我的mySQL服务器托管在ubuntu服务器vm @ 10.0.0.200上，ssh端口为3333。
尝试启动spring引导应用程序给我这个错误:
java.sql.SQLNonTransientConnectionException: Could not create connection to database server. Attempted reconnect 3 times. Giving up.
我的应用程序。属性如下:
spring.datasource.url = jdbc:mysql://10.0.0.200:3306/test?useSSL=false&allowPublicKeyRetrieval=true&autoReconnect=true
spring.datasource.username = boss
spring.datasource.password = StrongPass123!
spring.jpa.show-sql= true
spring.jpa.hibernate.ddl-auto= update
spring.jpa.properties.hibernate.dialect= org.hibernate.dialect.MySQL5Dialect
我想也许我需要为我的虚拟机指定ssh端口:
spring.datasource.url = jdbc:mysql://{10.0.0.200:3333}:3306/test?useSSL=false&allowPublicKeyRetrieval=true&autoReconnect=true
得到了相同的错误。我尝试将my.cnf中mysql的绑定地址设置为我的vm的IP(localhost)。没用。
我确信凭证是正确的，但还没有让春天开始正确。
错误跟踪:
java.sql.SQLNonTransientConnectionException: Could not create connection to database server. Attempted reconnect 3 times. Giving up.
at com.mysql.cj.jdbc.exceptions.SQLError.createSQLException(SQLError.java:110) ~[mysql-connector-java-8.0.29.jar:8.0.29]
at com.mysql.cj.jdbc.exceptions.SQLError.createSQLException(SQLError.java:97) ~[mysql-connector-java-8.0.29.jar:8.0.29]
at com.mysql.cj.jdbc.exceptions.SQLError.createSQLException(SQLError.java:89) ~[mysql-connector-java-8.0.29.jar:8.0.29]
at com.mysql.cj.jdbc.exceptions.SQLError.createSQLException(SQLError.java:63) ~[mysql-connector-java-8.0.29.jar:8.0.29]
at com.mysql.cj.jdbc.exceptions.SQLError.createSQLException(SQLError.java:73) ~[mysql-connector-java-8.0.29.jar:8.0.29]
at com.mysql.cj.jdbc.ConnectionImpl.connectWithRetries(ConnectionImpl.java:898) ~[mysql-connector-java-8.0.29.jar:8.0.29]
at com.mysql.cj.jdbc.ConnectionImpl.createNewIO(ConnectionImpl.java:823) ~[mysql-connector-java-8.0.29.jar:8.0.29]
at com.mysql.cj.jdbc.ConnectionImpl.<init>(ConnectionImpl.java:448) ~[mysql-connector-java-8.0.29.jar:8.0.29]
at com.mysql.cj.jdbc.ConnectionImpl.getInstance(ConnectionImpl.java:241) ~[mysql-connector-java-8.0.29.jar:8.0.29]
at com.mysql.cj.jdbc.NonRegisteringDriver.connect(NonRegisteringDriver.java:198) ~[mysql-connector-java-8.0.29.jar:8.0.29]
at com.zaxxer.hikari.util.DriverDataSource.getConnection(DriverDataSource.java:138) ~[HikariCP-4.0.3.jar:na]
at com.zaxxer.hikari.pool.PoolBase.newConnection(PoolBase.java:364) ~[HikariCP-4.0.3.jar:na]
at com.zaxxer.hikari.pool.PoolBase.newPoolEntry(PoolBase.java:206) ~[HikariCP-4.0.3.jar:na]
at com.zaxxer.hikari.pool.HikariPool.createPoolEntry(HikariPool.java:476) ~[HikariCP-4.0.3.jar:na]
at com.zaxxer.hikari.pool.HikariPool.checkFailFast(HikariPool.java:561) ~[HikariCP-4.0.3.jar:na]
at com.zaxxer.hikari.pool.HikariPool.<init>(HikariPool.java:115) ~[HikariCP-4.0.3.jar:na]
at com.zaxxer.hikari.HikariDataSource.getConnection(HikariDataSource.java:112) ~[HikariCP-4.0.3.jar:na]
at org.hibernate.engine.jdbc.connections.internal.DatasourceConnectionProviderImpl.getConnection(DatasourceConnectionProviderImpl.java:122) ~[hibernate-core-5.6.9.Final.jar:5.6.9.Final]
at org.hibernate.engine.jdbc.env.internal.JdbcEnvironmentInitiator$ConnectionProviderJdbcConnectionAccess.obtainConnection(JdbcEnvironmentInitiator.java:181) ~[hibernate-core-5.6.9.Final.jar:5.6.9.Final]
at org.hibernate.engine.jdbc.env.internal.JdbcEnvironmentInitiator.initiateService(JdbcEnvironmentInitiator.java:68) ~[hibernate-core-5.6.9.Final.jar:5.6.9.Final]
at org.hibernate.engine.jdbc.env.internal.JdbcEnvironmentInitiator.initiateService(JdbcEnvironmentInitiator.java:35) ~[hibernate-core-5.6.9.Final.jar:5.6.9.Final]
at org.hibernate.boot.registry.internal.StandardServiceRegistryImpl.initiateService(StandardServiceRegistryImpl.java:101) ~[hibernate-core-5.6.9.Final.jar:5.6.9.Final]
at org.hibernate.service.internal.AbstractServiceRegistryImpl.createService(AbstractServiceRegistryImpl.java:263) ~[hibernate-core-5.6.9.Final.jar:5.6.9.Final]
at org.hibernate.service.internal.AbstractServiceRegistryImpl.initializeService(AbstractServiceRegistryImpl.java:237) ~[hibernate-core-5.6.9.Final.jar:5.6.9.Final]
at org.hibernate.service.internal.AbstractServiceRegistryImpl.getService(AbstractServiceRegistryImpl.java:214)
~[hibernate-core-5.6.9.Final.jar:5.6.9.Final]
at org.hibernate.id.factory.internal.DefaultIdentifierGeneratorFactory.injectServices(DefaultIdentifierGeneratorFactory.java:175) ~[hibernate-core-5.6.9.Final.jar:5.6.9.Final]
at org.hibernate.service.internal.AbstractServiceRegistryImpl.injectDependencies(AbstractServiceRegistryImpl.java:286) ~[hibernate-core-5.6.9.Final.jar:5.6.9.Final]
at org.hibernate.service.internal.AbstractServiceRegistryImpl.initializeService(AbstractServiceRegistryImpl.java:243) ~[hibernate-core-5.6.9.Final.jar:5.6.9.Final]
at org.hibernate.service.internal.AbstractServiceRegistryImpl.getService(AbstractServiceRegistryImpl.java:214)
~[hibernate-core-5.6.9.Final.jar:5.6.9.Final]
at org.hibernate.boot.internal.InFlightMetadataCollectorImpl.<init>(InFlightMetadataCollectorImpl.java:173) ~[hibernate-core-5.6.9.Final.jar:5.6.9.Final]
at org.hibernate.boot.model.process.spi.MetadataBuildingProcess.complete(MetadataBuildingProcess.java:127) ~[hibernate-core-5.6.9.Final.jar:5.6.9.Final]
为了解决SQLNonTransientConnectionException错误，我首先建议使用这里的旧stackoverflow帖子中的策略:SQLNonTransientConnectionException:在我的应用程序中与Derby数据库交互时没有当前连接
如果这不起作用，那么我将尝试在应用程序中建模您的代码。属性代码:
spring.jpa.hibernate.ddl-auto=update
spring.datasource.url=jdbc:mysql://${MYSQL_HOST:localhost}:3306/db_example
spring.datasource.username=springuser
spring.datasource.password=ThePassword
spring.datasource.driver-class-name=com.mysql.cj.jdbc.Driver
#spring.jpa.show-sql: true
我在应用程序中找到了。属性https://spring.io/guides/gs/accessing-data-mysql/的属性部分。所以这些信息都是直接来自消息源的。如果您可以使它与spring标准示例中的结构一起工作，那么您可以一个接一个地添加其他属性，在测试连接之前构建并重新运行代码。
有时完全关闭IDE然后重新打开它也有帮助。