程序包 java.util.jar

类 Attributes

java.lang.Object

java.util.jar.Attributes

所有已实现的接口:

Cloneable, Map<Object,Object>

public class Attributes
extends Object
implements Map<Object,Object>, Cloneable

The Attributes class maps Manifest attribute names to associated string values. Valid attribute names are case-insensitive, are restricted to the ASCII characters in the set [0-9a-zA-Z_-], and cannot exceed 70 characters in length. Attribute values can contain any characters and will be UTF8-encoded when written to the output stream. See the JAR File Specification for more information about valid attribute names and values.

从以下版本开始:

1.2

另请参阅:

Manifest

嵌套类概要

嵌套类

限定符和类型	类	说明
static class	Attributes.Name	The Attributes.Name class represents an attribute name stored in this Map.

从接口继承的嵌套类/接口 java.util.Map

Map.Entry<K,V>

字段概要

字段

限定符和类型	字段	说明
protected Map<Object,Object>	map	The attribute name-value mappings.

构造器概要

构造器

构造器	说明
Attributes()	Constructs a new, empty Attributes object with default size.
Attributes(int size)	Constructs a new, empty Attributes object with the specified initial size.
Attributes(Attributes attr)	Constructs a new Attributes object with the same attribute name-value mappings as in the specified Attributes.

方法概要

限定符和类型	方法	说明
void	clear()	Removes all attributes from this Map.
Object	clone()	Returns a copy of the Attributes, implemented as follows:
boolean	containsKey(Object name)	Returns true if this Map contains the specified attribute name (key).
boolean	containsValue(Object value)	Returns true if this Map maps one or more attribute names (keys) to the specified value.
Set<Map.Entry<Object,Object>>	entrySet()	Returns a Collection view of the attribute name-value mappings contained in this Map.
boolean	equals(Object o)	Compares the specified Attributes object with this Map for equality.
Object	get(Object name)	Returns the value of the specified attribute name, or null if the attribute name was not found.
String	getValue(String name)	Returns the value of the specified attribute name, specified as a string, or null if the attribute was not found.
String	getValue(Attributes.Name name)	Returns the value of the specified Attributes.Name, or null if the attribute was not found.
int	hashCode()	Returns the hash code value for this Map.
boolean	isEmpty()	Returns true if this Map contains no attributes.
Set<Object>	keySet()	Returns a Set view of the attribute names (keys) contained in this Map.
Object	put(Object name, Object value)	Associates the specified value with the specified attribute name (key) in this Map.
void	putAll(Map<?,?> attr)	Copies all of the attribute name-value mappings from the specified Attributes to this Map.
String	putValue(String name, String value)	Associates the specified value with the specified attribute name, specified as a String.
Object	remove(Object name)	Removes the attribute with the specified name (key) from this Map.
int	size()	Returns the number of attributes in this Map.
Collection<Object>	values()	Returns a Collection view of the attribute values contained in this Map.

从接口继承的方法 java.util.Map

compute, computeIfAbsent, computeIfPresent, forEach, getOrDefault, merge, putIfAbsent, remove, replace, replace, replaceAll

从类继承的方法 java.lang.Object

finalize, getClass, notify, notifyAll, toString, wait, wait, wait

字段详细资料

map

protected Map<Object,Object> map

The attribute name-value mappings.

构造器详细资料

Attributes

public Attributes()

Constructs a new, empty Attributes object with default size.

Attributes

public Attributes(int size)

Constructs a new, empty Attributes object with the specified initial size.

参数:

size - the initial number of attributes

Attributes

public Attributes(Attributes attr)

Constructs a new Attributes object with the same attribute name-value mappings as in the specified Attributes.

参数:

attr - the specified Attributes

方法详细资料

get

public Object get(Object name)

Returns the value of the specified attribute name, or null if the attribute name was not found.

指定者:

get 在接口中 Map<Object,Object>

参数:

name - the attribute name

返回:

the value of the specified attribute name, or null if not found.

getValue

public String getValue(String name)

Returns the value of the specified attribute name, specified as a string, or null if the attribute was not found. The attribute name is case-insensitive.

This method is defined as:

      return (String)get(new Attributes.Name((String)name));
 

参数:

name - the attribute name as a string

返回:

the String value of the specified attribute name, or null if not found.

抛出:

IllegalArgumentException - if the attribute name is invalid

getValue

public String getValue(Attributes.Name name)

Returns the value of the specified Attributes.Name, or null if the attribute was not found.

This method is defined as:

     return (String)get(name);
 

参数:

name - the Attributes.Name object

返回:

the String value of the specified Attribute.Name, or null if not found.

put

public Object put(Object name,
                  Object value)

Associates the specified value with the specified attribute name (key) in this Map. If the Map previously contained a mapping for the attribute name, the old value is replaced.

指定者:

put 在接口中 Map<Object,Object>

参数:

name - the attribute name

value - the attribute value

返回:

the previous value of the attribute, or null if none

抛出:

ClassCastException - if the name is not a Attributes.Name or the value is not a String

putValue

public String putValue(String name,
                       String value)

Associates the specified value with the specified attribute name, specified as a String. The attributes name is case-insensitive. If the Map previously contained a mapping for the attribute name, the old value is replaced.

This method is defined as:

      return (String)put(new Attributes.Name(name), value);
 

参数:

name - the attribute name as a string

value - the attribute value

返回:

the previous value of the attribute, or null if none

抛出:

IllegalArgumentException - if the attribute name is invalid

remove

public Object remove(Object name)

Removes the attribute with the specified name (key) from this Map. Returns the previous attribute value, or null if none.

指定者:

remove 在接口中 Map<Object,Object>

参数:

name - attribute name

返回:

the previous value of the attribute, or null if none

containsValue

public boolean containsValue(Object value)

Returns true if this Map maps one or more attribute names (keys) to the specified value.

指定者:

containsValue 在接口中 Map<Object,Object>

参数:

value - the attribute value

返回:

true if this Map maps one or more attribute names to the specified value

containsKey

public boolean containsKey(Object name)

Returns true if this Map contains the specified attribute name (key).

指定者:

containsKey 在接口中 Map<Object,Object>

参数:

name - the attribute name

返回:

true if this Map contains the specified attribute name

putAll

public void putAll(Map<?,?> attr)

Copies all of the attribute name-value mappings from the specified Attributes to this Map. Duplicate mappings will be replaced.

指定者:

putAll 在接口中 Map<Object,Object>

参数:

attr - the Attributes to be stored in this map

抛出:

ClassCastException - if attr is not an Attributes

clear

public void clear()

Removes all attributes from this Map.

指定者:

clear 在接口中 Map<Object,Object>

size

public int size()

Returns the number of attributes in this Map.

指定者:

size 在接口中 Map<Object,Object>

返回:

the number of key-value mappings in this map

isEmpty

public boolean isEmpty()

Returns true if this Map contains no attributes.

指定者:

isEmpty 在接口中 Map<Object,Object>

返回:

true if this map contains no key-value mappings

keySet

public Set<Object> keySet()

Returns a Set view of the attribute names (keys) contained in this Map.

指定者:

keySet 在接口中 Map<Object,Object>

返回:

a set view of the keys contained in this map

values

public Collection<Object> values()

Returns a Collection view of the attribute values contained in this Map.

指定者:

values 在接口中 Map<Object,Object>

返回:

a collection view of the values contained in this map

entrySet

public Set<Map.Entry<Object,Object>> entrySet()

Returns a Collection view of the attribute name-value mappings contained in this Map.

指定者:

entrySet 在接口中 Map<Object,Object>

返回:

a set view of the mappings contained in this map

equals

public boolean equals(Object o)

Compares the specified Attributes object with this Map for equality. Returns true if the given object is also an instance of Attributes and the two Attributes objects represent the same mappings.

指定者:

equals 在接口中 Map<Object,Object>

覆盖:

equals 在类中 Object

参数:

o - the Object to be compared

返回:

true if the specified Object is equal to this Map

另请参阅:

Object.hashCode(), HashMap

hashCode

public int hashCode()

Returns the hash code value for this Map.

指定者:

hashCode 在接口中 Map<Object,Object>

覆盖:

hashCode 在类中 Object

返回:

a hash code value for this object.

另请参阅:

Object.equals(java.lang.Object), System.identityHashCode(java.lang.Object)

clone

public Object clone()

Returns a copy of the Attributes, implemented as follows:

     public Object clone() { return new Attributes(this); }
 

Since the attribute names and values are themselves immutable, the Attributes returned can be safely modified without affecting the original.

覆盖:

clone 在类中 Object

返回:

a clone of this instance.

另请参阅:

Cloneable