Traditionally Spring applications were configured using only xml configurations. Later annotations such as @Component came and complemented the xml configuration. However later XML configurations were completely replaced by Java configurations that use annotations such as @Bean.

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Xml configuration

In xml configuration, you use xml to configure beans.

We can load an xml configuration file from a standalone application as:

Below JAX-RS annotations aid in mapping a resource class (a POJO) as a web resource:

• @Path

  • specifies the relative path for a resource class or method.

• @GET, @PUT, @POST, @DELETE and @HEAD

  • specify the HTTP request type of a resource.

• @Produces

  • specifies the response Internet media types (used for content negotiation).

• @Consumes

  • specifies the accepted request Internet media types.

REST follows resource oriented architecture as opposed to the popular service oriented architecture followed by SOAP web services.

Resource-Oriented Architecture has four important concepts:

• Resources,

• their names (URIs),

• their representations and

• the links between them.

Java is one of the most popular programming languages. However, recently many other programming languages have come and some of them even running on top of the Java Virtual Machine (JVM). Many of these languages support newer programming practices like functional programming and comes with a bunch of out of the box functionalities that abstract away most of the low level details from the programmer.

Java 8 has has made some improvements in collections framework such as a new forEach loop, better type inference etc. We will list out those features here.

The forEach method

The default forEach method of the Iterable interface performs the given action for each element of the Iterable until all elements have been processed or the action throws an exception. 

Signature of the methiod is: void forEach(Consumer<? super T> action)