// ========================================================================
// $Id: Page.java,v 1.5 2004/09/23 02:15:15 gregwilkins Exp $
// Copyright 1996-2004 Mort Bay Consulting Pty. Ltd.
// ------------------------------------------------------------------------
// Licensed under the Apache License, Version 2.0 (the "License");
// you may not use this file except in compliance with the License.
// You may obtain a copy of the License at
// http://www.apache.org/licenses/LICENSE-2.0
// Unless required by applicable law or agreed to in writing, software
// distributed under the License is distributed on an "AS IS" BASIS,
// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
// See the License for the specific language governing permissions and
// limitations under the License.
// ========================================================================
package net.lightbody.bmp.proxy.jetty.html;
import java.io.IOException;
import java.io.Writer;
import java.util.Dictionary;
import java.util.Hashtable;
/* --------------------------------------------------------------------- */
/** HTML Page.
* A HTML Page extends composite with the addition of the HTML Header
* tags, fields and elements.
* Furthermore, individual parts of the page may be written or the
* progressive page be output with flush.
* <p>
* Pages contain parameters and named sections. These are used by
* derived Page classes that implement a Look and Feel. Page users
* may add to name sections such as "Margin" or "Footer" and set
* parameters such as "HelpUrl" without knowledge of how the look and feel
* will arrange these. To assist with standard look and feel creation
* Page defines a set of standard names for many common parameters
* and sections.
* <p>
* If named sections are used, the page constructor or completeSections
* must add the named section to the page in the appropriate places.
* If named sections are not added to the page, then they can only be
* written with an explicit call to write(out,"section",end);
* Changes in behaviour to section creation and adding, should be controlled
* via page properties.
* <p>
* @see Composite
* @version $Id: Page.java,v 1.5 2004/09/23 02:15:15 gregwilkins Exp $
* @author Greg Wilkins
*/
public class Page extends Composite
{
/* ----------------------------------------------------------------- */
public static final String
Request="Request",
Response="Response",
Header="Header",
Title="Title",
Section="Section",
HeaderSize="HdrSize", // HeaderSize string suitable for FRAMESET
Footer="Footer",
FooterSize="FtrSize", // FooterSize string suitable for FRAMESET
Content="Content",
ContentSize="CntSize",
Margin="Margin",
MarginSize="MrgSize",
LeftMargin="Left",
LeftMarginSize="LMSize",
RightMargin="Right",
RightMarginSize="RMSize",
Help="Help",
Home="Home",
Heading="Heading",
Up="Up",
Prev="Prev",
Next="Next",
Back="Back",
Target="Target",
BaseUrl="BaseUrl",
FgColour="FgColour",
BgColour="BgColour",
HighlightColour="HlColour",
PageType="PageType",
NoTitle="No Title"
;
/* ----------------------------------------------------------------- */
protected Hashtable properties = new Hashtable(10);
/* ----------------------------------------------------------------- */
Hashtable sections = new Hashtable(10);
private Composite head= new Composite();
private String base="";
private boolean writtenHtmlHead = false;
private boolean writtenBodyTag = false;
/* ----------------------------------------------------------------- */
public Page()
{
this(NoTitle);
}
/* ----------------------------------------------------------------- */
public Page(String title)
{
title(title);
}
/* ----------------------------------------------------------------- */
public Page(String title, String attributes)
{
title(title);
attribute(attributes);
}
/* ----------------------------------------------------------------- */
/** Set page title.
* @return This Page (for chained commands)
*/
public Page title(String title)
{
properties.put(Title,title);
String heading = (String)properties.get(Heading);
if (heading==null||heading.equals(NoTitle))
properties.put(Heading,title);
return this;
}
/* ----------------------------------------------------------------- */
/** Add element or object to the page header.
* @param o The Object to add. If it is a String or Element, it is
* added directly, otherwise toString() is called.
* @return This Page (for chained commands)
*/
public Page addHeader(Object o)
{
head.add("\n");
head.add(o);
return this;
}
/* ----------------------------------------------------------------- */
/** Set page background image.
* @return This Page (for chained commands)
*/
public final Page setBackGroundImage(String bg)
{
attribute("background",bg);
return this;
}
/* ----------------------------------------------------------------- */
/** Set page background color.
* @return This Page (for chained commands)
*/
public final Page setBackGroundColor(String color)
{
properties.put(BgColour,color);
attribute("bgcolor",color);
return this;
}
/* ----------------------------------------------------------------- */
/** Set the URL Base for the Page.
* @param target Default link target, null if none.
* @param href Default absolute href, null if none.
* @return This Page (for chained commands)
*/
public final Page setBase(String target, String href)
{
base="<base " +
((target!=null)?("TARGET=\""+target+"\""):"") +
((href!=null)?("HREF=\""+href+"\""):"") +
">";
return this;
}
/* ----------------------------------------------------------------- */
/** Write the entire page by calling:<br>
* writeHtmlHead(out)<br>
* writeBodyTag(out)<br>
* writeElements(out)<br>
* writeHtmlEnd(out)
*/
public void write(Writer out)
throws IOException
{
writeHtmlHead(out);
writeBodyTag(out);
writeElements(out);
writeHtmlEnd(out);
}
/* ------------------------------------------------------------ */
/** Write HTML page head tags.
* Write tags <HTML><head> .... </head>
*/
public void writeHtmlHead(Writer out)
throws IOException
{
if (!writtenHtmlHead)
{
writtenHtmlHead=true;
completeSections();
out.write("<html><head>");
String title=(String)properties.get(Title);
if (title!=null && title.length()>0 && !title.equals(NoTitle))
out.write("<title>"+title+"</title>");
head.write(out);
out.write(base);
out.write("\n</head>\n");
}
}
/* ------------------------------------------------------------ */
/** Write HTML page body tag.
* Write tags <BODY page attributes>.
*/
public void writeBodyTag(Writer out)
throws IOException
{
if (!writtenBodyTag)
{
writtenBodyTag = true;
out.write("<body "+attributes()+">\n");
}
}
/* ------------------------------------------------------------ */
/** Write end BODY and end HTML tags.
*/
public void writeHtmlEnd(Writer out)
throws IOException
{
out.write("\n</body>\n");
out.write("</html>\n");
}
/* ------------------------------------------------------------ */
/** Write any body elements of the page.
*/
public void writeElements(Writer out)
throws IOException
{
super.write(out);
}
/* ------------------------------------------------------------ */
/** Write page section.
* The page is written containing only the named section.
* If a head and bodyTag have not been written, then they
* are written before the section. If endHtml is true, the
* end HTML tag is also written.
* If the named section is Content and it cannot be found,
* then the normal page contents are written.
*/
public void write(Writer out,
String section,
boolean endHtml)
throws IOException
{
writeHtmlHead(out);
writeBodyTag(out);
Composite s = getSection(section);
if (s==null)
{
if (section.equals(Content))
writeElements(out);
}
else
s.write(out);
if (endHtml)
writeHtmlEnd(out);
out.flush();
}
/* ------------------------------------------------------------ */
/* Flush the current contents of the page.
* writeHtmlEnd() is not called and should either be
* explicitly called or called via an eventual call to write()
*/
public void flush(Writer out)
throws IOException
{
writeHtmlHead(out);
writeBodyTag(out);
super.flush(out);
}
/* ------------------------------------------------------------ */
/* Reset the page status to not written.
* This is useful if you want to send a page more than once.
*/
public void rewind()
{
writtenHtmlHead = false;
writtenBodyTag = false;
}
/* ------------------------------------------------------------ */
/** Access the page properties. It is up to a derived Page class
* to interpret these properties.
*/
public Dictionary properties()
{
return properties;
}
/* ------------------------------------------------------------ */
/** Return the preferred FrameSet to be used with a specialized Page.
* The Frames will be named after the sections they are to
* contain.
* The default implementation returns null
*/
public FrameSet frameSet()
{
return null;
}
/* ------------------------------------------------------------ */
/** Set a composite as a named section. Other Page users may.
* add to the section by calling addTo(). It is up to the section
* creator to add the section to the page in it appropriate position.
*/
public void setSection(String section, Composite composite)
{
sections.put(section,composite);
}
/* ------------------------------------------------------------ */
/** Set a composite as a named section and add it to the.
* contents of the page
*/
public void addSection(String section, Composite composite)
{
sections.put(section,composite);
add(composite);
}
/* ------------------------------------------------------------ */
/** Get a composite as a named section.
*/
public Composite getSection(String section)
{
return (Composite)sections.get(section);
}
/* ------------------------------------------------------------ */
/** Add content to a named sections. If the named section cannot.
* be found, the content is added to the page.
*/
public void addTo(String section, Object element)
{
Composite s = (Composite)sections.get(section);
if (s==null)
add(element);
else
s.add(element);
}
/* ------------------------------------------------------------ */
/** This call back is called just before writeHeaders() actually
* writes the HTML page headers. It can be implemented by a derived
* Page class to complete a named section after the rest of the Page
* has been created and appropriate properties set.
*/
protected void completeSections()
{
}
}