Can u explain init() method is used in servlet for initialization then constructor also there for initializing variables.then what makes the difference between init() and default constructor in servlets?

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Using init() only advisable than default constructor because we cannot initialize servlet using constructor because servlets are not directly instantiated by javacode, instead container create instance and keep it in pool. Container create instance of servlet using Java reflection in presence of no...
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Using init() only advisable than default constructor because we cannot initialize servlet using constructor because servlets are not directly instantiated by javacode, instead container create instance and keep it in pool. Container create instance of servlet using Java reflection in presence of no argument constructor. Java Compiler not add default no argument constructor... more» read less
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IIT BTech for Java, data structure and algorythm classes

Servlet implementation classes can have constructor but they should be using init() method to initialise Servlet because of two reasons, first you cannot declare constructors on interface in Java, which means you cannot enforce this requirement to any class which implements Servlet interface and second,...
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Servlet implementation classes can have constructor but they should be using init() method to initialise Servlet because of two reasons, first you cannot declare constructors on interface in Java, which means you cannot enforce this requirement to any class which implements Servlet interface and second, Servlet require ServletConfig object for initialisation which is created by container as it also has reference of ServletContext object, which is also created by container. read less
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Java Trainer

servelt() cannot be called directly. Servlet will be instantiated implicitly by Servelt container, in this case we cannot provide initial values using constructor, hence we must go for init() method to initialize
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init() method is more robust and broader in scope than the default constructor. init() is part of the servlet life cycle and required to be invoked once before taking any requests and its invoked by the container and it has access to ServletConfig as well. In contrast, default constructor can not take...
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init() method is more robust and broader in scope than the default constructor. init() is part of the servlet life cycle and required to be invoked once before taking any requests and its invoked by the container and it has access to ServletConfig as well. In contrast, default constructor can not take such parameters while initializing and its invoked everytime the instantiation happens. Hope it clears the difference. read less
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Servlet implementation classes can have constructor but they should be using init() method to initialize Servlet because of two reasons, first you cannot declare constructors on interface in Java, which means you cannot enforce this requirement to any class which implements Servlet interface and second,...
read more
Servlet implementation classes can have constructor but they should be using init() method to initialize Servlet because of two reasons, first you cannot declare constructors on interface in Java, which means you cannot enforce this requirement to any class which implements Servlet interface and second, Servlet require ServletConfig object for initialization which is created by container as it also has reference of ServletContext object, which is also created by container. read less
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Servlet implementation classes can have constructor but they should be using init() to innitilize servlet.
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init()..i.e.,initialization method used for,in order to place code which need to be execute whenever first request is generated...like database connection opening code ,file open code,datamember intialization code etc...
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init method can be overridden whereas we cannot override a constructor. If the we have to initialize then init method will be overridden
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Both init() and constructors are used for initializing servlets but it's better to use init() because it receives "ServletConfig" parameter which can have data from "web.xml" and this has useful parameters need to initialize the servlet. However, even if you dont choose to use a parameterized constructor...
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Both init() and constructors are used for initializing servlets but it's better to use init() because it receives "ServletConfig" parameter which can have data from "web.xml" and this has useful parameters need to initialize the servlet. However, even if you dont choose to use a parameterized constructor , a default constructor will be called by default when the servlet ibject is created. So both are used. read less
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Expert in java training and self development class of IT students

Using init() only advisable than default constructor because we cannot initialize servlet using constructor because servlets are not directly instantiated by javacode, instead container create instance and keep it in pool. Container create instance of servlet using Java reflection in presence of no...
read more
Using init() only advisable than default constructor because we cannot initialize servlet using constructor because servlets are not directly instantiated by javacode, instead container create instance and keep it in pool. Container create instance of servlet using Java reflection in presence of no argument constructor. Java Compiler not add default no argument constructor if the class has parameterized constructor. read less
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