Develop Reference

Quote issues reading properties file using fmt:message in JavaScript

I'm using reading text from properties file. But when I'm using it in JavaScript like this:
alert('<fmt:message key="mykey" />');
If there's single quote defined in properties file for this key, there will be an error. If I change the single quotes to double quotes, the error will occur if double quotes defined in properties file.
Any ideas?

You'll have to dynamically escape the string using, for example, Apache commons StringEscapeUtils. You could simply wrap this method into a custom EL function or JSP tag.

You could use the same technique as handlebars: put your messages in <script> tags:
<script type="text/fmt" id="mykey"><fmt:message key="mykey" /></script>
then:
alert(document.getElementById("mykey").innerHTML);
Or, if you're using jQuery:
alert($("#mykey").text());

Output string as html in freemarker

So we are storing html in out data model. I need to output this into a freemarker template:
example:
[#assign value = model.value!]
${value}
value = '<p>This is <a href='somelink'>Some link</a></p>'
I have tried [#noescape] but it throws an error saying there is no escape block. see FREEMARKER: avoid escaping HTML chars. This solution did not work for me.

[#noescape] or <#noescape> is only valid when used inside an [#escape] tag. Your data is probably stored with the HTML encoded. You need to get the backend to un-encode the html.
Otherwise you'll need to do something like...
${value?replace(">", ">")?replace("<", "<")}
But that isn't a good approach because it won't catch all the encoded values and shouldn't be done in the view layer.

Cannot escape a quotation(") character when retriveing a string containg quotation inside a string from DB in jsp

I have saved quotation(") in a string using escape character i database. That is working ok. But when i am retrieving the value in a jsp field from database, the string is being ended at the first quotation it gets in the whole string. I am giving an example below:
Lets take a string that i have stored in database as -
" Hello David. This is a "customer"."
Now, i am somehow need to save the string back from databse into a hidden field in a jsp page like below-
<input type="hidden" name="string_from_database" id="string_from_database" value="<%=some varibale that holds the data from database%>">
issue is -
Part of the string is getting exposed (means it is being written on top of the page) which i do not want. In this case,the below phrase is written on the beginning of the jsp page, which i don't want.
customer".
kindly suggest on how to resolve this issue.

Using this function you could replace the quote marks with the html entity variant ". Here's a simple function for it. Hope it fits into your templating system, but should be easy to modify if not.
function escapeQuotes(str){
return str.replace(/"/g,'"');
}
Here's a working fiddle

Use Jstl rather than scriptlets for further Explanation
use EL - Expression Language (${variable}) to get the Value eg. ${welcome}
<c:out value="${some varibale that holds the data from database}"/>

Java Custom tag containing generated JSTL : not interpreted

I have a custom tag that has no body at all. I'm trying to programmatically replace the empty body with, for simplicity's sake,
[<c:out value="SUCCESS!"/>]
The goal is to see "[SUCCESS!]" displayed by the JSP which uses the tag, but all I see is "[]" and if I look at the generated source code, I can see that the c:out statement is written on the page between the brackets, but not interpreted.
Is there a common way to achieve this ? The final goal will be to use other custom tags instead of the "c:out" tag. The tags/content will come from a database.
I tried different techniques with SimpleTagSupport and BodyTagSupport but none of those were successfull. In fact I'm not sure if it is technically possible to do it, since, the tag has already been interpreted at that time.. But then how should this be done ?

Server tags (like your custom tag or JSTL tags) get transformed to Java code when the JSP is translated into a servlet. For example, the following JSP code:
<c:out value="FooBar" />
gets translated to something like this inside the servlet:
....
OutTag outTag = (OutTag) tagHandlerPool.get(OutTag.class);
outTag.setPageContext(pageContext);
outTag.setParent(null);
outTag.setValue(new String("FooBar"));
int evalOut = outTag.doStartTag();
....
In your custom tags you can call other Java classes/methods and can write HTML code (not JSP code) to the response.
The [<c:out value="SUCCESS!"/>] is not interpreted because at this level it's just a string that gets written directly to the response.

Getting wrong characters in parameter

In files.jsp I am using following anchor and JSTL c:url combination -
<c:url value="downloadfile.jsp" var="dwnUrl" scope="request">
<c:param name="fileType" value="PDF"/>
<c:param name="fileId" value="${file.fileId}"/>
<c:param name="fileName" value="${file.fileName}"/>
</c:url>
Download
On downloadfile.jsp getting the file name value in JavaScript variable as -
selectedFile = <c:out value='${param.fileName}'>
Now, if file name contains some extra character e.g. XYZ 2/3" Technical then on the other page I am getting some different character as - XYZ 2/3#034; Technical
However, if I print request.getParameter("fileName"), its giving correct name. What is wrong?

The <c:out> by default escapes XML entities, such as the doublequote. This is done so to get well-formed XML and to avoid XSS.
To fix this, you should either get rid of <c:out>, since JSP 2.0, EL works perfectly fine in template text as well:
selectedFile = '${param.fileName}';
.. or, if you're still on legacy JSP 1.2 or older, set its escapeXml attribute to false:
selectedFile = '<c:out value="${param.fileName}" escapeXml="false">';
Note that I have added the singlequotes and semicolon to make JS code valid.
Needless to say, you'll need to keep XSS risks in mind if you do so.

The funky characters in your <c:param> values are being URL encoded by <c:url> as they should be. As far as downloadfile.jsp is concerned, the servlet container takes care of URL decoding incoming variables so you don't have to. This is normal behavior and shouldn't pose any problems for you.

If you simply turn escapeXml to false as #BalusC suggests, you will add an XSS vunerability to your page. Instead, you should encode the user input at the time of injection into the destination language, and escape characters that would be evaluated in the destination language. In this case, if the user input contained a single quote character (I'm assuming the string literal in your original example was supposed to be wrapped in single quotes, but the same would be true for double quotes if you were using them), any JavaScript code that followed it would be interpreted by the browser and executed. To safely do what you are trying to do, you should change the line in downloadfile.jsp to:
selectedFile = '${fn:replace(param.fileName, "'", "\'")}';
That will escape only single quotes, which would otherwise end the string literal declaration.
If you were using double quotes, then this would be appropriate:
selectedFile = "${fn:replace(param.fileName, '"', '\"')}";
It is worth noting that escapeXml could be appropriate for escaping JavaScript string literals (and it often is) when the string literal will eventually be dumped into HTML markup. However, in this case, the value should not be XML escaped as it is evaluated in the context of a file path, rather than in the context of HTML.