Module com.aoapps.encoding.taglib

Package com.aoapps.encoding.taglib

Class EncodingFilteredTag

java.lang.Object

javax.servlet.jsp.tagext.SimpleTagSupport

com.aoapps.encoding.taglib.EncodingFilteredTag

All Implemented Interfaces:

JspTag, SimpleTag

Direct Known Subclasses:

EncodingTag, JavaScriptTag, JsonTag, LdJsonTag, MysqlTag, PsqlTag, ShTag, StyleTag, TextTag, UrlTag, XhtmlAttributeTag, XhtmlTag

public abstract class EncodingFilteredTag
extends SimpleTagSupport

An implementation of SimpleTag that automatically validates its content and automatically encodes its output correctly given its context. It also validates its own output when used in a non-validating context. For higher performance, it filters the output from its body instead of buffering.

The content validation is primarily focused on making sure the contained data is properly encoded. This is to avoid data corruption or intermingling of data and code. It does not go through great lengths such as ensuring that XHTML Strict is valid or JavaScript will run correctly.

In additional to checking that its contents are well behaved, it also is well behaved for its container by properly encoding its output for its context. To determine its context, it uses the content type of the currently registered RequestEncodingContext to perform proper encoding. If it fails to find any such context, it uses the content type of the HttpServletResponse.

Finally, if no existing RequestEncodingContext is found, this will validate its own output against the content type of the HttpServletResponse to make sure it is well-behaved.

Author:

AO Industries, Inc.

Constructor Summary

Constructors

Constructor	Description
EncodingFilteredTag()

Method Summary

Modifier and Type	Method	Description
void	doTag()	Deprecated. You should probably be implementing in doTag(java.io.Writer)
protected void	doTag(Writer out)	Once the out JspWriter has been replaced to output the proper content type, this version of doTag() is called.
abstract MediaType	getContentType()	Gets the type of data that is contained by this tag.
protected void	setMediaEncoderOptions(MediaEncoder mediaEncoder)	Sets the media encoder options.
protected void	writeEncoderPrefix(MediaEncoder mediaEncoder, Writer out)
protected void	writeEncoderSuffix(MediaEncoder mediaEncoder, Writer out, boolean trim)
protected void	writePrefix(MediaType containerType, Writer out)	Writes any prefix in the container's media type.
protected void	writeSuffix(MediaType containerType, Writer out)	Writes any suffix in the container's media type.

Methods inherited from class javax.servlet.jsp.tagext.SimpleTagSupport

findAncestorWithClass, getJspBody, getJspContext, getParent, setJspBody, setJspContext, setParent

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Constructor Details

EncodingFilteredTag

public EncodingFilteredTag()

Method Details

getContentType

public abstract MediaType getContentType()

Gets the type of data that is contained by this tag. This is used to determine the correct encoder. This is also the output type.

doTag

@Deprecated
public void doTag()
           throws JspException,
IOException

Deprecated.

You should probably be implementing in doTag(java.io.Writer)

Specified by:

doTag in interface SimpleTag

Overrides:

doTag in class SimpleTagSupport

Throws:

JspException

IOException

See Also:

• doTag(java.io.Writer)

writePrefix

protected void writePrefix(MediaType containerType,
 Writer out)
                    throws JspException,
IOException

Writes any prefix in the container's media type. The output must be valid for the provided type.

This default implementation prints nothing.

Parameters:

out - Validates all characters against the container media type. Already optimized via Coercion.optimize(java.io.Writer, com.aoapps.lang.io.Encoder).

Throws:

JspException

IOException

setMediaEncoderOptions

protected void setMediaEncoderOptions(MediaEncoder mediaEncoder)

Sets the media encoder options. This is how subclass tag attributes can effect the encoding.

writeEncoderPrefix

protected void writeEncoderPrefix(MediaEncoder mediaEncoder,
 Writer out)
                           throws JspException,
IOException

Parameters:

out - Validates all characters against the container media type. Already optimized via Coercion.optimize(java.io.Writer, com.aoapps.lang.io.Encoder).

Throws:

JspException

IOException

doTag

protected void doTag(Writer out)
              throws JspException,
IOException

Once the out JspWriter has been replaced to output the proper content type, this version of doTag() is called.

This implementation invokes JspFragment.invoke(java.io.Writer) of the JSP body, if present.

Parameters:

out - Validates all characters against the content type. Already optimized via Coercion.optimize(java.io.Writer, com.aoapps.lang.io.Encoder).

Throws:

JspException

IOException

writeEncoderSuffix

protected void writeEncoderSuffix(MediaEncoder mediaEncoder,
 Writer out,
 boolean trim)
                           throws JspException,
IOException

Parameters:

out - Validates all characters against the container media type. Already optimized via Coercion.optimize(java.io.Writer, com.aoapps.lang.io.Encoder).

Throws:

JspException

IOException

writeSuffix

protected void writeSuffix(MediaType containerType,
 Writer out)
                    throws JspException,
IOException

Writes any suffix in the container's media type. The output must be valid for the provided type.

This default implementation prints nothing.

Parameters:

out - Validates all characters against the container media type. Already optimized via Coercion.optimize(java.io.Writer, com.aoapps.lang.io.Encoder).

Throws:

JspException

IOException