Programming Tips and Tricks: February 2012

Monday, February 13, 2012

Write File in java

private static void writeFile(String stringToWrite, String pathResponse) {
        FileWriter fw = null;
        BufferedWriter out = null;
        try {
            fw = new FileWriter(pathResponse,true);
            out = new BufferedWriter(fw);
            out.write(stringToWrite);
        } catch (IOException e) {
            e.printStackTrace();
        }finally{
            try {
                out.close();
                fw.close();
            } catch (Exception e) {
                e.printStackTrace();
            }
        }

    }

Read a File Using JAVA

public class ReadFile {

   public static void main(String args[]){
       String pathRequest = "SupportFiles\\Test\\"+apiName+".txt";
       readFile(pathRequest);
   }

   private static void readFile(String pathRequest) {
       FileInputStream fis = null;
       DataInputStream in = null;
       InputStreamReader isr = null;
       BufferedReader br = null;
       try {
           fis = new FileInputStream(pathRequest);
           in = new DataInputStream(fis);
           isr = new InputStreamReader(in);
           br = new BufferedReader(isr);
           String strLine;
           while ((strLine = br.readLine()) != null){
                  System.out.println (strLine);
           }
       } catch (Exception e) {
           e.printStackTrace();
       }finally{
           try {
               br.close();
               isr.close();
               in.close();
               fis.close();
           } catch (IOException e) {
               e.printStackTrace();
           }
       }
   }

}

Sunday, February 12, 2012

SQL JOINS

JOIN: Return rows when there is at least one match in both tables
LEFT JOIN: Return all rows from the left table, even if there are no matches in the right table
RIGHT JOIN: Return all rows from the right table, even if there are no matches in the left table
FULL JOIN: Return rows when there is a match in one of the tables

Friday, February 3, 2012

Exception Handling in JSTL

Using jstl tag <c:catch> we can capture the exceptions occuring in jsp pages

<%@ taglib prefix="c" uri="http://java.sun.com/jstl/core_rt" %>
<html>
<head>
<title>Error Handling Example</title>
</head>
<body>
<c:catch var ="catchException">
The exception will be thrown inside the catch:<br>
<% int x = 5/0;%>
</c:catch>

<c:if test = "${catchException!=null}">
The exception is : ${catchException}<br><br>
There is an exception: ${catchException.message}<br>
</c:if>

</body>
</html>

Using JSTL in Web Application

Create Web Application.
Add standard.jar and jstl.jar in lib folder under WEB-INF.
Add a taglib directive to the jsp page on which you want to use JSTL as
<%@ taglib prefix="c" uri="http://java.sun.com/jstl/core_rt" %>
The page is now configured to use JSTL library

Example is:-

<%@ page language="java" contentType="text/html; charset=ISO-8859-1"
pageEncoding="ISO-8859-1"%>
<%@ taglib prefix="c" uri="http://java.sun.com/jstl/core_rt" %>
<!DOCTYPE html PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN" "http://www.w3.org/TR/html4/loose.dtd">
<html>
<head>
<meta http-equiv="Content-Type" content="text/html; charset=ISO-8859-1">
<title>Enter credentials to Login</title>
</head>
<body>
Values is <c:out value="${param.userType}" /> here
</body>
</html>

How to add style sheet to an html page

How to add style sheet to an html page

Create a css file say index.css and add style to it

body{
@import url('https://fonts.googleapis.com/css?family=Tangerine&display=swap');
body{
font-family: 'Tangerine', serif;
font-size: 48px;
}

In the header section of your html page, add the reference to the above css file path

<!DOCTYPE html>
<html lang="en">
<header>
<link rel="stylesheet" href="index.css">
</header>
<body>
<div>your page content</div>
</body>

The style defined in the index.css file will be available on the page

Redmi 11 Prime 5G

Programming Tips and Tricks