TagAttributeInfo (Java EE 5)

Java EE API


javax.servlet.jsp.tagext Class TagAttributeInfo

java.lang.Object
  extended by javax.servlet.jsp.tagext.TagAttributeInfo

public class TagAttributeInfo
extends Object


有关 Tag 属性的信息,此类在转换期间可用。此类是根据标记库描述符文件 (TLD) 实例化的。

这里仅包含生成代码所需的信息。其他信息(比如用于验证的 SCHEMA)属于其他地方。

英文文档:

Information on the attributes of a Tag, available at translation time. This class is instantiated from the Tag Library Descriptor file (TLD).

Only the information needed to generate code is included here. Other information like SCHEMA for validation belongs elsewhere.

Note from the Expert Group:
This should have been designed as an interface. Every time we change the TLD, we need to add a new constructor to this class (not good). This class should only be instantiated by container implementations (not by JSP developers).


Field Summary
static String
 
Constructor Summary
 
Method Summary
 boolean
 String
 String
static TagAttributeInfo
 String
 String
 String
 boolean
 boolean
 boolean
 boolean
 String
 
Methods inherited from class java.lang.Object
 

Field Detail

英文文档:

ID

public static final String ID
"id" is wired in to be ID. There is no real benefit in having it be something else IDREFs are not handled any differently.

See Also:
Constant Field Values

Constructor Detail

public TagAttributeInfo(String name, boolean required, String type, boolean reqTime)
TagAttributeInfo 的构造方法。此类只能通过某些解析 TLD (Tag Library Descriptor) 的 JSP 代码所请求的 TagLibrary 代码进行实例化。
name 属性名称。
required 标记实例是否需要此属性。
type 属性类型的名称。
reqTime 此属性是否包含请求期间属性。
英文文档:

TagAttributeInfo

public TagAttributeInfo(String name,
                        boolean required,
                        String type,
                        boolean reqTime)
Constructor for TagAttributeInfo. 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).

Parameters:
name - The name of the attribute.
required - If this attribute is required in tag instances.
type - The name of the type of the attribute.
reqTime - Whether this attribute holds a request-time Attribute.


public TagAttributeInfo(String name, boolean required, String type, boolean reqTime, boolean fragment)
TagAttributeInfo 的 JSP 2.0 构造方法。此类只能通过某些解析 TLD (Tag Library Descriptor) 的 JSP 代码所请求的 TagLibrary 代码进行实例化。
name 属性名称。
required 标记实例是否需要此属性。
type 属性类型的名称。
reqTime 此属性是否包含请求期间属性。
fragment 此属性的类型是否为 JspFragment
since2.0
英文文档:

TagAttributeInfo

public TagAttributeInfo(String name,
                        boolean required,
                        String type,
                        boolean reqTime,
                        boolean fragment)
JSP 2.0 Constructor for TagAttributeInfo. 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).

Parameters:
name - The name of the attribute.
required - If this attribute is required in tag instances.
type - The name of the type of the attribute.
reqTime - Whether this attribute holds a request-time Attribute.
fragment - Whether this attribute is of type JspFragment
Since:
JSP 2.0


英文文档:

TagAttributeInfo

public TagAttributeInfo(String name,
                        boolean required,
                        String type,
                        boolean reqTime,
                        boolean fragment,
                        String description,
                        boolean deferredValue,
                        boolean deferredMethod,
                        String expectedTypeName,
                        String methodSignature)
JSP 2.1 Constructor for TagAttributeInfo. 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).

Parameters:
name - The name of the attribute.
required - If this attribute is required in tag instances.
type - The name of the type of the attribute.
reqTime - Whether this attribute holds a request-time Attribute.
fragment - Whether this attribute is of type JspFragment
description - The description of the attribute.
deferredValue - Whether this attribute is a deferred value.
deferredMethod - Whether this attribute is a deferred method. rtexpr or deferred value.
expectedTypeName - The name of the expected type of this deferred value (or null if this is not a deferred value).
methodSignature - The expected method signature of this deferred method (or null if this is not a deferred method).
Since:
JSP 2.1

Method Detail

public String getName()
此属性的名称。
return 属性的名称
英文文档:

getName

public String getName()
The name of this attribute.

Returns:
the name of the attribute

public String getTypeName()
此属性的类型(作为 String)。
return 属性的类型
英文文档:

getTypeName

public String getTypeName()
The type (as a String) of this attribute.

This method must return "javax.el.ValueExpression" if isDeferredValue() returns true and canBeRequestTime() returns false. It must return "javax.el.MethodExpression" if isDeferredMethod() returns true. It must return "java.lang.Object" if isDeferredValue() returns true and canBeRequestTime() returns true.

Returns:
the type of the attribute

public boolean canBeRequestTime()
此属性是否能包含请求期间值。
return 属性是否能包含请求期间值。
英文文档:

canBeRequestTime

public boolean canBeRequestTime()
Whether this attribute has been specified in the TLD as rtexprvalue. If true, this means the attribute can hold a request-time value.

Returns:
true if the attribute has been specified in the TLD as rtexprvalue

public boolean isRequired()
此属性是否是必需的。
return 属性是否是必需的。
英文文档:

isRequired

public boolean isRequired()
Whether this attribute is required.

Returns:
if the attribute is required.

public static TagAttributeInfo getIdAttribute(TagAttributeInfo[] a)
遍历 TagAttributeInfo 对象数组并查找 "id" 的便捷静态方法。
a TagAttributeInfo 数组
return 名称为 "id" 的 TagAttributeInfo 引用
英文文档:

getIdAttribute

public static TagAttributeInfo getIdAttribute(TagAttributeInfo[] a)
Convenience static method that goes through an array of TagAttributeInfo objects and looks for "id".

Parameters:
a - An array of TagAttributeInfo
Returns:
The TagAttributeInfo reference with name "id"

public boolean isFragment()
此属性的类型是否为 JspFragment。
return 属性的类型是否为 JspFragment
since2.0
英文文档:

isFragment

public boolean isFragment()
Whether this attribute is of type JspFragment.

Returns:
if the attribute is of type JspFragment
Since:
JSP 2.0

英文文档:

getDescription

public String getDescription()
Gets the description string of this tag attribute.

Returns:
the description string of this tag attribute

英文文档:

isDeferredValue

public boolean isDeferredValue()
Returns true if this attribute is to be passed a ValueExpression so that expression evaluation can be deferred.

If this method returns true, then getTypeName() must return "javax.el.ValueExpression".

The getExpectedType() method can be used to retrieve the expected type this value expression will be constructed with.

Returns:
true if this attribute accepts a deferred value; false otherwise.
Since:
JSP 2.1

英文文档:

isDeferredMethod

public boolean isDeferredMethod()
Returns true if this attribute is to be passed a MethodExpression so that expression evaluation can be deferred.

If this method returns true, then getTypeName() must return "javax.el.MethodExpression".

The getMethodSignature() method can be used to retrieve the expected method signature this method expression will be constructed with.

Returns:
true if this attribute accepts a deferred method; false otherwise.
Since:
JSP 2.1

英文文档:

getExpectedTypeName

public String getExpectedTypeName()
Returns the name of the expected type (as a String) of this deferred value attribute.

This method returns null if isDeferredValue() returns false.

Returns:
the name of the expected type
Since:
JSP 2.1

英文文档:

getMethodSignature

public String getMethodSignature()
Returns the expected method signature of this deferred method attribute.

This method returns null if isDeferredMethod() returns false.

Returns:
the method signature
Since:
JSP 2.1

public String toString()
返回此 TagAttributeInfo 的 String 表示形式,适用于调试目的。
return 此 TagAttributeInfo 的 String 表示形式
英文文档:

toString

public String toString()
Returns a String representation of this TagAttributeInfo, suitable for debugging purposes.

Overrides:
toString in class Object
Returns:
a String representation of this TagAttributeInfo


Submit a bug or feature

Copyright 2007 Sun Microsystems, Inc. All rights reserved. Use is subject to license terms.

一看就知道只有菜鸟才干这么无知的事啦。

PS : 未经我党受权你也可自由散发此文档。 如有任何错误请自行修正;若因此而造成任何损失请直接找人民主席,请勿与本人联系。谢谢!