org.mmbase.bridge.jsp.taglib
Class AbstractNodeListTag

java.lang.Object
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  +--javax.servlet.jsp.tagext.TagSupport
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        +--javax.servlet.jsp.tagext.BodyTagSupport
              |
              +--org.mmbase.bridge.jsp.taglib.ContextReferrerTag
                    |
                    +--org.mmbase.bridge.jsp.taglib.CloudReferrerTag
                          |
                          +--org.mmbase.bridge.jsp.taglib.AbstractNodeProviderTag
                                |
                                +--org.mmbase.bridge.jsp.taglib.AbstractNodeListTag

All Implemented Interfaces:

javax.servlet.jsp.tagext.BodyTag, ListItemInfo, NodeProvider, java.io.Serializable, javax.servlet.jsp.tagext.Tag, TagIdentifier

Direct Known Subclasses:

ListNodesTag, ListTag, RelatedNodesTag

public abstract class AbstractNodeListTag

extends AbstractNodeProviderTag

implements javax.servlet.jsp.tagext.BodyTag, ListItemInfo

AbstractNodeListTag, provides basic functionality for listing objects stored in MMBase

Author:

Kees Jongenburger, Michiel Meeuwissen, Pierre van Rooden

See Also:

Serialized Form

Field Summary

protected boolean	changed Determines whether a field in sortedString changed during iteration.
protected int	currentItemIndex The current item
protected java.lang.String	directionString Holds the direction to sort the list on (per field in sortedString).
protected int	listSize The actual size of the list.
protected int	max The maximum number of elements in a list.
protected int	offset The offset of the elements that are returned in a list.
protected NodeIterator	returnValues Data member to hold an iterationof the values to return.
protected java.lang.String	sortedString Holds the list of fields to sort the list on.
protected java.lang.String	whereString Holds the clause used to filter the list.

Fields inherited from class org.mmbase.bridge.jsp.taglib.AbstractNodeProviderTag

fields

Fields inherited from class org.mmbase.bridge.jsp.taglib.ContextReferrerTag

pageContextTag, referid

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

bodyContent

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

id, pageContext

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

EVAL_BODY_TAG

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

EVAL_BODY_INCLUDE, EVAL_PAGE, SKIP_BODY, SKIP_PAGE

Constructor Summary

AbstractNodeListTag()

Method Summary

int	doAfterBody()
void	doInitBody()
abstract int	doStartTag()
int	getIndex()
boolean	isChanged() If you order a list, then the 'changed' property will be true if the field on which you order changed value.
boolean	isFirst()
boolean	isLast()
void	setConstraints(java.lang.String where) Sets the selection query
void	setDirections(java.lang.String directions) Sets the direction to sort on
void	setMax(int m) Sets the list maximum with an integer argument.
void	setMax(java.lang.String m) Set the list maximum
void	setOffset(int o)
void	setOffset(java.lang.String o) Set the list offset
void	setOrderby(java.lang.String sorted) Sets the fields to sort on.
protected int	setReturnValues(NodeList nodes) Creates the node iterator and sets appropriate variables (i.e.
protected int	setReturnValues(NodeList nodes, boolean trim) Creates the node iterator and sets appropriate variables (i.e.
int	size()

Methods inherited from class org.mmbase.bridge.jsp.taglib.AbstractNodeProviderTag

doEndTag, fillVars, getNodeVar, setFields, setJspvar, setNodeVar

Methods inherited from class org.mmbase.bridge.jsp.taglib.CloudReferrerTag

findCloudProvider, getCloudContext, getCloudProviderVar, setCloud

Methods inherited from class org.mmbase.bridge.jsp.taglib.ContextReferrerTag

findParentTag, findParentTag, getAttributeValue, getContextTag, getContextTag, getReferid, getReferIdValue, release, setContext, setPageContext, setReferid, stringSplitter, stringSplitter

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

getBodyContent, getPreviousOut, setBodyContent

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

findAncestorWithClass, getId, getParent, getValue, getValues, removeValue, setId, 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.BodyTag

setBodyContent

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

doEndTag, getParent, release, setPageContext, setParent

Methods inherited from interface org.mmbase.bridge.jsp.taglib.TagIdentifier

getId

Field Detail

sortedString

protected java.lang.String sortedString

Holds the list of fields to sort the list on. The sort itself is implementation specific.

directionString

protected java.lang.String directionString

Holds the direction to sort the list on (per field in sortedString). The sort itself is implementation specific.

whereString

protected java.lang.String whereString

Holds the clause used to filter the list. This is either a SQL-clause, with MMBase fields in brackets, a altavista-like search, preceded with the keyword ALTA, or a MMBase database node search, preceded with the keyord MMNODE. The filter itself is implementation specific (not all lists may implement this!).

max

protected int max

The maximum number of elements in a list. Setting the list size to conform to this maximum is implementation specific.

offset

protected int offset

The offset of the elements that are returned in a list. Setting the list to conform to this ofsset is implementation specific.

changed

protected boolean changed

Determines whether a field in sortedString changed during iteration.

returnValues

protected NodeIterator returnValues

Data member to hold an iterationof the values to return. This variable is set in setReturnValues(NodeList), which should be called from doStartTag(), and will be used to fill the return variables for every iteration.

listSize

protected int listSize

The actual size of the list.

currentItemIndex

protected int currentItemIndex

The current item

Constructor Detail

AbstractNodeListTag

public AbstractNodeListTag()

Method Detail

getIndex

public int getIndex()

Specified by:

getIndex in interface ListItemInfo

Following copied from interface: org.mmbase.bridge.jsp.taglib.ListItemInfo

Returns:

the index of the current item in a list

setOrderby

public void setOrderby(java.lang.String sorted)
                throws javax.servlet.jsp.JspTagException

Sets the fields to sort on.

Parameters:

sorted - A comma separated list of fields on witch the returned nodes should be sorted

setDirections

public void setDirections(java.lang.String directions)
                   throws javax.servlet.jsp.JspTagException

Sets the direction to sort on

Parameters:

direction - the selection query for the object we are looking for direction

setMax

public void setMax(java.lang.String m)
            throws javax.servlet.jsp.JspTagException

Set the list maximum

Parameters:

max - the max number of values returned

setMax

public void setMax(int m)

Sets the list maximum with an integer argument. Tomcat needs this if you feed it with an rtexprvalue of type int.

setOffset

public void setOffset(java.lang.String o)
               throws javax.servlet.jsp.JspTagException

Set the list offset

Parameters:

max - the max number of values returned

setOffset

public void setOffset(int o)

setConstraints

public void setConstraints(java.lang.String where)
                    throws javax.servlet.jsp.JspTagException

Sets the selection query

Parameters:

where - the selection query

doStartTag

public abstract int doStartTag()
                        throws javax.servlet.jsp.JspTagException

Specified by:

doStartTag in interface javax.servlet.jsp.tagext.Tag

Overrides:

doStartTag in class javax.servlet.jsp.tagext.BodyTagSupport

setReturnValues

protected int setReturnValues(NodeList nodes)

Creates the node iterator and sets appropriate variables (i.e. listsize) froma passed node list. The list is assumed to be already sorted and trimmed.

Parameters:

nodes - the nodelist to create the iterator from

Returns:

EVAL_BODY_TAG if the resulting list is not empty, SKIP_BODY if the list is empty. THis value should be passed as the result of {

setReturnValues

protected int setReturnValues(NodeList nodes,
                              boolean trim)

Creates the node iterator and sets appropriate variables (i.e. listsize). Takes a node list, and trims it using the offset and max attributes if so indicated. The list is assumed to be already sorted.

Parameters:

nodes - the nodelist to create the iterator from

trim - if true, trim the list using offset and max (if false, it is assumed the calling routine already did so)

Returns:

EVAL_BODY_TAG if the resulting list is not empty, SKIP_BODY if the list is empty. THis value should be passed as the result of {

doAfterBody

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

Specified by:

doAfterBody in interface javax.servlet.jsp.tagext.BodyTag

Overrides:

doAfterBody in class javax.servlet.jsp.tagext.BodyTagSupport

doInitBody

public void doInitBody()
                throws javax.servlet.jsp.JspTagException

Specified by:

doInitBody in interface javax.servlet.jsp.tagext.BodyTag

Overrides:

doInitBody in class AbstractNodeProviderTag

isFirst

public boolean isFirst()

isChanged

public boolean isChanged()

If you order a list, then the 'changed' property will be true if the field on which you order changed value.

Specified by:

isChanged in interface ListItemInfo

Following copied from interface: org.mmbase.bridge.jsp.taglib.ListItemInfo

Returns:

a boolean indicating wether the field on which was sorted is changed.

size

public int size()

Specified by:

size in interface ListItemInfo

Following copied from interface: org.mmbase.bridge.jsp.taglib.ListItemInfo

Returns:

the size of the list

isLast

public boolean isLast()