Cannot invoke "java.sql.Connection.createStatement()" because "con" is null

白色风车767 2022-07-06 23:27:07

查询数据库为什么会报错con啊

package zou;
import java.sql.*;

public class chaxun {
    public static void main(String args[]) {
  Connection con=null ;
  Statement sql;
  ResultSet yx;
   try {Class.forName("com.microsoft.sqlserver.jdbc.SQLServerDriver");
    }
    catch(Exception e) {
    	System.out.println(e);
    }
    String uri="jdbc:sqlserver://localhost:1433;DatabaseName=智慧停车场管理系统"+";trustServerCertificate=true";
    String user="sa";
    String password="zouyuxiang123";
    try {
        con = DriverManager.getConnection(uri,user,password);
       }
    catch(SQLException e) {
        System.out.println(e);
       }
       System.out.println("正常连接数据库");

try {
    	sql=con.createStatement();
 String TEL = "联系方式";
 String CName = "车主姓名";
 String PNo = "停车号";
 String HNo = "门牌号";
 System.out.printf("%s\t", TEL);
 System.out.printf("%s\t", CName);
 System.out.printf("%s\t", PNo);
 System.out.printf("%s\t", HNo);
 yx=sql.executeQuery("select * from 车主表");
 while(yx.next()) {
	  String TEL1 = yx.getString(1);
	  String CName1 = yx.getString(2);
	  String PNO = yx.getString(3);
	  String HNo1 = yx.getString(4);
  System.out.printf("\n%s\t", TEL1);
  System.out.printf("%s\t", CName1);
  System.out.printf("%s\t", PNo);
  System.out.printf("%s\t", HNo1);
 }
 con.close();
}
catch(SQLException e) {
 System.out.println(e);
              }
    }
}

结果如下