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Steps To Delete Servletconfig Object In Servlet Problem

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You may run into an error indicating how to get the servletconfig object in the servlet. There are several ways to solve this problem. We’ll talk about this a little later.

 

 

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  1. ServletConfig Interface
  2. ServletConfig Interface Methods
  3. How to get an object from ServletConfig
  4. Syntax for providing a servlet initialization parameter
  5. Example for ServletConfig getting initialization parameter
  6. Example for ServletConfig to get all initialization parameters.

For each servlet, a ServletConfig object is created by the web container. This object can be used to get configuration information from the web.xml file.

If the configuration information in the web.xml file has changed, the servlet does not need to be changed. This makes it easier to manage the web application if some content changes from time to time.

ServletConfig Advantage

The main advantage of ServletConfig is that you don’t need to change the servlet file if the information in the web.xml file changes.

ServletConfig Interface Methods

  1. public String getInitParameter (String name): Returns the parameter value for the given parameter name.
  2. public enumeration getInitParameterNames (): Returns an enumeration of all initialization parameter names.
  3. public String getServletName (): Returns the name of the servlet.
  4. public ServletContext getServletContext (): returns an object from ServletContext.

How To Get An Object From ServletConfig

  1. The getServletConfig () method of the servlet interface returns an object from the ServletConfig.

Syntax of the getServletConfig () method

Example GetServletConfig () Method


Syntax For Providing A Servlet Initialization Parameter

The init-param subelement of the servlet is used to specify the initialization parameter of the servlet.


Example For ServletConfig Getting Initialization Parameter

In this example, we get the initialization parameter from the web.xml file and output this information to the servlet.

DemoServlet.java
web.xml


Download this example (developed in the Myeclipse IDE)
Download this example (developed in Eclipse IDE)
Download this example (developed in Netbeans IDE)

Example For ServletConfig To Get All Initialization Parameters

In this example, we get all the initialization parameters from the web.xml file and output this information to the servlet.

DemoServlet.java
web.xml


Download this example (designed byfound in the Myeclipse IDE)
Download this example (developed in Eclipse IDE)
Download this example (developed in Netbeans IDE)

Next topicServletContext

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continue >><< previous

  1. ServletConfig Interface
  2. ServletConfig Interface Methods
  3. How to get an object from ServletConfig
  4. Syntax for providing a servlet initialization parameter
  5. Example for ServletConfig getting initialization parameter
  6. Example for ServletConfig to get all initialization parameters.

Download this example (developed in the Myeclipse IDE)
Download this example (developed in Eclipse IDE)
Download this example (developed in Netbeans IDE)Download this example (developed in the Myeclipse IDE)
Download this example (developed in Eclipse IDE)
Download this example (developed in Netbeans IDE)Next topicServletContext<< previouscontinue >>

1.1 What Is ServletConfig?

ServletConfig is an interface in the Servlet API that is used to initialize a single servlet in a web application through a servlet container. In descriptor p web.xml deployments developers define a servlet initialization parameter for this servlet. Information is declared in the tag in a name-value pair. The ServletConfig interface signature is as follows:

 public interface ServletConfig

Developers can use ServletConfig and to configure any servlet in the J2EE environment.

1.1.1 Some points to know about the ServletConfig interface

  • For each servlet run, the servlet container creates a ServletConfig object that is used by the programmer to read the servlet-specific data declared in web.xml
  • ServletConfig is the interface of the javax.servlet
  • package.

  • The getServletConfig () method of the GenericServlet class returns an object of the ServletConfig class.
  • The ServletConfig object created by the container for a particular servlet cannot read data from another servlet
  • The ServletConfig object refers to a Servlet. Another possibility is that if 100 servlet objects are executing in a container, implicitlyo 100 ServletConfig objects are created to communicate with the servlet.
  • If the container destroys a Servlet object, the corresponding ServletConfig object is also destroyed
  • The programmer can use the ServletConfig object to read the tags of the servlets.
  • The data in the tag are called initialization parameters.
  • 1.1.2 Sample Code

    Let’s take a look at a simple code snippet that follows the ServletConfig implementation.

       ServletConfigTest   com.jcg.servlet.ServletConfigTest     topicName    Difference between ServletConfig and ServletContext  

    how to get servletconfig object in servlet

    In the servlet, we get the value of this parameter using the getInitParameter ("param-name") method, i.e. H.

     Line name = getServletConfig (). getInitParameter ("theme name");

    ServletConfig Interface Methods

    public String getInitParameter (String name): Returns the value of the specified parameter as a string, or null if the specified parameter does not exist in web.xml.
    public enumeration getInitParameterNames (): Returns an enumeration of all parameter names.
    public String getServletName (): returns the name of the servlet instanceentry.
    public ServletContext getServletContext (): returns an object from ServletContext.

     

     

    Initializing Servlets – OVGU

    You can get it in the servlet’s initialization method if the servlet needs to load additional classes from the application. This is a handy rewriting method for initializing servlets. In this case, you need to get the ServletConfig object in the body of the method and use it to get the initialization parameters.

    How to get ServletContext and ServletConfig object in a …

    Implement the Spring * Aware interfaces for these ServletContextAware and ServletConfigAware interfaces. …Using @Autowired annotation with servletContext and ServletConfig bean variables.

    Reading Initialization Parameters – Documentation | Perforce

    Implementing the Spring * Aware interfaces for these ServletContextAware and ServletConfigAware interfaces. …Using @Autowired annotation with servletContext and ServletConfig bean variables.