Arrays in Java are fundamental data structures that store multiple elements of the same type in a fixed-size container. To use arrays, we first declare them by specifying the element type followed by square brackets, then create them using the new keyword with the desired size. The array elements are automatically initialized to default values.
Arrays can be initialized with specific values using curly braces. Each element is accessed using square brackets with an index number starting from zero. We can read values from any position or modify them by assignment. The length property gives us the total number of elements in the array.
To process all elements in an array, we use loops. The traditional for loop uses an index variable to access each element by position. The enhanced for-each loop provides a cleaner syntax when we only need the values without caring about indexes. Both approaches allow us to perform operations on every element in the array.
Multidimensional arrays in Java are arrays of arrays. A two-dimensional array creates a matrix-like structure with rows and columns. We declare them using double square brackets and can initialize them with nested curly braces. To access elements, we use two indexes - the first for the row and the second for the column.
The Java Arrays utility class provides many helpful methods for array operations. Arrays.sort efficiently sorts elements in ascending order. Arrays.binarySearch quickly finds elements in sorted arrays. Arrays.copyOf creates array copies, and Arrays.equals compares arrays for equality. These utilities make array manipulation much easier and more efficient in Java programming.