addGap(18,18,18) .addGroup(layout.createParallelGroup(javax.swing.GroupLayout.Alignment.LEADING,false) .addComponent(LBL_密码,javax.swing.GroupLayout.DEFAULT_大小,30,Short.MAX_值) .addComponent(FLD_密码)) .addPreferredGap(javax.swing.LayoutStyle.ComponentPlacement.RELATED,86,Short.MAX_值) .addComponent(LBL_错误,javax.swing.GroupLayout.PREFERRED_大小,35,javax.swing.GroupLayout.PREFERRED_大小) .addGap(18,18,18) .addGroup(layout.createParallelGroup(javax.swing.GroupLayout.Alignment.BASELINE) .addComponent(BTN_登录,javax.swing.GroupLayout.PREFERRED_大小,32,javax.swing.GroupLayout.PREFERRED_大小) .addComponent(BTN_取消,javax.swing.GroupLayout.PREFERRED_大小,32,javax.swing.GroupLayout.PREFERRED_大小)) .addContainerGap()) ); setSize(新java.awt.Dimension(416339)); setLocationRelativeTo(空); }// 私有void BTN_CancelActionPerformed(java.awt.event.ActionEvent evt){ 这个。dispose(); } 私有void BTN_LoginActionPerformed(java.awt.event.ActionEvent evt){ 字符串STR_UserID=FLD_UserID.getText(); String STR_Password=新字符串(FLD_Password.getPassword()); validateUser(STR_用户标识、STR_密码); if(validateUser(STR_用户标识、STR_密码)){ GUI_Main GUI_Main=新GUI_Main(); GUI_Main.setExtendedState(JFrame.MAXIMIZED_两者); GUI_Main.设置未装饰(真实); GUI_Main.setVisible(true); 这个。dispose(); } 否则{ FLD_UserID.setText(“”); FLD_Password.setText(“”); LBL_Error.setText(“无效的登录凭据!”); } } private void fldu PasswordKeyPressed(java.awt.event.KeyEvent evt){ if(evt.getKeyCode()==KeyEvent.VK_ENTER){ BTN_Login.doClick(); } } /** *@param指定命令行参数 */ 公共静态void main(字符串参数[]){ /*设置Nimbus的外观和感觉*/ // /*如果Nimbus(在JavaSE6中引入)不可用,请使用默认的外观。 *详情请参阅http://download.oracle.com/javase/tutorial/uiswing/lookandfeel/plaf.html */ 试一试{ for(javax.swing.UIManager.LookAndFeelInfo:javax.swing.UIManager.getInstalledLookAndFeels()){ if(“Nimbus”.equals(info.getName())){ setLookAndFeel(info.getClassName()); 打破 } } }捕获(ClassNotFoundException ex){ getLogger(GUI_Launcher.class.getName()).log(java.util.logging.Level.severy,null,ex); }catch(实例化异常){ getLogger(GUI_Launcher.class.getName()).log(java.util.logging.Level.severy,null,ex); }捕获(非法访问例外){ getLogger(GUI_Launcher.class.getName()).log(java.util.logging.Level.severy,null,ex); }catch(javax.swing.UnsupportedLookAndFeelException ex){ getLogger(GUI_Launcher.class.getName()).log(java.util.logging.Level.severy,null,ex); } // /*创建并显示表单*/ invokeLater(new Runnable()){ 公开募捐{ 新GUI_启动器().setVisible(true); } }); } //变量声明-不修改 私有javax.swing.JButton BTN_Cancel; 私有javax.swing.JButton BTN_登录; 私有javax.swing.JPasswordField FLD_密码; 私有javax.swing.JTextField FLD_UserID; 私有javax.swing.JLabel LBL_错误; 私有javax.swing.JLabel LBL_密码; 私有javax.swing.JLabel LBL_用户标识; //变量结束声明
我对Java相当陌生,因此非常感谢提供一些示例代码和解释。谢谢。在询问我的java向导朋友后解决了这个问题。将以下代码添加到按钮操作处理程序中:addGap(18,18,18) .addGroup(layout.createParallelGroup(javax.swing.GroupLayout.Alignment.LEADING,false) .addComponent(LBL_密码,javax.swing.GroupLayout.DEFAULT_大小,30,Short.MAX_值) .addComponent(FLD_密码)) .addPreferredGap(javax.swing.LayoutStyle.ComponentPlacement.RELATED,86,Short.MAX_值) .addComponent(LBL_错误,javax.swing.GroupLayout.PREFERRED_大小,35,javax.swing.GroupLayout.PREFERRED_大小) .addGap(18,18,18) .addGroup(layout.createParallelGroup(javax.swing.GroupLayout.Alignment.BASELINE) .addComponent(BTN_登录,javax.swing.GroupLayout.PREFERRED_大小,32,javax.swing.GroupLayout.PREFERRED_大小) .addComponent(BTN_取消,javax.swing.GroupLayout.PREFERRED_大小,32,javax.swing.GroupLayout.PREFERRED_大小)) .addContainerGap()) ); setSize(新java.awt.Dimension(416339)); setLocationRelativeTo(空); }// 私有void BTN_CancelActionPerformed(java.awt.event.ActionEvent evt){ 这个。dispose(); } 私有void BTN_LoginActionPerformed(java.awt.event.ActionEvent evt){ 字符串STR_UserID=FLD_UserID.getText(); String STR_Password=新字符串(FLD_Password.getPassword()); validateUser(STR_用户标识、STR_密码); if(validateUser(STR_用户标识、STR_密码)){ GUI_Main GUI_Main=新GUI_Main(); GUI_Main.setExtendedState(JFrame.MAXIMIZED_两者); GUI_Main.设置未装饰(真实); GUI_Main.setVisible(true); 这个。dispose(); } 否则{ FLD_UserID.setText(“”); FLD_Password.setText(“”); LBL_Error.setText(“无效的登录凭据!”); } } private void fldu PasswordKeyPressed(java.awt.event.KeyEvent evt){ if(evt.getKeyCode()==KeyEvent.VK_ENTER){ BTN_Login.doClick(); } } /** *@param指定命令行参数 */ 公共静态void main(字符串参数[]){ /*设置Nimbus的外观和感觉*/ // /*如果Nimbus(在JavaSE6中引入)不可用,请使用默认的外观。 *详情请参阅http://download.oracle.com/javase/tutorial/uiswing/lookandfeel/plaf.html */ 试一试{ for(javax.swing.UIManager.LookAndFeelInfo:javax.swing.UIManager.getInstalledLookAndFeels()){ if(“Nimbus”.equals(info.getName())){ setLookAndFeel(info.getClassName()); 打破 } } }捕获(ClassNotFoundException ex){ getLogger(GUI_Launcher.class.getName()).log(java.util.logging.Level.severy,null,ex); }catch(实例化异常){ getLogger(GUI_Launcher.class.getName()).log(java.util.logging.Level.severy,null,ex); }捕获(非法访问例外){ getLogger(GUI_Launcher.class.getName()).log(java.util.logging.Level.severy,null,ex); }catch(javax.swing.UnsupportedLookAndFeelException ex){ getLogger(GUI_Launcher.class.getName()).log(java.util.logging.Level.severy,null,ex); } // /*创建并显示表单*/ invokeLater(new Runnable()){ 公开募捐{ 新GUI_启动器().setVisible(true); } }); } //变量声明-不修改 私有javax.swing.JButton BTN_Cancel; 私有javax.swing.JButton BTN_登录; 私有javax.swing.JPasswordField FLD_密码; 私有javax.swing.JTextField FLD_UserID; 私有javax.swing.JLabel LBL_错误; 私有javax.swing.JLabel LBL_密码; 私有javax.swing.JLabel LBL_用户标识; //变量结束声明,java,database,swing,Java,Database,Swing,我对Java相当陌生,因此非常感谢提供一些示例代码和解释。谢谢。在询问我的java向导朋友后解决了这个问题。将以下代码添加到按钮操作处理程序中: try { PreparedStatement STMT_GetCurrentUser = getConnection().prepareStatement("SELECT * FROM Employees WHERE [UserID]='"+STR_UserID+"'"); ResultSet RSET_GetCurr
try {
PreparedStatement STMT_GetCurrentUser = getConnection().prepareStatement("SELECT * FROM Employees WHERE [UserID]='"+STR_UserID+"'");
ResultSet RSET_GetCurrentUser = STMT_GetCurrentUser.executeQuery();
if (RSET_GetCurrentUser.next()){
SYS_Vars.SYS_CurrentUser = RSET_GetCurrentUser.getString(2);
}
} catch (SQLException EX_1) {
EX_1.printStackTrace();
} catch (ClassNotFoundException EX_2) {
EX_2.printStackTrace();
}
回想起来,我显然很愚蠢,因为我没有意识到我必须使用getConnection()方法而不是connection,但考虑到我的Java背景,我并不感到惊讶。“因此,非常感谢提供一些示例代码和解释。”互联网上有很多“query a DB”Java示例。请搜索它们并实际尝试一些东西。如果你有具体问题,请回复我们。安德鲁,到目前为止,我已经花了好几天的时间在互联网上搜索,测试来自不同网站的示例,但都没有结果。我不会浪费人们的时间在这里问我是否需要。“花了几天时间在互联网上搜索”使用了什么搜索词?发现的3个最有帮助的例子是什么,为什么没有帮助?
try {
PreparedStatement STMT_GetCurrentUser = getConnection().prepareStatement("SELECT * FROM Employees WHERE [UserID]='"+STR_UserID+"'");
ResultSet RSET_GetCurrentUser = STMT_GetCurrentUser.executeQuery();
if (RSET_GetCurrentUser.next()){
SYS_Vars.SYS_CurrentUser = RSET_GetCurrentUser.getString(2);
}
} catch (SQLException EX_1) {
EX_1.printStackTrace();
} catch (ClassNotFoundException EX_2) {
EX_2.printStackTrace();
}