尝试statemet.executeUpdate()在我的代码中执行时,我收到以下错误:
Local variable statement defined in an enclosing scope must be final or effectively final.
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到目前为止这是我的代码:
import java.sql.Connection;
import java.sql.DriverManager;
import java.sql.ResultSet;
import java.sql.SQLException;
import java.sql.Statement;.
import org.eclipse.swt.SWT;
import org.eclipse.swt.events.MouseAdapter;
import org.eclipse.swt.events.MouseEvent;
import org.eclipse.swt.widgets.Button;
import org.eclipse.swt.widgets.Display;
import org.eclipse.swt.widgets.Label;
import org.eclipse.swt.widgets.Shell;
import org.eclipse.swt.widgets.Text;
public class a1 {
protected Shell shell;
private Text text;
private Text text_1;
private Text text_2;
private Text text_3;
/**
* Launch the application.
* @param args
*/
public static void main(String[] args) {
try { …Run Code Online (Sandbox Code Playgroud) 使用MongoDB createIndex()和ensureIndex()Java 之间有什么区别?我用Google搜索了这个,但没有得到满意的答案.
我正在使用 PubNub (GO SDK) 发布/订阅服务来接收消息,但即使我能够google.com从容器内部ping 通,我也没有收到任何消息。
在 Pubnub 日志中,每次我的程序尝试连接到源(Pubnub 服务器)时,我都会收到“拨号 tcp:i/o 超时”错误。我猜这是由于主机或容器中的 Internet 连接速度较慢。
我应该怎么做才能解决这个错误?
我想让程序通过add和shift方法将两个数相乘.我已经在sbcl lisp中编写了这段代码.
(defun calculator (num1 num2)
(write-line "In the function")
(let ((res 0))
(loop for lpr from 0 to 63
do (let ((end-bit (logand num2 1)))
(format t "res is : ~a. ~%" num2)
(if (= end-bit 1)
(+ res num1))
(ash num2 -1)
(ash num1 1)
(format t "after ash ~a ~%"num2)))
(format t "result is ~a.~%" res)))
(let ((num1 (progn
(write-line "Enter first number: ")
(finish-output)
(read)))
(num2 (progn
(write-line "Enter second number: ")
(finish-output)
(read))))
(if (or …Run Code Online (Sandbox Code Playgroud)