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    <p>Servlet object has a well-defined life cycle where creation and initialization steps are distinct. Usually you don't want to do heavy and unreliable work in constructors, e.g. getting DB connection pool or initializing cache. You have a chance to do it after a Servlet object is successfully created.</p> <p>Also, here <a href="http://oreilly.com/catalog/jservlet/chapter/ch03.html" rel="noreferrer">http://oreilly.com/catalog/jservlet/chapter/ch03.html</a> is a historical reason:</p> <blockquote> <p>The init() method is typically used to perform servlet initialization--creating or loading objects that are used by the servlet in the handling of its requests. <strong>Why not use a constructor instead?</strong> Well, in JDK 1.0 (for which servlets were originally written), constructors for dynamically loaded Java classes (such as servlets) couldn't accept arguments. </p> <p>So, in order to provide a new servlet any information about itself and its environment, a server had to call a servlet's init() method and pass along an object that implements the ServletConfig interface. </p> <p>Also, Java doesn't allow interfaces to declare constructors. This means that the javax.servlet.Servlet interface cannot declare a constructor that accepts a ServletConfig parameter. It has to declare another method, like init(). It's still possible, of course, for you to define constructors for your servlets, but in the constructor you don't have access to the ServletConfig object or the ability to throw a ServletException.</p> </blockquote>
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    1. POwhy we can't initialize a servlet using constructor itself?
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    1. USleopoldkot
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    1. COThank you leopoldkot
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Guidance
A row detail

Detail views are divided into sections. All the information in the data section comes from columns in the selected row. The other sections display data from other, related rows.

Related data can be related in a to-one or a to-many fashion. Captions of data related in a to-many fashion link to a list view showing a filtered view of the table.

Try moving around until you find a non-empty to-many entry and click on the label to get to one. You can move back to the root by clicking on the database name in the header.

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