Docker化的SpringBoot应用，无法连接数据库

[永远的烟火]

The last packet sent successfully to the server was 0 milliseconds ago. The driver has not received any packets from the server.
	at sun.reflect.NativeConstructorAccessorImpl.newInstance0(Native Method) ~[na:1.8.0_111]
	at sun.reflect.NativeConstructorAccessorImpl.newInstance(NativeConstructorAccessorImpl.java:62) ~[na:1.8.0_111]
	at sun.reflect.DelegatingConstructorAccessorImpl.newInstance(DelegatingConstructorAccessorImpl.java:45) ~[na:1.8.0_111]
	at java.lang.reflect.Constructor.newInstance(Constructor.java:423) ~[na:1.8.0_111]
	at com.mysql.cj.exceptions.ExceptionFactory.createException(ExceptionFactory.java:61) ~[mysql-connector-java-8.0.15.jar!/:8.0.15]
	at com.mysql.cj.exceptions.ExceptionFactory.createException(ExceptionFactory.java:105) ~[mysql-connector-java-8.0.15.jar!/:8.0.15]
	at com.mysql.cj.exceptions.ExceptionFactory.createException(ExceptionFactory.java:151) ~[mysql-connector-java-8.0.15.jar!/:8.0.15]
	at com.mysql.cj.exceptions.ExceptionFactory.createCommunicationsException(ExceptionFactory.java:167) ~[mysql-connector-java-8.0.15.jar!/:8.0.15]
	at com.mysql.cj.protocol.a.NativeSocketConnection.connect(NativeSocketConnection.java:91) ~[mysql-connector-java-8.0.15.jar!/:8.0.15]
	at com.mysql.cj.NativeSession.connect(NativeSession.java:152) ~[mysql-connector-java-8.0.15.jar!/:8.0.15]
	at com.mysql.cj.jdbc.ConnectionImpl.connectOneTryOnly(ConnectionImpl.java:955) ~[mysql-connector-java-8.0.15.jar!/:8.0.15]
	at com.mysql.cj.jdbc.ConnectionImpl.createNewIO(ConnectionImpl.java:825) ~[mysql-connector-java-8.0.15.jar!/:8.0.15]
	... 56 common frames omitted
Caused by: java.net.ConnectException: Connection refused (Connection refused)
	at java.net.PlainSocketImpl.socketConnect(Native Method) ~[na:1.8.0_111]
	at java.net.AbstractPlainSocketImpl.doConnect(AbstractPlainSocketImpl.java:350) ~[na:1.8.0_111]
	at java.net.AbstractPlainSocketImpl.connectToAddress(AbstractPlainSocketImpl.java:206) ~[na:1.8.0_111]
	at java.net.AbstractPlainSocketImpl.connect(AbstractPlainSocketImpl.java:188) ~[na:1.8.0_111]
	at java.net.SocksSocketImpl.connect(SocksSocketImpl.java:392) ~[na:1.8.0_111]
	at java.net.Socket.connect(Socket.java:589) ~[na:1.8.0_111]
	at com.mysql.cj.protocol.StandardSocketFactory.connect(StandardSocketFactory.java:155) ~[mysql-connector-java-8.0.15.jar!/:8.0.15]
	at com.mysql.cj.protocol.a.NativeSocketConnection.connect(NativeSocketConnection.java:65) ~[mysql-connector-java-8.0.15.jar!/:8.0.15]
	... 59 common frames omitted

2019-03-24 12:30:22.961  WARN 1 --- [           main] o.h.engine.jdbc.spi.SqlExceptionHelper   : SQL Error

The last packet sent successfully to the server was 0 milliseconds ago. The driver has not received any packets from the server.
2019-03-24 12:30:22.980  WARN 1 --- [           main] ConfigServletWebServerApplicationContext : Exception encountered during context initialization - cancelling refresh attempt: org.springframework.beans.factory.BeanCreationException: Error creating bean with name 'entityManagerFactory' defined in class path resource [org/springframework/boot/autoconfigure/orm/jpa/HibernateJpaConfiguration.class]: Invocation of init method failed; nested exception is javax.persistence.PersistenceException: [PersistenceUnit: default] Unable to build Hibernate SessionFactory; nested exception is org.hibernate.exception.JDBCConnectionException: Unable to open JDBC Connection for DDL execution
2019-03-24 12:30:22.986  INFO 1 --- [           main] o.apache.catalina.core.StandardService   : Stopping service [Tomcat]
2019-03-24 12:30:23.026  INFO 1 --- [           main] ConditionEvaluationReportLoggingListener : 

Error starting ApplicationContext. To display the conditions report re-run your application with 'debug' enabled.
2019-03-24 12:30:23.036 ERROR 1 --- [           main] o.s.boot.SpringApplication               : Application run failed

org.springframework.beans.factory.BeanCreationException: Error creating bean with name 'entityManagerFactory' defined in class path resource [org/springframework/boot/autoconfigure/orm/jpa/HibernateJpaConfiguration.class]: Invocation of init method failed; nested exception is javax.persistence.PersistenceException: [PersistenceUnit: default] Unable to build Hibernate SessionFactory; nested exception is org.hibernate.exception.JDBCConnectionException: Unable to open JDBC Connection for DDL execution

Dockerfile如下：

FROM java:8
VOLUME /tmp
ADD hello-0.0.1-SNAPSHOT.jar app.jar
RUN bash -c 'touch /app.jar'
EXPOSE 8080
ENTRYPOINT ["java","-Djava.security.egd=file:/dev/./urandom","-jar","/app.jar"]

docker命令：

sudo docker build -t hello:1.1 .

udo docker run hello:1.1 -p 8080:8080 --name hello_cont01 --net=host

[bcsflilong]

在JDBC URL上添加?autoReconnect=true

[stacksoverflow]

docker容器内到DB的连接是否能ping通？

[亮神～]

是否是使用compose yml文件的方法启动的 mysql服务可能还没有起来 https://docs.docker.com/compose/startup-order/

[MXi4oyu]

跟docker没关，目测是你代码的问题，虽然不知道你代码写的啥，但是感觉数据库连接字符串配置错了。