Scripting Syntax Error Examples

Let’s look at some examples of problems you need to deal with if you use scripting elements.

Example 16-7 shows a modified version of the page used earlier to illustrate how scripting elements end up in the generated servlet. It has two errors: a semicolon is incorrectly used in the expression, and the closing bracket for the else block in the last scriptlet is missing.

Example 16-7. Invalid semicolon use and missing end bracket (error1.jsp)
<%@ page language="java" contentType="text/html" %>
<%@ page import="java.util.Date" %>
<%!
  private String getGreeting(  ) {
    Date now = new Date(  );
    String greeting = null;
    if (now.getHours(  ) < 12) {
      greeting = "Good morning";
    }
    else if (now.getHours(  ) < 18) {
      greeting = "Good day";
    }
    else {
      greeting = "Good evening";
    }
    return greeting;
  }
%>
<html>
  <head>
    <title>Invalid semicolon use and missing end bracket</title>
  </head>
  <body bgcolor="white">
    <%= getGreeting(  ); %>
    <% if (request.getParameter("name") == null) { %>
      stranger!
    <% } else { %>
      partner!
  
    How are you?
  </body>
</html>

This is the error description Tomcat sends to the browser (with some line breaks added to make it fit the page):

org.apache.jasper.JasperException: Unable to compile class for JSP An error occurred at line: 24 in the jsp file: /ch16/error1.jsp Generated servlet error: D:\jakarta-tomcat-5.0\work\localhost\ora\ch16\error1_jsp.java:67: ')' expected. out.write(String.valueOf(getGreeting( ); )); ^ An error occurred at line: 24 in the jsp file: ...

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