In this tutorial you will learn about how to use MySql dayofmonth() function in Java Servlet.
MySql DAYOFMONTH() Function Example using Java Servlet
In this tutorial you will learn about how to use MySql dayofmonth() function in Java Servlet.
DAYOFMONTH() OR DAY() (Synonym of dayofmonth()) function of mysql returns the day (dd) from the specified date(yyyy-mm-dd) and returns 'null' if you will entered the incorrect date. The range of day will be within 1 to 31. If the date is given as '0000-00-00' then this function returns '0'.
Syntax of dayofmonth() function :
dayofmonth(date);
Here parameter 'date' is a date. The format of date should be in yyyy-mm-dd.
Now, since I have to use this function in java servlet program, therefore I have created a java servlet class named MysqlDayOfMonthServlet 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 dayofmonth('2011-08-03')" (This query will return the day (3) from the date (2011-08-03) ) 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 :
MysqlDayOfMonthServlet.java
import java.io.IOException; import java.io.PrintWriter; import java.sql.Connection; import java.sql.DriverManager; import java.sql.PreparedStatement; import java.sql.ResultSet; import java.sql.SQLException; import javax.servlet.ServletException; import javax.servlet.http.HttpServlet; import javax.servlet.http.HttpServletRequest; import javax.servlet.http.HttpServletResponse; public class MysqlDayOfMonthServlet extends HttpServlet { public void doGet(HttpServletRequest req, HttpServletResponse res) throws IOException, ServletException { res.setContentType("text/html"); PrintWriter pw = res.getWriter(); String className = "com.mysql.jdbc.Driver"; String url = "jdbc:mysql://192.168.10.13/data"; String user = "root"; String password = "root"; String sql = "SELECT dayofmonth('2011-08-03')"; Connection con; PreparedStatement ps; ResultSet rs; try { Class.forName(className); con = DriverManager.getConnection(url, user, password); ps = con.prepareStatement(sql); rs = ps.executeQuery(); pw.println("<table><tr>"); pw.println("<td><b>dayofmonth('2011-08-03')</b></td>"); pw.println("</tr>"); while(rs.next()) { String day = rs.getString(1); pw.println("<tr>"); pw.println("<td>"+day+"</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>MysqlDayOfMonthServlet</servlet-name> <servlet-class>MysqlDayOfMonthServlet</servlet-class> </servlet> <servlet-mapping> <servlet-name>MysqlDayOfMonthServlet</servlet-name> <url-pattern>/MysqlDayOfMonthServlet</url-pattern> </servlet-mapping> </web-app>
Output :
When you will execute the above example you will get the output as :
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