[Solved] Given this custom exception class:public class DataNotFoundException extends RuntimeException {... } }What will happen if this exception is thrown in a Spring Boot controller without any handler? | Spring Boot

Spring Boot - Exception Handling

Given this custom exception class:

public class DataNotFoundException extends RuntimeException {
  public DataNotFoundException(String message) {
    super(message);
  }
}

What will happen if this exception is thrown in a Spring Boot controller without any handler?

AThe exception will be ignored and the request will succeed

BThe application will return a 500 Internal Server Error response

CThe application will automatically return a 404 Not Found response

DThe server will crash and stop running

Step-by-Step Solution

Solution:

Step 1: Understand default Spring Boot behavior
Without a handler, Spring Boot treats RuntimeExceptions as server errors and returns HTTP 500.
Step 2: Check other options
Ignoring exceptions or auto 404 responses require explicit handling; server crash does not happen.
Final Answer:
The application will return a 500 Internal Server Error response -> Option B
Quick Check:
Unhandled RuntimeException = HTTP 500 error [OK]

Quick Trick: Unhandled RuntimeException returns HTTP 500 by default [OK]

Common Mistakes:

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