如何使用MySQL的连接池优化数据库连接的性能

import java.sql.Connection;
import java.sql.DriverManager;
import java.sql.SQLException;
import java.util.ArrayList;
import java.util.List;

public class ConnectionPool {
    private String url;
    private String username;
    private String password;
    private List<Connection> connections;

    public ConnectionPool(String url, String username, String password, int maxConnections) {
        this.url = url;
        this.username = username;
        this.password = password;
        this.connections = new ArrayList<>();

        try {
            for (int i = 0; i < maxConnections; i++) {
                Connection connection = DriverManager.getConnection(url, username, password);
                connections.add(connection);
            }
        } catch (SQLException e) {
            e.printStackTrace();
        }
    }

    public synchronized Connection getConnection() {
        if (connections.isEmpty()) {
            try {
                wait(); // 如果连接池为空，则等待连接释放
            } catch (InterruptedException e) {
                e.printStackTrace();
            }
        }
        return connections.remove(0);
    }

    public synchronized void releaseConnection(Connection connection) {
        connections.add(connection);
        notifyAll(); // 释放连接，并通知等待的线程
    }
}

public class Example {
    public static void main(String[] args) {
        String url = "jdbc:mysql://localhost:3306/mydatabase";
        String username = "root";
        String password = "password";
        int maxConnections = 10;

        ConnectionPool connectionPool = new ConnectionPool(url, username, password, maxConnections);

        // 获取连接
        Connection connection = connectionPool.getConnection();

        // 执行查询操作
        // ...

        // 释放连接
        connectionPool.releaseConnection(connection);
    }
}