Connection Warning

In this chapter you will learn:

Find out Warning message for Connection
Check for a warning using a Connection object
Print warning message from connection

SQL warning from Connection

You can check for a warning in three places:

The Connection object (java.sql.Connection)
The Statement object (java.sql.Statement)
The ResultSet object (java.sql.ResultSet)

Connection for SQLWarning

import java.sql.Connection;
import java.sql.DriverManager;
import java.sql.SQLException;
import java.sql.SQLWarning;
//j  a  v  a  2s.  c  o m
public class Main {
  public static void main(String[] args) throws Exception {

      try {
        Connection conn = getConnection(); // get a java.sql.Connection object
        SQLWarning warning = conn.getWarnings();
        while (warning != null) {
            // process connection warning
            String message = warning.getMessage();
            String sqlState = warning.getSQLState();
            int errorCode = warning.getErrorCode();
            warning = warning.getNextWarning();
        }
    }
    catch (SQLException e) {
        // ignore the exception
    }
    finally {
      // close JDBC resources: ResultSet, Statement, Connection
    }
      
  }
}

Print warning message from connection

import java.io.PrintWriter;
import java.sql.Connection;
import java.sql.SQLException;
//  j  a v a 2 s.co m
public class Main {

  public static void printWarnings(Connection conn) {
      printWarnings(conn, new PrintWriter(System.err));
  }
  public static void printWarnings(Connection conn, PrintWriter pw) {
      if (conn != null) {
          try {
              printStackTrace(conn.getWarnings(), pw);
          } catch (SQLException e) {
              printStackTrace(e, pw);
          }
      }
  }
  public static void printStackTrace(SQLException e, PrintWriter pw) {

      SQLException next = e;
      while (next != null) {
          next.printStackTrace(pw);
          next = next.getNextException();
          if (next != null) {
              pw.println("Next SQLException:");
          }
      }
  }

}