Java JDBC和多線程是Java編程中非常重要的兩個概念，下面將分別介紹它們的基本概念和用法。

Java JDBC是Java提供的連接各種關系型數據庫的API，可以通過Java JDBC連接數據庫并執行各種數據庫操作語句。

import java.sql.*;
public class JDBCTest {
public static void main(String[] args) {
Connection conn = null;
PreparedStatement ps = null;
ResultSet rs = null;
try {
Class.forName("com.mysql.jdbc.Driver");
conn = DriverManager.getConnection("jdbc:mysql://localhost:3306/test", "root", "password");
String sql = "select * from users";
ps = conn.prepareStatement(sql);
rs = ps.executeQuery();
while (rs.next()) {
System.out.println(rs.getString("name") + " " + rs.getInt("age"));
}
} catch (ClassNotFoundException | SQLException e) {
e.printStackTrace();
} finally {
try {
if (rs != null)
rs.close();
if (ps != null)
ps.close();
if (conn != null)
conn.close();
} catch (SQLException e) {
e.printStackTrace();
}
}
}
}

多線程是Java編程中用于提高程序并發性和響應速度的重要工具。

public class ThreadTest {
public static void main(String[] args) {
Thread thread1 = new Thread(new PrintThread(1));
Thread thread2 = new Thread(new PrintThread(2));
thread1.start();
thread2.start();
}
static class PrintThread implements Runnable {
private int id;
public PrintThread(int id) {
this.id = id;
}
@Override
public void run() {
for (int i = 0; i< 10; i++) {
System.out.println("Thread " + id + " count " + i);
try {
Thread.sleep(1000);
} catch (InterruptedException e) {
e.printStackTrace();
}
}
}
}
}

以上就是Java JDBC和多線程的基本介紹和使用方法。