If change MySQL JDBC driver from 5.1.38
to 6.0.2
I get the following exception
java.sql.SQLNonTransientConnectionException: CLIENT_PLUG
This sounds like a regression. Was there a particular reason to switch to 6.0.2? If not, I'd revert back to 5.1.38 and give 6.x a shot after three months to let folks at MySQL to stabilize the driver.
It may be due to mysql version is too old so you need to do 3 changes in that case: in application.properties do first 2 changes:
spring.jpa.properties.hibernate.dialect=org.hibernate.dialect.MySQL5Dialect
spring.datasource.driver-class-name=com.mysql.jdbc.Driver
Do changes in pom.xml file in dependency of mysql-connector-java replace scope tag to the version tag and in version write your mysql version like 5.1
I resolve this problem by removing mysql version in pom.
<dependency>
<groupId>mysql</groupId>
<artifactId>mysql-connector-java</artifactId>
</dependency>
I had the same issue and I resolved by changing the parent tag version from 2.1.1.RELEASE to 2.0.0.RELEASE
from
<parent>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-starter-parent</artifactId>
<version>2.1.1.RELEASE</version>
<relativePath/> <!-- lookup parent from repository -->
</parent>
to
<parent>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-starter-parent</artifactId>
<version>2.0.0.RELEASE</version>
<relativePath/> <!-- lookup parent from repository -->
</parent>
It seems new versions of mysql connector (from 6 on) are not compatible with old version of the DBMS mysql(below 5.6). So in order to solve your problem, if you make an update of mysql connector, try to do the same with the DBMS. Actually I had the same issu with mysql connector 8.0.13 and the DBMS msql 5.1.... I solved it by moving the DBMS to 5.6.17
Use Maven depandency
###pom.xml
<dependency>
<groupId>mysql</groupId>
<artifactId>mysql-connector-java</artifactId>
<version>5.1.37</version>
</dependency>
##application.properties
server.port=9092
jwt.secret=javainuse
spring.datasource.url=jdbc:mysql://localhost:3306/hospital
spring.datasource.username=root
spring.datasource.password=root
spring.datasource.driver-class-name= com.mysql.jdbc.Driver
spring.datasource.platform=mysql
#spring.jpa.hibernate.ddl-auto=create-drop
spring.jpa.properties.hibernate.dialect= org.hibernate.dialect.MySQL5InnoDBDialect
spring.jpa.hibernate.ddl-auto= update
#spring.jpa.properties.hibernate.dialect= org.hibernate.dialect.MySQL5InnoDBDialect