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rs.getString("name").trim()
.....
//处理事件
if(e.getSource() == sureBt){
String name = textName.getText(); //得到的都是""空字符串,而不是null
String passwd = new String(textPassword.getPassword());
boolean pass=this.isPass(name,passwd);
if(pass)
JOptionPane.showMessageDialog(null,"恭喜你,登录成功!","登录成功",JOptionPane.INFORMATION_MESSAGE);
else{
JOptionPane.showMessageDialog(null,"对不起,帐号或密码错误,请重新输入","信息错误",JOptionPane.WARNING_MESSAGE);
textPassword.setText("");
textName.requestFocusInWindow();
}
}
.....
//isPass方法,判断是否存在合法的账号及密码
public boolean isPass(String name,String passwd){
Connection conn = null;
Statement stmt=null;
String sql=null;
ResultSet rs=null;
boolean pass=false;
try{
//取得一个与MySQL的连接
//public static Connection getMySQLConn(String dbName,String user,String userPassword)是我在外部定义的一个静态方法
conn=DBConnection.getMySQLConn("book","root","123");
stmt=conn.createStatement(ResultSet.TYPE_SCROLL_SENSITIVE,ResultSet.CONCUR_UPDATABLE);
sql="SELECT * FROM user WHERE name='"+name+"' AND password='"+passwd+"'";
rs = stmt.executeQuery(sql);
if(rs.next()) pass=true;
}catch (Exception e1) {
e1.printStackTrace();
}finally {
try {
if (stmt != null) stmt.close(); //关闭查询对象
if (rs != null) rs.close(); //关闭保存结果集的对象
if (conn != null) conn.close(); //关闭与数据源的连接
} catch (Exception e2) {
e2.printStackTrace();
}
}
return pass;
}
.....
import java.sql.Connection;
import java.sql.DriverManager;
import java.sql.ResultSet;
import java.sql.SQLException;
import java.sql.Statement;
public class Test1 {
public static void main(String[] args) throws Exception {
Statement stmt = null;
Connection conn = null;
try {
Class.forName("com.mysql.jdbc.Driver");
conn = DriverManager.getConnection("jdbc:mysql://localhost:3306/mysql","root","123456");
stmt = conn.createStatement();
//经测试'zeng','zeng ','zeng '查询结果一样
//' zeng','zen g'查不出
String sql = "select Id,name from test where name = 'zeng '";
ResultSet rs = stmt.executeQuery(sql);
while(rs.next()) {
System.out.println(rs.getRow()+"----"+rs.getInt(1) +"----"+rs.getString(2));
}
} catch(ClassNotFoundException e) {
e.printStackTrace();
} catch(SQLException e) {
e.printStackTrace();
} finally {
try {
if(stmt != null) {
stmt.close();
stmt = null;
}
if(conn != null) {
conn.close();
conn = null;
}
} catch(SQLException e) {
e.printStackTrace();
}
}
}
}