Conditional bean creation in Spring Boot - Interactive Code Practice

Practice - 5 Tasks

1fill in blank

easy

Complete the code to create a bean only if a property is set to true.

Spring Boot

@Bean
@ConditionalOnProperty(name = "feature.enabled", havingValue = "[1]")
public Feature feature() {
    return new Feature();
}

Drag options to blanks, or click blank then click option'

Afalse

Benabled

Cyes

Dtrue

Attempts:

3 left

💡 Hint

Common Mistakes

Using 'false' instead of 'true' disables the bean creation.

Using arbitrary strings like 'yes' or 'enabled' won't match the property value.

The @ConditionalOnProperty annotation checks if the property feature.enabled has the value true to create the bean.

2fill in blank

medium

Complete the code to create a bean only if another bean named 'dataSource' exists.

Spring Boot

@Bean
@ConditionalOnBean(name = "[1]")
public Repository repository() {
    return new Repository();
}

Drag options to blanks, or click blank then click option'

Aservice

BdataSource

CcacheManager

DentityManager

Attempts:

3 left

💡 Hint

Common Mistakes

Using a bean name that does not exist causes the bean not to be created.

Confusing bean names like 'entityManager' or 'cacheManager' when the condition is on 'dataSource'.

The @ConditionalOnBean annotation creates the bean only if a bean named dataSource exists in the context.

3fill in blank

hard

Fix the error in the code to create a bean only if a class 'com.example.Service' is present.

Spring Boot

@Bean
@ConditionalOnClass(name = "[1]")
public Service service() {
    return new Service();
}

Drag options to blanks, or click blank then click option'

Acom.example.Service

Bcom.example.services.Service

Cexample.Service

Dcom.example.service

Attempts:

3 left

💡 Hint

Common Mistakes

Using package name only without class name.

Incorrect capitalization or missing parts of the package.

The @ConditionalOnClass annotation requires the full class name including package and class name exactly as com.example.Service.

4fill in blank

hard

Fill both blanks to create a bean only if property 'app.mode' equals 'prod' and a bean named 'cacheManager' exists.

Spring Boot

@Bean
@ConditionalOnProperty(name = "app.mode", havingValue = "[1]")
@ConditionalOnBean(name = "[2]")
public CacheService cacheService() {
    return new CacheService();
}

Drag options to blanks, or click blank then click option'

Aprod

Bdev

CcacheManager

DdataSource

Attempts:

3 left

💡 Hint

Common Mistakes

Using 'dev' instead of 'prod' disables the bean creation.

Checking for a bean named 'dataSource' instead of 'cacheManager'.

The bean cacheService is created only if the property app.mode is 'prod' and the bean named cacheManager exists.

5fill in blank

hard

Fill all three blanks to create a bean only if class 'com.example.Feature' is present, property 'feature.enabled' is 'true', and bean 'featureRepository' exists.

Spring Boot

@Bean
@ConditionalOnClass(name = "[1]")
@ConditionalOnProperty(name = "feature.enabled", havingValue = "[2]")
@ConditionalOnBean(name = "[3]")
public Feature feature() {
    return new Feature();
}

Drag options to blanks, or click blank then click option'

Acom.example.Feature

Btrue

CfeatureRepository

Dcom.example.Features

Attempts:

3 left

💡 Hint

Common Mistakes

Misspelling the class name or package.

Using 'false' instead of 'true' for the property.

Checking for a bean with a wrong name.

The bean feature is created only if the class com.example.Feature is present, the property feature.enabled is 'true', and the bean named featureRepository exists.