org.mmbase.bridge.jsp.taglib
Class ContextReferrerTag

java.lang.Object
  javax.servlet.jsp.tagext.TagSupport
      javax.servlet.jsp.tagext.BodyTagSupport
          org.mmbase.bridge.jsp.taglib.ContextReferrerTag

All Implemented Interfaces:

javax.servlet.jsp.tagext.BodyTag, javax.servlet.jsp.tagext.IterationTag, java.io.Serializable, javax.servlet.jsp.tagext.Tag

Direct Known Subclasses:

CloudReferrerTag, CloudTag, ContextTag, FormatterTag, ImportTag, ListReferrerTag, LocaleTag, LogTag, ParamTag, PresentTag, RemoveTag, TimerTag, TimeTag, WriteTag, XsltTag

public abstract class ContextReferrerTag

extends javax.servlet.jsp.tagext.BodyTagSupport

If you want to have attributes which obtain the value from a parameter or other context variable, or if you want to be able to refer to other tags, then your tag can extend from this one.

Version:

$Id: ContextReferrerTag.java,v 1.57.2.3 2004/07/23 19:41:09 michiel Exp $

Author:

Michiel Meeuwissen

See Also:

ContextTag, Serialized Form

Field Summary

protected Attribute	contextId
static int	EVAL_BODY EVAL_BODY is EVAL_BODY_INCLUDE or EVAL_BODY_BUFFERED.
protected WriterHelper	helper The helper member is only used by 'Writer' extensions.
protected Attribute	id
protected ContextTag	pageContextTag
protected Attribute	referid
protected Attribute	writerid Which writer to use.

Fields inherited from class javax.servlet.jsp.tagext.BodyTagSupport

bodyContent

Fields inherited from class javax.servlet.jsp.tagext.TagSupport

pageContext

Fields inherited from interface javax.servlet.jsp.tagext.BodyTag

EVAL_BODY_BUFFERED, EVAL_BODY_TAG

Fields inherited from interface javax.servlet.jsp.tagext.IterationTag

EVAL_BODY_AGAIN

Fields inherited from interface javax.servlet.jsp.tagext.Tag

EVAL_BODY_INCLUDE, EVAL_PAGE, SKIP_BODY, SKIP_PAGE

Constructor Summary

ContextReferrerTag()

Method Summary

int	doEndTag()
protected javax.servlet.jsp.tagext.TagSupport	findParentTag(java.lang.Class clazz, java.lang.String id)
javax.servlet.jsp.tagext.TagSupport	findParentTag(java.lang.Class clazz, java.lang.String tagId, boolean exception) Finds a parent tag by class and id.
protected javax.servlet.jsp.tagext.TagSupport	findParentTag(java.lang.String classname, java.lang.String id) Deprecated.
protected javax.servlet.jsp.tagext.TagSupport	findParentTag(java.lang.String classname, java.lang.String id, boolean exception) Deprecated.
Writer	findWriter() Find the parent writer tag.
Writer	findWriter(boolean th)
Attribute	getAttribute(java.lang.String attribute)
protected java.lang.Boolean	getAttributeBoolean(java.lang.String b) Like getAttributeValue but converts the result to a Boolean, and throws an exception if this cannot be done.
protected java.lang.Integer	getAttributeInteger(java.lang.String i) Like getAttributeValue but converts the result to an Integer, and throws an exception if this cannot be done.
protected java.lang.Integer	getAttributeInteger(java.lang.String i, int def)
java.lang.String	getAttributeValue(java.lang.String attribute) Deprecated. Call getAttribute in the set-method and 'toString(tag)' when using it. This is better for perfomrnace and makes sure the impl. works in all servlet containers.
ContentTag	getContentTag() Returns the content-tag in which this context-referrer is in, or a default (compatible with MMBase 1.6) if there is none.
ContextProvider	getContextProvider() Finds the parent context provider.
ContextTag	getContextTag() Finds the parent context tag.
java.lang.String	getId()
java.util.Locale	getLocale()
java.lang.Object	getObject(java.lang.String key) Gets an object from the Context.
javax.servlet.jsp.PageContext	getPageContext()
protected java.lang.String	getReferid()
protected java.lang.String	getString(java.lang.String key) Gets an object from the Context, and returns it as a String.
java.lang.Object	getWriterValue()
void	haveBody()
void	release() Release all allocated resources.
void	setContext(java.lang.String c) Refer to a specific context.
void	setEscape(java.lang.String e)
void	setId(java.lang.String i)
void	setJspvar(java.lang.String j)
void	setPageContext(javax.servlet.jsp.PageContext pc)
void	setReferid(java.lang.String r) ContextReferrers normally can have the attribute 'referid'.
void	setVartype(java.lang.String t)
void	setWrite(java.lang.String w)
void	setWriter(java.lang.String w) Sets the writer attribute.

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

doAfterBody, doInitBody, doStartTag, getBodyContent, getPreviousOut, setBodyContent

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

findAncestorWithClass, getParent, getValue, getValues, removeValue, setParent, setValue

Methods inherited from class java.lang.Object

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

Methods inherited from interface javax.servlet.jsp.tagext.Tag

getParent, setParent

Field Detail

EVAL_BODY

public static int EVAL_BODY

EVAL_BODY is EVAL_BODY_INCLUDE or EVAL_BODY_BUFFERED. It wants to be EVAL_BODY_INCLUDE, but because that often not works, it on default is EVAL_BODY_BUFFERED. This configurable constant might become deprecated, because it is a bit experimental.

pageContextTag

protected ContextTag pageContextTag

contextId

protected Attribute contextId

referid

protected Attribute referid

id

protected Attribute id

writerid

protected Attribute writerid

Which writer to use.

helper

protected final WriterHelper helper

The helper member is only used by 'Writer' extensions.

Constructor Detail

ContextReferrerTag

public ContextReferrerTag()

Method Detail

getPageContext

public javax.servlet.jsp.PageContext getPageContext()

setPageContext

public void setPageContext(javax.servlet.jsp.PageContext pc)

setReferid

public void setReferid(java.lang.String r)
                throws javax.servlet.jsp.JspTagException

ContextReferrers normally can have the attribute 'referid'. If a ContextReferrer has the 'id' attribute it registers its output in the surrounding Context. With 'referid' you can 'repeat' a tag which had the 'id' attribute.

Throws:

javax.servlet.jsp.JspTagException

setId

public void setId(java.lang.String i)

getId

public java.lang.String getId()

getReferid

protected java.lang.String getReferid()
                               throws javax.servlet.jsp.JspTagException

Throws:

javax.servlet.jsp.JspTagException

findWriter

public Writer findWriter()
                  throws javax.servlet.jsp.JspTagException

Find the parent writer tag. It also calls haveBody on this parent tag, so that this knows that it has a body. If a write-tag has a body, then on default it will not write itself, but only communicate itself tot the body's tags.

Throws:

javax.servlet.jsp.JspTagException

findWriter

public Writer findWriter(boolean th)
                  throws javax.servlet.jsp.JspTagException

Throws:

javax.servlet.jsp.JspTagException

Since:

MMBase-1.6.2

setWriter

public void setWriter(java.lang.String w)
               throws javax.servlet.jsp.JspTagException

Sets the writer attribute.

Throws:

javax.servlet.jsp.JspTagException

doEndTag

public int doEndTag()
             throws javax.servlet.jsp.JspTagException

Throws:

javax.servlet.jsp.JspTagException

release

public void release()

Release all allocated resources.

setContext

public void setContext(java.lang.String c)
                throws javax.servlet.jsp.JspTagException

Refer to a specific context. With this you can refer to, and write in, another context then the direct parent (but is must be an ancestor). This is for analogy with other attributes like this.

Throws:

javax.servlet.jsp.JspTagException

getAttributeValue

public java.lang.String getAttributeValue(java.lang.String attribute)
                                   throws javax.servlet.jsp.JspTagException

Deprecated. Call getAttribute in the set-method and 'toString(tag)' when using it. This is better for perfomrnace and makes sure the impl. works in all servlet containers.

Call this function in your set-attribute function. It makes it possible for the user of the taglib to include ids of values stored in the context. The method replaces all occurrences of ${x} and $x, where x is a reference to a attribute value, possibly prefixed with context names. The end of the variable if determined by the closing bracket (${x}) or by the first non ContextIndentifierChar or end of string ($x). Simple aritmetic is possible with ${+...}, and since you can even use $-vars inside ${}, you can do in this way some arithmetic on variables.

Throws:

javax.servlet.jsp.JspTagException

getAttribute

public Attribute getAttribute(java.lang.String attribute)
                       throws javax.servlet.jsp.JspTagException

Throws:

javax.servlet.jsp.JspTagException

Since:

MMBase-1.6.1

getAttributeBoolean

protected java.lang.Boolean getAttributeBoolean(java.lang.String b)
                                         throws javax.servlet.jsp.JspTagException

Like getAttributeValue but converts the result to a Boolean, and throws an exception if this cannot be done.

Throws:

javax.servlet.jsp.JspTagException

getAttributeInteger

protected java.lang.Integer getAttributeInteger(java.lang.String i)
                                         throws javax.servlet.jsp.JspTagException

Like getAttributeValue but converts the result to an Integer, and throws an exception if this cannot be done. It the incoming string evaluates to an empty string, then it will return 0, unless the second optional parameter specifies another default value;

Throws:

javax.servlet.jsp.JspTagException

getAttributeInteger

protected java.lang.Integer getAttributeInteger(java.lang.String i,
                                                int def)
                                         throws javax.servlet.jsp.JspTagException

Throws:

javax.servlet.jsp.JspTagException

findParentTag

protected final javax.servlet.jsp.tagext.TagSupport findParentTag(java.lang.String classname,
                                                                  java.lang.String id,
                                                                  boolean exception)
                                                           throws javax.servlet.jsp.JspTagException

Deprecated.

Throws:

javax.servlet.jsp.JspTagException

See Also:

findParentTag(Class, String, boolean)

findParentTag

public final javax.servlet.jsp.tagext.TagSupport findParentTag(java.lang.Class clazz,
                                                               java.lang.String tagId,
                                                               boolean exception)
                                                        throws javax.servlet.jsp.JspTagException

Finds a parent tag by class and id. This is a base function for 'getContext', but it is handy in itself, so also available for extended classes.

Parameters:

clazz - the class of the Tag to find.

exception - if it has to throw an exception if the parent can not be found (default: yes).

Throws:

javax.servlet.jsp.JspTagException

Since:

MMBase-1.7

findParentTag

protected final javax.servlet.jsp.tagext.TagSupport findParentTag(java.lang.String classname,
                                                                  java.lang.String id)
                                                           throws javax.servlet.jsp.JspTagException

Deprecated.

Throws:

javax.servlet.jsp.JspTagException

findParentTag

protected final javax.servlet.jsp.tagext.TagSupport findParentTag(java.lang.Class clazz,
                                                                  java.lang.String id)
                                                           throws javax.servlet.jsp.JspTagException

Throws:

javax.servlet.jsp.JspTagException

Since:

MMBase-1.7

getContextProvider

public ContextProvider getContextProvider()
                                   throws javax.servlet.jsp.JspTagException

Finds the parent context provider.

Throws:

javax.servlet.jsp.JspTagException

Since:

MMBase-1.7

getContextTag

public ContextTag getContextTag()
                         throws javax.servlet.jsp.JspTagException

Finds the parent context tag. In MMBase 1.7 and higher, normally you would like to use getContextProvider in stead.

Throws:

javax.servlet.jsp.JspTagException

getObject

public java.lang.Object getObject(java.lang.String key)
                           throws javax.servlet.jsp.JspTagException

Gets an object from the Context.

Throws:

javax.servlet.jsp.JspTagException

getString

protected java.lang.String getString(java.lang.String key)
                              throws javax.servlet.jsp.JspTagException

Gets an object from the Context, and returns it as a String. This is not always a simple 'toString'. For example a getString on a Node will return the number, which also uniquely identifies it. If the object is 'not present' then it returns an empty string.

Throws:

javax.servlet.jsp.JspTagException

getContentTag

public ContentTag getContentTag()
                         throws javax.servlet.jsp.JspTagException

Returns the content-tag in which this context-referrer is in, or a default (compatible with MMBase 1.6) if there is none.

Throws:

javax.servlet.jsp.JspTagException

Since:

MMBase-1.7

getLocale

public java.util.Locale getLocale()
                           throws javax.servlet.jsp.JspTagException

Throws:

javax.servlet.jsp.JspTagException

Since:

MMBase-1.7.1

setVartype

public void setVartype(java.lang.String t)
                throws javax.servlet.jsp.JspTagException

Throws:

javax.servlet.jsp.JspTagException

setJspvar

public void setJspvar(java.lang.String j)

setWrite

public final void setWrite(java.lang.String w)
                    throws javax.servlet.jsp.JspTagException

Throws:

javax.servlet.jsp.JspTagException

setEscape

public final void setEscape(java.lang.String e)
                     throws javax.servlet.jsp.JspTagException

Throws:

javax.servlet.jsp.JspTagException

getWriterValue

public final java.lang.Object getWriterValue()

haveBody

public final void haveBody()