Embedded JPA Entities are nothing new to the JPA standard. By defining Embedded JPA Entities, you can define a common data type for your application. Unlike regular JPA Entities which generally follow a table per entity mapping strategy. Embedded JPA Entities are stored as additional columns in the underlying relational database table. If you’re using […]Continue reading
In the 1.3.0 release of Spring Boot and new module is available called Spring Boot Developer Tools. This new Spring Boot module is aimed at improving developer productivity in building Spring Web Applications. When you’re developing a web application in Java, or really any programming language, a common workflow is to code, compile, deploy, and then […]Continue reading
Core to the Spring Framework is a concept of bean factories. Spring bean factories follow the concepts of the GoF Factory Design Pattern to provide the requestor fully configured objects. Under the covers when the Spring Framework is performing dependency injection on your beans, Spring itself will use bean factories to obtain a fully configured […]Continue reading
During the creation of Spring Beans, you can obtain the name of the bean by implementing the Spring interface – BeanNameAware. Then during the creation of Spring beans, the Spring Context will inject the name it has set for the bean. This is the name the Spring Bean factory will use as a reference to […]Continue reading
A real common task is to display a list of objects fetched from the database in a HTML table on a webpage. Thymeleaf has a handy tag which allows us to iterate over a list of objects, and generate HTML code to display a table row for each object. The HTML generated really does not “need” […]Continue reading
When Autowiring Spring Beans, a common exception is a BeanCreationException. This means that Spring found a bean to create, but was unable to fulfill the dependencies needed to create this this Spring bean. Here is an example of a BeanCreationException: BeanCreationException Exception in thread “main” org.springframework.beans.factory.BeanCreationException: Error creating bean with name ‘helloController’: Injection of autowired […]Continue reading
When Autowiring Spring Beans, a common error is to see a NoSuchBeanDefinitionException. Here is an example of the NoSuchBeanDefinitionException you may see thrown by the Spring context: NoSuchBeanDefinitionException Exception in thread “main” org.springframework.beans.factory.NoSuchBeanDefinitionException: No qualifying bean of type [guru.springframework.controllers.HelloController] is defined at org.springframework.beans.factory.support.DefaultListableBeanFactory.getBean(DefaultListableBeanFactory.java:372) at org.springframework.beans.factory.support.DefaultListableBeanFactory.getBean(DefaultListableBeanFactory.java:332) at org.springframework.context.support.AbstractApplicationContext.getBean(AbstractApplicationContext.java:1060) By default, Spring will Autowire beans by type. You […]Continue reading
Sorting an ArrayList is a common task in Java development. ArrayList is one of the most commonly used collection classes of the Java Collection Framework. Java provides a number of different ways to sort ArrayLists. In this post, we’ll explore the different ways to sort ArrayLists, and review best practices you should keep in mind. […]Continue reading
At the heart of the Spring Framework is its support of dependency injection through its Inversion of Control container. In this video, I look at using some of the advanced autowire features of Spring. @Primary By default, Spring will autowire by type. When you have more than one Spring Bean of a given type, you can […]Continue reading
As a Java programmer, you will often need to work with date and time. In this post, we will learn how to get the current time of the day in Java applications. In Java, there are several ways for this and the primary classes that programmers typically use are the Date and Calendar classes. You can use both […]Continue reading
