java - com.mysql.jdbc.exceptions.jdbc4.CommunicationsException : Communications link failure AND BeanEntityManager error-6ren

java - com.mysql.jdbc.exceptions.jdbc4.CommunicationsException : Communications link failure AND BeanEntityManager error

转载作者：可可西里更新时间：2023-11-01 08:38:55

由于第一个错误消息包含很多字符，因此不得不将其删减很多，但可以在此处找到完整的内容:https://github.com/kableiv/FullSpringError

一些背景故事:完成一项任务并需要创建一个小型网站，其中 2 个预定义用户可以登录，一个具有用户权限，一个具有管理员权限，这些权限是将您重定向到您编辑、删除和注册新信息的页面的按钮。起初我没有使用 spring security 也没有数据库，使用数组列表和文件。当我以用户身份登录时，它仅具有应有的用户权限，但是当我以管理员身份登录然后进入任何其他 html 页面时，例如用于编辑内容的页面，然后单击返回按钮，管理员权限消失了。我假设这是因为我在我的登录方法中将其管理值设置为 true(因此 html 页面知道要显示什么和不显示什么)然后当该方法完成并且新方法开始时就像编辑方法一样该值已恢复为空。

因此，我决定尝试改用具有 Spring Security 的 MySQL 数据库。我选择的 IDE 是 intellij ultimate，我使用 MySQL Workbench 设置数据库并使用数据库功能将其添加到 intellij 中。

现在，当尝试运行该项目时，出现以下错误:

2018-05-04 16:59:10.780  INFO 8364 --- [           main] com.rfboernehave.demo.DemoApplication    : Starting DemoApplication on DESKTOP-QB8IIQF with PID 8364 (C:\Users\nerdi\SpringbootWebAppMiniproject1\target\classes started by nerdi in C:\Users\nerdi\SpringbootWebAppMiniproject1)
2018-05-04 16:59:10.783  INFO 8364 --- [           main] com.rfboernehave.demo.DemoApplication    : No active profile set, falling back to default profiles: default
2018-05-04 16:59:11.390  INFO 8364 --- [           main] ationConfigEmbeddedWebApplicationContext : Refreshing org.springframework.boot.context.embedded.AnnotationConfigEmbeddedWebApplicationContext@516be40f: startup date [Fri May 04 16:59:11 CEST 2018]; root of context hierarchy
2018-05-04 16:59:14.723  INFO 8364 --- [           main] s.b.c.e.t.TomcatEmbeddedServletContainer : Tomcat initialized with port(s): 5000 (http)
2018-05-04 16:59:14.747  INFO 8364 --- [           main] o.apache.catalina.core.StandardService   : Starting service [Tomcat]
2018-05-04 16:59:14.747  INFO 8364 --- [           main] org.apache.catalina.core.StandardEngine  : Starting Servlet Engine: Apache Tomcat/8.5.16
2018-05-04 16:59:15.021  INFO 8364 --- [ost-startStop-1] o.a.c.c.C.[Tomcat].[localhost].[/]       : Initializing Spring embedded WebApplicationContext
2018-05-04 16:59:15.021  INFO 8364 --- [ost-startStop-1] o.s.web.context.ContextLoader            : Root WebApplicationContext: initialization completed in 3638 ms
2018-05-04 16:59:15.343  INFO 8364 --- [ost-startStop-1] o.s.b.w.servlet.FilterRegistrationBean   : Mapping filter: 'characterEncodingFilter' to: [/*]
2018-05-04 16:59:15.343  INFO 8364 --- [ost-startStop-1] o.s.b.w.servlet.FilterRegistrationBean   : Mapping filter: 'hiddenHttpMethodFilter' to: [/*]
2018-05-04 16:59:15.343  INFO 8364 --- [ost-startStop-1] o.s.b.w.servlet.FilterRegistrationBean   : Mapping filter: 'httpPutFormContentFilter' to: [/*]
2018-05-04 16:59:15.343  INFO 8364 --- [ost-startStop-1] o.s.b.w.servlet.FilterRegistrationBean   : Mapping filter: 'requestContextFilter' to: [/*]
2018-05-04 16:59:15.343  INFO 8364 --- [ost-startStop-1] .s.DelegatingFilterProxyRegistrationBean : Mapping filter: 'springSecurityFilterChain' to: [/*]
2018-05-04 16:59:15.347  INFO 8364 --- [ost-startStop-1] o.s.b.w.servlet.ServletRegistrationBean  : Mapping servlet: 'dispatcherServlet' to [/]
2018-05-04 16:59:18.235 ERROR 8364 --- [           main] o.a.tomcat.jdbc.pool.ConnectionPool      : Unable to create initial connections of pool.

com.mysql.jdbc.exceptions.jdbc4.CommunicationsException: Communications link failure

The last packet sent successfully to the server was 0 milliseconds ago. The driver has not received any packets from the server.
at com.mysql.jdbc.Util.handleNewInstance(Util.java:425) ~[mysql-connector-java-5.1.43.jar:5.1.43]
    at com.mysql.jdbc.SQLError.createCommunicationsException(SQLError.java:989) ~[mysql-connector-java-5.1.43.jar:5.1.43]
    at com.mysql.jdbc.MysqlIO.<init>(MysqlIO.java:341) ~[mysql-connector-java-5.1.43.jar:5.1.43]
    at com.mysql.jdbc.ConnectionImpl.coreConnect(ConnectionImpl.java:2196) ~[mysql-connector-java-5.1.43.jar:5.1.43]
    at com.mysql.jdbc.ConnectionImpl.connectOneTryOnly(ConnectionImpl.java:2229) ~[mysql-connector-java-5.1.43.jar:5.1.43]
    at com.mysql.jdbc.ConnectionImpl.createNewIO(ConnectionImpl.java:2024) ~[mysql-connector-java-5.1.43.jar:5.1.43]
    at com.mysql.jdbc.ConnectionImpl.<init>(ConnectionImpl.java:779) ~[mysql-connector-java-5.1.43.jar:5.1.43]

at com.mysql.jdbc.JDBC4Connection.<init>(JDBC4Connection.java:47) ~[mysql-connector-java-5.1.43.jar:5.1.43]
at com.mysql.jdbc.Util.handleNewInstance(Util.java:425) ~[mysql-connector-java-5.1.43.jar:5.1.43]
    at com.mysql.jdbc.ConnectionImpl.getInstance(ConnectionImpl.java:389) ~[mysql-connector-java-5.1.43.jar:5.1.43]
    at com.mysql.jdbc.NonRegisteringDriver.connect(NonRegisteringDriver.java:330) ~[mysql-connector-java-5.1.43.jar:5.1.43]
    at org.apache.tomcat.jdbc.pool.PooledConnection.connectUsingDriver(PooledConnection.java:310) ~[tomcat-jdbc-8.5.16.jar:na]
    at org.apache.tomcat.jdbc.pool.PooledConnection.connect(PooledConnection.java:203) ~[tomcat-jdbc-8.5.16.jar:na]
    at org.apache.tomcat.jdbc.pool.ConnectionPool.createConnection(ConnectionPool.java:735) [tomcat-jdbc-8.5.16.jar:na]
    at org.apache.tomcat.jdbc.pool.ConnectionPool.borrowConnection(ConnectionPool.java:667) [tomcat-jdbc-8.5.16.jar:na]
    at org.apache.tomcat.jdbc.pool.ConnectionPool.init(ConnectionPool.java:482) [tomcat-jdbc-8.5.16.jar:na]
    at org.apache.tomcat.jdbc.pool.ConnectionPool.<init>(ConnectionPool.java:154) [tomcat-jdbc-8.5.16.jar:na]
    at org.apache.tomcat.jdbc.pool.DataSourceProxy.pCreatePool(DataSourceProxy.java:118) [tomcat-jdbc-8.5.16.jar:na]
    at org.apache.tomcat.jdbc.pool.DataSourceProxy.createPool(DataSourceProxy.java:107) [tomcat-jdbc-8.5.16.jar:na]
    at org.apache.tomcat.jdbc.pool.DataSourceProxy.getConnection(DataSourceProxy.java:131) [tomcat-jdbc-8.5.16.jar:na]
    at org.springframework.jdbc.datasource.DataSourceUtils.doGetConnection(DataSourceUtils.java:111) [spring-jdbc-4.3.10.RELEASE.jar:4.3.10.RELEASE]
    at org.springframework.jdbc.datasource.DataSourceUtils.getConnection(DataSourceUtils.java:77) [spring-jdbc-4.3.10.RELEASE.jar:4.3.10.RELEASE]
    at org.springframework.jdbc.support.JdbcUtils.extractDatabaseMetaData(JdbcUtils.java:326) [spring-jdbc-4.3.10.RELEASE.jar:4.3.10.RELEASE]
    at org.springframework.jdbc.support.JdbcUtils.extractDatabaseMetaData(JdbcUtils.java:366) [spring-jdbc-4.3.10.RELEASE.jar:4.3.10.RELEASE]
    at org.springframework.boot.autoconfigure.orm.jpa.DatabaseLookup.getDatabase(DatabaseLookup.java:72) [spring-boot-autoconfigure-1.5.6.RELEASE.jar:1.5.6.RELEASE]
    at org.springframework.boot.autoconfigure.orm.jpa.JpaProperties.determineDatabase(JpaProperties.java:139) [spring-boot-autoconfigure-1.5.6.RELEASE.jar:1.5.6.RELEASE]
    at org.springframework.boot.autoconfigure.orm.jpa.JpaBaseConfiguration.jpaVendorAdapter(JpaBaseConfiguration.java:105) [spring-boot-autoconfigure-1.5.6.RELEASE.jar:1.5.6.RELEASE]
    at org.springframework.boot.autoconfigure.orm.jpa.HibernateJpaAutoConfiguration$$EnhancerBySpringCGLIB$$e4aac97b.CGLIB$jpaVendorAdapter$5(<generated>) [spring-boot-autoconfigure-1.5.6.RELEASE.jar:1.5.6.RELEASE]
    at org.springframework.boot.autoconfigure.orm.jpa.HibernateJpaAutoConfiguration$$EnhancerBySpringCGLIB$$e4aac97b$$FastClassBySpringCGLIB$$6844864e.invoke(<generated>) [spring-boot-autoconfigure-1.5.6.RELEASE.jar:1.5.6.RELEASE]
    at org.springframework.cglib.proxy.MethodProxy.invokeSuper(MethodProxy.java:228) [spring-core-4.3.10.RELEASE.jar:4.3.10.RELEASE]
    at org.springframework.context.annotation.ConfigurationClassEnhancer$BeanMethodInterceptor.intercept(ConfigurationClassEnhancer.java:358) [spring-context-4.3.10.RELEASE.jar:4.3.10.RELEASE]



org.springframework.beans.factory.BeanCreationException: Error creating bean with name 'entityManagerFactory' defined in class path resource [org/springframework/boot/autoconfigure/orm/jpa/HibernateJpaAutoConfiguration.class]: Invocation of init method failed; nested exception is org.hibernate.service.spi.ServiceException: Unable to create requested service [org.hibernate.engine.jdbc.env.spi.JdbcEnvironment]
    at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.initializeBean(AbstractAutowireCapableBeanFactory.java:1628) ~[spring-beans-4.3.10.RELEASE.jar:4.3.10.RELEASE]
    at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.doCreateBean(AbstractAutowireCapableBeanFactory.java:555) ~[spring-beans-4.3.10.RELEASE.jar:4.3.10.RELEASE]
    at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.createBean(AbstractAutowireCapableBeanFactory.java:483) ~[spring-beans-4.3.10.RELEASE.jar:4.3.10.RELEASE]
    at org.springframework.beans.factory.support.AbstractBeanFactory$1.getObject(AbstractBeanFactory.java:306) ~[spring-beans-4.3.10.RELEASE.jar:4.3.10.RELEASE]
    at org.springframework.beans.factory.support.DefaultSingletonBeanRegistry.getSingleton(DefaultSingletonBeanRegistry.java:230) ~[spring-beans-4.3.10.RELEASE.jar:4.3.10.RELEASE]
    at org.springframework.beans.factory.support.AbstractBeanFactory.doGetBean(AbstractBeanFactory.java:302) ~[spring-beans-4.3.10.RELEASE.jar:4.3.10.RELEASE]
    at org.springframework.beans.factory.support.AbstractBeanFactory.getBean(AbstractBeanFactory.java:197) ~[spring-beans-4.3.10.RELEASE.jar:4.3.10.RELEASE]
    at org.springframework.context.support.AbstractApplicationContext.getBean(AbstractApplicationContext.java:1078) ~[spring-context-4.3.10.RELEASE.jar:4.3.10.RELEASE]
    at org.springframework.context.support.AbstractApplicationContext.finishBeanFactoryInitialization(AbstractApplicationContext.java:857) ~[spring-context-4.3.10.RELEASE.jar:4.3.10.RELEASE]
    at org.springframework.context.support.AbstractApplicationContext.refresh(AbstractApplicationContext.java:543) ~[spring-context-4.3.10.RELEASE.jar:4.3.10.RELEASE]
    at org.springframework.boot.context.embedded.EmbeddedWebApplicationContext.refresh(EmbeddedWebApplicationContext.java:122) ~[spring-boot-1.5.6.RELEASE.jar:1.5.6.RELEASE]
    at org.springframework.boot.SpringApplication.refresh(SpringApplication.java:693) [spring-boot-1.5.6.RELEASE.jar:1.5.6.RELEASE]
    at org.springframework.boot.SpringApplication.refreshContext(SpringApplication.java:360) [spring-boot-1.5.6.RELEASE.jar:1.5.6.RELEASE]
    at org.springframework.boot.SpringApplication.run(SpringApplication.java:303) [spring-boot-1.5.6.RELEASE.jar:1.5.6.RELEASE]
    at org.springframework.boot.SpringApplication.run(SpringApplication.java:1118) [spring-boot-1.5.6.RELEASE.jar:1.5.6.RELEASE]
    at org.springframework.boot.SpringApplication.run(SpringApplication.java:1107) [spring-boot-1.5.6.RELEASE.jar:1.5.6.RELEASE]
    at com.rfboernehave.demo.DemoApplication.main(DemoApplication.java:10) [classes/:na]

Caused by: org.hibernate.service.spi.ServiceException: Unable to create requested service [org.hibernate.engine.jdbc.env.spi.JdbcEnvironment]
at org.springframework.orm.jpa.vendor.SpringHibernateJpaPersistenceProvider.createContainerEntityManagerFactory(SpringHibernateJpaPersistenceProvider.java:60) ~[spring-orm-4.3.10.RELEASE.jar:4.3.10.RELEASE]
    at org.springframework.orm.jpa.LocalContainerEntityManagerFactoryBean.createNativeEntityManagerFactory(LocalContainerEntityManagerFactoryBean.java:353) ~[spring-orm-4.3.10.RELEASE.jar:4.3.10.RELEASE]
    at org.springframework.orm.jpa.AbstractEntityManagerFactoryBean.buildNativeEntityManagerFactory(AbstractEntityManagerFactoryBean.java:370) ~[spring-orm-4.3.10.RELEASE.jar:4.3.10.RELEASE]
    at org.springframework.orm.jpa.AbstractEntityManagerFactoryBean.afterPropertiesSet(AbstractEntityManagerFactoryBean.java:359) ~[spring-orm-4.3.10.RELEASE.jar:4.3.10.RELEASE]
    at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.invokeInitMethods(AbstractAutowireCapableBeanFactory.java:1687) ~[spring-beans-4.3.10.RELEASE.jar:4.3.10.RELEASE]
    at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.initializeBean(AbstractAutowireCapableBeanFactory.java:1624) ~[spring-beans-4.3.10.RELEASE.jar:4.3.10.RELEASE]


Caused by: org.hibernate.HibernateException: Access to DialectResolutionInfo cannot be null when 'hibernate.dialect' not set

现在我尝试添加 hibernate 依赖项:

<dependency>
            <groupId>org.hibernate</groupId>
            <artifactId>hibernate-core</artifactId>
            <version>4.1.4.Final</version>
        </dependency>
        <dependency>
            <groupId>org.hibernate</groupId>
            <artifactId>hibernate-entitymanager</artifactId>
            <version>5.2.3.Final</version>
        </dependency>

这给了我另一个错误:

:: Spring Boot ::        (v1.5.6.RELEASE)

2018-05-04 16:36:20.358  INFO 19272 --- [           main] com.rfboernehave.demo.DemoApplication    : Starting DemoApplication on DESKTOP-QB8IIQF with PID 19272 (C:\Users\nerdi\SpringbootWebAppMiniproject1\target\classes started by nerdi in C:\Users\nerdi\SpringbootWebAppMiniproject1)
2018-05-04 16:36:20.358  INFO 19272 --- [           main] com.rfboernehave.demo.DemoApplication    : No active profile set, falling back to default profiles: default
2018-05-04 16:36:21.064  INFO 19272 --- [           main] ationConfigEmbeddedWebApplicationContext : Refreshing org.springframework.boot.context.embedded.AnnotationConfigEmbeddedWebApplicationContext@77be656f: startup date [Fri May 04 16:36:21 CEST 2018]; root of context hierarchy
2018-05-04 16:36:23.488  INFO 19272 --- [           main] s.b.c.e.t.TomcatEmbeddedServletContainer : Tomcat initialized with port(s): 5000 (http)
2018-05-04 16:36:23.501  INFO 19272 --- [           main] o.apache.catalina.core.StandardService   : Starting service [Tomcat]
2018-05-04 16:36:23.501  INFO 19272 --- [           main] org.apache.catalina.core.StandardEngine  : Starting Servlet Engine: Apache Tomcat/8.5.16
2018-05-04 16:36:23.722  INFO 19272 --- [ost-startStop-1] o.a.c.c.C.[Tomcat].[localhost].[/]       : Initializing Spring embedded WebApplicationContext
2018-05-04 16:36:23.722  INFO 19272 --- [ost-startStop-1] o.s.web.context.ContextLoader            : Root WebApplicationContext: initialization completed in 2658 ms
2018-05-04 16:36:23.935  INFO 19272 --- [ost-startStop-1] o.s.b.w.servlet.FilterRegistrationBean   : Mapping filter: 'characterEncodingFilter' to: [/*]
2018-05-04 16:36:23.935  INFO 19272 --- [ost-startStop-1] o.s.b.w.servlet.FilterRegistrationBean   : Mapping filter: 'hiddenHttpMethodFilter' to: [/*]
2018-05-04 16:36:23.935  INFO 19272 --- [ost-startStop-1] o.s.b.w.servlet.FilterRegistrationBean   : Mapping filter: 'httpPutFormContentFilter' to: [/*]
2018-05-04 16:36:23.935  INFO 19272 --- [ost-startStop-1] o.s.b.w.servlet.FilterRegistrationBean   : Mapping filter: 'requestContextFilter' to: [/*]
2018-05-04 16:36:23.938  INFO 19272 --- [ost-startStop-1] .s.DelegatingFilterProxyRegistrationBean : Mapping filter: 'springSecurityFilterChain' to: [/*]
2018-05-04 16:36:23.939  INFO 19272 --- [ost-startStop-1] o.s.b.w.servlet.ServletRegistrationBean  : Mapping servlet: 'dispatcherServlet' to [/]
2018-05-04 16:36:24.010  WARN 19272 --- [           main] ationConfigEmbeddedWebApplicationContext : Exception encountered during context initialization - cancelling refresh attempt: org.springframework.beans.factory.UnsatisfiedDependencyException: Error creating bean with name 'homeController' defined in file [C:\Users\nerdi\SpringbootWebAppMiniproject1\target\classes\com\rfboernehave\demo\controller\HomeController.class]: Unsatisfied dependency expressed through constructor parameter 0; nested exception is org.springframework.beans.factory.UnsatisfiedDependencyException: Error creating bean with name 'brugerServiceImpl' defined in file [C:\Users\nerdi\SpringbootWebAppMiniproject1\target\classes\com\rfboernehave\demo\services\BrugerServiceImpl.class]: Unsatisfied dependency expressed through constructor parameter 0; nested exception is org.springframework.beans.factory.BeanCreationException: Error creating bean with name 'brugerRepository': Cannot create inner bean '(inner bean)#703feacd' of type [org.springframework.orm.jpa.SharedEntityManagerCreator] while setting bean property 'entityManager'; nested exception is org.springframework.beans.factory.BeanCreationException: Error creating bean with name '(inner bean)#703feacd': Cannot resolve reference to bean 'entityManagerFactory' while setting constructor argument; nested exception is org.springframework.beans.factory.NoSuchBeanDefinitionException: No bean named 'entityManagerFactory' available
2018-05-04 16:36:24.012  INFO 19272 --- [           main] o.apache.catalina.core.StandardService   : Stopping service [Tomcat]
2018-05-04 16:36:24.036  INFO 19272 --- [           main] utoConfigurationReportLoggingInitializer : 

Error starting ApplicationContext. To display the auto-configuration report re-run your application with 'debug' enabled.
2018-05-04 16:36:24.114 ERROR 19272 --- [           main] o.s.b.d.LoggingFailureAnalysisReporter   : 

***************************
APPLICATION FAILED TO START
***************************

Description:

Parameter 0 of constructor in com.rfboernehave.demo.services.BrugerServiceImpl required a bean named 'entityManagerFactory' that could not be found.


Action:

Consider defining a bean named 'entityManagerFactory' in your configuration.

现在我也摆脱了这个东西(虽然不确定是否正确)但是它给了我一个类似的错误但是要求我定义一个包类型的bean。我决定删除依赖项，因此目前正在处理帖子的第一个错误。

下面是我当前的 pom.xml:

<?xml version="1.0" encoding="UTF-8"?>
<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>com.rfboernhave</groupId>
    <artifactId>demo</artifactId>
    <version>0.0.1-SNAPSHOT</version>
    <packaging>jar</packaging>

    <name>demo</name>
    <description>Demo project for Spring Boot</description>

    <parent>
        <groupId>org.springframework.boot</groupId>
        <artifactId>spring-boot-starter-parent</artifactId>
        <version>1.5.6.RELEASE</version>
        <relativePath/> <!-- lookup parent from repository -->
    </parent>

    <properties>
        <project.build.sourceEncoding>UTF-8</project.build.sourceEncoding>
        <project.reporting.outputEncoding>UTF-8</project.reporting.outputEncoding>
        <java.version>1.8</java.version>
        <org.springframework.security.version>3.2.3.RELEASE</org.springframework.security.version>
        <org.springframework.version>4.0.4.RELEASE</org.springframework.version>
    </properties>


    <dependencies>
        <dependency>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-starter-data-jpa</artifactId>
        </dependency>
        <dependency>
            <groupId>com.h2database</groupId>
            <artifactId>h2</artifactId>
            <scope>runtime</scope>
        </dependency>
        <dependency>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-starter-thymeleaf</artifactId>
        </dependency>
        <dependency>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-starter-web</artifactId>
        </dependency>
        <dependency>
            <groupId>org.webjars</groupId>
            <artifactId>bootstrap</artifactId>
            <version>3.3.7</version>
        </dependency>
        <dependency>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-starter-test</artifactId>
            <scope>test</scope>
        </dependency>

        <dependency>
            <groupId>com.fasterxml</groupId>
            <artifactId>oss-parent</artifactId>
            <version>27</version>
        </dependency>





        <dependency>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-starter-test</artifactId>
            <scope>test</scope>
        </dependency>
        <dependency>
            <groupId>mysql</groupId>
            <artifactId>mysql-connector-java</artifactId>
        </dependency>
        <dependency>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-starter-security</artifactId>
            <version>2.0.1.RELEASE</version>
        </dependency>



    </dependencies>

    <build>
        <plugins>
            <plugin>
                <groupId>org.springframework.boot</groupId>
                <artifactId>spring-boot-maven-plugin</artifactId>
            </plugin>
        </plugins>
    </build>



</project>

我的应用程序.properties:

server.port=5000
spring.datasource.url=jdbc:mysql://localhost:5000/test_db
spring.datasource.username=root
spring.datasource.password=
spring.datasource.driver-class-name=com.mysql.jdbc.Driver

我的 Config.java 类:

package com.rfboernehave.demo.Security;


import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.context.annotation.Configuration;
import org.springframework.security.config.annotation.authentication.builders.AuthenticationManagerBuilder;
import org.springframework.security.config.annotation.web.builders.HttpSecurity;
import org.springframework.security.config.annotation.web.configuration.EnableWebSecurity;
import org.springframework.security.config.annotation.web.configuration.WebSecurityConfigurerAdapter;

import javax.sql.DataSource;

@Configuration
@EnableWebSecurity
public class Config extends WebSecurityConfigurerAdapter {


    @Autowired
    DataSource dataSource;



    @Override
    protected void configure(AuthenticationManagerBuilder auth) throws Exception{

        auth.jdbcAuthentication().dataSource(dataSource)
                .usersByUsernameQuery("select username, password from user where username=?")
                .authoritiesByUsernameQuery("select username, rolle from user where username=?");

    }

    @Override
    protected void configure(HttpSecurity http) throws Exception{
        http
            .authorizeRequests()
            .antMatchers("/login*").anonymous()
            .anyRequest().authenticated()
            .and()
            .formLogin()
            .loginPage("/login")
            .defaultSuccessUrl("/home")

            .and()
            .logout().logoutSuccessUrl("/login");
    }

}

我的实体(MyUser)类:对于外语快速翻译中的变量，我深表歉意:MinBruger 是(我的用户)brugernavn 是(用户名)adgangskode 是(密码)role是(角色)

package com.rfboernehave.demo.domains;

import javax.persistence.Entity;
import javax.persistence.GeneratedValue;
import javax.persistence.GenerationType;
import javax.persistence.Id;

@Entity
public class MinBruger {

    @Id
    @GeneratedValue(strategy = GenerationType.AUTO)
    private String brugernavn;
    private String adgangskode;
    private String rolle;
    private int id;

    public MinBruger() {
    }

    public MinBruger(int id, String brugernavn, String adgangskode, String rolle) {
        this.id = id;
        this.brugernavn = brugernavn;
        this.adgangskode = adgangskode;
        this.rolle = rolle;
    }

    public int getId() {
        return id;
    }

    public void setId(int id) {
        this.id = id;
    }

    public String getBrugernavn() {
        return brugernavn;
    }

    public void setBrugernavn(String brugernavn) {
        this.brugernavn = brugernavn;
    }

    public String getAdgangskode() {
        return adgangskode;
    }

    public void setAdgangskode(String adgangskode) {
        this.adgangskode = adgangskode;
    }

    public String getRolle(){return rolle;}

    public void setRolle(String rolle) {
        this.rolle = rolle;
    }

    @Override
    public String toString() {
        return "MinBruger{" +
                "id=" + id +
                ", brugernavn='" + brugernavn + '\'' +
                ", adgangskode='" + adgangskode + '\'' +
                ", rolle=" + rolle + '\'' +
                '}';
    }

下面是我的 UserRepository:翻译:BrugerRepository 是 (UserRepository)

package com.rfboernehave.demo.repositories;

import com.rfboernehave.demo.domains.MinBruger;
import org.springframework.data.repository.CrudRepository;
import org.springframework.stereotype.Repository;

@Repository
public interface BrugerRepository extends CrudRepository<MinBruger, String> {

}

我该如何解决这个问题？提前致谢。

最佳答案

更新:好的，所以我坐了下来:

spring.jpa.properties.hibernate.dialect = org.hibernate.dialect.MySQL5Dialect

除此之外，我还更改了以下内容:

spring.datasource.url=jdbc:mysql://localhost:3306/

收件人:

spring.datasource.url=jdbc:mysql://localhost:3306/test_db?useSSL=false

这似乎起到了部分作用，我的项目现在运行了，但是出现了一个新问题，当尝试登录时失败并设置 url 来自:http://localhost:5000/login

收件人:http://localhost:5000/login?error

下面是我的 HomeController.java:

        package com.rfboernehave.demo.controller;

import com.rfboernehave.demo.domains.Barn;
import com.rfboernehave.demo.domains.MinBruger;
import com.rfboernehave.demo.services.BarnServiceImpl;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.security.core.authority.SimpleGrantedAuthority;
import org.springframework.security.core.context.SecurityContextHolder;
import org.springframework.stereotype.Controller;
import org.springframework.ui.Model;
import org.springframework.web.bind.annotation.*;

import java.io.FileNotFoundException;
import java.util.ArrayList;

@Controller
public class HomeController {


    private final Logger log = LoggerFactory.getLogger(this.getClass());


    @Autowired

    private BarnServiceImpl barnService;


    public HomeController() {
    }


    @RequestMapping(value = {"", "/", "index"}, method = RequestMethod.GET)
    public String index() {
        log.info("index method called...");


        return "login";
    }

    @RequestMapping(value = "/login", method = RequestMethod.GET)
    public String login() {
        log.info("login method called with: ");

        if (SecurityContextHolder.getContext().getAuthentication().getAuthorities().contains(new SimpleGrantedAuthority("admin"))) {
            return "redirect:/home";
        }

        return "login";
    }
//
//
   @RequestMapping(value = "/home", method = RequestMethod.GET)
    public String home(Model model) {
       log.info("home action called...");

       model.addAttribute("boern", barnService.hentAlleBoern());

       log.info("home action ended...");
       return "home";
   }


    @GetMapping("/registrer")
    public String registrer(Model model) {
        log.info("registrer action called...");
        model.addAttribute("barn", new Barn());
        return "registrer";
    }

    @PostMapping("/registrer")
    public String registrer(@ModelAttribute Barn barn, Model model) throws FileNotFoundException {
        log.info("registrer post action called...");
        String home = Integer.toString(barnService.hentAlleBoern().size());
        barn.setId(Integer.parseInt(home));
        barnService.hentAlleBoern().add(barn);
        barnService.printToFile();
        model.addAttribute("boern", barnService.hentAlleBoern());
        return "/home";
    }

    @GetMapping("/detaljer/{id}")
    public String detaljer(@PathVariable("id") int id, Model model) {
        log.info("detaljer action called...");


        Barn lille = null;


        for (Barn barn : barnService.hentAlleBoern()) {
            if (barn.getId() == id) {
                lille = barn;
                break;
            }
        }

        model.addAttribute("barn", lille);
        model.addAttribute("boern", barnService.hentAlleBoern());



        return "detaljer";
    }

    @GetMapping("/afmeld/{id}")
    public String afmeld(@PathVariable("id") int id, Model model) {
        log.info("afmeld  action called...");
        model.addAttribute("barn",barnService.hentAlleBoern().get(id));
        model.addAttribute("boern", barnService.hentAlleBoern());
        return "afmeld";
    }

    @PostMapping("/afmeld")
    public String afmeld(@ModelAttribute Barn barn, Model model) throws FileNotFoundException {
        log.info("afmeld post action called...");
        int id = barn.getId();
        barnService.hentAlleBoern().remove(barn.getId());

        leftShiftId(barnService.hentAlleBoern(), id);
        barnService.printToFile();
        model.addAttribute("boern", barnService.hentAlleBoern());
        return "/home";
    }

    @GetMapping("/rediger/{id}")
    public String rediger(@PathVariable("id") int id, Model model) {
        log.info("rediger action called...");


        model.addAttribute("barn", barnService.hentAlleBoern().get(id));
        model.addAttribute("boern", barnService.hentAlleBoern());
        return "rediger";
    }

    @PostMapping("/rediger")
    public String rediger(@ModelAttribute Barn barn, Model model) throws FileNotFoundException {
        log.info("rediger post action called...");
        for (int i = 0; i < barnService.hentAlleBoern().size(); i++) {
            if (barn.getId() == barnService.hentAlleBoern().get(i).getId()) {
                barnService.hentAlleBoern().set(i, barn);

                break;
            }
        }
        barnService.printToFile();
        model.addAttribute("boern", barnService.hentAlleBoern());
        return "/home";
    }

    private void leftShiftId(ArrayList<Barn> list, int id) {
        log.info("leftshift method called...");
        for (int i = id; i < list.size(); i++) {
            Barn barn = list.get(i);
            barn.setId(barn.getId() - 1);
        }
    }

}

终端输出如下:

 .   ____          _            __ _ _
 /\\ / ___'_ __ _ _(_)_ __  __ _ \ \ \ \
( ( )\___ | '_ | '_| | '_ \/ _` | \ \ \ \
 \\/  ___)| |_)| | | | | || (_| |  ) ) ) )
  '  |____| .__|_| |_|_| |_\__, | / / / /
 =========|_|==============|___/=/_/_/_/
 :: Spring Boot ::        (v1.5.6.RELEASE)

2018-05-08 13:18:32.979  INFO 1872 --- [           main] com.rfboernehave.demo.DemoApplication    : Starting DemoApplication on DESKTOP-QB8IIQF with PID 1872 (C:\Users\nerdi\SpringbootWebAppMiniproject1\target\classes started by nerdi in C:\Users\nerdi\SpringbootWebAppMiniproject1)
2018-05-08 13:18:32.982  INFO 1872 --- [           main] com.rfboernehave.demo.DemoApplication    : No active profile set, falling back to default profiles: default
2018-05-08 13:18:33.671  INFO 1872 --- [           main] ationConfigEmbeddedWebApplicationContext : Refreshing org.springframework.boot.context.embedded.AnnotationConfigEmbeddedWebApplicationContext@516be40f: startup date [Tue May 08 13:18:33 CEST 2018]; root of context hierarchy
2018-05-08 13:18:36.652  INFO 1872 --- [           main] s.b.c.e.t.TomcatEmbeddedServletContainer : Tomcat initialized with port(s): 5000 (http)
2018-05-08 13:18:36.666  INFO 1872 --- [           main] o.apache.catalina.core.StandardService   : Starting service [Tomcat]
2018-05-08 13:18:36.667  INFO 1872 --- [           main] org.apache.catalina.core.StandardEngine  : Starting Servlet Engine: Apache Tomcat/8.5.16
2018-05-08 13:18:36.878  INFO 1872 --- [ost-startStop-1] o.a.c.c.C.[Tomcat].[localhost].[/]       : Initializing Spring embedded WebApplicationContext
2018-05-08 13:18:36.878  INFO 1872 --- [ost-startStop-1] o.s.web.context.ContextLoader            : Root WebApplicationContext: initialization completed in 3210 ms
2018-05-08 13:18:37.170  INFO 1872 --- [ost-startStop-1] o.s.b.w.servlet.FilterRegistrationBean   : Mapping filter: 'characterEncodingFilter' to: [/*]
2018-05-08 13:18:37.170  INFO 1872 --- [ost-startStop-1] o.s.b.w.servlet.FilterRegistrationBean   : Mapping filter: 'hiddenHttpMethodFilter' to: [/*]
2018-05-08 13:18:37.170  INFO 1872 --- [ost-startStop-1] o.s.b.w.servlet.FilterRegistrationBean   : Mapping filter: 'httpPutFormContentFilter' to: [/*]
2018-05-08 13:18:37.170  INFO 1872 --- [ost-startStop-1] o.s.b.w.servlet.FilterRegistrationBean   : Mapping filter: 'requestContextFilter' to: [/*]
2018-05-08 13:18:37.172  INFO 1872 --- [ost-startStop-1] .s.DelegatingFilterProxyRegistrationBean : Mapping filter: 'springSecurityFilterChain' to: [/*]
2018-05-08 13:18:37.172  INFO 1872 --- [ost-startStop-1] o.s.b.w.servlet.ServletRegistrationBean  : Mapping servlet: 'dispatcherServlet' to [/]
2018-05-08 13:18:37.907  INFO 1872 --- [           main] j.LocalContainerEntityManagerFactoryBean : Building JPA container EntityManagerFactory for persistence unit 'default'
2018-05-08 13:18:37.929  INFO 1872 --- [           main] o.hibernate.jpa.internal.util.LogHelper  : HHH000204: Processing PersistenceUnitInfo [
    name: default
    ...]
2018-05-08 13:18:38.204  INFO 1872 --- [           main] org.hibernate.Version                    : HHH000412: Hibernate Core {5.0.12.Final}
2018-05-08 13:18:38.205  INFO 1872 --- [           main] org.hibernate.cfg.Environment            : HHH000206: hibernate.properties not found
2018-05-08 13:18:38.207  INFO 1872 --- [           main] org.hibernate.cfg.Environment            : HHH000021: Bytecode provider name : javassist
2018-05-08 13:18:38.256  INFO 1872 --- [           main] o.hibernate.annotations.common.Version   : HCANN000001: Hibernate Commons Annotations {5.0.1.Final}
2018-05-08 13:18:38.425  INFO 1872 --- [           main] org.hibernate.dialect.Dialect            : HHH000400: Using dialect: org.hibernate.dialect.MySQL5Dialect
2018-05-08 13:18:39.001  INFO 1872 --- [           main] j.LocalContainerEntityManagerFactoryBean : Initialized JPA EntityManagerFactory for persistence unit 'default'
2018-05-08 13:18:39.571  INFO 1872 --- [           main] o.s.s.web.DefaultSecurityFilterChain     : Creating filter chain: org.springframework.security.web.util.matcher.AnyRequestMatcher@1, [org.springframework.security.web.context.request.async.WebAsyncManagerIntegrationFilter@11b5f4e2, org.springframework.security.web.context.SecurityContextPersistenceFilter@33e0c716, org.springframework.security.web.header.HeaderWriterFilter@634ca3e7, org.springframework.security.web.csrf.CsrfFilter@6ee88e21, org.springframework.security.web.authentication.logout.LogoutFilter@d653e41, org.springframework.security.web.authentication.UsernamePasswordAuthenticationFilter@17222c11, org.springframework.security.web.savedrequest.RequestCacheAwareFilter@6274f21c, org.springframework.security.web.servletapi.SecurityContextHolderAwareRequestFilter@12952aff, org.springframework.security.web.authentication.AnonymousAuthenticationFilter@6bcae9, org.springframework.security.web.session.SessionManagementFilter@b14b60a, org.springframework.security.web.access.ExceptionTranslationFilter@50b734c4, org.springframework.security.web.access.intercept.FilterSecurityInterceptor@67688110]
2018-05-08 13:18:40.196  INFO 1872 --- [           main] s.w.s.m.m.a.RequestMappingHandlerAdapter : Looking for @ControllerAdvice: org.springframework.boot.context.embedded.AnnotationConfigEmbeddedWebApplicationContext@516be40f: startup date [Tue May 08 13:18:33 CEST 2018]; root of context hierarchy
2018-05-08 13:18:40.337  INFO 1872 --- [           main] s.w.s.m.m.a.RequestMappingHandlerMapping : Mapped "{[ || / || /index],methods=[GET]}" onto public java.lang.String com.rfboernehave.demo.controller.HomeController.index()
2018-05-08 13:18:40.338  INFO 1872 --- [           main] s.w.s.m.m.a.RequestMappingHandlerMapping : Mapped "{[/home],methods=[GET]}" onto public java.lang.String com.rfboernehave.demo.controller.HomeController.home(org.springframework.ui.Model)
2018-05-08 13:18:40.339  INFO 1872 --- [           main] s.w.s.m.m.a.RequestMappingHandlerMapping : Mapped "{[/rediger],methods=[POST]}" onto public java.lang.String com.rfboernehave.demo.controller.HomeController.rediger(com.rfboernehave.demo.domains.Barn,org.springframework.ui.Model) throws java.io.FileNotFoundException
2018-05-08 13:18:40.339  INFO 1872 --- [           main] s.w.s.m.m.a.RequestMappingHandlerMapping : Mapped "{[/rediger/{id}],methods=[GET]}" onto public java.lang.String com.rfboernehave.demo.controller.HomeController.rediger(int,org.springframework.ui.Model)
2018-05-08 13:18:40.340  INFO 1872 --- [           main] s.w.s.m.m.a.RequestMappingHandlerMapping : Mapped "{[/detaljer/{id}],methods=[GET]}" onto public java.lang.String com.rfboernehave.demo.controller.HomeController.detaljer(int,org.springframework.ui.Model)
2018-05-08 13:18:40.341  INFO 1872 --- [           main] s.w.s.m.m.a.RequestMappingHandlerMapping : Mapped "{[/login],methods=[GET]}" onto public java.lang.String com.rfboernehave.demo.controller.HomeController.login()
2018-05-08 13:18:40.342  INFO 1872 --- [           main] s.w.s.m.m.a.RequestMappingHandlerMapping : Mapped "{[/registrer],methods=[POST]}" onto public java.lang.String com.rfboernehave.demo.controller.HomeController.registrer(com.rfboernehave.demo.domains.Barn,org.springframework.ui.Model) throws java.io.FileNotFoundException
2018-05-08 13:18:40.342  INFO 1872 --- [           main] s.w.s.m.m.a.RequestMappingHandlerMapping : Mapped "{[/registrer],methods=[GET]}" onto public java.lang.String com.rfboernehave.demo.controller.HomeController.registrer(org.springframework.ui.Model)
2018-05-08 13:18:40.343  INFO 1872 --- [           main] s.w.s.m.m.a.RequestMappingHandlerMapping : Mapped "{[/afmeld],methods=[POST]}" onto public java.lang.String com.rfboernehave.demo.controller.HomeController.afmeld(com.rfboernehave.demo.domains.Barn,org.springframework.ui.Model) throws java.io.FileNotFoundException
2018-05-08 13:18:40.344  INFO 1872 --- [           main] s.w.s.m.m.a.RequestMappingHandlerMapping : Mapped "{[/afmeld/{id}],methods=[GET]}" onto public java.lang.String com.rfboernehave.demo.controller.HomeController.afmeld(int,org.springframework.ui.Model)
2018-05-08 13:18:40.347  INFO 1872 --- [           main] s.w.s.m.m.a.RequestMappingHandlerMapping : Mapped "{[/error]}" onto public org.springframework.http.ResponseEntity<java.util.Map<java.lang.String, java.lang.Object>> org.springframework.boot.autoconfigure.web.BasicErrorController.error(javax.servlet.http.HttpServletRequest)
2018-05-08 13:18:40.348  INFO 1872 --- [           main] s.w.s.m.m.a.RequestMappingHandlerMapping : Mapped "{[/error],produces=[text/html]}" onto public org.springframework.web.servlet.ModelAndView org.springframework.boot.autoconfigure.web.BasicErrorController.errorHtml(javax.servlet.http.HttpServletRequest,javax.servlet.http.HttpServletResponse)
2018-05-08 13:18:40.398  INFO 1872 --- [           main] o.s.w.s.handler.SimpleUrlHandlerMapping  : Mapped URL path [/webjars/**] onto handler of type [class org.springframework.web.servlet.resource.ResourceHttpRequestHandler]
2018-05-08 13:18:40.400  INFO 1872 --- [           main] o.s.w.s.handler.SimpleUrlHandlerMapping  : Mapped URL path [/**] onto handler of type [class org.springframework.web.servlet.resource.ResourceHttpRequestHandler]
2018-05-08 13:18:40.477  INFO 1872 --- [           main] o.s.w.s.handler.SimpleUrlHandlerMapping  : Mapped URL path [/**/favicon.ico] onto handler of type [class org.springframework.web.servlet.resource.ResourceHttpRequestHandler]
2018-05-08 13:18:41.111  INFO 1872 --- [           main] b.a.s.AuthenticationManagerConfiguration : 

Using default security password: 4f2b3afb-8328-4fa1-a16c-e16003f15618

2018-05-08 13:18:41.294  INFO 1872 --- [           main] o.s.j.e.a.AnnotationMBeanExporter        : Registering beans for JMX exposure on startup
2018-05-08 13:18:41.396  INFO 1872 --- [           main] s.b.c.e.t.TomcatEmbeddedServletContainer : Tomcat started on port(s): 5000 (http)
2018-05-08 13:18:41.403  INFO 1872 --- [           main] com.rfboernehave.demo.DemoApplication    : Started DemoApplication in 8.91 seconds (JVM running for 9.612)

关于java - com.mysql.jdbc.exceptions.jdbc4.CommunicationsException : Communications link failure AND BeanEntityManager error，我们在Stack Overflow上找到一个类似的问题： https://stackoverflow.com/questions/50183566/

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java - com.mysql.jdbc.exceptions.jdbc4.CommunicationsException : Communications link failure AND BeanEntityManager error