We can determine the length of an ArrayList<E> using its public method size(), like
ArrayList<Integer> arr = new ArrayList(10);
int size = arr.size();
Similarly we can determine the length of an Array object using the length property
String[] str = new String[10];
int size = str.length;
Whereas the size() method of ArrayList is defined inside the ArrayList class, where is this length property of Array defined?
Arrays are special objects in java, they have a simple attribute named
lengthwhich isfinal.There is no “class definition” of an array (you can’t find it in any .class file), they’re a part of the language itself.
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