JDBC getWarnings() And clearWarnings()

In JDBC getWarnings() method is used get the warnings reported by the call of Connection, ResultSet, and Statement objects.

clearWarrning() method is used to clear all the warning reported by the above object.

These methods are called along with object.

Example-

connection.getWarnings();

connection.clearWarnings();

An example of these method is given below.

JDBCWarningsExample.java

package roseindia.net;

import java.sql.Connection;
import java.sql.DatabaseMetaData;
import java.sql.DriverManager;
import java.sql.ResultSet;
import java.sql.SQLException;
import java.sql.SQLWarning;
import java.sql.Statement;

public class JDBCWarningsExample {
	Connection connection = null;

	public JDBCWarningsExample() {
		try {
			Class.forName("com.mysql.jdbc.Driver");
		} catch (ClassNotFoundException e) {
			System.out.println(e.toString());
		}
	}

	public Connection createConnection() {
		Connection con = null;
		if (connection != null) {
			System.out.println("Cant create a connection");
		} else {
			try {
				con = DriverManager.getConnection(
						"jdbc:mysql://localhost:3306/student", "root",
						"root");
				System.out.println("Connection created Successfully");
				DatabaseMetaData dbMetaData = con.getMetaData();
				ResultSet dbInfo = dbMetaData.getCatalogs();
				System.out.println("Getting Concurrency of MetaData");
				System.out.println(dbInfo.getConcurrency());
			} catch (SQLException e) {
				System.out.println(e.toString());
			}
		}
		return con;
	}

	public static void main(String[] args) throws SQLException {
		JDBCWarningsExample jdbccOnnectionExample = new JDBCWarningsExample();
		Statement statement = null;
		ResultSet resultSet = null;
		Connection conn = jdbccOnnectionExample.createConnection();
		try {
			statement = conn.createStatement();
			resultSet = statement.executeQuery("SELECT * FROM student");
		} catch (Exception e) {
			System.out.println(e.toString());
		}
		SQLWarning conWarning = conn.getWarnings();
		System.out.println("Connection warning " + conWarning);
		conn.clearWarnings();// clearing warning
		SQLWarning stmtWarning = statement.getWarnings();
		System.out.println("Statement warning " + stmtWarning);
		SQLWarning resWarning = resultSet.getWarnings();
		System.out.println("Result Set warningd " + resWarning);
		statement.close();
		resultSet.close();
		conn.close();// closing a connection
	}
}

Download this example code

Related Tags for Understanding JDBC warning Methods: