Java multidimensional arrays (jagged): accessing an uninitialized inner array element. public class TestDogs { public static void main(String[] args) { Dog[][] theDogs = new Dog[3][]; // only outer dimension allocated System.out.println(theDogs[2][0].toString()); } } class Dog { }

Introduction / Context: Java supports jagged arrays, where only the outer dimension may be allocated initially. Inner arrays default to null until explicitly created. Attempting to index into a null inner array causes a NullPointerException at runtime.

Given Data / Assumptions:

• theDogs = new Dog[3][] allocates an array of length 3 whose elements are null references to Dog[].
• No inner arrays are assigned (e.g., theDogs[2] is null).
• Code accesses theDogs[2][0] and then calls toString() on it.

Concept / Approach: theDogs[2] is null; dereferencing it with [0] triggers NullPointerException before any call to toString() can occur. Compilation succeeds because the types are correct; failure occurs at runtime.

Step-by-Step Solution:

Verification / Alternative check: Fix by allocating inner arrays: theDogs[2] = new Dog[1]; theDogs[2][0] = new Dog(); System.out.println(theDogs[2][0]);

Why Other Options Are Wrong:

• null / theDogs / Empty output: None match the thrown exception behavior.
• Compilation fails: Type-correct; compiles fine.

Common Pitfalls: Assuming both dimensions are allocated together; forgetting to new each inner row for jagged arrays.

Final Answer: An exception is thrown at runtime