我用驱动<com.mysql.cj.jdbc.driver> ，但“junit test”不断导致错误</com.mysql.cj.jdbc.driver>

Question

version

mysql 8.0.18

java 1.8

spring 5.2.1.RELEASE

junit 4.12

pom.xml

<?xml version="1.0" encoding="UTF-8"?>
<project xmlns="http://maven.apache.org/POM/4.0.0"
         xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
         xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 http://maven.apache.org/xsd/maven-4.0.0.xsd">
    <modelVersion>4.0.0</modelVersion>
    <groupId>com.hj</groupId>
    <artifactId>groupboard</artifactId>
    <name>groupboard</name>
    <packaging>war</packaging>
    <version>1.0.0-BUILD-SNAPSHOT</version>

    <properties>
        <java-version>1.8</java-version>
        <org.springframework-version>5.2.1.RELEASE</org.springframework-version>
        <org.aspectj-version>1.9.4</org.aspectj-version>
        <org.slf4j-version>1.7.25</org.slf4j-version>
    </properties>

    <dependencies>
        <!-- Spring -->
        <dependency>
            <groupId>org.springframework</groupId>
            <artifactId>spring-context</artifactId>
            <version>${org.springframework-version}</version>
            <exclusions>
                <!-- Exclude Commons Logging in favor of SLF4j -->
                <exclusion>
                    <groupId>commons-logging</groupId>
                    <artifactId>commons-logging</artifactId>
                 </exclusion>
            </exclusions>
        </dependency>
        <dependency>
            <groupId>org.springframework</groupId>
            <artifactId>spring-webmvc</artifactId>
            <version>${org.springframework-version}</version>
        </dependency>
        <dependency>
            <groupId>org.springframework</groupId>
            <artifactId>spring-jdbc</artifactId>
            <version>${org.springframework-version}</version>
        </dependency>
        <dependency>
            <groupId>org.springframework</groupId>
            <artifactId>spring-test</artifactId>
            <version>${org.springframework-version}</version>
            <scope>test</scope>
        </dependency>


        <!-- AspectJ -->
        <dependency>
            <groupId>org.aspectj</groupId>
            <artifactId>aspectjrt</artifactId>
            <version>${org.aspectj-version}</version>
        </dependency>

        <!-- log4 -->
        <dependency>
            <groupId>org.bgee.log4jdbc-log4j2</groupId>
            <artifactId>log4jdbc-log4j2-jdbc4</artifactId>
            <version>1.16</version>
        </dependency>
        <!-- Logging -->
        <dependency>
            <groupId>org.slf4j</groupId>
            <artifactId>slf4j-api</artifactId>
            <version>${org.slf4j-version}</version>
        </dependency>
        <dependency>
            <groupId>org.slf4j</groupId>
            <artifactId>jcl-over-slf4j</artifactId>
            <version>${org.slf4j-version}</version>
            <scope>runtime</scope>
        </dependency>
        <dependency>
            <groupId>org.slf4j</groupId>
            <artifactId>slf4j-log4j12</artifactId>
            <version>${org.slf4j-version}</version>
            <scope>runtime</scope>
        </dependency>
        <dependency>
            <groupId>log4j</groupId>
            <artifactId>log4j</artifactId>
            <version>1.2.15</version>
            <exclusions>
                <exclusion>
                    <groupId>javax.mail</groupId>
                    <artifactId>mail</artifactId>
                </exclusion>
                <exclusion>
                    <groupId>javax.jms</groupId>
                    <artifactId>jms</artifactId>
                </exclusion>
                <exclusion>
                    <groupId>com.sun.jdmk</groupId>
                    <artifactId>jmxtools</artifactId>
                </exclusion>
                <exclusion>
                    <groupId>com.sun.jmx</groupId>
                    <artifactId>jmxri</artifactId>
                </exclusion>
            </exclusions>
            <scope>runtime</scope>
        </dependency>

        <!-- @Inject -->
        <dependency>
            <groupId>javax.inject</groupId>
            <artifactId>javax.inject</artifactId>
            <version>1</version>
        </dependency>

        <!-- Servlet -->
        <dependency>
            <groupId>javax.servlet</groupId>
            <artifactId>javax.servlet-api</artifactId>
            <version>3.1.0</version>
            <scope>provided</scope>
        </dependency>
        <dependency>
            <groupId>javax.servlet.jsp</groupId>
            <artifactId>javax.servlet.jsp-api</artifactId>
            <version>2.3.1</version>
            <scope>provided</scope>
        </dependency>
        <dependency>
            <groupId>javax.servlet</groupId>
            <artifactId>jstl</artifactId>
            <version>1.2</version>
        </dependency>

        <!-- https://mvnrepository.com/artifact/junit/junit -->
        <dependency>
            <groupId>junit</groupId>
            <artifactId>junit</artifactId>
            <version>4.12</version>
            <scope>test</scope>
        </dependency>


        <!-- mybatis -->
        <dependency>
            <groupId>org.mybatis</groupId>
            <artifactId>mybatis</artifactId>
            <version>3.5.3</version>
        </dependency>
        <dependency>
            <groupId>org.mybatis</groupId>
            <artifactId>mybatis-spring</artifactId>
            <version>2.0.3</version>
        </dependency>
        <dependency>
            <groupId>mysql</groupId>
            <artifactId>mysql-connector-java</artifactId>
            <version>8.0.18</version>
        </dependency>
        <dependency>
            <groupId>org.apache.commons</groupId>
            <artifactId>commons-dbcp2</artifactId>
            <version>2.7.0</version>
        </dependency>
        <dependency>
            <groupId>org.junit.jupiter</groupId>
            <artifactId>junit-jupiter</artifactId>
            <version>RELEASE</version>
            <scope>test</scope>
        </dependency>

    </dependencies>

    <build>
        <plugins>
            <plugin>
                <artifactId>maven-eclipse-plugin</artifactId>
                <version>2.9</version>
                <configuration>
                    <additionalProjectnatures>
                        <projectnature>org.springframework.ide.eclipse.core.springnature</projectnature>
                    </additionalProjectnatures>
                    <additionalBuildcommands>
                        <buildcommand>org.springframework.ide.eclipse.core.springbuilder</buildcommand>
                    </additionalBuildcommands>
                    <downloadSources>true</downloadSources>
                    <downloadJavadocs>true</downloadJavadocs>
                </configuration>
            </plugin>
            <plugin>
                <groupId>org.apache.maven.plugins</groupId>
                <artifactId>maven-compiler-plugin</artifactId>
                <version>3.8.1</version>
                <configuration>
                    <source>1.8</source>
                    <target>1.8</target>
                    <compilerArgument>-Xlint:all</compilerArgument>
                    <showWarnings>true</showWarnings>
                    <showDeprecation>true</showDeprecation>
                </configuration>
            </plugin>
            <plugin>
                <groupId>org.codehaus.mojo</groupId>
                <artifactId>exec-maven-plugin</artifactId>
                <version>1.6.0</version>
                <configuration>
                    <mainClass>org.test.int1.Main</mainClass>
                </configuration>
            </plugin>
        </plugins>
    </build>

</project>

/groupboard/src/test/java/com.hj.groupboard.MySQLConnectionTest

package com.hj.groupboard;

import org.junit.Test;

import java.sql.Connection;
import java.sql.DriverManager;


public class MySQLConnectionTest {

    private static final String DRIVER = "com.mysql.cj.jdbc.Driver";
    private static final String URL = "jdbc:mysql://localhost:3306/againdb?serverTimezone=UTC";
    private static final String USER = "admin";
    private static final String PASSWORD = "************";

    @Test
    public void testConnection() throws Exception {
        Class.forName(DRIVER);
        try(Connection connection = DriverManager.getConnection(URL, USER, PASSWORD)) {
            System.out.println(connection);
        } catch (Exception e) {
            e.printStackTrace();
        }
    }
}

this is my console image of junit. please click this link .

I think this log from 'junit'.

Loading class 'com.mysql.jdbc.Driver'. This is deprecated. The new driver class is 'com.mysql.cj.jdbc.Driver'. The driver is automatically registered via the SPI and manual loading of the driver class is generally unnecessary.

and I think this log from 'java console log'.

com.mysql.cj.jdbc.ConnectionImpl@4516af24

I think "java" has not returned error, but "junit" has returned error.

How do I fix that "junit" error or something.

Console log image

============================append======================================

Please find this picture of IDE image.

IDE image

This error cause on Class.forName("com.mysql.cj.jdbc.Driver"); , I think this means MySQLConnectionTest.java class dosent'n have a error, but maybe some library has a error.

Now I want to find how to fix or change the library.

And many thanks about everyone's help of this fix. if I find solve this probleam, then I update this article.

Answer 1

I believe your issue resides on your maven's plugin configuration. I ran the test manually, with the following code and everything seems to work. Nonetheless, the driver warning shouldn't cause any error.

public class Main {

    public static void main(String[] args) {
        JUnitCore junit = new JUnitCore();
        junit.run(MySQLConnectionTest.class);
    }
}

I am running this class inside the test folder, using the following directory structure.

src/
   test/
       java/
           Main.java
           MySQLConnectionTest.java

Answer 2

That error causing by log4jdbc , that is logger library.

log4jdbc v1.12 is using 'com.mysql.jdbc.Driver' , not 'com.mysql.cj.jdbc.Driver' .

https://github.com/arthurblake/log4jdbc/pull/88/commits/287f55a8a839a42e95e20788d80d29f2d995b6a1

But 'log4jdbc' library dose not updated, since 2013, And that dose not fixed that issue.

In conclusion, 'log4jdbc' cannot using with MySQL 5.x or later .

So I think I need to find something another logger library.