Question

我是java的新手，我需要有关如何在我的Java应用程序项目中为JDBC创建连接池的帮助。我已经能够连接到我的数据库，但我的应用程序的性能很慢，因为我在每个帧上调用连接，就像我在youtube上的许多视频教程中看到的那样。

这就是我连接数据库的方式。我在我的大部分框架中调用了DBConnection.getConnectDB()等每个帧中的连接。

如何在netbeans中为java创建JDBC连接池。谢谢

DBCONNECT

public class DBConnection {


    public static Connection ConnectDB(){

        try{
            Class.forName("com.mysql.jdbc.Driver");
            Connection conn = DriverManager.getConnection("jdbc:mysql://server/db_name","user","pass");
            System.out.println("Connected");
            return conn;
        }
        catch(Exception ex){

            JOptionPane.showMessageDialog(null, ex);
            return null;
       }}     
}

更新

public static Connection ConnectDB(){


 HikariConfig config = new HikariConfig();

config.setJdbcUrl（ “JDBC：MySQL的：//本地主机：3306 /辛普森一家”）;

config.setUsername("username");
config.setPassword("pass");
config.addDataSourceProperty("cachePrepStmts", "true");
config.addDataSourceProperty("prepStmtCacheSize", "250");
config.addDataSourceProperty("prepStmtCacheSqlLimit", "2048");

HikariDataSource ds = new HikariDataSource(config);
    return (Connection) new HikariDataSource(config);

    }

}

控制台

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.
Exception in thread "AWT-EventQueue-0" com.zaxxer.hikari.pool.HikariPool$PoolInitializationException: Failed to initialize pool: Access denied for user 'qweqsbra_wagyingo'@'197.251.142.100' (using password: YES)
    at com.zaxxer.hikari.pool.HikariPool.throwPoolInitializationException(HikariPool.java:543)
    at com.zaxxer.hikari.pool.HikariPool.checkFailFast(HikariPool.java:535)
    at com.zaxxer.hikari.pool.HikariPool.<init>(HikariPool.java:111)
    at com.zaxxer.hikari.HikariDataSource.<init>(HikariDataSource.java:72)
    at wagyingohostel.DBConnection.DBConnection.ConnectDB(DBConnection.java:41)
    at wagyingohostel.LoginAndRegistration.Login.<init>(Login.java:34)
    at wagyingohostel.LoginAndRegistration.Login$4.run(Login.java:228)
    at java.awt.event.InvocationEvent.dispatch(InvocationEvent.java:311)
    at java.awt.EventQueue.dispatchEventImpl(EventQueue.java:756)
    at java.awt.EventQueue.access$500(EventQueue.java:97)
    at java.awt.EventQueue$3.run(EventQueue.java:709)
    at java.awt.EventQueue$3.run(EventQueue.java:703)
    at java.security.AccessController.doPrivileged(Native Method)
    at java.security.ProtectionDomain$JavaSecurityAccessImpl.doIntersectionPrivilege(ProtectionDomain.java:76)
    at java.awt.EventQueue.dispatchEvent(EventQueue.java:726)
    at java.awt.EventDispatchThread.pumpOneEventForFilters(EventDispatchThread.java:201)
    at java.awt.EventDispatchThread.pumpEventsForFilter(EventDispatchThread.java:116)
    at java.awt.EventDispatchThread.pumpEventsForHierarchy(EventDispatchThread.java:105)
    at java.awt.EventDispatchThread.pumpEvents(EventDispatchThread.java:101)
    at java.awt.EventDispatchThread.pumpEvents(EventDispatchThread.java:93)
    at java.awt.EventDispatchThread.run(EventDispatchThread.java:82)
Caused by: java.sql.SQLException: Access denied for user 'qweqsbra_wagyingo'@'197.251.142.100' (using password: YES)
    at com.mysql.jdbc.SQLError.createSQLException(SQLError.java:964)
    at com.mysql.jdbc.MysqlIO.checkErrorPacket(MysqlIO.java:3973)
    at com.mysql.jdbc.MysqlIO.checkErrorPacket(MysqlIO.java:3909)
    at com.mysql.jdbc.MysqlIO.checkErrorPacket(MysqlIO.java:873)
    at com.mysql.jdbc.MysqlIO.proceedHandshakeWithPluggableAuthentication(MysqlIO.java:1710)
    at com.mysql.jdbc.MysqlIO.doHandshake(MysqlIO.java:1226)
    at com.mysql.jdbc.ConnectionImpl.coreConnect(ConnectionImpl.java:2198)
    at com.mysql.jdbc.ConnectionImpl.connectOneTryOnly(ConnectionImpl.java:2229)
    at com.mysql.jdbc.ConnectionImpl.createNewIO(ConnectionImpl.java:2024)
    at com.mysql.jdbc.ConnectionImpl.<init>(ConnectionImpl.java:779)
    at com.mysql.jdbc.JDBC4Connection.<init>(JDBC4Connection.java:47)
    at sun.reflect.NativeConstructorAccessorImpl.newInstance0(Native Method)
    at sun.reflect.NativeConstructorAccessorImpl.newInstance(NativeConstructorAccessorImpl.java:62)
    at sun.reflect.DelegatingConstructorAccessorImpl.newInstance(DelegatingConstructorAccessorImpl.java:45)
    at java.lang.reflect.Constructor.newInstance(Constructor.java:423)
    at com.mysql.jdbc.Util.handleNewInstance(Util.java:425)
    at com.mysql.jdbc.ConnectionImpl.getInstance(ConnectionImpl.java:389)
    at com.mysql.jdbc.NonRegisteringDriver.connect(NonRegisteringDriver.java:330)
    at com.zaxxer.hikari.util.DriverDataSource.getConnection(DriverDataSource.java:112)
    at com.zaxxer.hikari.util.DriverDataSource.getConnection(DriverDataSource.java:118)
    at com.zaxxer.hikari.pool.PoolBase.newConnection(PoolBase.java:358)
    at com.zaxxer.hikari.pool.PoolBase.newPoolEntry(PoolBase.java:201)
    at com.zaxxer.hikari.pool.HikariPool.createPoolEntry(HikariPool.java:443)
    at com.zaxxer.hikari.pool.HikariPool.checkFailFast(HikariPool.java:514)
    ... 19 more
BUILD SUCCESSFUL (total time: 20 seconds)

Answer 1

如果您正在使用maven或gradle（您应该），您可以使用像HikariCP这样的池并创建一个像这样的jdbc连接池。

HikariConfig config = new HikariConfig();
config.setJdbcUrl("jdbc:mysql://localhost:3306/simpsons");
config.setUsername("bart");
config.setPassword("51mp50n");
config.addDataSourceProperty("cachePrepStmts", "true");
config.addDataSourceProperty("prepStmtCacheSize", "250");
config.addDataSourceProperty("prepStmtCacheSqlLimit", "2048");

HikariDataSource ds = new HikariDataSource(config);

以下是更详细的example configuring multiple hikaricp pools

Answer 2

您需要在Netbeans中为数据库连接池配置JNDI数据源。请按照以下URL中提到的步骤使用Netbeans ID创建连接池

https://dzone.com/articles/nb-class-glassfish-mysql-jdbc

用Java创建JDBC连接池

2 个答案: