在Java中用mysql查询连接两个数据库？

String url1 = "jdbc:mysql://localhost:3306/db1";
String username1 = "root";
String password1 = "password";

Connection conn1 = DriverManager.getConnection(url1, username1, password1);

String url2 = "jdbc:mysql://localhost:3306/db2";
String username2 = "root";
String password2 = "password";

Connection conn2 = DriverManager.getConnection(url2, username2, password2);

Statement stmt1 = conn1.createStatement();
ResultSet rs1 = stmt1.executeQuery("SELECT * FROM table1");

Statement stmt2 = conn2.createStatement();
ResultSet rs2 = stmt2.executeQuery("SELECT * FROM table2");

while (rs1.next()) {
    // 处理第一个数据库查询结果
}

while (rs2.next()) {
    // 处理第二个数据库查询结果
}

rs1.close();
stmt1.close();
conn1.close();

rs2.close();
stmt2.close();
conn2.close();