I have tried to collect these spring interview questions which you may face into your next technical interview. For other spring modules, I will share interview questions and answers separately. I will really appreciate if you can suggest more similar spring interview questions which you have faced in your previous interviews and you consider them […]
Spring Property Editor – CustomEditorConfigurer Example
A property editor is a feature of the JavaBeans API for converting property values to and from text values. Each property editor is designed for a certain type of property only. You may wish to employ property editors to simplify your bean configurations. In this tutorial, we will learn to configure spring’s build-in CustomDateEditor class […]
Spring Pub Sub – Application Events
Learn to use create publisher-subscriber based events in Spring applications. Spring has inbuilt support for creaing application events, publish them and then listen to it in event handlers. There are a few simple guidelines to follow to create / listen application events: the event should extend ApplicationEvent the publisher should inject an ApplicationEventPublisher object the […]
Spring Resource Bundle MessageSource Example
For an application to support internationalization, it requires the capability of resolving text messages for different locales. Spring’s application context is able to resolve text messages for a target locale by their keys. Typically, the messages for one locale should be stored in one separate properties file. This properties file is called a resource bundle. […]
Spring BeanPostProcessor Example
A bean post processor allows additional processing before and after the bean initialization callback method. The main characteristic of a bean post processor is that it will process all the bean instances in the IoC container one by one, not just a single bean instance. Typically, bean post processors are used for checking the validity […]
Spring ResourceLoader example – Load resource files in Spring
Learn different ways to load external resources or files (e.g. text files, XML files, properties file, or image files) into your Spring application context. Spring ResourceLoader provides a unified getResource() method for you to retrieve an external resource by a resource path. 1. Spring Resource interface represents a resource Resource is a general interface in […]
Spring util:constant to refer final static field references
Learn to inject final static fields in some Spring bean into another beans using <util:constant> tag. Spring util:constant Example Logically, you will beans in below given manner. It has two static final fields ie. MANAGER and DIRECTOR. You would like to use above fields in EmployeeTypeWrapper class as below: Where EmployeeTypeWrapper looks like this. Demo […]
Spring static factory-method example
In Spring framework, if you want to create a bean by invoking a static factory-method, whose purpose is to encapsulate the object-creation process in a static method then you could use factory-method attribute. Read More : Spring FactoryBean Static factory method example If you want to create different EmployeeDTO objects based on it’s designation using […]
Spring @Required Annotation
In a production-scale application, there may be hundreds or thousands of beans declared in the IoC container, and the dependencies between them are often very complicated. One of the shortcomings of setter injection is that it’s very hard for you to check if all required properties have been set or not. Using “dependency-check” attribute of […]
Spring FactoryBean Example
A factory bean is a bean that serves as a factory for creating other beans within the IoC container. Conceptually, a factory bean is very similar to a factory method, but it is a Spring-specific bean that can be identified by the Spring IoC container during bean construction and can be used by container to […]
Spring @Component, @Repository and @Service Annotations
In spring autowiring, @Autowired annotation handles only wiring part. We still have to define the beans so the container is aware of them and can inject them for you. With @Component, @Repository, @Service and @Controller annotations in place and automatic component scanning enabled, Spring will automatically import the beans into the container and inject to […]
[Solved] java.lang.ClassNotFoundException: org.springframework.web.context.ContextLoaderListener
If you are working on a web application based on spring which requires use of org.springframework.web.context.ContextLoaderListener in web.xml file and you are getting this exception when you start the server. This exception is more likely when you are working on eclipse or possibly on other such IDE. Exception log trace will look like this: Solution […]
Spring version-less schema for latest version
If you have worked on Spring framework projects, then you must have seen spring context configuration files (e.g. applicationContext.xml) where in header you specify the schema references (.xsd) for various spring modules. In schema references, we mention the xml namespace and as well as schema version number. Well specifying schema version number is not mandatory […]
Spring 3 – Internationalization (i18n) Support Example
Internationalization is the process of designing a software application so that it can be adapted to various languages and regions without engineering changes. The term is frequently abbreviated as i18n (where 18 stands for the number of letters between the first i and last n in internationalization). Above definition essentially means making changes in your […]
Spring send email example – JavaMailSender example
Learn to send emails using Spring framework provided JavaMailSender interface. Here is a step by step example for sending email via gmail smtp server, using Spring’s JavaMailSender interface. We will use javax.mail maven dependency to send emails while configuring mail properties in JavaMailSenderImpl class which implements JavaMailSender interface. Read More: Send Email using Gmail SMTP […]
Spring Bean Autowiring – @Autowired
In Spring framework, declaring bean dependencies in configuration files is a good practice to follow, so the Spring container is able to autowire relationships between collaborating beans. This means that it is possible to automatically let Spring resolve collaborators (other beans) for your bean by inspecting the contents of the BeanFactory. The autowiring functionality has […]
Spring Bean Autowire by Autodetect
Practically bean dependencies are explicitly set in bean configuration files and it is really is a good practice to follow. But Spring is capable of automatically resolving dependencies at runtime. This automatic resolution of bean dependencies is also called autowiring. This type of bean dependencies can also be referred to as collaborating beans or just […]
Spring Autowiring by Constructor
In Spring framework, autowiring by constructor is similar to byType, but applies to constructor arguments. In autowire enabled bean, it look for class type of constructor arguments, and then do a autowire by type on all constructor arguments. Please note that if there isn’t exactly one bean of the constructor argument type in the container, […]
Spring Autowiring by Name
In Spring framework, autowiring by name allows a property to be autowired such that it will inspect the container and look for a bean named exactly the same as the property which needs to be autowired. For example, if you have a bean definition which is set to autowire by name, and it contains a […]
Spring Autowiring byType
In Spring framework, autowiring by type allows a property to be autowired – if there is exactly one bean of the property type in the container. If there is more than one, a fatal exception is thrown, and this indicates that you may not use byType autowiring for that bean. If there are no matching […]