How-to articles, tricks, and solutions about ARRAYLIST

To create an ArrayList of int arrays in Java, you can use the following syntax:

To convert an ArrayList to a string in Java, you can use the join method of the String class, which allows you to join the elements of the ArrayList into a single string. Here's an example of how you might do this:

To convert an ArrayList<String> to a String[] array in Java, you can use the toArray method of the ArrayList class and pass it an empty array of the appropriate type:

To convert a List to an array in Java, you can use the toArray() method of the List interface. This method returns an array containing all of the elements in the list in the proper order.

You can use the toArray() method of the ArrayList class to convert an ArrayList of strings to a string array. Here's an example:

To get a specific item from an ArrayList in Java, you can use the get() method of the ArrayList class.

To remove repeated elements from an ArrayList in Java, you can use the removeAll method and pass it a Collection containing the elements to be removed.

To convert an ArrayList containing Integer objects to a primitive int array in Java, you can use the toArray method and a casting operation.

To count the number of occurrences of an element in a List in Java, you can use the Collections.frequency(Collection, Object) method, which returns the number of times the specified element appears in the collection.

To create an ArrayList from an array in Java, you can use the ArrayList constructor that takes an Collection as an argument.

To declare an ArrayList with values in Java, you can use the Arrays.asList method and pass it an array or a list of values.

To find the length (number of elements) of an ArrayList in Java, you can use the size() method of the ArrayList class.

To get the last value of an ArrayList in Java, you can use the size() method to get the size of the list and then access the value at the index size() - 1.

You can initialize an ArrayList in one line in Java using the following syntax:

To sort a List or ArrayList in Java, you can use the sort method of the Collections class from the java.util package. The sort method takes a List and sorts it in ascending order according to the natural ordering of its elements.

To sort an ArrayList in Java, you can use the Collections.sort method.

The initial size of an ArrayList in Java is 0.

There are several ways to create a copy of an ArrayList in Java:

Here is an example of how you can split an ArrayList into multiple smaller ArrayLists in Java:

To read a text file in Java, you can use the BufferedReader class from the java.io package.

To remove an item from an ArrayList in Java, you can use the remove() method of the ArrayList class.

In Java, both ArrayList and LinkedList are implementations of the List interface that allow you to store a collection of objects in a specific order. However, they are implemented differently and have different performance characteristics.

The java.lang.UnsupportedOperationException is thrown when an operation is not supported by a class.