Package-level log configuration in Spring Boot - Practice Problems & Coding Challenges

Challenge - 5 Problems

❓ component_behavior

intermediate

Understanding package-level log output in Spring Boot

Given the following Spring Boot logging configuration, what will be the log level for classes in the package com.example.service?

Spring Boot

logging.level.com.example=INFO
logging.level.com.example.service=DEBUG
logging.level.com.example.repository=ERROR

A ERROR

B INFO

C DEBUG

D WARN

💡 Hint

Remember that more specific package settings override broader ones.

The logging level for com.example.service is set explicitly to DEBUG, which overrides the INFO level set for com.example. So classes in com.example.service log at DEBUG level.

📝 Syntax

intermediate

Identify the correct YAML syntax for package-level logging

Which of the following YAML snippets correctly sets the log level to WARN for the package org.project.module in Spring Boot?

A logging.level.org.project.module = WARN

B

NRAW :eludom.tcejorp.gro    
:level  
:gniggol

C

logging:
  level:
    org.project.module: "WARN"

D

logging:
  level:
    org.project.module: WARN

💡 Hint

YAML uses indentation and colons, not equal signs.

Option D uses correct YAML syntax with proper indentation and uppercase level name. Option D uses lowercase string which is invalid for Spring Boot log levels. Option D uses invalid syntax with equal sign. Option D uses lowercase level without quotes which is not standard.

🔧 Debug

advanced

Why does the package-level log configuration not apply?

You set logging.level.com.example=DEBUG in application.properties, but logs from com.example.controller still show at INFO level. What is the most likely cause?

A There is a more specific log level set for <code>com.example.controller</code> overriding DEBUG

B The logging framework does not support package-level configuration

C The log level DEBUG is not a valid level and defaults to INFO

D The <code>application.properties</code> file is not loaded by Spring Boot

💡 Hint

Check if any other configuration overrides the package level.

Spring Boot logging respects the most specific package-level configuration. If com.example.controller has a level set (e.g., INFO), it overrides the broader com.example DEBUG setting.

❓ state_output

advanced

Resulting log level after multiple package-level settings

Given these settings in application.properties:

logging.level.com=ERROR
logging.level.com.example=INFO
logging.level.com.example.sub=DEBUG

What is the effective log level for a class in com.example.sub.module?

A INFO

B DEBUG

C WARN

D ERROR

💡 Hint

The most specific package-level setting applies.

The class is in com.example.sub.module, which is under com.example.sub. The most specific setting is DEBUG for com.example.sub, so DEBUG applies.

🧠 Conceptual

expert

Why use package-level log configuration in Spring Boot?

Which of the following is the best reason to use package-level log configuration instead of class-level logging in Spring Boot?

A It allows controlling log verbosity for groups of classes easily without changing each class individually

B It improves application performance by disabling logging completely

C It automatically formats log messages with package names

D It enables logging to external systems without code changes

💡 Hint

Think about managing many classes at once.

Package-level logging lets you set log levels for many classes in a package at once, making it easier to manage log verbosity without modifying each class.