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src/java.base/share/classes/java/util/Dictionary.java
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*** 24,41 ****
*/
package java.util;
/**
! * The <code>Dictionary</code> class is the abstract parent of any
! * class, such as <code>Hashtable</code>, which maps keys to values.
! * Every key and every value is an object. In any one <tt>Dictionary</tt>
* object, every key is associated with at most one value. Given a
! * <tt>Dictionary</tt> and a key, the associated element can be looked up.
! * Any non-<code>null</code> object can be used as a key and as a value.
* <p>
! * As a rule, the <code>equals</code> method should be used by
* implementations of this class to decide if two keys are the same.
* <p>
* <strong>NOTE: This class is obsolete. New implementations should
* implement the Map interface, rather than extending this class.</strong>
*
--- 24,41 ----
*/
package java.util;
/**
! * The {@code Dictionary} class is the abstract parent of any
! * class, such as {@code Hashtable}, which maps keys to values.
! * Every key and every value is an object. In any one {@code Dictionary}
* object, every key is associated with at most one value. Given a
! * {@code Dictionary} and a key, the associated element can be looked up.
! * Any non-{@code null} object can be used as a key and as a value.
* <p>
! * As a rule, the {@code equals} method should be used by
* implementations of this class to decide if two keys are the same.
* <p>
* <strong>NOTE: This class is obsolete. New implementations should
* implement the Map interface, rather than extending this class.</strong>
*
*** 62,82 ****
*/
abstract public int size();
/**
* Tests if this dictionary maps no keys to value. The general contract
! * for the <tt>isEmpty</tt> method is that the result is true if and only
* if this dictionary contains no entries.
*
! * @return <code>true</code> if this dictionary maps no keys to values;
! * <code>false</code> otherwise.
*/
abstract public boolean isEmpty();
/**
* Returns an enumeration of the keys in this dictionary. The general
! * contract for the keys method is that an <tt>Enumeration</tt> object
* is returned that will generate all the keys for which this dictionary
* contains entries.
*
* @return an enumeration of the keys in this dictionary.
* @see java.util.Dictionary#elements()
--- 62,82 ----
*/
abstract public int size();
/**
* Tests if this dictionary maps no keys to value. The general contract
! * for the {@code isEmpty} method is that the result is true if and only
* if this dictionary contains no entries.
*
! * @return {@code true} if this dictionary maps no keys to values;
! * {@code false} otherwise.
*/
abstract public boolean isEmpty();
/**
* Returns an enumeration of the keys in this dictionary. The general
! * contract for the keys method is that an {@code Enumeration} object
* is returned that will generate all the keys for which this dictionary
* contains entries.
*
* @return an enumeration of the keys in this dictionary.
* @see java.util.Dictionary#elements()
*** 84,155 ****
*/
abstract public Enumeration<K> keys();
/**
* Returns an enumeration of the values in this dictionary. The general
! * contract for the <tt>elements</tt> method is that an
! * <tt>Enumeration</tt> is returned that will generate all the elements
* contained in entries in this dictionary.
*
* @return an enumeration of the values in this dictionary.
* @see java.util.Dictionary#keys()
* @see java.util.Enumeration
*/
abstract public Enumeration<V> elements();
/**
* Returns the value to which the key is mapped in this dictionary.
! * The general contract for the <tt>isEmpty</tt> method is that if this
* dictionary contains an entry for the specified key, the associated
! * value is returned; otherwise, <tt>null</tt> is returned.
*
* @return the value to which the key is mapped in this dictionary;
* @param key a key in this dictionary.
! * <code>null</code> if the key is not mapped to any value in
* this dictionary.
! * @exception NullPointerException if the <tt>key</tt> is <tt>null</tt>.
* @see java.util.Dictionary#put(java.lang.Object, java.lang.Object)
*/
abstract public V get(Object key);
/**
! * Maps the specified <code>key</code> to the specified
! * <code>value</code> in this dictionary. Neither the key nor the
! * value can be <code>null</code>.
* <p>
* If this dictionary already contains an entry for the specified
! * <tt>key</tt>, the value already in this dictionary for that
! * <tt>key</tt> is returned, after modifying the entry to contain the
* new element. <p>If this dictionary does not already have an entry
! * for the specified <tt>key</tt>, an entry is created for the
! * specified <tt>key</tt> and <tt>value</tt>, and <tt>null</tt> is
* returned.
* <p>
! * The <code>value</code> can be retrieved by calling the
! * <code>get</code> method with a <code>key</code> that is equal to
! * the original <code>key</code>.
*
* @param key the hashtable key.
* @param value the value.
! * @return the previous value to which the <code>key</code> was mapped
! * in this dictionary, or <code>null</code> if the key did not
* have a previous mapping.
! * @exception NullPointerException if the <code>key</code> or
! * <code>value</code> is <code>null</code>.
* @see java.lang.Object#equals(java.lang.Object)
* @see java.util.Dictionary#get(java.lang.Object)
*/
abstract public V put(K key, V value);
/**
! * Removes the <code>key</code> (and its corresponding
! * <code>value</code>) from this dictionary. This method does nothing
! * if the <code>key</code> is not in this dictionary.
*
* @param key the key that needs to be removed.
! * @return the value to which the <code>key</code> had been mapped in this
! * dictionary, or <code>null</code> if the key did not have a
* mapping.
! * @exception NullPointerException if <tt>key</tt> is <tt>null</tt>.
*/
abstract public V remove(Object key);
}
--- 84,155 ----
*/
abstract public Enumeration<K> keys();
/**
* Returns an enumeration of the values in this dictionary. The general
! * contract for the {@code elements} method is that an
! * {@code Enumeration} is returned that will generate all the elements
* contained in entries in this dictionary.
*
* @return an enumeration of the values in this dictionary.
* @see java.util.Dictionary#keys()
* @see java.util.Enumeration
*/
abstract public Enumeration<V> elements();
/**
* Returns the value to which the key is mapped in this dictionary.
! * The general contract for the {@code isEmpty} method is that if this
* dictionary contains an entry for the specified key, the associated
! * value is returned; otherwise, {@code null} is returned.
*
* @return the value to which the key is mapped in this dictionary;
* @param key a key in this dictionary.
! * {@code null} if the key is not mapped to any value in
* this dictionary.
! * @exception NullPointerException if the {@code key} is {@code null}.
* @see java.util.Dictionary#put(java.lang.Object, java.lang.Object)
*/
abstract public V get(Object key);
/**
! * Maps the specified {@code key} to the specified
! * {@code value} in this dictionary. Neither the key nor the
! * value can be {@code null}.
* <p>
* If this dictionary already contains an entry for the specified
! * {@code key}, the value already in this dictionary for that
! * {@code key} is returned, after modifying the entry to contain the
* new element. <p>If this dictionary does not already have an entry
! * for the specified {@code key}, an entry is created for the
! * specified {@code key} and {@code value}, and {@code null} is
* returned.
* <p>
! * The {@code value} can be retrieved by calling the
! * {@code get} method with a {@code key} that is equal to
! * the original {@code key}.
*
* @param key the hashtable key.
* @param value the value.
! * @return the previous value to which the {@code key} was mapped
! * in this dictionary, or {@code null} if the key did not
* have a previous mapping.
! * @exception NullPointerException if the {@code key} or
! * {@code value} is {@code null}.
* @see java.lang.Object#equals(java.lang.Object)
* @see java.util.Dictionary#get(java.lang.Object)
*/
abstract public V put(K key, V value);
/**
! * Removes the {@code key} (and its corresponding
! * {@code value}) from this dictionary. This method does nothing
! * if the {@code key} is not in this dictionary.
*
* @param key the key that needs to be removed.
! * @return the value to which the {@code key} had been mapped in this
! * dictionary, or {@code null} if the key did not have a
* mapping.
! * @exception NullPointerException if {@code key} is {@code null}.
*/
abstract public V remove(Object key);
}
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