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<TITLE>Getting a Request Parameter in a JSP Page (Java Developers Almanac Example)
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  <h3>e1053. Getting a Request Parameter in a JSP Page</h3>

In a GET request, the request parameters are taken from the query
string (the data following the question mark on the URL).  For
example, the URL <code>http://hostname.com?p1=v1&amp;p2=v2</code> contains two
request parameters -  - <code>p1</code> and <code>p2</code>.  In a POST request, the
request parameters are taken from both query string and the posted
data which is encoded in the body of the request.

<P> This example demonstrates how to include the value of a request
parameter in the generated output:


<pre>    Hello &lt;b&gt;&lt;%= request.getParameter(<font color="#0066ff"><i>"name"</i></font>) %&gt;&lt;/b&gt;!
</pre>
If the page was accessed with the URL:

<pre>    http://hostname.com/mywebapp/mypage.jsp?name=John+Smith
</pre>
the resulting output would be:

<pre>    Hello &lt;b&gt;John Smith&lt;/b&gt;!
</pre>
If name is not specified on the query string, the output would be:

<pre>    Hello &lt;b&gt;null&lt;/b&gt;!
</pre>
This example uses the value of a query parameter in a scriptlet:

<pre>    &lt;%
        if (request.getParameter(<font color="#0066ff"><i>"name"</i></font>) == null) {
            out.println("Please enter your name.");
        } else {
            out.println("Hello &lt;b&gt;"+request.getParameter(<font color="#0066ff"><i>i</i></font>)+"&lt;/b&gt;!");
        }
    %&gt;
</pre>
See also <a href="../javax.servlet.jsp.jstl.core/getparam.html" class="eglink"><b>e1066</b> Getting a Request Parameter Using JSTL in a JSP Page</a>.

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            &nbsp;<b>Related Examples</b></font></td>
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e1054. <a class="eglink" href="include.jsp.html?l=rel">
    Including a File in a JSP Page
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<br>

e1055. <a class="eglink" href="caller.jsp.html?l=rel">
    Passing Parameters to Another JSP Page
</a>
<br>

e1056. <a class="eglink" href="usebean.jsp.html?l=rel">
    Using a Bean in a JSP Page
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        See also: 
<a class="eglink" href="/egs/javax.servlet.jsp/pkg.html?l=rel#Java%20Server%20Pages">
    Java Server Pages
</a>&nbsp;&nbsp;

<a class="eglink" href="/egs/javax.servlet.jsp/pkg.html?l=rel#Java%20Server%20Pages%20Headers">
    Java Server Pages Headers
</a>&nbsp;&nbsp;

<a class="eglink" href="/egs/javax.servlet.jsp/pkg.html?l=rel#Java%20Server%20Pages%20Output">
    Java Server Pages Output
</a>&nbsp;&nbsp;

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