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src/java.base/share/classes/java/util/Map.java
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@@ -32,53 +32,53 @@
/**
* An object that maps keys to values. A map cannot contain duplicate keys;
* each key can map to at most one value.
*
- * <p>This interface takes the place of the <tt>Dictionary</tt> class, which
+ * <p>This interface takes the place of the {@code Dictionary} class, which
* was a totally abstract class rather than an interface.
*
- * <p>The <tt>Map</tt> interface provides three <i>collection views</i>, which
+ * <p>The {@code Map} interface provides three <i>collection views</i>, which
* allow a map's contents to be viewed as a set of keys, collection of values,
* or set of key-value mappings. The <i>order</i> of a map is defined as
* the order in which the iterators on the map's collection views return their
- * elements. Some map implementations, like the <tt>TreeMap</tt> class, make
- * specific guarantees as to their order; others, like the <tt>HashMap</tt>
+ * elements. Some map implementations, like the {@code TreeMap} class, make
+ * specific guarantees as to their order; others, like the {@code HashMap}
* class, do not.
*
* <p>Note: great care must be exercised if mutable objects are used as map
* keys. The behavior of a map is not specified if the value of an object is
- * changed in a manner that affects <tt>equals</tt> comparisons while the
+ * changed in a manner that affects {@code equals} comparisons while the
* object is a key in the map. A special case of this prohibition is that it
* is not permissible for a map to contain itself as a key. While it is
* permissible for a map to contain itself as a value, extreme caution is
- * advised: the <tt>equals</tt> and <tt>hashCode</tt> methods are no longer
+ * advised: the {@code equals} and {@code hashCode} methods are no longer
* well defined on such a map.
*
* <p>All general-purpose map implementation classes should provide two
* "standard" constructors: a void (no arguments) constructor which creates an
- * empty map, and a constructor with a single argument of type <tt>Map</tt>,
+ * empty map, and a constructor with a single argument of type {@code Map},
* which creates a new map with the same key-value mappings as its argument.
* In effect, the latter constructor allows the user to copy any map,
* producing an equivalent map of the desired class. There is no way to
* enforce this recommendation (as interfaces cannot contain constructors) but
* all of the general-purpose map implementations in the JDK comply.
*
* <p>The "destructive" methods contained in this interface, that is, the
* methods that modify the map on which they operate, are specified to throw
- * <tt>UnsupportedOperationException</tt> if this map does not support the
+ * {@code UnsupportedOperationException} if this map does not support the
* operation. If this is the case, these methods may, but are not required
- * to, throw an <tt>UnsupportedOperationException</tt> if the invocation would
+ * to, throw an {@code UnsupportedOperationException} if the invocation would
* have no effect on the map. For example, invoking the {@link #putAll(Map)}
* method on an unmodifiable map may, but is not required to, throw the
* exception if the map whose mappings are to be "superimposed" is empty.
*
* <p>Some map implementations have restrictions on the keys and values they
* may contain. For example, some implementations prohibit null keys and
* values, and some have restrictions on the types of their keys. Attempting
* to insert an ineligible key or value throws an unchecked exception,
- * typically <tt>NullPointerException</tt> or <tt>ClassCastException</tt>.
+ * typically {@code NullPointerException} or {@code ClassCastException}.
* Attempting to query the presence of an ineligible key or value may throw an
* exception, or it may simply return false; some implementations will exhibit
* the former behavior and some will exhibit the latter. More generally,
* attempting an operation on an ineligible key or value whose completion
* would not result in the insertion of an ineligible element into the map may
@@ -87,17 +87,17 @@
* interface.
*
* <p>Many methods in Collections Framework interfaces are defined
* in terms of the {@link Object#equals(Object) equals} method. For
* example, the specification for the {@link #containsKey(Object)
- * containsKey(Object key)} method says: "returns <tt>true</tt> if and
- * only if this map contains a mapping for a key <tt>k</tt> such that
- * <tt>(key==null ? k==null : key.equals(k))</tt>." This specification should
- * <i>not</i> be construed to imply that invoking <tt>Map.containsKey</tt>
- * with a non-null argument <tt>key</tt> will cause <tt>key.equals(k)</tt> to
- * be invoked for any key <tt>k</tt>. Implementations are free to
- * implement optimizations whereby the <tt>equals</tt> invocation is avoided,
+ * containsKey(Object key)} method says: "returns {@code true} if and
+ * only if this map contains a mapping for a key {@code k} such that
+ * {@code (key==null ? k==null : key.equals(k))}." This specification should
+ * <i>not</i> be construed to imply that invoking {@code Map.containsKey}
+ * with a non-null argument {@code key} will cause {@code key.equals(k)} to
+ * be invoked for any key {@code k}. Implementations are free to
+ * implement optimizations whereby the {@code equals} invocation is avoided,
* for example, by first comparing the hash codes of the two keys. (The
* {@link Object#hashCode()} specification guarantees that two objects with
* unequal hash codes cannot be equal.) More generally, implementations of
* the various Collections Framework interfaces are free to take advantage of
* the specified behavior of underlying {@link Object} methods wherever the
@@ -129,33 +129,33 @@
public interface Map<K,V> {
// Query Operations
/**
* Returns the number of key-value mappings in this map. If the
- * map contains more than <tt>Integer.MAX_VALUE</tt> elements, returns
- * <tt>Integer.MAX_VALUE</tt>.
+ * map contains more than {@code Integer.MAX_VALUE} elements, returns
+ * {@code Integer.MAX_VALUE}.
*
* @return the number of key-value mappings in this map
*/
int size();
/**
- * Returns <tt>true</tt> if this map contains no key-value mappings.
+ * Returns {@code true} if this map contains no key-value mappings.
*
- * @return <tt>true</tt> if this map contains no key-value mappings
+ * @return {@code true} if this map contains no key-value mappings
*/
boolean isEmpty();
/**
- * Returns <tt>true</tt> if this map contains a mapping for the specified
- * key. More formally, returns <tt>true</tt> if and only if
- * this map contains a mapping for a key <tt>k</tt> such that
- * <tt>(key==null ? k==null : key.equals(k))</tt>. (There can be
+ * Returns {@code true} if this map contains a mapping for the specified
+ * key. More formally, returns {@code true} if and only if
+ * this map contains a mapping for a key {@code k} such that
+ * {@code (key==null ? k==null : key.equals(k))}. (There can be
* at most one such mapping.)
*
* @param key key whose presence in this map is to be tested
- * @return <tt>true</tt> if this map contains a mapping for the specified
+ * @return {@code true} if this map contains a mapping for the specified
* key
* @throws ClassCastException if the key is of an inappropriate type for
* this map
* (<a href="{@docRoot}/java/util/Collection.html#optional-restrictions">optional</a>)
* @throws NullPointerException if the specified key is null and this map
@@ -163,19 +163,19 @@
* (<a href="{@docRoot}/java/util/Collection.html#optional-restrictions">optional</a>)
*/
boolean containsKey(Object key);
/**
- * Returns <tt>true</tt> if this map maps one or more keys to the
- * specified value. More formally, returns <tt>true</tt> if and only if
- * this map contains at least one mapping to a value <tt>v</tt> such that
- * <tt>(value==null ? v==null : value.equals(v))</tt>. This operation
+ * Returns {@code true} if this map maps one or more keys to the
+ * specified value. More formally, returns {@code true} if and only if
+ * this map contains at least one mapping to a value {@code v} such that
+ * {@code (value==null ? v==null : value.equals(v))}. This operation
* will probably require time linear in the map size for most
- * implementations of the <tt>Map</tt> interface.
+ * implementations of the {@code Map} interface.
*
* @param value value whose presence in this map is to be tested
- * @return <tt>true</tt> if this map maps one or more keys to the
+ * @return {@code true} if this map maps one or more keys to the
* specified value
* @throws ClassCastException if the value is of an inappropriate type for
* this map
* (<a href="{@docRoot}/java/util/Collection.html#optional-restrictions">optional</a>)
* @throws NullPointerException if the specified value is null and this
@@ -215,22 +215,22 @@
/**
* Associates the specified value with the specified key in this map
* (optional operation). If the map previously contained a mapping for
* the key, the old value is replaced by the specified value. (A map
- * <tt>m</tt> is said to contain a mapping for a key <tt>k</tt> if and only
+ * {@code m} is said to contain a mapping for a key {@code k} if and only
* if {@link #containsKey(Object) m.containsKey(k)} would return
- * <tt>true</tt>.)
+ * {@code true}.)
*
* @param key key with which the specified value is to be associated
* @param value value to be associated with the specified key
- * @return the previous value associated with <tt>key</tt>, or
- * <tt>null</tt> if there was no mapping for <tt>key</tt>.
- * (A <tt>null</tt> return can also indicate that the map
- * previously associated <tt>null</tt> with <tt>key</tt>,
- * if the implementation supports <tt>null</tt> values.)
- * @throws UnsupportedOperationException if the <tt>put</tt> operation
+ * @return the previous value associated with {@code key}, or
+ * {@code null} if there was no mapping for {@code key}.
+ * (A {@code null} return can also indicate that the map
+ * previously associated {@code null} with {@code key},
+ * if the implementation supports {@code null} values.)
+ * @throws UnsupportedOperationException if the {@code put} operation
* is not supported by this map
* @throws ClassCastException if the class of the specified key or value
* prevents it from being stored in this map
* @throws NullPointerException if the specified key or value is null
* and this map does not permit null keys or values
@@ -240,29 +240,29 @@
V put(K key, V value);
/**
* Removes the mapping for a key from this map if it is present
* (optional operation). More formally, if this map contains a mapping
- * from key <tt>k</tt> to value <tt>v</tt> such that
- * <code>(key==null ? k==null : key.equals(k))</code>, that mapping
+ * from key {@code k} to value {@code v} such that
+ * {@code (key==null ? k==null : key.equals(k))}, that mapping
* is removed. (The map can contain at most one such mapping.)
*
* <p>Returns the value to which this map previously associated the key,
- * or <tt>null</tt> if the map contained no mapping for the key.
+ * or {@code null} if the map contained no mapping for the key.
*
* <p>If this map permits null values, then a return value of
- * <tt>null</tt> does not <i>necessarily</i> indicate that the map
+ * {@code null} does not <i>necessarily</i> indicate that the map
* contained no mapping for the key; it's also possible that the map
- * explicitly mapped the key to <tt>null</tt>.
+ * explicitly mapped the key to {@code null}.
*
* <p>The map will not contain a mapping for the specified key once the
* call returns.
*
* @param key key whose mapping is to be removed from the map
- * @return the previous value associated with <tt>key</tt>, or
- * <tt>null</tt> if there was no mapping for <tt>key</tt>.
- * @throws UnsupportedOperationException if the <tt>remove</tt> operation
+ * @return the previous value associated with {@code key}, or
+ * {@code null} if there was no mapping for {@code key}.
+ * @throws UnsupportedOperationException if the {@code remove} operation
* is not supported by this map
* @throws ClassCastException if the key is of an inappropriate type for
* this map
* (<a href="{@docRoot}/java/util/Collection.html#optional-restrictions">optional</a>)
* @throws NullPointerException if the specified key is null and this
@@ -276,16 +276,16 @@
/**
* Copies all of the mappings from the specified map to this map
* (optional operation). The effect of this call is equivalent to that
* of calling {@link #put(Object,Object) put(k, v)} on this map once
- * for each mapping from key <tt>k</tt> to value <tt>v</tt> in the
+ * for each mapping from key {@code k} to value {@code v} in the
* specified map. The behavior of this operation is undefined if the
* specified map is modified while the operation is in progress.
*
* @param m mappings to be stored in this map
- * @throws UnsupportedOperationException if the <tt>putAll</tt> operation
+ * @throws UnsupportedOperationException if the {@code putAll} operation
* is not supported by this map
* @throws ClassCastException if the class of a key or value in the
* specified map prevents it from being stored in this map
* @throws NullPointerException if the specified map is null, or if
* this map does not permit null keys or values, and the
@@ -297,11 +297,11 @@
/**
* Removes all of the mappings from this map (optional operation).
* The map will be empty after this call returns.
*
- * @throws UnsupportedOperationException if the <tt>clear</tt> operation
+ * @throws UnsupportedOperationException if the {@code clear} operation
* is not supported by this map
*/
void clear();
@@ -310,16 +310,16 @@
/**
* Returns a {@link Set} view of the keys contained in this map.
* The set is backed by the map, so changes to the map are
* reflected in the set, and vice-versa. If the map is modified
* while an iteration over the set is in progress (except through
- * the iterator's own <tt>remove</tt> operation), the results of
+ * the iterator's own {@code remove} operation), the results of
* the iteration are undefined. The set supports element removal,
* which removes the corresponding mapping from the map, via the
- * <tt>Iterator.remove</tt>, <tt>Set.remove</tt>,
- * <tt>removeAll</tt>, <tt>retainAll</tt>, and <tt>clear</tt>
- * operations. It does not support the <tt>add</tt> or <tt>addAll</tt>
+ * {@code Iterator.remove}, {@code Set.remove},
+ * {@code removeAll}, {@code retainAll}, and {@code clear}
+ * operations. It does not support the {@code add} or {@code addAll}
* operations.
*
* @return a set view of the keys contained in this map
*/
Set<K> keySet();
@@ -327,49 +327,49 @@
/**
* Returns a {@link Collection} view of the values contained in this map.
* The collection is backed by the map, so changes to the map are
* reflected in the collection, and vice-versa. If the map is
* modified while an iteration over the collection is in progress
- * (except through the iterator's own <tt>remove</tt> operation),
+ * (except through the iterator's own {@code remove} operation),
* the results of the iteration are undefined. The collection
* supports element removal, which removes the corresponding
- * mapping from the map, via the <tt>Iterator.remove</tt>,
- * <tt>Collection.remove</tt>, <tt>removeAll</tt>,
- * <tt>retainAll</tt> and <tt>clear</tt> operations. It does not
- * support the <tt>add</tt> or <tt>addAll</tt> operations.
+ * mapping from the map, via the {@code Iterator.remove},
+ * {@code Collection.remove}, {@code removeAll},
+ * {@code retainAll} and {@code clear} operations. It does not
+ * support the {@code add} or {@code addAll} operations.
*
* @return a collection view of the values contained in this map
*/
Collection<V> values();
/**
* Returns a {@link Set} view of the mappings contained in this map.
* The set is backed by the map, so changes to the map are
* reflected in the set, and vice-versa. If the map is modified
* while an iteration over the set is in progress (except through
- * the iterator's own <tt>remove</tt> operation, or through the
- * <tt>setValue</tt> operation on a map entry returned by the
+ * the iterator's own {@code remove} operation, or through the
+ * {@code setValue} operation on a map entry returned by the
* iterator) the results of the iteration are undefined. The set
* supports element removal, which removes the corresponding
- * mapping from the map, via the <tt>Iterator.remove</tt>,
- * <tt>Set.remove</tt>, <tt>removeAll</tt>, <tt>retainAll</tt> and
- * <tt>clear</tt> operations. It does not support the
- * <tt>add</tt> or <tt>addAll</tt> operations.
+ * mapping from the map, via the {@code Iterator.remove},
+ * {@code Set.remove}, {@code removeAll}, {@code retainAll} and
+ * {@code clear} operations. It does not support the
+ * {@code add} or {@code addAll} operations.
*
* @return a set view of the mappings contained in this map
*/
Set<Map.Entry<K, V>> entrySet();
/**
- * A map entry (key-value pair). The <tt>Map.entrySet</tt> method returns
+ * A map entry (key-value pair). The {@code Map.entrySet} method returns
* a collection-view of the map, whose elements are of this class. The
* <i>only</i> way to obtain a reference to a map entry is from the
- * iterator of this collection-view. These <tt>Map.Entry</tt> objects are
+ * iterator of this collection-view. These {@code Map.Entry} objects are
* valid <i>only</i> for the duration of the iteration; more formally,
* the behavior of a map entry is undefined if the backing map has been
* modified after the entry was returned by the iterator, except through
- * the <tt>setValue</tt> operation on the map entry.
+ * the {@code setValue} operation on the map entry.
*
* @see Map#entrySet()
* @since 1.2
*/
interface Entry<K,V> {
@@ -384,11 +384,11 @@
K getKey();
/**
* Returns the value corresponding to this entry. If the mapping
* has been removed from the backing map (by the iterator's
- * <tt>remove</tt> operation), the results of this call are undefined.
+ * {@code remove} operation), the results of this call are undefined.
*
* @return the value corresponding to this entry
* @throws IllegalStateException implementations may, but are not
* required to, throw this exception if the entry has been
* removed from the backing map.
@@ -397,15 +397,15 @@
/**
* Replaces the value corresponding to this entry with the specified
* value (optional operation). (Writes through to the map.) The
* behavior of this call is undefined if the mapping has already been
- * removed from the map (by the iterator's <tt>remove</tt> operation).
+ * removed from the map (by the iterator's {@code remove} operation).
*
* @param value new value to be stored in this entry
* @return old value corresponding to the entry
- * @throws UnsupportedOperationException if the <tt>put</tt> operation
+ * @throws UnsupportedOperationException if the {@code put} operation
* is not supported by the backing map
* @throws ClassCastException if the class of the specified value
* prevents it from being stored in the backing map
* @throws NullPointerException if the backing map does not permit
* null values, and the specified value is null
@@ -417,38 +417,38 @@
*/
V setValue(V value);
/**
* Compares the specified object with this entry for equality.
- * Returns <tt>true</tt> if the given object is also a map entry and
+ * Returns {@code true} if the given object is also a map entry and
* the two entries represent the same mapping. More formally, two
- * entries <tt>e1</tt> and <tt>e2</tt> represent the same mapping
+ * entries {@code e1} and {@code e2} represent the same mapping
* if<pre>
* (e1.getKey()==null ?
* e2.getKey()==null : e1.getKey().equals(e2.getKey())) &&
* (e1.getValue()==null ?
* e2.getValue()==null : e1.getValue().equals(e2.getValue()))
* </pre>
- * This ensures that the <tt>equals</tt> method works properly across
- * different implementations of the <tt>Map.Entry</tt> interface.
+ * This ensures that the {@code equals} method works properly across
+ * different implementations of the {@code Map.Entry} interface.
*
* @param o object to be compared for equality with this map entry
- * @return <tt>true</tt> if the specified object is equal to this map
+ * @return {@code true} if the specified object is equal to this map
* entry
*/
boolean equals(Object o);
/**
* Returns the hash code value for this map entry. The hash code
- * of a map entry <tt>e</tt> is defined to be: <pre>
+ * of a map entry {@code e} is defined to be: <pre>
* (e.getKey()==null ? 0 : e.getKey().hashCode()) ^
* (e.getValue()==null ? 0 : e.getValue().hashCode())
* </pre>
- * This ensures that <tt>e1.equals(e2)</tt> implies that
- * <tt>e1.hashCode()==e2.hashCode()</tt> for any two Entries
- * <tt>e1</tt> and <tt>e2</tt>, as required by the general
- * contract of <tt>Object.hashCode</tt>.
+ * This ensures that {@code e1.equals(e2)} implies that
+ * {@code e1.hashCode()==e2.hashCode()} for any two Entries
+ * {@code e1} and {@code e2}, as required by the general
+ * contract of {@code Object.hashCode}.
*
* @return the hash code value for this map entry
* @see Object#hashCode()
* @see Object#equals(Object)
* @see #equals(Object)
@@ -530,28 +530,28 @@
// Comparison and hashing
/**
* Compares the specified object with this map for equality. Returns
- * <tt>true</tt> if the given object is also a map and the two maps
- * represent the same mappings. More formally, two maps <tt>m1</tt> and
- * <tt>m2</tt> represent the same mappings if
- * <tt>m1.entrySet().equals(m2.entrySet())</tt>. This ensures that the
- * <tt>equals</tt> method works properly across different implementations
- * of the <tt>Map</tt> interface.
+ * {@code true} if the given object is also a map and the two maps
+ * represent the same mappings. More formally, two maps {@code m1} and
+ * {@code m2} represent the same mappings if
+ * {@code m1.entrySet().equals(m2.entrySet())}. This ensures that the
+ * {@code equals} method works properly across different implementations
+ * of the {@code Map} interface.
*
* @param o object to be compared for equality with this map
- * @return <tt>true</tt> if the specified object is equal to this map
+ * @return {@code true} if the specified object is equal to this map
*/
boolean equals(Object o);
/**
* Returns the hash code value for this map. The hash code of a map is
* defined to be the sum of the hash codes of each entry in the map's
- * <tt>entrySet()</tt> view. This ensures that <tt>m1.equals(m2)</tt>
- * implies that <tt>m1.hashCode()==m2.hashCode()</tt> for any two maps
- * <tt>m1</tt> and <tt>m2</tt>, as required by the general contract of
+ * {@code entrySet()} view. This ensures that {@code m1.equals(m2)}
+ * implies that {@code m1.hashCode()==m2.hashCode()} for any two maps
+ * {@code m1} and {@code m2}, as required by the general contract of
* {@link Object#hashCode}.
*
* @return the hash code value for this map
* @see Map.Entry#hashCode()
* @see Object#equals(Object)
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