simple error due to use of double quotes in a jsp file

Question

I have the following line of code in a JSP File in my web app that is giving an error:

<jsp:setProperty name="db" property="userName" value="<%=request.getParameter("userName")%>"/> 

The error message that I get is:

org.apache.jasper.JasperException: /loginbean.jsp(6,59) Attribute value request.getParameter("userName") is quoted with " which must be escaped when used within the value

What I read on some sites is that characters like ' (single quote) or " (double quote) need to be prefixed with an escape sequence \ (backslash) if they are to be used.

However, when I try and prefix the double quotes (around the word userName) with backslash, I immediately get the following error- "Illegal Character \92- Unclosed String Literal"

How do I resolve this problem?

Answer 1

You should use single quotes on the value parameter, ie:

value='<%=request.getParameter("userName")%>' 

or set the org.apache.jasper.compiler.Parser.STRICT_QUOTE_ESCAPING parameter to false as described here:

http://blogs.sourceallies.com/2009/10/strict-quote-escaping-in-tomcat/

Answer 2

If you are using Tomcat 8.5+, the property org.apache.jasper.compiler.Parser.STRICT_QUOTE_ESCAPING=false will not be acknowledged.

I was able to set the property successfully in {TOMCAT_ROOT}/conf/web.xml by adding the following within the <servlet> block:

<init-param>     <param-name>strictQuoteEscaping</param-name>     <param-value>false</param-value> </init-param>