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<TITLE>Running Java Code in a JSP Page (Java Developers Almanac Example)
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<META CONTENT="Patrick Chan" NAME="AUTHOR">
<META CONTENT="Code Examples from The Java Developers Almanac 1.4" NAME="DESCRIPTION">
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<h1>The Java Developers Almanac 1.4</h1>
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<A HREF="../index.html">List of Packages</A>
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<A HREF="../javax.servlet.jsp/pkg.html">javax.servlet.jsp</A><font color="#666666" class="xsmall-font">
[18 examples]
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<B><A HREF="../javax.servlet.jsp/pkg.html#Java Server Pages">Java Server Pages</A></B><font color="#666666" class="xsmall-font">
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<h3>e1047. Running Java Code in a JSP Page</h3>
Java code fragments in a JSP page is called a scriptlet. This example
demonstrates how to include scriptlets in a JSP page. Use the
<code>out</code> variable to add text to the generated output:
<pre> <%
double rand = Math.random();
if (rand < .1) {
out.println("you win!");
} else {
out.println("try again");
}
%>
</pre>
This example defines a method that can be used in a scriptlet in the page:
<pre> <%!
String getMsg() {
double rand = Math.random();
if (rand < .1) {
return "you win!";
} else {
return "try again";
}
}
%>
<%
// Use the method
out.println(getMsg());
%>
</pre>
There are a number of implicit objects available to scriptlets -
<code>application</code>, <code>config</code>, <code>exception</code>, <code>out</code>,
<code>pageContext</code>, <code>request</code>, <code>response</code>, and <code>session</code>.
These implicit objects are described in the JSP 1.2 Specification
available at http://java.sun.com.
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<b>Related Examples</b></font></td>
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e1046. <a class="eglink" href="basic.html?l=rel">
The Quintessential JSP Page
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e1048. <a class="eglink" href="attr.html?l=rel">
Saving Data in a JSP Page
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e1049. <a class="eglink" href="myform.jsp.html?l=rel">
Implementing a Form in a JSP Page
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e1050. <a class="eglink" href="myformts.jsp.html?l=rel">
Implementing a Form That Prevents Duplicate Submissions in a JSP Page
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e1051. <a class="eglink" href="precompile.html?l=rel">
Precompiling a JSP Page
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e1052. <a class="eglink" href="nosession.html?l=rel">
Preventing the Creation of a Session 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%20Headers">
Java Server Pages Headers
</a>
<a class="eglink" href="/egs/javax.servlet.jsp/pkg.html?l=rel#Java%20Server%20Pages%20Input">
Java Server Pages Input
</a>
<a class="eglink" href="/egs/javax.servlet.jsp/pkg.html?l=rel#Java%20Server%20Pages%20Output">
Java Server Pages Output
</a>
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