日志记录出错，搞毛啊...

Bruce

"E:\Program Files\OpenJDK\jdk-13.0.1\bin\java.exe" --enable-preview "-javaagent:E:\Program Files\JetBrains\IntelliJ IDEA Community Edition 2019.2.4\lib\idea_rt.jar=4413:E:\Program Files\JetBrains\IntelliJ IDEA Community Edition 2019.2.4\bin" -Dfile.encoding=UTF-8 -classpath F:\Intellij-workspace\JDBC\target\classes;C:\Users\11479.m2\repository\com\zaxxer\HikariCP\3.4.1\HikariCP-3.4.1.jar;C:\Users\11479.m2\repository\org\slf4j\slf4j-api\1.7.25\slf4j-api-1.7.25.jar;C:\Users\11479.m2\repository\mysql\mysql-connector-java\8.0.18\mysql-connector-java-8.0.18.jar;C:\Users\11479.m2\repository\com\google\protobuf\protobuf-java\3.6.1\protobuf-java-3.6.1.jar com.bk.jdbc.test.ConnTest
SLF4J: Failed to load class "org.slf4j.impl.StaticLoggerBinder".
SLF4J: Defaulting to no-operation (NOP) logger implementation
SLF4J: See http://www.slf4j.org/codes.html#StaticLoggerBinder for further details.
Connection established.

Process finished with exit code 0

用OpenJDK 13编译，Maven 解决依赖

Maven的配置是

<?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>BKTech</groupId>
    <artifactId>JDBC</artifactId>
    <version>1.0-SNAPSHOT</version>

    <dependencies>

        <!-- https://mvnrepository.com/artifact/com.zaxxer/HikariCP -->
        <dependency>
            <groupId>com.zaxxer</groupId>
            <artifactId>HikariCP</artifactId>
            <version>3.4.1</version>
        </dependency>

        <!-- https://mvnrepository.com/artifact/mysql/mysql-connector-java -->
        <dependency>
            <groupId>mysql</groupId>
            <artifactId>mysql-connector-java</artifactId>
            <version>8.0.18</version>
        </dependency>

    </dependencies>

    <build>
        <plugins>
            <plugin>
                <groupId>org.apache.maven.plugins</groupId>
                <artifactId>maven-compiler-plugin</artifactId>
                <configuration>
                    <source>13.0.1</source>
                    <target>13.0.1</target>
                    <compilerArgs>--enable-preview</compilerArgs>
                    <encoding>UTF-8</encoding>
                </configuration>
            </plugin>
        </plugins>
    </build>

</project>

DBUtil的代码是

package com.bk.jdbc.util;

import com.zaxxer.hikari.HikariConfig;
import com.zaxxer.hikari.HikariDataSource;

import javax.sql.DataSource;
import java.sql.Connection;
import java.sql.SQLException;

public class DBUtil {
    /*
     * load DB driver
     */
//    static {
//        try {
//            Class.forName("com.mysql.jdbc.Driver");
//        }catch (ClassNotFoundException e) {
//            System.out.println("Failed to load DB driver!");
//        }
//    }
    /*
     * establish connection
     */
    private static DataSource ds;

    static {
        try {
            HikariConfig cfg=new HikariConfig("./conf/bruce.conf");
            ds=new HikariDataSource(cfg);
        } catch (Exception e) {
            e.printStackTrace();
        }
    }
    public static Connection getConn() throws SQLException {
        return ds.getConnection();
    }
    /*
     * close connection
     */
    public static void closeConn(Connection conn) {
        try {
            conn.close();
        }catch (SQLException e) {
            e.printStackTrace();
        }
    }
}

虽然只是几条warning，但是每次连接数据库的时候都提示，很烦啊

Bruce

顺便说下，ConnTest的代码是

package com.bk.jdbc.test;

import com.bk.jdbc.util.DBUtil;

import java.sql.Connection;
import java.sql.SQLException;

public class ConnTest {

    public static void main(String[] args) {
        Connection conn=null;
        try{
            conn= DBUtil.getConn();
            System.out.println("Connection established.");
        }catch (SQLException e) {
            e.printStackTrace();
        }finally {
            DBUtil.closeConn(conn);
        }
    }
}

Bruce

解决了...用Maven再添加一个slf4j-jdk14的依赖就行...

        <dependency>
            <groupId>org.slf4j</groupId>
            <artifactId>slf4j-jdk14</artifactId>
            <version>1.7.25</version>
        </dependency>

"E:\Program Files\OpenJDK\jdk-13.0.1\bin\java.exe" --enable-preview "-javaagent:E:\Program Files\JetBrains\IntelliJ IDEA Community Edition 2019.2.4\lib\idea_rt.jar=5980:E:\Program Files\JetBrains\IntelliJ IDEA Community Edition 2019.2.4\bin" -Dfile.encoding=UTF-8 -classpath F:\Intellij-workspace\JDBC\target\classes;C:\Users\11479.m2\repository\com\zaxxer\HikariCP\3.4.1\HikariCP-3.4.1.jar;C:\Users\11479.m2\repository\org\slf4j\slf4j-api\1.7.25\slf4j-api-1.7.25.jar;C:\Users\11479.m2\repository\mysql\mysql-connector-java\8.0.18\mysql-connector-java-8.0.18.jar;C:\Users\11479.m2\repository\com\google\protobuf\protobuf-java\3.6.1\protobuf-java-3.6.1.jar;C:\Users\11479.m2\repository\org\slf4j\slf4j-jdk14\1.7.25\slf4j-jdk14-1.7.25.jar com.bk.jdbc.test.ConnTest
11月 19, 2019 6:41:18 下午 com.zaxxer.hikari.HikariDataSource <init>
信息: HikariPool-1 - Starting...
11月 19, 2019 6:41:19 下午 com.zaxxer.hikari.HikariDataSource <init>
信息: HikariPool-1 - Start completed.
Connection established.

Process finished with exit code 0