org.apache.xalan.client

Class XSLTProcessorApplet


public class XSLTProcessorApplet
extends Applet

Provides applet host for the XSLT processor. To perform transformations on an HTML client:
  1. Use an <applet> tag to embed this applet in the HTML client.
  2. Use the DocumentURL and StyleURL PARAM tags or the setDocumentURL(String) and setStyleURL(String) methods to specify the XML source document and XSL stylesheet.
  3. Call the getHtmlText() method (or one of the transformToHtml() methods) to perform the transformation and return the result as a String.
This class extends Applet which ultimately causes this class to implement Serializable. This is a serious restriction on this class. All fields that are not transient and not static are written-out/read-in during serialization. So even private fields essentially become part of the API. Developers need to take care when modifying fields.

Constructor Summary

XSLTProcessorApplet()
The XSLTProcessorApplet constructor takes no arguments.

Method Summary

void
destroy()
Cleanup; called when applet is terminated and unloaded.
String
escapeString(String s)
Given a String containing markup, escape the markup so it can be displayed in the browser.
void
freeCache()
The processor keeps a cache of the source and style trees, so call this method if they have changed or you want to do garbage collection.
String
getAppletInfo()
Get basic information about the applet
String
getHtmlText()
Assuming the stylesheet URL and the input XML URL have been set, perform the transformation and return the result as a String.
String[][]
getParameterInfo()
Get descriptions of the applet parameters.
String
getResultTreeAsText()
Get the HTML result Tree as a text string suitable for display in a browser.
String
getSourceTreeAsText()
Get the XML source Tree as a text string suitable for display in a browser.
String
getStyleTreeAsText()
Get the XSL style Tree as a text string suitable for display in a browser.
String
getTreeAsText(String treeURL)
Get an XML document (or stylesheet)
void
init()
Standard applet initialization.
void
paint(Graphics g)
Do not call; this applet contains no UI or visual components.
void
setDocumentURL(String urlString)
Set the URL to the XML document that will be transformed with the XSL stylesheet.
void
setStyleSheetAttribute(String nameOfIDAttrOfElemToModify, String elemId, String attrName, String value)
Set an attribute in the stylesheet, which gives the ability to have some dynamic selection control.
void
setStyleURL(String urlString)
Set the URL to the XSL stylesheet that will be used to transform the input XML.
void
setStylesheetParam(String key, String expr)
Submit a stylesheet parameter.
void
start()
Automatically called when the HTML client containing the applet loads.
void
stop()
Automatically called when the HTML page containing the applet is no longer on the screen.
String
transformToHtml(String doc)
Process a document and a stylesheet and return the transformation result.
String
transformToHtml(String doc, String style)
Process a document and a stylesheet and return the transformation result.

Constructor Details

XSLTProcessorApplet

public XSLTProcessorApplet()
The XSLTProcessorApplet constructor takes no arguments.

Method Details

destroy

public void destroy()
Cleanup; called when applet is terminated and unloaded.

escapeString

public String escapeString(String s)
Given a String containing markup, escape the markup so it can be displayed in the browser.
Parameters:
s - String to escape The escaped string.

freeCache

public void freeCache()
The processor keeps a cache of the source and style trees, so call this method if they have changed or you want to do garbage collection.

getAppletInfo

public String getAppletInfo()
Get basic information about the applet
Returns:
A String with the applet name and author.

getHtmlText

public String getHtmlText()
Assuming the stylesheet URL and the input XML URL have been set, perform the transformation and return the result as a String.
Returns:
A string that contains the contents pointed to by the URL.

getParameterInfo

public String[][] getParameterInfo()
Get descriptions of the applet parameters.
Returns:
A two-dimensional array of Strings with Name, Type, and Description for each parameter.

getResultTreeAsText

public String getResultTreeAsText()
            throws Exception
Get the HTML result Tree as a text string suitable for display in a browser. Note that this is for display of the XML itself, not for rendering of HTML by the browser.
Returns:
Transformation result as unmarked text.

getSourceTreeAsText

public String getSourceTreeAsText()
            throws Exception
Get the XML source Tree as a text string suitable for display in a browser. Note that this is for display of the XML itself, not for rendering of HTML by the browser.
Returns:
XML source document as a string.

getStyleTreeAsText

public String getStyleTreeAsText()
            throws Exception
Get the XSL style Tree as a text string suitable for display in a browser. Note that this is for display of the XML itself, not for rendering of HTML by the browser.
Returns:
The XSL stylesheet as a string.

getTreeAsText

public String getTreeAsText(String treeURL)
            throws IOException
Get an XML document (or stylesheet)
Parameters:
treeURL - valid URL string for the document.
Returns:
document

init

public void init()
Standard applet initialization.

paint

public void paint(Graphics g)
Do not call; this applet contains no UI or visual components.

setDocumentURL

public void setDocumentURL(String urlString)
Set the URL to the XML document that will be transformed with the XSL stylesheet. No processing is done yet.
Parameters:
urlString - valid URL string for XML document.

setStyleSheetAttribute

public void setStyleSheetAttribute(String nameOfIDAttrOfElemToModify,
                                   String elemId,
                                   String attrName,
                                   String value)
Set an attribute in the stylesheet, which gives the ability to have some dynamic selection control.
Parameters:
nameOfIDAttrOfElemToModify - The name of an attribute to search for a unique id.
elemId - The unique ID to look for.
attrName - Once the element is found, the name of the attribute to set.
value - The value to set the attribute to.

setStyleURL

public void setStyleURL(String urlString)
Set the URL to the XSL stylesheet that will be used to transform the input XML. No processing is done yet.
Parameters:
urlString - valid URL string for XSL stylesheet.

setStylesheetParam

public void setStylesheetParam(String key,
                               String expr)
Submit a stylesheet parameter.
Parameters:
key - stylesheet parameter key
expr - the parameter expression to be submitted.
See Also:
javax.xml.transform.Transformer.setParameter(String,Object)

start

public void start()
Automatically called when the HTML client containing the applet loads. This method starts execution of the applet thread.

stop

public void stop()
Automatically called when the HTML page containing the applet is no longer on the screen. Stops execution of the applet thread.

transformToHtml

public String transformToHtml(String doc)
Process a document and a stylesheet and return the transformation result. Use the xsl:stylesheet PI to find the document, if one exists.
Parameters:
doc - URL string to XML document containing an xsl:stylesheet PI.
Returns:
HTML transformation result

transformToHtml

public String transformToHtml(String doc,
                              String style)
Process a document and a stylesheet and return the transformation result. If one of these is null, the existing value (of a previous transformation) is not affected.
Parameters:
doc - URL string to XML document
style - URL string to XSL stylesheet
Returns:
HTML transformation result

Copyright B) 2005 Apache XML Project. All Rights Reserved.