Up to this point, we’ve been using terms like client and server somewhat loosely. These terms represent fairly specific concepts in the world of distributed computing and Java EE.
A Java EE client can be a console (text) application written in Java, or a GUI application written using the Java Foundation Classes (JFC) and Swing or AWT. These types of clients are often called fat clients because they tend to have a fair amount of supporting code for the user interface.
Java EE clients may also be web-based clients; that is, clients that live inside a browser. Because these clients offload much of their processing to supporting servers, they have very little in the way of supporting code. This type of client is often called a thin client. A thin client may be a purely HTML-based interface, a JavaScript-enriched page, or one that contains a fairly simple applet where a slightly richer user interface is needed.
It would be an oversimplification to describe the application logic called by the Java EE clients as the “server,” although it is true that, from the perspective of the developer of the clientside code, that illusion is in no small way the magic of what the Java EE platform provides. In fact, the Java EE application server is the actual server that connects the client application to the business logic.
The server-side components created by the application developer can be in the form of web components and business components. Web components come in the form of JSPs or Servlets. Business components, in the world of Java EE, are EJBs.
These server-side components rely on the Java EE framework. Java EE provides support for the server-side components in the form of containers.
A Java EE client can be a console (text) application written in Java, or a GUI application written using the Java Foundation Classes (JFC) and Swing or AWT. These types of clients are often called fat clients because they tend to have a fair amount of supporting code for the user interface.
Java EE clients may also be web-based clients; that is, clients that live inside a browser. Because these clients offload much of their processing to supporting servers, they have very little in the way of supporting code. This type of client is often called a thin client. A thin client may be a purely HTML-based interface, a JavaScript-enriched page, or one that contains a fairly simple applet where a slightly richer user interface is needed.
It would be an oversimplification to describe the application logic called by the Java EE clients as the “server,” although it is true that, from the perspective of the developer of the clientside code, that illusion is in no small way the magic of what the Java EE platform provides. In fact, the Java EE application server is the actual server that connects the client application to the business logic.
The server-side components created by the application developer can be in the form of web components and business components. Web components come in the form of JSPs or Servlets. Business components, in the world of Java EE, are EJBs.
These server-side components rely on the Java EE framework. Java EE provides support for the server-side components in the form of containers.
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