Question

这个问题已被多次询问，但没有一个给定的答案解决了我的问题：我使用IntelliJ IDEA 15.0.1创建了一个新的Grails 3项目，不添加额外的代码：它运行。当我尝试配置我的项目以连接到MySql数据库时，我遇到以下错误：

ERROR org.apache.tomcat.jdbc.pool.ConnectionPool - Unable to create initial connections of pool. java.sql.SQLException: Unable to load class: com.mysql.jdbc.Driver from ClassLoader:sun.misc.Launcher$AppClassLoader@77abfbdc;ClassLoader:sun.misc.Launcher$AppClassLoader@77abfbdc
at org.apache.tomcat.jdbc.pool.PooledConnection.connectUsingDriver(PooledConnection.java:280)
at org.apache.tomcat.jdbc.pool.PooledConnection.connect(PooledConnection.java:200)
at org.apache.tomcat.jdbc.pool.ConnectionPool.createConnection(ConnectionPool.java:708)
at org.apache.tomcat.jdbc.pool.ConnectionPool.borrowConnection(ConnectionPool.java:642)
at org.apache.tomcat.jdbc.pool.ConnectionPool.init(ConnectionPool.java:464)
at org.apache.tomcat.jdbc.pool.ConnectionPool.<init>(ConnectionPool.java:141)
at org.apache.tomcat.jdbc.pool.DataSourceProxy.pCreatePool(DataSourceProxy.java:115)
at org.apache.tomcat.jdbc.pool.DataSourceProxy.createPool(DataSourceProxy.java:102)
at org.apache.tomcat.jdbc.pool.DataSourceProxy.getConnection(DataSourceProxy.java:126)
at org.springframework.jdbc.datasource.LazyConnectionDataSourceProxy.afterPropertiesSet(LazyConnectionDataSourceProxy.java:162)
at org.springframework.jdbc.datasource.LazyConnectionDataSourceProxy.<init>(LazyConnectionDataSourceProxy.java:106)
at sun.reflect.NativeConstructorAccessorImpl.newInstance0(Native Method)
at sun.reflect.NativeConstructorAccessorImpl.newInstance(NativeConstructorAccessorImpl.java:57)
at sun.reflect.DelegatingConstructorAccessorImpl.newInstance(DelegatingConstructorAccessorImpl.java:45)
at java.lang.reflect.Constructor.newInstance(Constructor.java:526)
at org.springsource.loaded.ri.ReflectiveInterceptor.jlrConstructorNewInstance(ReflectiveInterceptor.java:1075)
at org.springframework.beans.BeanUtils.instantiateClass(BeanUtils.java:147)

我的配置是：JDK 1.7.072 / Grails 3.1.8 / IntelliJ 15.0.1

Build.gradle：

   buildscript {
    ext {
        grailsVersion = project.grailsVersion
    }
    repositories {
        mavenLocal()
        maven { url "https://repo.grails.org/grails/core" }
    }
    dependencies {
        classpath "org.grails:grails-gradle-plugin:$grailsVersion"
        classpath "com.bertramlabs.plugins:asset-pipeline-gradle:2.8.2"
        classpath "org.grails.plugins:hibernate4:5.0.6"
    }
}

version "0.1"
group "testgrails3"

apply plugin: "eclipse"
apply plugin: "idea"
apply plugin: "war"
apply plugin: "org.grails.grails-web"
apply plugin: "org.grails.grails-gsp"
apply plugin: "asset-pipeline"

ext {
    grailsVersion = project.grailsVersion
    gradleWrapperVersion = project.gradleWrapperVersion
}

repositories {
    mavenLocal()
    maven { url "https://repo.grails.org/grails/core" }
}

dependencyManagement {
    imports {
        mavenBom "org.grails:grails-bom:$grailsVersion"
    }
    applyMavenExclusions false
}

dependencies {

    compile "org.springframework.boot:spring-boot-starter-logging"
    compile "org.springframework.boot:spring-boot-autoconfigure"
    compile "org.grails:grails-core"
    compile "org.springframework.boot:spring-boot-starter-actuator"
    compile "org.springframework.boot:spring-boot-starter-tomcat"
    compile "org.grails:grails-dependencies"
    compile "org.grails:grails-web-boot"
    compile "org.grails.plugins:cache"
    compile "org.grails.plugins:scaffolding"
    compile "org.grails.plugins:hibernate4"
    compile "org.hibernate:hibernate-ehcache"
    console "org.grails:grails-console"
    profile "org.grails.profiles:web:3.1.8"
    runtime "com.bertramlabs.plugins:asset-pipeline-grails:2.8.2"
    runtime "mysql:mysql-connector-java:5.1.39"
    testCompile "org.grails:grails-plugin-testing"
    testCompile "org.grails.plugins:geb"
    testRuntime "org.seleniumhq.selenium:selenium-htmlunit-driver:2.47.1"
    testRuntime "net.sourceforge.htmlunit:htmlunit:2.18"
}

task wrapper(type: Wrapper) {
    gradleVersion = gradleWrapperVersion
}

assets {
    minifyJs = true
    minifyCss = true
}

Application.yml：

hibernate:
    cache:
        queries: false
        use_second_level_cache: true
        use_query_cache: false
        region.factory_class: 'org.hibernate.cache.ehcache.EhCacheRegionFactory'

dataSource:
    pooled: true
    jmxExport: true
    driverClassName: com.mysql.jdbc.Driver
    dialect: org.hibernate.dialect.MySQL5InnoDBDialect
    username: myuser
    password: mypassword

environments:
    development:
        dataSource:
            dbCreate: update
            url: jdbc:mysql://xxx.xxx.xxx.xxx:3306/myappdev;MVCC=TRUE;LOCK_TIMEOUT=10000;DB_CLOSE_ON_EXIT=FALSE
    test:
        dataSource:
            dbCreate: update
            url: jdbc:mysql://xxx.xxx.xxx.xxx:3306/myapptest;MVCC=TRUE;LOCK_TIMEOUT=10000;DB_CLOSE_ON_EXIT=FALSE
    production:
        dataSource:
            dbCreate: update
            url: jdbc:mysql://xxx.xxx.xxx.xxx:3306/myappprod;MVCC=TRUE;LOCK_TIMEOUT=10000;DB_CLOSE_ON_EXIT=FALSE
            properties:
                jmxEnabled: true
                initialSize: 5
                maxActive: 50
                minIdle: 5
                maxIdle: 25
                maxWait: 10000
                maxAge: 600000
                timeBetweenEvictionRunsMillis: 5000
                minEvictableIdleTimeMillis: 60000
                validationQuery: SELECT 1
                validationQueryTimeout: 3
                validationInterval: 15000
                testOnBorrow: true
                testWhileIdle: true
                testOnReturn: false
                jdbcInterceptors: ConnectionState
                defaultTransactionIsolation: 2 # TRANSACTION_READ_COMMITTED

---

当然，jdbc：mysql：//xxx.xxx.xxx.xxx：3306 /是一个有效的IP。

感谢您的帮助：我花了几天时间解决这个问题...

Answer 1

您的依赖项列表中没有mysql依赖项将其添加到依赖关系列表中：

x86_64

Answer 2

尝试使用 “在buildConfig中编译'mysql：mysql-connector-java：5.1.37'。显然你无法加载mysql conector类

IntelliJ 15 / Grails 3：无法连接到mySql DB

2 个答案: