The Spring Framework is an open source application framework and Inversion of Control container for the Java platform.
This page lists down all tutorials on this website available on this topic. This page will be updated everytime, I will write any post on Spring 3. Feel free to suggest topics you want to read more on.
Hello world application
Learn to create basic Spring mvc application using maven for dependency management.
The beans in spring container can be created in five scopes. singleton, prototype, request, session and global-session. Learn them in detail.
Spring framework provides following 4 ways for controlling life cycle events of bean:
- InitializingBean and DisposableBean callback interfaces
- Other Aware interfaces for specific behavior
- custom init() and destroy() methods in bean configuration file
- @PostConstruct and @PreDestroy annotations
Read more in above post.
In spring framework, setting bean dependencies in configuration files is a good practice to follow, but the spring container is also 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. Learn how to do it.
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. Learn in detail.
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. Learn more.
Autowiring by constructor is similar to byType, but applies to constructor arguments. In autowire enabled bean, it will look for class type of constructor arguments, and then do a autowire by type on all constructor arguments. Learn more.
Autowiring by autodetect uses either of two modes i.e. constructor or byType modes. First it will try to look for valid constructor with arguments, If found the constructor mode is chosen. If there is no constructor defined in bean, or explicit default no-args constructor is present, the autowire byType mode is chosen. Learn more.
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 instantiate other beans. Learn how to create beans using Spring FactoryBean.
In you want to create a bean in the Spring 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.
If you have final static fields in some bean and you want to use those references as beans in application context file to inject into another beans, you can do so using <util:constant> tag.
Many times you would like to load external resources or files (e.g. text files, XML files, properties file, or image files) into your spring application context. Spring’s resource loader provides a unified getResource() method for you to retrieve an external resource by a resource path.
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. Learn to create such post processors using BeanPostProcessor interface class.
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. Learn how to support i10n using ResourceBundleMessageSource class.
Sometimes in your spring application, you may want to add capability of listening specific events so that you can process these events as per application logic. Let’s learn how we can achieve this publish and listen events in your spring application.
With @Component, @Repository, @Service and @Controller annotations in place and after enabling automatic component scanning, spring will automatically import the beans into the container so you don’t have to define them explicitly with XML. These annotations are called Stereotype annotations as well.
In real life application, you will not be interested in checking all the bean properties configured in your context files. Rather you would like to check if particular set of properties have been set or not in some specific beans only. Spring’s dependency checking feature using “dependency-check” attribute, will not able to help you in this case. So solve this problem, you can use @Required annotation.
Spring beans, dependencies, and the services needed by beans are specified in xml configuration files or annotations. The XML configuration files, however, are verbose and more clean. If not planned and written correctly, it becomes very hard to manage in big projects.
In this article, I will show you 13 best practices for writing spring XML configurations.
Inversion of control and dependency injection
In traditional programming, the flow of the business logic is determined by objects that are statically assigned to one another. With inversion of control, the flow depends on the object graph that is instantiated by the assembler and is made possible by object interactions being defined through abstractions. The binding process is achieved through dependency injection. Read this post for a detailed information.
Spring 3 gave the freedom to move bean definitions out of xml files. Now, you can give bean definitions in your java files itself. This is called JavaConfig feature (using @Configuration annotation). In this post, we will see a example of this type of configuration.
Every good open source framework allows to write the exception handlers in such a way that you can separate then from your application code. Well, Spring 3 also allows you to do so using annotation @ExceptionHandler. Lets see how all this works.
Interceptors, as we know, are special web programming constructs which gets invoked every time when a certain pre-configured web request is made. They are always the most important and basic functional segments designed very early in product life cycle, due to their importance. In this post, I am writing about using these interceptors in your spring 3 application. This post is very short to focus only on interceptor configuration and usage.
In this post, I am writing about adding JSTL support to Spring 3 using maven build tool.
Internationalization is the process of designing a software application so that it can be adapted to various languages and regions without engineering changes.Learn to make Spring 3 application supported in multiple languages and locales.
Spring security is another major module in spring distribution and is supported only for applications developed using JDK 1.5 or higher. In this post, I will demostrate how to secure you spring 3 based web application. The scope of this tutorial is to:
- Only authorized user should be able to access edit employee screen.
- Unauthorized users should be presented with login screen.
- Successful credentials should forward to edit employee screen.
- Unsuccessful credentials should forward to access denied screen.
- There should be a link for logout of the application.
Commonly there are two ways of storing user details for authentication i.e. using custom user service implementation or spring provided jdbc user service. In this post, I am showing the way to use second approach i.e. jdbc user service.
Basic authentication is often used with stateless clients which pass their credentials on each request. It’s quite common to use it in combination with form-based authentication where an application is used through both a browser-based user interface and as a web-service. Lets learn how to configure this in a simple spring 3 based web application.
Commonly there are two ways of storing user details for authentication i.e. using custom user service implementation or spring provided jdbc user service. In this post, I am showing the way to use first approach i.e. using custom user service implementation. In summary, UserDetailsService interface is used in order to lookup the username, password and GrantedAuthorities for any given user. Lets see everything in action.
@PreAuthorize and @Secured annotations are used for method level security in Spring 3 application. It’s different from other mechanism in sense that others are used for URL based security. Lets see how it works.
In this example, user has been pre-authenticated in any other application and get into your web application using site minder. Site minder sends a request header about pre-authenticated user which you can utilize to further authorize the user inside your application. You do not need to further authenticate the user, just verify user roles from database and provide appropriate access inside application.
Most security implementations usually are on controller or model layer of MVC. Spring provides security in view layer also. It is mostly needed when we want to hide certain links or buttons based on user’s role so that he will not be able to access that functionality. It is done using taglibs. Lets learn how to achieve it.
Web services support
A step by step guide for creating a RESTful web service application using Spring 3 mvc. This post covers all requited dependencies, annotations applied and a working application demo, which you can download for free.
This tutorial is focused on usage of Hibernate with Spring 3 framework. I will show that how a basic end to end application flow looks like as a result of this integration.
In previous example, lots of people struggled in resolving maven dependencies. In this example, I have added all required jar files in project sourcecode itself. Additionally, I have advanced the version of spring from 3.0.5 to 3.2.5.RELEASE.
3rd party integration
HornetQ is an open source project to build a multi-protocol, embeddable, very high performance, clustered, asynchronous messaging system. HornetQ comes with a lot of flexibility to be configured with some existing application frameworks. In this post, I am demonstrating the usage of HornetQ with Spring 3.
A simple example to show how to send emails with Spring 3
AbstractRoutingDataSource is very useful feature in spring framework if you do have a design which permits multiple databases based on certain criteria which may change for each user request. An example can be use of database. You can use a particular database when user belongs to certain locale and switch to another locale if user belongs to another locale.
Unit testing and related
The main motive of this post to describe the way to build fully populated authentication object programmatically and then use it in unit testing and possibly in application code itself.