TagInfo (Java EE 5 SDK)

javax.servlet.jsp.tagext Class TagInfo

java.lang.Object
  javax.servlet.jsp.tagext.TagInfo

public class TagInfo

extends Object

Tag information for a tag in a Tag Library; This class is instantiated from the Tag Library Descriptor file (TLD) and is available only at translation time.

BODY_CONTENT_JSP

public static final String BODY_CONTENT_JSP

Static constant for getBodyContent() when it is JSP.

另请参见:

常量字段

BODY_CONTENT_TAG_DEPENDENT

public static final String BODY_CONTENT_TAG_DEPENDENT

Static constant for getBodyContent() when it is Tag dependent.

另请参见:

常量字段

BODY_CONTENT_EMPTY

public static final String BODY_CONTENT_EMPTY

Static constant for getBodyContent() when it is empty.

另请参见:

常量字段

BODY_CONTENT_SCRIPTLESS

public static final String BODY_CONTENT_SCRIPTLESS

Static constant for getBodyContent() when it is scriptless.

从以下版本开始:

JSP 2.0

另请参见:

常量字段

TagInfo

public TagInfo(String tagName,
               String tagClassName,
               String bodycontent,
               String infoString,
               TagLibraryInfo taglib,
               TagExtraInfo tagExtraInfo,
               TagAttributeInfo[] attributeInfo)

Constructor for TagInfo from data in the JSP 1.1 format for TLD. This class is to be instantiated only from the TagLibrary code under request from some JSP code that is parsing a TLD (Tag Library Descriptor). Note that, since TagLibibraryInfo reflects both TLD information and taglib directive information, a TagInfo instance is dependent on a taglib directive. This is probably a design error, which may be fixed in the future.

参数:

tagName - The name of this tag

tagClassName - The name of the tag handler class

bodycontent - Information on the body content of these tags

infoString - The (optional) string information for this tag

taglib - The instance of the tag library that contains us.

tagExtraInfo - The instance providing extra Tag info. May be null

attributeInfo - An array of AttributeInfo data from descriptor. May be null;

TagInfo

public TagInfo(String tagName,
               String tagClassName,
               String bodycontent,
               String infoString,
               TagLibraryInfo taglib,
               TagExtraInfo tagExtraInfo,
               TagAttributeInfo[] attributeInfo,
               String displayName,
               String smallIcon,
               String largeIcon,
               TagVariableInfo[] tvi)

Constructor for TagInfo from data in the JSP 1.2 format for TLD. This class is to be instantiated only from the TagLibrary code under request from some JSP code that is parsing a TLD (Tag Library Descriptor). Note that, since TagLibibraryInfo reflects both TLD information and taglib directive information, a TagInfo instance is dependent on a taglib directive. This is probably a design error, which may be fixed in the future.

参数:

tagName - The name of this tag

tagClassName - The name of the tag handler class

bodycontent - Information on the body content of these tags

infoString - The (optional) string information for this tag

taglib - The instance of the tag library that contains us.

tagExtraInfo - The instance providing extra Tag info. May be null

attributeInfo - An array of AttributeInfo data from descriptor. May be null;

displayName - A short name to be displayed by tools

smallIcon - Path to a small icon to be displayed by tools

largeIcon - Path to a large icon to be displayed by tools

tvi - An array of a TagVariableInfo (or null)

TagInfo

public TagInfo(String tagName,
               String tagClassName,
               String bodycontent,
               String infoString,
               TagLibraryInfo taglib,
               TagExtraInfo tagExtraInfo,
               TagAttributeInfo[] attributeInfo,
               String displayName,
               String smallIcon,
               String largeIcon,
               TagVariableInfo[] tvi,
               boolean dynamicAttributes)

Constructor for TagInfo from data in the JSP 2.0 format for TLD. This class is to be instantiated only from the TagLibrary code under request from some JSP code that is parsing a TLD (Tag Library Descriptor). Note that, since TagLibibraryInfo reflects both TLD information and taglib directive information, a TagInfo instance is dependent on a taglib directive. This is probably a design error, which may be fixed in the future.

参数:

tagName - The name of this tag

tagClassName - The name of the tag handler class

bodycontent - Information on the body content of these tags

infoString - The (optional) string information for this tag

taglib - The instance of the tag library that contains us.

tagExtraInfo - The instance providing extra Tag info. May be null

attributeInfo - An array of AttributeInfo data from descriptor. May be null;

displayName - A short name to be displayed by tools

smallIcon - Path to a small icon to be displayed by tools

largeIcon - Path to a large icon to be displayed by tools

tvi - An array of a TagVariableInfo (or null)

dynamicAttributes - True if supports dynamic attributes

从以下版本开始:

JSP 2.0

getTagName

public String getTagName()

The name of the Tag.

返回:

The (short) name of the tag.

getAttributes

public TagAttributeInfo[] getAttributes()

Attribute information (in the TLD) on this tag. The return is an array describing the attributes of this tag, as indicated in the TLD.

返回:

The array of TagAttributeInfo for this tag, or a zero-length array if the tag has no attributes.

getVariableInfo

public VariableInfo[] getVariableInfo(TagData data)

Information on the scripting objects created by this tag at runtime. This is a convenience method on the associated TagExtraInfo class.

参数:

data - TagData describing this action.

返回:

if a TagExtraInfo object is associated with this TagInfo, the result of getTagExtraInfo().getVariableInfo( data ), otherwise null.

isValid

public boolean isValid(TagData data)

Translation-time validation of the attributes. This is a convenience method on the associated TagExtraInfo class.

参数:

data - The translation-time TagData instance.

返回:

Whether the data is valid.

validate

public ValidationMessage[] validate(TagData data)

Translation-time validation of the attributes. This is a convenience method on the associated TagExtraInfo class.

参数:

data - The translation-time TagData instance.

返回:

A null object, or zero length array if no errors, an array of ValidationMessages otherwise.

从以下版本开始:

JSP 2.0

setTagExtraInfo

public void setTagExtraInfo(TagExtraInfo tei)

Set the instance for extra tag information.

参数:

tei - the TagExtraInfo instance

getTagExtraInfo

public TagExtraInfo getTagExtraInfo()

The instance (if any) for extra tag information.

返回:

The TagExtraInfo instance, if any.

getTagClassName

public String getTagClassName()

Name of the class that provides the handler for this tag.

返回:

The name of the tag handler class.

getBodyContent

public String getBodyContent()

The bodycontent information for this tag. If the bodycontent is not defined for this tag, the default of JSP will be returned.

返回:

the body content string.

getInfoString

public String getInfoString()

The information string for the tag.

返回:

the info string, or null if not defined

setTagLibrary

public void setTagLibrary(TagLibraryInfo tl)

Set the TagLibraryInfo property. Note that a TagLibraryInfo element is dependent not just on the TLD information but also on the specific taglib instance used. This means that a fair amount of work needs to be done to construct and initialize TagLib objects. If used carefully, this setter can be used to avoid having to create new TagInfo elements for each taglib directive.

参数:

tl - the TagLibraryInfo to assign

getTagLibrary

public TagLibraryInfo getTagLibrary()

The instance of TabLibraryInfo we belong to.

返回:

the tag library instance we belong to

getDisplayName

public String getDisplayName()

Get the displayName.

返回:

A short name to be displayed by tools, or null if not defined

getSmallIcon

public String getSmallIcon()

Get the path to the small icon.

返回:

Path to a small icon to be displayed by tools, or null if not defined

getLargeIcon

public String getLargeIcon()

Get the path to the large icon.

返回:

Path to a large icon to be displayed by tools, or null if not defined

getTagVariableInfos

public TagVariableInfo[] getTagVariableInfos()

Get TagVariableInfo objects associated with this TagInfo.

返回:

Array of TagVariableInfo objects corresponding to variables declared by this tag, or a zero length array if no variables have been declared

hasDynamicAttributes

public boolean hasDynamicAttributes()

Get dynamicAttributes associated with this TagInfo.

返回:

True if tag handler supports dynamic attributes

从以下版本开始:

JSP 2.0

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