Scripting Elements in JSP - Programmingempire

The following article describes Scripting Elements in JSP.

There are three types of scripting elements in a JSP.

Scriptlet: A scriptlet is a block of Java code that is executed when the JSP page is processed. Scriptlets are enclosed in <% and %> tags, and can contain any valid Java code, including variable declarations, loops, conditionals, and method calls. For Example.

<%
int count = 0;
for (inti = 0; i< 10; i++) {
count += i;
  }
%>

Expression: An expression is a dynamic value that is inserted into the HTML output generated by the JSP. Expressions are enclosed in <%= and %> tags, and can contain any valid Java expression, including method calls and variable references. For Example.

<p>The current time is <%= new java.util.Date() %>.</p>

Declaration: A declaration is used to declare instance or class-level variables and methods that can be accessed throughout the JSP page. Declarations are enclosed in <%! and %> tags, and can contain any valid Java code, including variable declarations, method definitions, and class definitions. For Example.

<%! int count = 0; %>
<%
count++;
%>
<p>The count is <%= count %>.</p>

In summary, scriptlets, expressions, and declarations are the three types of scripting elements in a JSP, each used for different purposes such as executing Java code, inserting dynamic values into HTML output, and declaring variables and methods.

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