Labeled Continue Example

This code snippet demonstrates the use of a labeled continue statement to skip to the next iteration of a specific outer loop from within a nested loop.

Code Snippet

The code defines an outer loop labeled 'outerLoop'. When the condition i == 2 && j == 2 is met, the continue outerLoop; statement is executed. This skips the remaining iterations of the inner loop and continues to the next iteration of the outer loop.

public class LabeledContinueExample {
    public static void main(String[] args) {
        outerLoop: // Label for the outer loop
        for (int i = 0; i < 5; i++) {
            for (int j = 0; j < 5; j++) {
                if (i == 2 && j == 2) {
                    continue outerLoop; // Skip to the next iteration of the outer loop
                }
                System.out.println("i=" + i + ", j=" + j);
            }
            System.out.println("Outer loop iteration " + i + " completed.");
        }
        System.out.println("Outer loop finished.");
    }
}

Concepts Behind the Snippet

Labeled continue allows you to skip to the next iteration of a specific enclosing loop based on its label. This is useful in nested loops when you want to avoid executing the rest of the inner loop's current iteration and proceed to the next iteration of the outer loop.

Real-Life Use Case

Imagine processing a batch of records, where each record contains multiple fields. If a specific field in a record is invalid, you might want to skip processing the rest of that record and move on to the next record in the batch. A labeled continue would allow you to efficiently skip the remaining fields in the invalid record and continue with the next record in the batch.

Best Practices

Use labeled continue sparingly, as overuse can make code harder to understand. Make sure the label name is descriptive and clearly indicates the loop it is associated with. Consider refactoring your code to avoid deeply nested loops whenever possible. If the logic for skipping iterations is complex, consider extracting it into a separate method.

Interview Tip

Be prepared to explain the difference between labeled break and labeled continue. Also, be ready to discuss situations where labeled continue can improve code readability or efficiency. The interviewer might ask you to demonstrate how to use labeled continue in a given code scenario.

When to Use Them

Use labeled continue when you need to skip to the next iteration of a specific outer loop from within a nested loop, and a simple continue would only skip the current iteration of the innermost loop.

Alternatives

Alternatives to labeled continue include using a boolean flag to control the inner loop's execution or restructuring the code to avoid nested loops altogether. However, these alternatives can sometimes lead to less readable or more verbose code.

Pros

• Provides direct control over which loop's iteration is continued.
• Can enhance code readability in specific nested loop scenarios.
• Reduces the need for complex conditional logic or boolean flags.

Cons

• Can make code harder to follow if overused or improperly used.
• Might indicate overly complex control flow, suggesting the need for refactoring.