Image View servlet v. 1.6


Simple component you may use for images view. For example, in your JSP files you may decide to show images that are outside of the web root. How to use it:

1) download ImageServlet.jar and save it in WEB-INF/lib

2) describe this servlet in web.xml:
 


    <servlet>
     <servlet-name>Image</servlet-name>
     <servlet-class>com.jsos.image.ImageServlet</servlet-class>
    </servlet>

3) add a mapping if you need:
 


     <servlet-mapping>
      <servlet-name>Image</servlet-name>
      <url-pattern>/servlet/Image</url-pattern>
     </servlet-mapping>

and you can use some like this in your JSP files:
 


<img src="/servlet/Image?c:\mydir\image.gif" width="125">

also you can describe an image file as an initial parameter. Parameter name is file:
 


    <servlet>
     <servlet-name>Image</servlet-name>
     <servlet-class>com.jsos.image.ImageServlet</servlet-class>
     <init-param>
      <param-name>file</param-name>
      <param-value>c:\\mydir\\image.gif</param-value>
     </init-param>
    </servlet>

The usage in this case is:
<img src="/servlet/Image" width="125">

The second initial parameter is dir. You can describe here a base directory for image files and pass a short file name in your query string:
 


    <servlet>
     <servlet-name>Image</servlet-name>
     <servlet-class>com.jsos.image.ImageServlet</servlet-class>
     <init-param>
      <param-name>dir</param-name>
      <param-value>c:/mydir</param-value>
     </init-param>
    </servlet>

and now /servlet/Image?image.gif will read c:/mydir/image.gif file.

You can set also an optional initial parameter expires. This parameter describes a caching time (in seconds) for the images (client side cache). E.g. client side cache for 24 hours:
 


    <servlet>
     <servlet-name>Image</servlet-name>
     <servlet-class>com.jsos.image.ImageServlet</servlet-class>
     <init-param>
      <param-name>dir</param-name>
      <param-value>c:/mydir</param-value>
     </init-param>
     <init-param>
      <param-name>expires</param-name>
      <param-value>86400</param-value>
     </init-param>
    </servlet>

For downloading:

servlet: ImageServlet.jar  

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