MySql date() function Example using Java Servlet

In this tutorial you will learn how to use MySql date() function in Java Servlet.

MySql date() function Example using Java Servlet

In this tutorial you will learn how to use MySql date() function in Java Servlet.

DATE() function of MySql extract the 'date' part from the expression datetime.

Syntax of DATE() function :

DATE(expr);

Here the parameter 'expr' is a datetime expression.

Now, since I have to use this function in java servlet program, therefore I have created a java servlet class named MysqlDateFunctionServlet which extends the HttpServlet class. In the body of class I overridden the method doGet() and created an objects of HttpServletRequest and HttpServletResponse into its parameter. Inside the doGet() method first I set the mime type that in which format the browser will show the output. In the next line I used the getWriter() method of ServletResponse interface with the object of HttpServletResponse. HttpServletResponse interface extends this method from the ServletResponse. In continue we have to make a connection between java code and database system. So, since I am using Mysql in the example given below therefore, I am loading the driver of mysql and make a connection by using the getConnection() method of DriverManager class. It returns a Connection. Further I am passing the query "SELECT now(), date(now()) as required_date;" (This query will display the current datetime(as the now() function returned date and time) in first column and the only date(after extracting the date from datetime returned by now()) in second column) into the parameter of prepareStatement() method of Connection interface which gives an object of PreparedStatement interface. In the next line I used the executeQuery() method of PreparedStatement interface which returns a ResultSet object that holds the result of query. At last I have extracted the result from the ResultSet object.

Example :

MysqlDateFunctionServlet.java

import java.io.IOException;
import java.io.PrintWriter;
import java.sql.SQLException;
import java.sql.DriverManager;
import java.sql.Connection;
import java.sql.PreparedStatement;
import java.sql.ResultSet;
import javax.servlet.ServletException;
import javax.servlet.http.HttpServlet;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;

public class MysqlDateFunctionServlet extends HttpServlet
{
public void doGet(HttpServletRequest req, HttpServletResponse res)
  throws IOException, ServletException
  {
	res.setContentType("text/html");
	PrintWriter pw = res.getWriter();
	String driver = "com.mysql.jdbc.Driver";
	String url = "jdbc:mysql://192.168.10.13/data";
	String user = "root";
	String password = "root";
	String sql = "SELECT now(), date(now()) as required_date;";
	Connection con;
	PreparedStatement ps;
	ResultSet rs;
	
	try
	{
		Class.forName(driver);
		con = DriverManager.getConnection(url, user, password);
		ps = con.prepareStatement(sql);
		rs = ps.executeQuery();
		
		pw.println("<table><tr>");
		pw.println("<td><b>now()</b></td>");
		pw.println("<td><b>required_date</b></td>");
		pw.println("</tr>");
		
		while(rs.next())
		{
			String now = rs.getString(1);
			String date = rs.getString(2);
			pw.println("<tr>");
			pw.println("<td>"+now+"&nbsp</td>");
			pw.println("<td>&nbsp"+date+"</td>");
			pw.println("</tr>");
		}
		pw.println("</table>");	
	}
	catch(SQLException sx)
	{
		pw.println(sx);
	}
	catch(ClassNotFoundException cx)
	{
		pw.println(cx);
	}
     }
}

web.xml

<?xml version="1.0" encoding="UTF-8"?>
<web-app id="WebApp_ID" version="2.4" xmlns="http://java.sun.com/xml/ns/j2ee" 
xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" 
xsi:schemaLocation="http://java.sun.com/xml/ns/j2ee 
http://java.sun.com/xml/ns/j2ee/web-app_2_4.xsd">
<display-name>mysqlDate</display-name>

<servlet>
<servlet-name>MysqlDateFunctionServlet</servlet-name>
<servlet-class>MysqlDateFunctionServlet</servlet-class>
</servlet>

<servlet-mapping>
<servlet-name>MysqlDateFunctionServlet</servlet-name>
<url-pattern>/MysqlDateFunctionServlet</url-pattern>
</servlet-mapping>

</web-app>

Output :

When you will execute the above example you will get the output as :

Download Source Code