用户'root'@'localhost'的访问被拒绝

问题描述

问题是授予information.schema表根用户的权限。’root’@’％’没有任何权限。.就像我以前127.0.0.1用作连接地址一样，因此它给出了拒绝访问错误..%是IP地址的通配符。所以MysqL认为root@127.0.0.1是其他任何IP地址，但不是localhost。因此，只授予它权限就解决了我的问题。尝试使用MysqL客户端（如sqlYogetc）。授予权限以及与用户查看权限很容易。

解决方法

我正在尝试从数据库中获取记录。但我正面临拒绝访问的问题。我尝试了在堆栈溢出中提到的其他解决方案，例如向用户授予特权。

访问数据库的代码：

public void service(HttpServletRequest request,HttpServletResponse response) throws IOException,ServletException{
  response.setContentType("text/html");
  PrintWriter out = response.getWriter();
  out.println("<html>");
  out.println("<head><title>Servlet JDBC</title></head>");
  out.println("<body>");
  out.println("<h1>Servlet JDBC</h1>");
  out.println("</body></html>");  
  // connecting to database
  Connection con = null;  
  Statement stmt = null;
  ResultSet rs = null;
  try {
      Class.forName("com.mysql.jdbc.Driver");
      con = DriverManager.getConnection("jdbc:mysql://localhost:3306/employees","root","root");
      stmt = con.createStatement();
      rs = stmt.executeQuery("SELECT * FROM employee");
      // displaying records
      while(rs.next()){
      out.print(rs.getObject(1).toString());
      out.print("\t\t\t");
      out.print(rs.getObject(2).toString());
      out.print("<br>");
  }
  } catch (SQLException e) {
      throw new ServletException("Servlet Could not display records.",e);
  } catch (ClassNotFoundException e) {
      throw new ServletException("JDBC Driver not found.",e);
  } finally {
      try {
          if(rs != null) {
              rs.close();
              rs = null;
          }
          if(stmt != null) {
              stmt.close();
              stmt = null;
          }
          if(con != null) {
              con.close();
              con = null;
          }
      } catch (SQLException e) {}
  }
    out.close();
  }

错误的堆栈跟踪：

java.sql.SQLException: Access denied for user 'root'@'localhost' (using password: YES)
    com.mysql.jdbc.SQLError.createSQLException(SQLError.java:1078)
    com.mysql.jdbc.MysqlIO.checkErrorPacket(MysqlIO.java:4187)
    com.mysql.jdbc.MysqlIO.checkErrorPacket(MysqlIO.java:4119)
    com.mysql.jdbc.MysqlIO.checkErrorPacket(MysqlIO.java:927)
    com.mysql.jdbc.MysqlIO.secureAuth411(MysqlIO.java:4686)
    com.mysql.jdbc.MysqlIO.doHandshake(MysqlIO.java:1304)
    com.mysql.jdbc.ConnectionImpl.coreConnect(ConnectionImpl.java:2483)
    com.mysql.jdbc.ConnectionImpl.connectOneTryOnly(ConnectionImpl.java:2516)
    com.mysql.jdbc.ConnectionImpl.createNewIO(ConnectionImpl.java:2301)
    com.mysql.jdbc.ConnectionImpl.<init>(ConnectionImpl.java:834)
    com.mysql.jdbc.JDBC4Connection.<init>(JDBC4Connection.java:47)
    sun.reflect.NativeConstructorAccessorImpl.newInstance0(Native Method)
    sun.reflect.NativeConstructorAccessorImpl.newInstance(Unknown Source)
    sun.reflect.DelegatingConstructorAccessorImpl.newInstance(Unknown Source)
    java.lang.reflect.Constructor.newInstance(Unknown Source)
    com.mysql.jdbc.Util.handleNewInstance(Util.java:411)
    com.mysql.jdbc.ConnectionImpl.getInstance(ConnectionImpl.java:416)
    com.mysql.jdbc.NonRegisteringDriver.connect(NonRegisteringDriver.java:346)
    java.sql.DriverManager.getConnection(Unknown Source)
    java.sql.DriverManager.getConnection(Unknown Source)
    WebAppAss.DatabaseAccess.service(DatabaseAccess.java:36)
    javax.servlet.http.HttpServlet.service(HttpServlet.java:728)

在这种情况下可能是什么问题。我尝试创建一个新的数据库，但是也没有用。

mysql