如何将SQL连接传递给动作监听器。我想有一个无限循环,它会休眠100毫秒。循环的每次迭代均假定查询数据库。摇摆计时器是执行此操作的最佳方法吗?如果是这样,我如何将连接传递给动作监听器。如果不是这样,有人可以建议如何做到这一点。非常感谢。
码:
public static void main(String[] args) throws InterruptedException {
EventQueue.invokeLater(new Runnable() {
@Override
public void run() {
try {
AdminManager frame = new AdminManager();
frame.setVisible(true);
} catch (Exception e) {
e.printStackTrace();
}
}
});
BoneCP connectionPool = null;
Connection connection = null;
try {
Class.forName("com.mysql.jdbc.Driver");
} catch (Exception e) {
e.printStackTrace();
return;
}
try {
// setup the connection pool
BoneCPConfig config = new BoneCPConfig();
config.setJdbcUrl("jdbc:mysql://192.162.0.0");
config.setUsername("root");
config.setPassword("");
connectionPool = new BoneCP(config); // setup the connection pool
connection = connectionPool.getConnection(); // fetch a connection
if (connection != null){
System.out.println("Connection successful!");
}
} catch (SQLException e) {
e.printStackTrace();
} finally {
if (connection != null) {
try {
connection.close();
} catch (SQLException e) {
e.printStackTrace();
}
}
}
// Define listner
ActionListener taskPerformer = new ActionListener() {
@Override
public void actionPerformed(ActionEvent evt) {
//...Perform a task...
String sql = "SELECT * table;";
Statement st = connection.createStatement();
ResultSet rs = st.executeQuery(sql);
while(rs.next()) {
String symbol = rs.getString("name");
System.out.println(symbol);
}
}
};
Timer timer = new Timer( 100 , taskPerformer);
timer.setRepeats(true);
timer.start();
Thread.sleep(1000);
//connectionPool.shutdown(); // shutdown connection pool.
}
最佳答案
不要使用javax.swing.Timer
类来定期执行非swing任务。而是使用ScheduleExecutorService
,
ScheduledExecutorService exec = Executors.newSingleThreadScheduledExecutor();
exec.schedule(new Runnable(){
@Override
public void run(){
// query database
}
}, 0, 100, TimeUnit.MILLISECONDS);