbc.support.JdbcAccessor.afterPropertiesSet(JdbcAccessor.java:135) ~[spring-jdbc-4.0.8.RELEASE.jar!/:4.0.8.RELEASE]
    at org.springframework.jdbc.core.JdbcTemplate.<init>(JdbcTemplate.java:169) ~[spring-jdbc-4.0.8.RELEASE.jar!/:4.0.8.RELEASE]
    at dao.UserDAOImpl.init(UserDAOImpl.java:66) ~[demo3-0.0.1-SNAPSHOT.jar!/:na]
    at ws.TestWS.initialize(TestWS.java:30) ~[demo3-0.0.1-SNAPSHOT.jar!/:na]
    at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method) ~[na:1.6.0_33]
    at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:57) ~[na:1.6.0_33]
    at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43) ~[na:1.6.0_33]
    at java.lang.reflect.Method.invoke(Method.java:622) ~[na:1.6.0_33]
    at org.springframework.web.method.support.InvocableHandlerMethod.invoke(InvocableHandlerMethod.java:215) ~[spring-web-4.0.8.RELEASE.jar!/:4.0.8.RELEASE]
    at org.springframework.web.method.support.InvocableHandlerMethod.invokeForRequest(InvocableHandlerMethod.java:132) ~[spring-web-4.0.8.RELEASE.jar!/:4.0.8.RELEASE]
    at org.springframework.web.servlet.mvc.method.annotation.ServletInvocableHandlerMethod.invokeAndHandle(ServletInvocableHandlerMethod.java:104) ~[spring-webmvc-4.0.8.RELEASE.jar!/:4.0.8.RELEASE]
    at org.springframework.web.servlet.mvc.method.annotation.RequestMappingHandlerAdapter.invokeHandleMethod(RequestMappingHandlerAdapter.java:749) ~[spring-webmvc-4.0.8.RELEASE.jar!/:4.0.8.RELEASE]
    at org.springframework.web.servlet.mvc.method.annotation.RequestMappingHandlerAdapter.handleInternal(RequestMappingHandlerAdapter.java:689) ~[spring-webmvc-4.0.8.RELEASE.jar!/:4.0.8.RELEASE]
    at org.springframework.web.servlet.mvc.method.AbstractHandlerMethodAdapter.handle(AbstractHandlerMethodAdapter.java:83) ~[spring-webmvc-4.0.8.RELEASE.jar!/:4.0.8.RELEASE]
    at org.springframework.web.servlet.DispatcherServlet.doDispatch(DispatcherServlet.java:938) ~[spring-webmvc-4.0.8.RELEASE.jar!/:4.0.8.RELEASE]
    at org.springframework.web.servlet.DispatcherServlet.doService(DispatcherServlet.java:870) ~[spring-webmvc-4.0.8.RELEASE.jar!/:4.0.8.RELEASE]
    at org.springframework.web.servlet.FrameworkServlet.processRequest(FrameworkServlet.java:961) ~[spring-webmvc-4.0.8.RELEASE.jar!/:4.0.8.RELEASE]
    at org.springframework.web.servlet.FrameworkServlet.doGet(FrameworkServlet.java:852) ~[spring-webmvc-4.0.8.RELEASE.jar!/:4.0.8.RELEASE]
    at javax.servlet.http.HttpServlet.service(HttpServlet.java:620) ~[tomcat-embed-core-7.0.57.jar!/:7.0.57]
    at org.springframework.web.servlet.FrameworkServlet.service(FrameworkServlet.java:837) ~[spring-webmvc-4.0.8.RELEASE.jar!/:4.0.8.RELEASE]
    at javax.servlet.http.HttpServlet.service(HttpServlet.java:727) ~[tomcat-embed-core-7.0.57.jar!/:7.0.57]
    at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:303) ~[tomcat-embed-core-7.0.57.jar!/:7.0.57]
    at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:208) ~[tomcat-embed-core-7.0.57.jar!/:7.0.57]
    at org.springframework.web.filter.HiddenHttpMethodFilter.doFilterInternal(HiddenHttpMethodFilter.java:77) ~[spring-web-4.0.8.RELEASE.jar!/:4.0.8.RELEASE]
    at org.springframework.web.filter.OncePerRequestFilter.doFilter(OncePerRequestFilter.java:107) ~[spring-web-4.0.8.RELEASE.jar!/:4.0.8.RELEASE]
    at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:241) ~[tomcat-embed-core-7.0.57.jar!/:7.0.57]
    at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:208) ~[tomcat-embed-core-7.0.57.jar!/:7.0.57]
    at org.apache.catalina.core.StandardWrapperValve.invoke(StandardWrapperValve.java:220) ~[tomcat-embed-core-7.0.57.jar!/:7.0.57]
    at org.apache.catalina.core.StandardContextValve.invoke(StandardContextValve.java:122) ~[tomcat-embed-core-7.0.57.jar!/:7.0.57]
    at org.apache.catalina.authenticator.AuthenticatorBase.invoke(AuthenticatorBase.java:503) ~[tomcat-embed-core-7.0.57.jar!/:7.0.57]
    at org.apache.catalina.core.StandardHostValve.invoke(StandardHostValve.java:170) ~[tomcat-embed-core-7.0.57.jar!/:7.0.57]
    at org.apache.catalina.valves.ErrorReportValve.invoke(ErrorReportValve.java:103) ~[tomcat-embed-core-7.0.57.jar!/:7.0.57]
    at org.apache.catalina.core.StandardEngineValve.invoke(StandardEngineValve.java:116) ~[tomcat-embed-core-7.0.57.jar!/:7.0.57]
    at org.apache.catalina.connector.CoyoteAdapter.service(CoyoteAdapter.java:421) ~[tomcat-embed-core-7.0.57.jar!/:7.0.57]
    at org.apache.coyote.http11.AbstractHttp11Processor.process(AbstractHttp11Processor.java:1070) ~[tomcat-embed-core-7.0.57.jar!/:7.0.57]
    at org.apache.coyote.AbstractProtocol$AbstractConnectionHandler.process(AbstractProtocol.java:611) ~[tomcat-embed-core-7.0.57.jar!/:7.0.57]
    at org.apache.tomcat.util.net.NioEndpoint$SocketProcessor.doRun(NioEndpoint.java:1736) ~[tomcat-embed-core-7.0.57.jar!/:7.0.57]
    at org.apache.tomcat.util.net.NioEndpoint$SocketProcessor.run(NioEndpoint.java:1695) ~[tomcat-embed-core-7.0.57.jar!/:7.0.57]
    at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1146) ~[na:1.6.0_33]
    at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:615) ~[na:1.6.0_33]
    at org.apache.tomcat.util.threads.TaskThread$WrappingRunnable.run(TaskThread.java:61) ~[tomcat-embed-core-7.0.57.jar!/:7.0.57]
    at java.lang.Thread.run(Thread.java:701) ~[na:1.6.0_33]
1个回答

32

在Spring Boot中配置数据源的最简单方式是创建一个名为application.properties的文件,放置在src/main/resources目录下,并包含以下内容(可能需要更新具体的url、用户名和密码):

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

Spring Boot会自动为您创建DataSource类并将其注入到其他bean中。由此,您将不再需要使用xml配置文件,并可以在Application类中删除此行:

@ImportResource("classpath:spring/application-config.xml")

此外,在UserDAOImpl中,Spring可以使用DataSource bean自动装配JdbcTemplate对象(http://docs.spring.io/spring-boot/docs/current/reference/html/boot-features-sql.html#boot-features-using-jdbc-template),这样每次调用insert()方法时就不需要创建一个新的了。

至于UserDAOImpl中的init()方法,您可以在src/main/resources下创建一个schema.sql文件,并将CREATE TABLE语句移动到那里(有关更多详细信息,请参见http://docs.spring.io/spring-boot/docs/1.2.0.RELEASE/reference/htmlsingle/#howto-intialize-a-database-using-spring-jdbc

有关更多信息,请参见以下示例:http://xantorohara.blogspot.ca/2013/11/spring-boot-jdbc-sample.html


感谢kaviddiss的回答。我刚刚在src/main/resources下创建了application.properties文件,但不幸的是,我仍然收到相同的错误消息。我还尝试将其放在src/main/resources/spring目录下,但结果相同。您确定驱动程序包必须是com.mysql.jdbc.Driver吗? - Marek
你收到了什么错误信息?驱动程序类名是特定于你正在使用的数据库。如果是mysql,则属性文件中的值应为com.mysql.jdbc.Driver。 - kaviddiss
这是mysql,在这种情况下驱动程序是正确的。堆栈消息太长无法在评论中发布,因此我编辑了问题并将其添加到末尾。再次感谢! - Marek
你能否尝试在UserDAOImpl的setDataSource()方法中将DriverManagerDataSource更改为DataSource? - kaviddiss
3
请查看以下链接获取帮助:http://xantorohara.blogspot.ca/2013/11/spring-boot-jdbc-sample.html 和 http://blog.netgloo.com/2014/10/27/using-mysql-in-spring-boot-via-spring-data-jpa-and-hibernate/。 - kaviddiss
显示剩余6条评论

网页内容由stack overflow 提供, 点击上面的
可以查看英文原文,
原文链接