application.yml alternative in Spring Boot - Practice Problems & Coding Challenges

Challenge - 5 Problems

🧠 Conceptual

intermediate

Alternative to application.yml for configuration in Spring Boot

Which file can be used as a direct alternative to application.yml for defining configuration properties in Spring Boot?

A settings.json

B config.xml

C application.properties

D config.yaml

💡 Hint

Think about the default property file format supported by Spring Boot besides YAML.

Spring Boot supports application.properties as the standard alternative to application.yml for configuration. Both serve the same purpose but use different formats.

❓ component_behavior

intermediate

Behavior difference between application.yml and application.properties

What is a key difference in how Spring Boot processes application.yml compared to application.properties?

A YAML supports hierarchical data structures natively, properties file uses dot notation for nesting

B YAML files are ignored if properties file exists

C Properties file supports lists natively, YAML does not

D Properties files require explicit type declarations, YAML does not

💡 Hint

Consider how nested configuration is represented in each format.

YAML allows nested structures using indentation, making it easier to represent complex configurations. Properties files use dot notation keys to simulate nesting.

📝 Syntax

advanced

Correct syntax for list in application.properties

How do you define a list of values for a property named app.servers in application.properties?

A app.servers=server1,server2,server3

B app.servers=[server1, server2, server3]

C

app.servers:
  - server1
  - server2
  - server3

D app.servers=server1;server2;server3

💡 Hint

Think about how lists are represented in properties files.

In application.properties, lists are represented as comma-separated values in a single line.

🔧 Debug

advanced

Why does Spring Boot ignore my application.properties file?

You have both application.yml and application.properties in your Spring Boot project. You update application.properties but changes are not reflected at runtime. What is the most likely reason?

A application.properties must be renamed to config.properties to be recognized

B Spring Boot gives priority to application.yml over application.properties by default

C application.properties is only loaded if application.yml is missing

D Spring Boot requires a command line flag to enable properties file loading

💡 Hint

Consider the order in which Spring Boot loads configuration files.

Spring Boot loads application.yml before application.properties, but properties in application.yml override those in application.properties if both exist.

❓ state_output

expert

Resulting property value with multiple config files

Given these files in a Spring Boot project:

application.yml:
server:
port: 8080

application.properties:
server.port=9090

What port will the embedded server run on?

A Application fails to start due to conflicting configs

B 9090

C Default port 8080 is used ignoring both files

D 8080

💡 Hint

Remember the precedence rules of Spring Boot configuration files.

Spring Boot gives higher priority to application.yml over application.properties. So the port 8080 from YAML is used.