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src/java.base/share/classes/java/util/Collection.java
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@@ -33,45 +33,45 @@
* The root interface in the <i>collection hierarchy</i>. A collection
* represents a group of objects, known as its <i>elements</i>. Some
* collections allow duplicate elements and others do not. Some are ordered
* and others unordered. The JDK does not provide any <i>direct</i>
* implementations of this interface: it provides implementations of more
- * specific subinterfaces like <tt>Set</tt> and <tt>List</tt>. This interface
+ * specific subinterfaces like {@code Set} and {@code List}. This interface
* is typically used to pass collections around and manipulate them where
* maximum generality is desired.
*
* <p><i>Bags</i> or <i>multisets</i> (unordered collections that may contain
* duplicate elements) should implement this interface directly.
*
- * <p>All general-purpose <tt>Collection</tt> implementation classes (which
- * typically implement <tt>Collection</tt> indirectly through one of its
+ * <p>All general-purpose {@code Collection} implementation classes (which
+ * typically implement {@code Collection} indirectly through one of its
* subinterfaces) should provide two "standard" constructors: a void (no
* arguments) constructor, which creates an empty collection, and a
- * constructor with a single argument of type <tt>Collection</tt>, which
+ * constructor with a single argument of type {@code Collection}, which
* creates a new collection with the same elements as its argument. In
* effect, the latter constructor allows the user to copy any collection,
* producing an equivalent collection of the desired implementation type.
* There is no way to enforce this convention (as interfaces cannot contain
- * constructors) but all of the general-purpose <tt>Collection</tt>
+ * constructors) but all of the general-purpose {@code Collection}
* implementations in the Java platform libraries comply.
*
* <p>The "destructive" methods contained in this interface, that is, the
* methods that modify the collection on which they operate, are specified to
- * throw <tt>UnsupportedOperationException</tt> if this collection does not
+ * throw {@code UnsupportedOperationException} if this collection 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
+ * required to, throw an {@code UnsupportedOperationException} if the
* invocation would have no effect on the collection. For example, invoking
* the {@link #addAll(Collection)} method on an unmodifiable collection may,
* but is not required to, throw the exception if the collection to be added
* is empty.
*
* <p><a name="optional-restrictions">
* Some collection implementations have restrictions on the elements that
* they may contain.</a> For example, some implementations prohibit null elements,
* and some have restrictions on the types of their elements. Attempting to
* add an ineligible element throws an unchecked exception, typically
- * <tt>NullPointerException</tt> or <tt>ClassCastException</tt>. Attempting
+ * {@code NullPointerException} or {@code ClassCastException}. Attempting
* to query the presence of an ineligible element 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 element whose completion would not result in
* the insertion of an ineligible element into the collection may throw an
@@ -88,17 +88,17 @@
* iterator to examine the collection.
*
* <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 #contains(Object) contains(Object o)}
- * method says: "returns <tt>true</tt> if and only if this collection
- * contains at least one element <tt>e</tt> such that
- * <tt>(o==null ? e==null : o.equals(e))</tt>." This specification should
- * <i>not</i> be construed to imply that invoking <tt>Collection.contains</tt>
- * with a non-null argument <tt>o</tt> will cause <tt>o.equals(e)</tt> to be
- * invoked for any element <tt>e</tt>. Implementations are free to implement
- * optimizations whereby the <tt>equals</tt> invocation is avoided, for
+ * method says: "returns {@code true} if and only if this collection
+ * contains at least one element {@code e} such that
+ * {@code (o==null ? e==null : o.equals(e))}." This specification should
+ * <i>not</i> be construed to imply that invoking {@code Collection.contains}
+ * with a non-null argument {@code o} will cause {@code o.equals(e)} to be
+ * invoked for any element {@code e}. Implementations are free to implement
+ * optimizations whereby the {@code equals} invocation is avoided, for
* example, by first comparing the hash codes of the two elements. (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
@@ -144,32 +144,32 @@
public interface Collection<E> extends Iterable<E> {
// Query Operations
/**
* Returns the number of elements in this collection. If this collection
- * contains more than <tt>Integer.MAX_VALUE</tt> elements, returns
- * <tt>Integer.MAX_VALUE</tt>.
+ * contains more than {@code Integer.MAX_VALUE} elements, returns
+ * {@code Integer.MAX_VALUE}.
*
* @return the number of elements in this collection
*/
int size();
/**
- * Returns <tt>true</tt> if this collection contains no elements.
+ * Returns {@code true} if this collection contains no elements.
*
- * @return <tt>true</tt> if this collection contains no elements
+ * @return {@code true} if this collection contains no elements
*/
boolean isEmpty();
/**
- * Returns <tt>true</tt> if this collection contains the specified element.
- * More formally, returns <tt>true</tt> if and only if this collection
- * contains at least one element <tt>e</tt> such that
- * <tt>(o==null ? e==null : o.equals(e))</tt>.
+ * Returns {@code true} if this collection contains the specified element.
+ * More formally, returns {@code true} if and only if this collection
+ * contains at least one element {@code e} such that
+ * <code>(o==null ? e==null : o.equals(e))</code>.
*
* @param o element whose presence in this collection is to be tested
- * @return <tt>true</tt> if this collection contains the specified
+ * @return {@code true} if this collection contains the specified
* element
* @throws ClassCastException if the type of the specified element
* is incompatible with this collection
* (<a href="#optional-restrictions">optional</a>)
* @throws NullPointerException if the specified element is null and this
@@ -182,11 +182,11 @@
* Returns an iterator over the elements in this collection. There are no
* guarantees concerning the order in which the elements are returned
* (unless this collection is an instance of some class that provides a
* guarantee).
*
- * @return an <tt>Iterator</tt> over the elements in this collection
+ * @return an {@code Iterator} over the elements in this collection
*/
Iterator<E> iterator();
/**
* Returns an array containing all of the elements in this collection.
@@ -214,32 +214,32 @@
* specified array and the size of this collection.
*
* <p>If this collection fits in the specified array with room to spare
* (i.e., the array has more elements than this collection), the element
* in the array immediately following the end of the collection is set to
- * <tt>null</tt>. (This is useful in determining the length of this
+ * {@code null}. (This is useful in determining the length of this
* collection <i>only</i> if the caller knows that this collection does
- * not contain any <tt>null</tt> elements.)
+ * not contain any {@code null} elements.)
*
* <p>If this collection makes any guarantees as to what order its elements
* are returned by its iterator, this method must return the elements in
* the same order.
*
* <p>Like the {@link #toArray()} method, this method acts as bridge between
* array-based and collection-based APIs. Further, this method allows
* precise control over the runtime type of the output array, and may,
* under certain circumstances, be used to save allocation costs.
*
- * <p>Suppose <tt>x</tt> is a collection known to contain only strings.
+ * <p>Suppose {@code x} is a collection known to contain only strings.
* The following code can be used to dump the collection into a newly
- * allocated array of <tt>String</tt>:
+ * allocated array of {@code String}:
*
* <pre>
* String[] y = x.toArray(new String[0]);</pre>
*
- * Note that <tt>toArray(new Object[0])</tt> is identical in function to
- * <tt>toArray()</tt>.
+ * Note that {@code toArray(new Object[0])} is identical in function to
+ * {@code toArray()}.
*
* @param <T> the runtime type of the array to contain the collection
* @param a the array into which the elements of this collection are to be
* stored, if it is big enough; otherwise, a new array of the same
* runtime type is allocated for this purpose.
@@ -253,31 +253,31 @@
// Modification Operations
/**
* Ensures that this collection contains the specified element (optional
- * operation). Returns <tt>true</tt> if this collection changed as a
- * result of the call. (Returns <tt>false</tt> if this collection does
+ * operation). Returns {@code true} if this collection changed as a
+ * result of the call. (Returns {@code false} if this collection does
* not permit duplicates and already contains the specified element.)<p>
*
* Collections that support this operation may place limitations on what
* elements may be added to this collection. In particular, some
- * collections will refuse to add <tt>null</tt> elements, and others will
+ * collections will refuse to add {@code null} elements, and others will
* impose restrictions on the type of elements that may be added.
* Collection classes should clearly specify in their documentation any
* restrictions on what elements may be added.<p>
*
* If a collection refuses to add a particular element for any reason
* other than that it already contains the element, it <i>must</i> throw
- * an exception (rather than returning <tt>false</tt>). This preserves
+ * an exception (rather than returning {@code false}). This preserves
* the invariant that a collection always contains the specified element
* after this call returns.
*
* @param e element whose presence in this collection is to be ensured
- * @return <tt>true</tt> if this collection changed as a result of the
+ * @return {@code true} if this collection changed as a result of the
* call
- * @throws UnsupportedOperationException if the <tt>add</tt> operation
+ * @throws UnsupportedOperationException if the {@code add} operation
* is not supported by this collection
* @throws ClassCastException if the class of the specified element
* prevents it from being added to this collection
* @throws NullPointerException if the specified element is null and this
* collection does not permit null elements
@@ -289,38 +289,38 @@
boolean add(E e);
/**
* Removes a single instance of the specified element from this
* collection, if it is present (optional operation). More formally,
- * removes an element <tt>e</tt> such that
- * <tt>(o==null ? e==null : o.equals(e))</tt>, if
+ * removes an element {@code e} such that
+ * <code>(o==null ? e==null : o.equals(e))</code>, if
* this collection contains one or more such elements. Returns
- * <tt>true</tt> if this collection contained the specified element (or
+ * {@code true} if this collection contained the specified element (or
* equivalently, if this collection changed as a result of the call).
*
* @param o element to be removed from this collection, if present
- * @return <tt>true</tt> if an element was removed as a result of this call
+ * @return {@code true} if an element was removed as a result of this call
* @throws ClassCastException if the type of the specified element
* is incompatible with this collection
* (<a href="#optional-restrictions">optional</a>)
* @throws NullPointerException if the specified element is null and this
* collection does not permit null elements
* (<a href="#optional-restrictions">optional</a>)
- * @throws UnsupportedOperationException if the <tt>remove</tt> operation
+ * @throws UnsupportedOperationException if the {@code remove} operation
* is not supported by this collection
*/
boolean remove(Object o);
// Bulk Operations
/**
- * Returns <tt>true</tt> if this collection contains all of the elements
+ * Returns {@code true} if this collection contains all of the elements
* in the specified collection.
*
* @param c collection to be checked for containment in this collection
- * @return <tt>true</tt> if this collection contains all of the elements
+ * @return {@code true} if this collection contains all of the elements
* in the specified collection
* @throws ClassCastException if the types of one or more elements
* in the specified collection are incompatible with this
* collection
* (<a href="#optional-restrictions">optional</a>)
@@ -340,12 +340,12 @@
* (This implies that the behavior of this call is undefined if the
* specified collection is this collection, and this collection is
* nonempty.)
*
* @param c collection containing elements to be added to this collection
- * @return <tt>true</tt> if this collection changed as a result of the call
- * @throws UnsupportedOperationException if the <tt>addAll</tt> operation
+ * @return {@code true} if this collection changed as a result of the call
+ * @throws UnsupportedOperationException if the {@code addAll} operation
* is not supported by this collection
* @throws ClassCastException if the class of an element of the specified
* collection prevents it from being added to this collection
* @throws NullPointerException if the specified collection contains a
* null element and this collection does not permit null elements,
@@ -364,13 +364,13 @@
* specified collection (optional operation). After this call returns,
* this collection will contain no elements in common with the specified
* collection.
*
* @param c collection containing elements to be removed from this collection
- * @return <tt>true</tt> if this collection changed as a result of the
+ * @return {@code true} if this collection changed as a result of the
* call
- * @throws UnsupportedOperationException if the <tt>removeAll</tt> method
+ * @throws UnsupportedOperationException if the {@code removeAll} method
* is not supported by this collection
* @throws ClassCastException if the types of one or more elements
* in this collection are incompatible with the specified
* collection
* (<a href="#optional-restrictions">optional</a>)
@@ -424,12 +424,12 @@
* specified collection (optional operation). In other words, removes from
* this collection all of its elements that are not contained in the
* specified collection.
*
* @param c collection containing elements to be retained in this collection
- * @return <tt>true</tt> if this collection changed as a result of the call
- * @throws UnsupportedOperationException if the <tt>retainAll</tt> operation
+ * @return {@code true} if this collection changed as a result of the call
+ * @throws UnsupportedOperationException if the {@code retainAll} operation
* is not supported by this collection
* @throws ClassCastException if the types of one or more elements
* in this collection are incompatible with the specified
* collection
* (<a href="#optional-restrictions">optional</a>)
@@ -445,62 +445,62 @@
/**
* Removes all of the elements from this collection (optional operation).
* The collection will be empty after this method returns.
*
- * @throws UnsupportedOperationException if the <tt>clear</tt> operation
+ * @throws UnsupportedOperationException if the {@code clear} operation
* is not supported by this collection
*/
void clear();
// Comparison and hashing
/**
* Compares the specified object with this collection for equality. <p>
*
- * While the <tt>Collection</tt> interface adds no stipulations to the
- * general contract for the <tt>Object.equals</tt>, programmers who
- * implement the <tt>Collection</tt> interface "directly" (in other words,
- * create a class that is a <tt>Collection</tt> but is not a <tt>Set</tt>
- * or a <tt>List</tt>) must exercise care if they choose to override the
- * <tt>Object.equals</tt>. It is not necessary to do so, and the simplest
- * course of action is to rely on <tt>Object</tt>'s implementation, but
+ * While the {@code Collection} interface adds no stipulations to the
+ * general contract for the {@code Object.equals}, programmers who
+ * implement the {@code Collection} interface "directly" (in other words,
+ * create a class that is a {@code Collection} but is not a {@code Set}
+ * or a {@code List}) must exercise care if they choose to override the
+ * {@code Object.equals}. It is not necessary to do so, and the simplest
+ * course of action is to rely on {@code Object}'s implementation, but
* the implementor may wish to implement a "value comparison" in place of
- * the default "reference comparison." (The <tt>List</tt> and
- * <tt>Set</tt> interfaces mandate such value comparisons.)<p>
+ * the default "reference comparison." (The {@code List} and
+ * {@code Set} interfaces mandate such value comparisons.)<p>
*
- * The general contract for the <tt>Object.equals</tt> method states that
- * equals must be symmetric (in other words, <tt>a.equals(b)</tt> if and
- * only if <tt>b.equals(a)</tt>). The contracts for <tt>List.equals</tt>
- * and <tt>Set.equals</tt> state that lists are only equal to other lists,
- * and sets to other sets. Thus, a custom <tt>equals</tt> method for a
- * collection class that implements neither the <tt>List</tt> nor
- * <tt>Set</tt> interface must return <tt>false</tt> when this collection
+ * The general contract for the {@code Object.equals} method states that
+ * equals must be symmetric (in other words, {@code a.equals(b)} if and
+ * only if {@code b.equals(a)}). The contracts for {@code List.equals}
+ * and {@code Set.equals} state that lists are only equal to other lists,
+ * and sets to other sets. Thus, a custom {@code equals} method for a
+ * collection class that implements neither the {@code List} nor
+ * {@code Set} interface must return {@code false} when this collection
* is compared to any list or set. (By the same logic, it is not possible
- * to write a class that correctly implements both the <tt>Set</tt> and
- * <tt>List</tt> interfaces.)
+ * to write a class that correctly implements both the {@code Set} and
+ * {@code List} interfaces.)
*
* @param o object to be compared for equality with this collection
- * @return <tt>true</tt> if the specified object is equal to this
+ * @return {@code true} if the specified object is equal to this
* collection
*
* @see Object#equals(Object)
* @see Set#equals(Object)
* @see List#equals(Object)
*/
boolean equals(Object o);
/**
* Returns the hash code value for this collection. While the
- * <tt>Collection</tt> interface adds no stipulations to the general
- * contract for the <tt>Object.hashCode</tt> method, programmers should
- * take note that any class that overrides the <tt>Object.equals</tt>
- * method must also override the <tt>Object.hashCode</tt> method in order
- * to satisfy the general contract for the <tt>Object.hashCode</tt> method.
- * In particular, <tt>c1.equals(c2)</tt> implies that
- * <tt>c1.hashCode()==c2.hashCode()</tt>.
+ * {@code Collection} interface adds no stipulations to the general
+ * contract for the {@code Object.hashCode} method, programmers should
+ * take note that any class that overrides the {@code Object.equals}
+ * method must also override the {@code Object.hashCode} method in order
+ * to satisfy the general contract for the {@code Object.hashCode} method.
+ * In particular, {@code c1.equals(c2)} implies that
+ * {@code c1.hashCode()==c2.hashCode()}.
*
* @return the hash code value for this collection
*
* @see Object#hashCode()
* @see Object#equals(Object)
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