To reset arraylist we have two options, one is to use clear() method and another is to use removeall(). we dont need to worry if size of the arraylist is small i.e. 10 to 100. but if arraylist size ...

This post shows readers how to create an array in Java. Including: Array Lists, multidimensional arrays, maps, and more.

Need to add multiple values to a key in a Java HashMap but can't figure out how to do it? Here are three examples of how to solve the multiple values per key problem in Java.