I am currently learning more about implementing JDBC and using databases in a Spring Boot webapp, and I encountered the following Stack Trace written in the bottom of the post.
I have created a simple Employee model, and I am trying to execute some database code on the same class which my main() lies in. The model and the main class are the only two java files existing in this whole project. I am trying to implement the following run() code that overrides the one from the interface, CommandLineRunner, but I do not get the logs that should come after log.info("Part A:"):
log.info("Part A:")
employees.forEach(employee -> {log.info(employee.toString());
log.info("part a");});
--Things I noticed:
I noticed that the last line of the log before the stack trace starts comes from: "Thread-1" instead of "main". I think that means that a thread from somewhere other than the main encountered an error and closed connection before when it should close normally.
Also, I think that because HikariPool closed before "peer's close_notify", which I presume that it refers to the normal closure of HikariPool, I am not able to see the final bit of logging that I have kept trying to procure. The final bit of logging that I want to see is the logging of the employee that has become inserted into my database.
The final bit of logging that I want to see should be procured from this line of code:
employees.forEach(employee -> {log.info(employee.toString());
log.info("part a");});
--Things to note:
Because of this line in the log, I thought I would see the employee inserted into my database, but when I queried directly on MySQL Command Line Client, it returned an empty set:
2018-11-03 21:08:35.362 INFO 2408 --- [ main] c.j.jdbctest1.JdbcTest1Application : rows affected: 1
I don't understand why a row has been affected when nothing has been inserted into the database.
The stacktrace and logs: (The stacktrace pasted below actually repeats itself several more times but I cut it off for brevity.)
2018-11-03 21:08:32.997 INFO 2408 --- [ main] c.j.jdbctest1.JdbcTest1Application : Starting JdbcTest1Application on KitKat with PID 2408 (C:\Users\Nano\Downloads\jdbc-test1\jdbc-test1\target\classes started by Nano in C:\Users\Nano\Downloads\jdbc-test1\jdbc-test1)
2018-11-03 21:08:33.003 INFO 2408 --- [ main] c.j.jdbctest1.JdbcTest1Application : No active profile set, falling back to default profiles: default
2018-11-03 21:08:33.770 INFO 2408 --- [ main] c.j.jdbctest1.JdbcTest1Application : Started JdbcTest1Application in 1.024 seconds (JVM running for 1.778)
2018-11-03 21:08:33.770 INFO 2408 --- [ main] c.j.jdbctest1.JdbcTest1Application : Creating tables
2018-11-03 21:08:33.770 INFO 2408 --- [ main] com.zaxxer.hikari.HikariDataSource : HikariPool-1 - Starting...
2018-11-03 21:08:34.082 INFO 2408 --- [ main] com.zaxxer.hikari.HikariDataSource : HikariPool-1 - Start completed.
2018-11-03 21:08:35.135 INFO 2408 --- [ main] c.j.jdbctest1.JdbcTest1Application : Inserting Baggins Hopkins
2018-11-03 21:08:35.362 INFO 2408 --- [ main] c.j.jdbctest1.JdbcTest1Application : rows affected: 1
2018-11-03 21:08:35.362 INFO 2408 --- [ main] c.j.jdbctest1.JdbcTest1Application : Querying for employee
2018-11-03 21:08:36.065 INFO 2408 --- [ main] c.j.jdbctest1.JdbcTest1Application : Part A:
2018-11-03 21:08:36.065 INFO 2408 --- [ Thread-1] com.zaxxer.hikari.HikariDataSource : HikariPool-1 - Shutdown initiated...
Sat Nov 03 21:08:36 KST 2018 WARN: Caught while disconnecting...
EXCEPTION STACK TRACE:
** BEGIN NESTED EXCEPTION **
javax.net.ssl.SSLException
MESSAGE: closing inbound before receiving peer's close_notify
STACKTRACE:
javax.net.ssl.SSLException: closing inbound before receiving peer's close_notify
at java.base/sun.security.ssl.Alert.createSSLException(Alert.java:129)
at java.base/sun.security.ssl.Alert.createSSLException(Alert.java:117)
at java.base/sun.security.ssl.TransportContext.fatal(TransportContext.java:308)
at java.base/sun.security.ssl.TransportContext.fatal(TransportContext.java:264)
at java.base/sun.security.ssl.TransportContext.fatal(TransportContext.java:255)
at java.base/sun.security.ssl.SSLSocketImpl.shutdownInput(SSLSocketImpl.java:645)
at java.base/sun.security.ssl.SSLSocketImpl.shutdownInput(SSLSocketImpl.java:624)
at com.mysql.cj.protocol.a.NativeProtocol.quit(NativeProtocol.java:1312)
at com.mysql.cj.NativeSession.quit(NativeSession.java:182)
at com.mysql.cj.jdbc.ConnectionImpl.realClose(ConnectionImpl.java:1750)
at com.mysql.cj.jdbc.ConnectionImpl.close(ConnectionImpl.java:720)
at com.zaxxer.hikari.pool.PoolBase.quietlyCloseConnection(PoolBase.java:135)
at com.zaxxer.hikari.pool.HikariPool.lambda$closeConnection$1(HikariPool.java:441)
at java.base/java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1128)
at java.base/java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:628)
at java.base/java.lang.Thread.run(Thread.java:834)
** END NESTED EXCEPTION **
The Java Code:
@SpringBootApplication
public class JdbcTest1Application implements CommandLineRunner {
private static final Logger log = LoggerFactory.getLogger(JdbcTest1Application.class);
@Autowired
JdbcTemplate jdbcTemplate;
public static void main(String[] args) {
SpringApplication.run(JdbcTest1Application.class, args);
}
@Override
public void run(String... args) throws Exception {
log.info("Creating tables");
jdbcTemplate.execute("DROP TABLE IF EXISTS employees");
jdbcTemplate.execute("CREATE TABLE employees (emp_id int, name varchar(100), role varchar(100), status varchar(100))");
log.info("Inserting Baggins Hopkins");
int rowsAffected = jdbcTemplate.update("INSERT INTO EMPLOYEE(EMP_ID, NAME, ROLE, STATUS)"
+ " VALUES(1,'Baggins Hopkins','thief','WORKING')");
log.info("rows affected: "+ Integer.toString(rowsAffected));
log.info("Querying for employee");
String sql = "SELECT emp_id,name,role,status FROM employees";
List<Employee> employees = jdbcTemplate.query(sql,(rs, rowNum)->
new Employee(rs.getInt("emp_id"), rs.getString("name"),
rs.getString("role"),Status.valueOf(rs.getString("status"))));
log.info("Part A:");
employees.forEach(employee -> {log.info(employee.toString());
log.info("part a");});
}
}
Also just in case this matters, I pasted this code from application.properties:
spring.datasource.url=jdbc:mysql://localhost:3306/employee_database
spring.datasource.username=employee
spring.datasource.password=employee
spring.datasource.driver-class-name=com.mysql.cj.jdbc.Driver
To solve this problem, it took me about three days.
(Edit: This is a workaround for testing and not actually a solution.)
At first, I started solving the problem from trying to configure my own SSL for mysql, and I spent quite a few hours on that. Too much time had passed until I realized configuring it had to do with Cmake and C++, which made me give up. It was very frustrating. However I did not give up and tried to disable SSL entirely through a method that hasn't been found. And I eventually did find the method. Here it is:
Open up the MySQL installer again, and reconfigure the MySQL Server settings. When you get there you will see this screen:
The screen that you should get to
You might get some errors when reaching the final stage of the reconfiguration:
I had problems at the final stage I had no idea how to fix so I uninstalled MySQL altogether. I use windows. I deleted the MySQL project root directory from Program Files to uninstall MySQL. I also deleted the databases saved in Program Data (a hidden folder in the C Drive) because I wanted to start afresh(WARNING: this will delete all your previously saved data!). Uninstalling MySQL from the control panel might not be enough to completely erase MySQL from your computer.
You might not see ProgramData in the C Drive. That is because it is a hidden folder. In order to see hidden folders:
search for folder options in the control panel.
Go to view.
Under 'Advanced settings' and under 'Hidden files and folders' of that, click "Show hidden files, folders, and drives."
ssl=0
Then save. It should work now.
References:
