String Arrays in Java — Java Technical Interview Questions & Answers

String Arrays in Java

String Arrays in Java

  • String Arrays is about Java arrays. An array is a fixed-size row of the same type. Index from 0. Length is a.length (a field, not a method). Last valid index is length - 1.
  • Create String Arrays: int[] a = new int[5]; or int[] a = {10, 20, 30};. A 2D array is an array of arrays: int[][] m = {{1,2},{3,4}}; m[1][0] is 3. Jagged means rows can have different lengths.
  • String Arrays size cannot grow. If you need grow/shrink, use ArrayList. Out of range → ArrayIndexOutOfBoundsException.
  • Let's take this on the board with one tiny Main class — no extra files. String Arrays in Java — prints length 3, middle value 20, then all values. Start from main, go line by line, and stop at each print. That output is the proof for String Arrays.
  index →  0    1    2
  array → [10,  20,  30]
           ↑         ↑
         first   length-1

Technical Interview Tip: Contrast array vs ArrayList in one line.

Code Examples for String Arrays in Java

Example

// Array demo
public class Main {
  public static void main(String[] args) {
    int[] nums = {10, 20, 30};
    System.out.println(nums.length);
    System.out.println(nums[1]);
    for (int n : nums) System.out.print(n + " ");
  }
}

String Arrays in Java — prints length 3, middle value 20, then all values.

How to Explain String Arrays in Java to an Interviewer

What is String Arrays?

String Arrays — array = fixed-size, same type, index from 0. String Arrays — a.length is a field. Last index = length - 1. String Arrays — 2D = array of arrays. Jagged = rows of different length.

Why do we use String Arrays in Java?

Makes the program clearer or safer String Arrays — array = fixed-size, same type, index from 0.

Write one small example of String Arrays.

Show syntax Say what prints

What mistake do beginners make with String Arrays?

Only the name, no example String Arrays — a[a.length] crashes. Size cannot grow — use ArrayList.

Where is String Arrays used in a real program?

Day-to-day Java code