Spring Boot

In this post, we explore a sample OpenAPI YAML file, which serves as a blueprint for creating RESTful web services within a Spring Boot application. The provided sample OpenAPI file…

In this blog post, we'll explore the process of generating an OpenAPI YAML file for an existing REST API within a Spring Boot application. The OpenAPI YAML file serves as…

We’ll see a warning message “o.s.s.c.bcrypt.BCryptPasswordEncoder : Encoded password does not look like BCrypt” in the spring boot console logs. We’ll see a pattern that the user has not been…

In spring boot security application, this error message “o.s.s.c.bcrypt.BCryptPasswordEncoder : Empty encoded password” is seen often. The user is not allowed to login to the application by security authentication failure.…

In the spring boot security application, The error message “Exception in thread “main” java.lang.IllegalArgumentException: Bad strength” is seen when the application starts. The BCryptPasswordEncoder is throwing this exception as it…

Auto configurations are one of the best features at spring boot. Spring boot supports auto-configured datasource. The credentials for the database are included in application.properties. Spring boot builds a datasource…

The javax.json.bind.JsonbException: JSON Binding provider org.eclipse.yasson.JsonBindingProvider not found exception occurs when the java.json.bind maven dependency is added and JSON bind implementation dependency is not added in the spring boot maven.…

The ReflectionUtils can not access a member of class with modifiers “private” exception occurs when the default constructor or method is configured as private in the java bean class. If…

The javax.json.bind.JsonbException: Cannot create instance of a class: class, No default constructor found. exception occurs when no default constructor is found in the java bean class. The spring boot default…

The javax.json.bind.JsonbException: Can’t deserialize JSON array into: class exception occurs when you try to convert json string data to a java object. If the json string contains an array of…

In the spring boot web application development, you may need to use Application Context to handle loaded beans.The Application context contains all the references to the loaded beans. Spring boot…

The Spring Boot exception "org.springframework.beans.factory.NoSuchBeanDefinitionException: No qualifying bean of type available" occurs when attempting to auto-wire a bean in another class, but the bean is either not available or not…

The spring boot exception org.springframework.beans.factory.NoSuchBeanDefinitionException: No bean named available and org.springframework.beans.factory.NoSuchBeanDefinitionException: No bean named is defined happens when you try to access a bean that is not available or is…

The spring boot exception IllegalStateException: Ambiguous mapping. Cannot map method occurs when two methods in the rest controller class are configured with the same request mapping url. Two methods in…

The required a bean of type ‘org.springframework.web.client.RestTemplate’ that could not be located. spring boot occurs when the RestTemplate is auto-wired without bean creation. The RestTemplate cannot be auto-wired unless the…

com.mysql.cj.jdbc.exceptions.CommunicationsException: Communications link failure com.mysql.jdbc.exceptions.jdbc4.CommunicationsException: Communications link failure The last packet sent successfully to the server was 0 milliseconds ago. The driver has not received any packets from the server.…

The database exception Cannot load driver class: com.mysql.jdbc.Driver occurs if there is a disparity between mysql driver class, mysql driver jar version and mysql database version. The java application attempts…

Failed to configure a DataSource: ‘url’ attribute is not specified and no embedded datasource could be configured exception occurs when the datasource url is not configured in the spring boot…

The exception “java.sql.SQLSyntaxErrorException: Access denied for user ‘root’@’localhost’ to database ‘testdb’” is thrown if you are using mysql database first time or newly installed. If you start the spring boot…

The spring boot application creates database connection in startup. The EntityManager class is responsible for basic CRUD database operation. If the creation of EntityManger is failed, then this error is…