Question

I have a JSP where in a text area i am reading the String array of a whole sentence and printing it line by line. No i want to highlight some patter in the line in BOLD and red color font. e.g. if the line which is being read contains pattern “error” (it can be a single word or a part of a word like “initializationerror” or “”), i t will be highlighted in BOLD and red color. The rest of the line will be print as it is.

Below is the code snippet:

<table border="2">
<% 
    if(session.getAttribute("Result") != null)
    {
        String Result = (String) session.getAttribute("Result");
        if(Result.length() != 0)
        {
            String[] split_EOL = Result.split("\n");
%>
            <tr align="center"> 
                <td>
                    // Text area start here 
                    <textarea rows="50" cols="100" readonly="yes">   
<%
                        for(int i = 0; i < split_EOL.length; i++)
                        {
                            out.println(split_EOL[i]);
                            out.println(" ");
                        }
%>
                    </textarea>
                 </td>
             </tr>
<%
         }
    }
%>
</table>

Please help

I tried the following:

<textarea rows="50" cols="100" readonly="yes"> 
<% 
     for(int i=0;i<split_EOL.length ; i++){ 
     out.println(split_EOL[i].replaceAll("\\b\\w*"+Pattern+"\\w*\\b", "<b>$0</b>"));   
     out.println(" "); 

                                          }
%> 
</textarea> 

here Pattern = ERROR….. but it displays like this

95323:[<b>ERROR</b>] Logger not set 

even i trued to display some word in bold in out.println but it didnt render the bold tags:

 out.println("<b>"+Pattern+"</b>");%>

displays only

<b>ERROR</b>

Answer 1

You can replace the pattern \b\w*error\w*\b with a <span class="error-string">$0</span>

out.println(split_EOL[i].replaceAll("\\b\\w*error\\w*\\b", "<span class=\"error-string\">$0</span>"));

and define in CSS

error-string {
    color: red;
    font-weight: bold;
}

If you need a case insensitive search, you can prefix your pattern with (?i), see Pattern – Special constructs.