bundles/org.apache.jasper.glassfish/src/org/apache/jasper/compiler/JspConfig.java
public boolean isJspPage(String uri) throws JasperException {

        init();
        if (jspProperties == null) {
            return false;
        }

        String uriPath = null;
        int index = uri.lastIndexOf('/');
        if (index >=0 ) {
            uriPath = uri.substring(0, index+1);
        }
        String uriExtension = null;
        index = uri.lastIndexOf('.');
        if (index >=0) {
            uriExtension = uri.substring(index+1);
        }

        for (JspPropertyGroup jpg: jspProperties) {

            JspProperty jp = jpg.getJspProperty();

            String extension = jpg.getExtension();
            String path = jpg.getPath();

            if (extension == null) {
                if (uri.equals(path)) {
                    // There is an exact match
                    return true;
                }
            } else {
                if ((path == null || path.equals(uriPath)) &&
                    (extension.equals("*") || extension.equals(uriExtension))) {
                    // Matches *, *.ext, /p/*, or /p/*.ext
                    return true;
                }
            }
        }
        return false;
    }
public boolean isJspPage(String uri) throws JasperException {

        init();
        if (jspProperties == null) {
            return false;
        }

        String uriPath = null;
        int index = uri.lastIndexOf('/');
        if (index >=0 ) {
            uriPath = uri.substring(0, index+1);
        }
        String uriExtension = null;
        index = uri.lastIndexOf('.');
        if (index >=0) {
            uriExtension = uri.substring(index+1);
        }

        for (JspPropertyGroup jpg: jspProperties) {

            JspProperty jp = jpg.getJspProperty();

            String extension = jpg.getExtension();
            String path = jpg.getPath();

            if (extension == null) {
                if (uri.equals(path)) {
                    // There is an exact match
                    return true;
                }
            } else {
                if ((path == null || path.equals(uriPath)) &&
                    (extension.equals("*") || extension.equals(uriExtension))) {
                    // Matches *, *.ext, /p/*, or /p/*.ext
                    return true;
                }
            }
        }
        return false;
    }
To find out if an uri matches an url pattern in jsp config.  If so,
then the uri is a JSP page.  This is used primarily for jspc.