How to use Encode.forHtml() in a javascript file?

Question

I need to use the Encode.forHtml() in a js file. i'm using the jar Recommended by OWASP - encoder-1.2.jar i'm following the details given in this page https://www.owasp.org/index.php/OWASP_Java_Encoder_Project#tab=Use_the_Java_Encoder_Project

Here all the examples are shown with Scriptlets. I know scriptlets can be used only in jsp. But i want to use the Encode.forHtml() in a js file. so can someone please help me and explain how i can use it a js file.

i tried the following but it didnt work

sample.js
function test1_outsidejsp()
{
 var test = "testforEncode";
 var msg = Encode.forJavaScriptBlock(test);
 alert(msg);
}

PS: There is no problem with the jar. i used the Encode.forHtml() from a script written inside the JSP and it works fine. i have also imported the jar to the jsp

<%@page import="org.owasp.encoder.Encode" %>

This is the script inside the jsp (this is working fine)

<%String test="testing"; %>
<script type="text/javascript">
function testfn_insidejsp()
{
 var msg = "<%= Encode.forJavaScriptBlock(test) %>";
 alert(msg);
}
</script>

I need to know how to write that without the scriptlet in a js file.

Answer 1

If you are not planning on using any other server-side ESAPI features, you may be better off using ESAPI for JavaScript rather than ESAPI for Java, which is what it sounds like you are trying to use.