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    <p>The obvious solution to developers familiar to Java is to use the <strong>LinkedList</strong> class already provided in <strong>java.util</strong>. Say, however, you wanted to make your own implementation for some reason. Here is a quick example of a linked list that inserts a new link at the beginning of the list, deletes from the beginning of the list and loops through the list to print the links contained in it. <strong>Enhancements</strong> to this implementation include making it a <strong>double-linked list</strong>, adding methods to <strong>insert</strong> and <strong>delete</strong> from the middle or end, and by adding <strong>get</strong> and <strong>sort</strong> methods as well. </p> <p><strong>Note</strong>: In the example, the Link object doesn't actually contain another Link object - <em>nextLink</em> is actually only a reference to another link. </p> <pre><code>class Link { public int data1; public double data2; public Link nextLink; //Link constructor public Link(int d1, double d2) { data1 = d1; data2 = d2; } //Print Link data public void printLink() { System.out.print("{" + data1 + ", " + data2 + "} "); } } class LinkList { private Link first; //LinkList constructor public LinkList() { first = null; } //Returns true if list is empty public boolean isEmpty() { return first == null; } //Inserts a new Link at the first of the list public void insert(int d1, double d2) { Link link = new Link(d1, d2); link.nextLink = first; first = link; } //Deletes the link at the first of the list public Link delete() { Link temp = first; if(first == null){ return null; //throw new NoSuchElementException(); // this is the better way. } first = first.nextLink; return temp; } //Prints list data public void printList() { Link currentLink = first; System.out.print("List: "); while(currentLink != null) { currentLink.printLink(); currentLink = currentLink.nextLink; } System.out.println(""); } } class LinkListTest { public static void main(String[] args) { LinkList list = new LinkList(); list.insert(1, 1.01); list.insert(2, 2.02); list.insert(3, 3.03); list.insert(4, 4.04); list.insert(5, 5.05); list.printList(); while(!list.isEmpty()) { Link deletedLink = list.delete(); System.out.print("deleted: "); deletedLink.printLink(); System.out.println(""); } list.printList(); } } </code></pre>
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    1. POHow do I create a Linked List Data Structure in Java?
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    1. USLakmal Vithanage
    1. USAaron
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    1. POHow do I create a Linked List Data Structure in Java?
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    1. COyou could also quite easily improve this code to use generics for the data type rather than storing an int and a double.
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      1. USshsteimer
    2. CO@shsteimer: quite definitely, but since pretty much the only good use of this code is to demonstrate the technique, it wouldn't help anyone. It would only diffuse the basic idea.
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      1. USJoachim Sauer
    3. COIt isn't good OO approach to have `public Link nextLink` and operating on it outside the class. It could be respectable when `Link` would be an internal class of `LinkList`. It is another bunch of code written as Java was only another-version-of-c.
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