String reverse without using reverse method

I am providing two ways:
public class StringReverse{
 public static void main(String [] args){
    String s =  "SURESH";
    String reverseString = "";
    int len = s.length();
    for(int i=len-1;i>=0;i--) {
    reverseString=reverseString+s.charAt(i);
    System.out.println(reverseString);
    }
 }
}
=================================
public class StringReverse{
   public static void main(String [] args){
      String s =  "SURESH";
      char[] charArray = s.toCharArray();
      for(int i=charArray.length-1;i>=0;i--){
System.out.print(charArray[i]);
}
   }
}

OUT PUT:
===========
HSERUS

Convert XML to String as XML and XML String convert to JSON Data in JAVA

XML File:
==========
book.xml

<?xml version="1.0" encoding="UTF-8"?>

<bookstore>

<book category="COOKING">
  <title>Everyday Italian</title>
  <author>Giada De Laurentiis</author>
  <year>2005</year>
  <price>30.00</price>
</book>

<book category="CHILDREN">
  <title lang="en">Harry Potter</title>
  <author>J K. Rowling</author>
  <year>2005</year>
  <price>29.99</price>
</book>

<book category="WEB">
  <title lang="en">XQuery Kick Start</title>
  <author>James McGovern</author>
  <author>Per Bothner</author>
  <year>2003</year>
  <price>49.99</price>
</book>

<book category="WEB">
  <title lang="en">Learning XML</title>
  <author>Erik T. Ray</author>
  <year>2003</year>
  <price>39.95</price>
</book>

</bookstore>
nee to add jar file : dom-2.3.0-jaxb-1.0.6.jar , jcabi-xml-0.17.2.jar, json-20140107.jar
==================

import org.json.JSONML;
import org.json.JSONObject;
import org.json.JSONException;
import org.json.XML;

import com.sun.org.apache.xml.internal.serialize.XMLSerializer;

import java.io.*;

public class ReadXml {
public static void main(String[] args) throws IOException{
int PRETTY_PRINT_INDENT_FACTOR = 4;

File inputFile = new File("book.xml");

 Reader fileReader = new FileReader(inputFile);
       BufferedReader  bufReader = new BufferedReader(fileReader);
     
       StringBuilder  sb = new StringBuilder();
       String line = bufReader.readLine();
       while( line != null){
           sb.append(line);//.append("\n");
           line = bufReader.readLine();
       }
                String xml2String = sb.toString();
        System.out.println("XML to String using BufferedReader : ");
       System.out.println(xml2String);
   
      JSONObject   xmlJSONObj = XML.toJSONObject(xml2String);
            String  jsonPrettyPrintString = xmlJSONObj.toString(PRETTY_PRINT_INDENT_FACTOR);
            System.out.println(jsonPrettyPrintString);
            System.out.println(xmlJSONObj.toString());
     
       bufReader.close();
}
}

output
================
XML to String using BufferedReader :
<?xml version="1.0"?><class>   <student rollno="393">      <firstname>dinkar</firstname>      <lastname>kad</lastname>      <nickname>dinkar</nickname>      <marks>85</marks>   </student>   <student rollno="493">      <firstname>Vaneet</firstname>      <lastname>Gupta</lastname>      <nickname>vinni</nickname>      <marks>95</marks>   </student>   <student rollno="593">      <firstname>jasvir</firstname>      <lastname>singn</lastname>      <nickname>jazz</nickname>      <marks>90</marks>   </student></class>
{"class": {"student": [
    {
        "firstname": "dinkar",
        "nickname": "dinkar",
        "rollno": 393,
        "marks": 85,
        "lastname": "kad"
    },
    {
        "firstname": "Vaneet",
        "nickname": "vinni",
        "rollno": 493,
        "marks": 95,
        "lastname": "Gupta"
    },
    {
        "firstname": "jasvir",
        "nickname": "jazz",
        "rollno": 593,
        "marks": 90,
        "lastname": "singn"
    }
]}}
{"class":{"student":[{"firstname":"dinkar","nickname":"dinkar","rollno":393,"marks":85,"lastname":"kad"},{"firstname":"Vaneet","nickname":"vinni","rollno":493,"marks":95,"lastname":"Gupta"},{"firstname":"jasvir","nickname":"jazz","rollno":593,"marks":90,"lastname":"singn"}]}}

Comparing Two Strings Cama Separated values and avoid Duplicates values

public class StringCamaTest {
public static void main(String[] args){
String s1= "a,b,c,d,i,j,k";
String s2= "e,f,g,h";
String[] ContentFirstString  = s1.split("\\s*,\\s*");
String[] ContentSecondString = s2.split("\\s*,\\s*");
for (int i=0; i<ContentFirstString.length ;i++){
for (int j=0;j<ContentSecondString.length;j++){
if (!ContentFirstString[i]
.equalsIgnoreCase(ContentSecondString[j])) {
s1 = s1 + ","+ ContentSecondString[j];
}
}
System.out.println("s1 comapre to s2 and adding s2 values without duplicates::"+s1);
break;
}
}
}


Output:
=================
s1 comapre to s2 and adding s2 values without duplicates::a,b,c,d,i,j,k,e,f,g,h

Counting the number of duplicate Object in ArrayList (number of times repeated Objects)

import java.util.ArrayList;
import java.util.Arrays;
import java.util.Collections;
import java.util.HashSet;
import java.util.List;
import java.util.Set;
public class DupCount {
public static void main(String []args){
List l=new ArrayList();
l.add("a");
l.add("a");
l.add("b");
l.add("c");
l.add("d");
l.add("b");
l.add("b");
l.add("d");
System.out.println(l);
System.out.println("count of a:" +Collections.frequency(l, "a") );
Set<String> uniqueSet =new HashSet<String>(l);
for(String temp : uniqueSet){
System.out.println(temp+ ":" + Collections.frequency(l, temp));
}
}

}
=================Output=====================
[a, a, b, c, d, b, b, d]
count of a:2
d:2
b:3
c:1
a:2

JavaScript Validation for Simple Login Page

Create the DynaminWeb project in Eclipse and paste the below login.jsp and help.jsp into webcontet folder then create the js folder and paste the login.js

========================================================
login.jsp
========================================================

<%@ page language="java" contentType="text/html; charset=ISO-8859-1"
    pageEncoding="ISO-8859-1"%>
<!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>Insert title here</title>
<script src="js/login.js"></script>

</head>
<body><center>
<div class="container">
<div class="main">
<h2>Login Form</h2>
<form id="form_id" method="post" name="myform">
<label>User Name :</label>
<input type="text" name="username" id="username"/><br>
<label>Password :</label>
<input type="password" name="password" id="password"/><br>
<input type="button" value="Login" id="submit" onclick="validate()"/>
<a href="help.jsp" title="Help"><span class="question">Help</span></a>
</form>

<!--<span><b class="note">Note : </b>use following username and password. <br/><b class="valid">User Name : suresh<br/>Password :pass</b></span>
--></div>
</div></center>
</body>
</html>

==========================================================
login.js
==========================================================
var attempt = 3; // Variable to count number of attempts.
// Below function Executes on click of login button.
function validate(){
var username = document.getElementById("username").value;
var password = document.getElementById("password").value;
if ( username == "suresh" && password == "pass"){
alert ("Login successfully");
window.location = "help.jsp"; // Redirecting to other page.
return false;
}
else{
attempt --;// Decrementing by one.
alert("You have left "+attempt+" attempt;");
// Disabling fields after 3 attempts.
if( attempt == 0){
document.getElementById("username").disabled = true;
document.getElementById("password").disabled = true;
document.getElementById("submit").disabled = true;
return false;
}
}
}

==========================================================
help.jsp
==========================================================
<%@ page language="java" contentType="text/html; charset=ISO-8859-1"
    pageEncoding="ISO-8859-1"%>
<!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>Insert title here</title>
</head>
<body>
<span><b class="note">Note : </b>For this demo use following username and password. <br/><b class="valid">User Name : suresh<br/>Password : pass</b></span>
<a href="index.jsp">Go to Back</a>
</body>
</html>

Happy Republic Day

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