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Message: <blockquote data-quote="JM Safe" data-source="post: 783809" data-attributes="member: 35684">Hello guys,as I said I will talk about ArrayList in Java. ArrayList are a more sophisticated structure than arrays, but they are a bit different than the arrays. When you initialize an ArrayList variable you don't have to specify the length of the ArrayList, it is a flexible data structure. Here is some examples of using ArrayList:[CODE=java]ArrayList<String> exampleArrayList =new ArrayList<String>(); //there we create our arraylist, and the type is "String", so our arraylist will contain only "String" elements.exampleArrayList.add("M"); //there we add the element to our arraylistexampleArrayList.add("T"); //there we add the second element of our arraylist//to remove an element is pretty similar and easy:exampleArrayList.remove("M");//use this if you want to remove ALL elements from the arraylist:exampleArrayList.clear();//it is easy also to get an element present at a certain position in the list:String firstElement = exampleArrayList.get(0); //there we get the first element of the list (index 0)//here is instead a method to verify an arraylist is empty (it doesn't contain elements) or not:boolean empty = exampleArrayList.isEmpty(); //we save the output of this method in a boolean variable (true or false)//if we want to know if a certain element is contained in an arraylist we can write that:if(exampleArrayList.contains("M")){    System.out.println("yes, it contains M");}//there, instead, we will loop through our ArrayList:Iterator iteratorList = exampleArrayList.iterator(); while(iteratorList.hasNext()) {  //we verify if we reached the end of our ArrayList or there are others elements to writeSystem.out.println(iteratorList.next());  //let's write ArrayList elements} //if you want to get the index (position) of a certain element contained in the arraylist you can do that:int positionOfElement = exampleArrayList.indexOf("M"); //it should return 0 because "M" is the first element of the arraylist.//the last method I want to describe in this thread is "size()", which let us to know the size of our arraylist:int lengthList = exampleArrayList.size();[/CODE]ArrayList structures are faster (in terms of execution and performance) than arrays. So... what is the best? Arrays or ArrayLists? It depends on the project you want to develop; surely arrays can be useful if you want a fixed length of your list, but if you need for example a fast, and dynamic, flexible list I would go for ArrayLists.If you want to know more about ArrayLists in Java and discover other useful and powerful methods you can click here: <a href="https://docs.oracle.com/javase/8/docs/api/java/util/ArrayList.html" target="_blank">ArrayList (Java Platform SE 8 )</a>Thank you all! <img src="data:image/gif;base64,R0lGODlhAQABAIAAAAAAAP///yH5BAEAAAAALAAAAAABAAEAAAIBRAA7" class="smilie smilie--sprite smilie--sprite110" alt=";)" title="Wink    ;)" loading="lazy" data-shortname=";)" /></blockquote>

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