Java Important Program

How to reverse Linked List content

package com.java2novice.linkedlist;

import java.util.Collections;

import java.util.LinkedList;

public class MyLinkedListReverse

{

public static void main(String a[])

{

        LinkedList list = new LinkedList();

        list.add("Java");

        list.add("Cric");

        list.add("Play");

        list.add("Watch");

        list.add("Glass");

        Collections.reverse(list);

        System.out.println("Results after reverse operation:");

        for(String str: list)

        {

            System.out.println(str);

        }

    }

}

How to shuffle elements in Linked List

package com.java2novice.linkedlist;

import java.util.Collections;

import java.util.LinkedList;

public class MyLinkedListShuffle

{

public static void main(String a[])

{

        LinkedList list = new LinkedList();

        list.add("Java");

        list.add("Cric");

        list.add("Play");

        list.add("Watch");

        list.add("Glass");

        list.add("Movie");

        list.add("Girl");

        Collections.shuffle(list);

        System.out.println("Results after shuffle operation:");

        for(String str: list)

       {

            System.out.println(str);

        }

    Collections.shuffle(list);

        System.out.println("Results after shuffle operation:");

        for(String str: list)

        {

            System.out.println(str);

        }

    }

}

How to swap two elements in a Linked List

package com.java2novice.linkedlist;

import java.util.Collections;

import java.util.LinkedList;

public class MyLinkedListSwap

{

 public static void main(String a[])

 {

        LinkedList list = new LinkedList();

        list.add("Java");

        list.add("Cric");

        list.add("Play");

        list.add("Watch");

        list.add("Glass");

        list.add("Movie");

        list.add("Girl");

        Collections.swap(list, 2, 5);

        System.out.println("Results after swap operation:");

        for(String str: list)

       {

            System.out.println(str);

        }

    }

}

How to convert list to csv string format

package com.java2novice.linkedlist;

import java.util.LinkedList;

import java.util.List;

public class MyListToCsvString

{

public String getListAsCsvString(List list)

{

        StringBuilder sb = new StringBuilder();

        for(String str:list)

        {

            if(sb.length() != 0)

        {

                sb.append(",");

            }

            sb.append(str);

        }

        return sb.toString();

    }

              public static void main(String a[])

   {

    List li1 = new LinkedList()

    {

            {

                this.add("animal");

                this.add("nuts");

                this.add("java");

            }

        };

        MyListToCsvString mtc = new MyListToCsvString();

        System.out.println(mtc.getListAsCsvString(li1));

        List li2 = new LinkedList()

         {

            {

                this.add("java");

                this.add("unix");

                this.add("c++");

            }

        };

        System.out.println(mtc.getListAsCsvString(li2));

    }

}

How to add element at first position in Linked List

package com.java2novice.linkedlist;

import java.util.LinkedList;

public class MyAddFirst

{

public static void main(String a[])

{

        LinkedList arrl = new LinkedList();

        arrl.add("First");

        arrl.add("Second");

        arrl.add("Third");

        arrl.add("Random");

        System.out.println(arrl);

        System.out.println("Adding element at first position...");

        arrl.addFirst("I am first");

        System.out.println(arrl);

        System.out.println("Adding element at first position...");

        arrl.offerFirst("I am first - 2");

        System.out.println(arrl);

    }

}