diff -r 5be31d9fa455 -r d382dacfd73f rt/emul/compact/src/main/java/java/util/List.java --- /dev/null Thu Jan 01 00:00:00 1970 +0000 +++ b/rt/emul/compact/src/main/java/java/util/List.java Tue Feb 26 16:54:16 2013 +0100 @@ -0,0 +1,600 @@ +/* + * Copyright (c) 1997, 2010, Oracle and/or its affiliates. All rights reserved. + * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER. + * + * This code is free software; you can redistribute it and/or modify it + * under the terms of the GNU General Public License version 2 only, as + * published by the Free Software Foundation. Oracle designates this + * particular file as subject to the "Classpath" exception as provided + * by Oracle in the LICENSE file that accompanied this code. + * + * This code is distributed in the hope that it will be useful, but WITHOUT + * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or + * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License + * version 2 for more details (a copy is included in the LICENSE file that + * accompanied this code). + * + * You should have received a copy of the GNU General Public License version + * 2 along with this work; if not, write to the Free Software Foundation, + * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA. + * + * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA + * or visit www.oracle.com if you need additional information or have any + * questions. + */ + +package java.util; + +/** + * An ordered collection (also known as a sequence). The user of this + * interface has precise control over where in the list each element is + * inserted. The user can access elements by their integer index (position in + * the list), and search for elements in the list.

+ * + * Unlike sets, lists typically allow duplicate elements. More formally, + * lists typically allow pairs of elements e1 and e2 + * such that e1.equals(e2), and they typically allow multiple + * null elements if they allow null elements at all. It is not inconceivable + * that someone might wish to implement a list that prohibits duplicates, by + * throwing runtime exceptions when the user attempts to insert them, but we + * expect this usage to be rare.

+ * + * The List interface places additional stipulations, beyond those + * specified in the Collection interface, on the contracts of the + * iterator, add, remove, equals, and + * hashCode methods. Declarations for other inherited methods are + * also included here for convenience.

+ * + * The List interface provides four methods for positional (indexed) + * access to list elements. Lists (like Java arrays) are zero based. Note + * that these operations may execute in time proportional to the index value + * for some implementations (the LinkedList class, for + * example). Thus, iterating over the elements in a list is typically + * preferable to indexing through it if the caller does not know the + * implementation.

+ * + * The List interface provides a special iterator, called a + * ListIterator, that allows element insertion and replacement, and + * bidirectional access in addition to the normal operations that the + * Iterator interface provides. A method is provided to obtain a + * list iterator that starts at a specified position in the list.

+ * + * The List interface provides two methods to search for a specified + * object. From a performance standpoint, these methods should be used with + * caution. In many implementations they will perform costly linear + * searches.

+ * + * The List interface provides two methods to efficiently insert and + * remove multiple elements at an arbitrary point in the list.

+ * + * Note: While it is permissible for lists to contain themselves as elements, + * extreme caution is advised: the equals and hashCode + * methods are no longer well defined on such a list. + * + *

Some list implementations have restrictions on the elements that + * they may contain. 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 + * NullPointerException or 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 list may throw an + * exception or it may succeed, at the option of the implementation. + * Such exceptions are marked as "optional" in the specification for this + * interface. + * + *

This interface is a member of the + * + * Java Collections Framework. + * + * @param the type of elements in this list + * + * @author Josh Bloch + * @author Neal Gafter + * @see Collection + * @see Set + * @see ArrayList + * @see LinkedList + * @see Vector + * @see Arrays#asList(Object[]) + * @see Collections#nCopies(int, Object) + * @see Collections#EMPTY_LIST + * @see AbstractList + * @see AbstractSequentialList + * @since 1.2 + */ + +public interface List extends Collection { + // Query Operations + + /** + * Returns the number of elements in this list. If this list contains + * more than Integer.MAX_VALUE elements, returns + * Integer.MAX_VALUE. + * + * @return the number of elements in this list + */ + int size(); + + /** + * Returns true if this list contains no elements. + * + * @return true if this list contains no elements + */ + boolean isEmpty(); + + /** + * Returns true if this list contains the specified element. + * More formally, returns true if and only if this list contains + * at least one element e such that + * (o==null ? e==null : o.equals(e)). + * + * @param o element whose presence in this list is to be tested + * @return true if this list contains the specified element + * @throws ClassCastException if the type of the specified element + * is incompatible with this list + * (optional) + * @throws NullPointerException if the specified element is null and this + * list does not permit null elements + * (optional) + */ + boolean contains(Object o); + + /** + * Returns an iterator over the elements in this list in proper sequence. + * + * @return an iterator over the elements in this list in proper sequence + */ + Iterator iterator(); + + /** + * Returns an array containing all of the elements in this list in proper + * sequence (from first to last element). + * + *

The returned array will be "safe" in that no references to it are + * maintained by this list. (In other words, this method must + * allocate a new array even if this list is backed by an array). + * The caller is thus free to modify the returned array. + * + *

This method acts as bridge between array-based and collection-based + * APIs. + * + * @return an array containing all of the elements in this list in proper + * sequence + * @see Arrays#asList(Object[]) + */ + Object[] toArray(); + + /** + * Returns an array containing all of the elements in this list in + * proper sequence (from first to last element); the runtime type of + * the returned array is that of the specified array. If the list fits + * in the specified array, it is returned therein. Otherwise, a new + * array is allocated with the runtime type of the specified array and + * the size of this list. + * + *

If the list fits in the specified array with room to spare (i.e., + * the array has more elements than the list), the element in the array + * immediately following the end of the list is set to null. + * (This is useful in determining the length of the list only if + * the caller knows that the list does not contain any null elements.) + * + *

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. + * + *

Suppose x is a list known to contain only strings. + * The following code can be used to dump the list into a newly + * allocated array of String: + * + * 

+     *     String[] y = x.toArray(new String[0]);
+ * + * Note that toArray(new Object[0]) is identical in function to + * toArray(). + * + * @param a the array into which the elements of this list are to + * be stored, if it is big enough; otherwise, a new array of the + * same runtime type is allocated for this purpose. + * @return an array containing the elements of this list + * @throws ArrayStoreException if the runtime type of the specified array + * is not a supertype of the runtime type of every element in + * this list + * @throws NullPointerException if the specified array is null + */ + T[] toArray(T[] a); + + + // Modification Operations + + /** + * Appends the specified element to the end of this list (optional + * operation). + * + *

Lists that support this operation may place limitations on what + * elements may be added to this list. In particular, some + * lists will refuse to add null elements, and others will impose + * restrictions on the type of elements that may be added. List + * classes should clearly specify in their documentation any restrictions + * on what elements may be added. + * + * @param e element to be appended to this list + * @return true (as specified by {@link Collection#add}) + * @throws UnsupportedOperationException if the add operation + * is not supported by this list + * @throws ClassCastException if the class of the specified element + * prevents it from being added to this list + * @throws NullPointerException if the specified element is null and this + * list does not permit null elements + * @throws IllegalArgumentException if some property of this element + * prevents it from being added to this list + */ + boolean add(E e); + + /** + * Removes the first occurrence of the specified element from this list, + * if it is present (optional operation). If this list does not contain + * the element, it is unchanged. More formally, removes the element with + * the lowest index i such that + * (o==null ? get(i)==null : o.equals(get(i))) + * (if such an element exists). Returns true if this list + * contained the specified element (or equivalently, if this list changed + * as a result of the call). + * + * @param o element to be removed from this list, if present + * @return true if this list contained the specified element + * @throws ClassCastException if the type of the specified element + * is incompatible with this list + * (optional) + * @throws NullPointerException if the specified element is null and this + * list does not permit null elements + * (optional) + * @throws UnsupportedOperationException if the remove operation + * is not supported by this list + */ + boolean remove(Object o); + + + // Bulk Modification Operations + + /** + * Returns true if this list contains all of the elements of the + * specified collection. + * + * @param c collection to be checked for containment in this list + * @return true if this list contains all of the elements of the + * specified collection + * @throws ClassCastException if the types of one or more elements + * in the specified collection are incompatible with this + * list + * (optional) + * @throws NullPointerException if the specified collection contains one + * or more null elements and this list does not permit null + * elements + * (optional), + * or if the specified collection is null + * @see #contains(Object) + */ + boolean containsAll(Collection c); + + /** + * Appends all of the elements in the specified collection to the end of + * this list, in the order that they are returned by the specified + * collection's iterator (optional operation). The behavior of this + * operation is undefined if the specified collection is modified while + * the operation is in progress. (Note that this will occur if the + * specified collection is this list, and it's nonempty.) + * + * @param c collection containing elements to be added to this list + * @return true if this list changed as a result of the call + * @throws UnsupportedOperationException if the addAll operation + * is not supported by this list + * @throws ClassCastException if the class of an element of the specified + * collection prevents it from being added to this list + * @throws NullPointerException if the specified collection contains one + * or more null elements and this list does not permit null + * elements, or if the specified collection is null + * @throws IllegalArgumentException if some property of an element of the + * specified collection prevents it from being added to this list + * @see #add(Object) + */ + boolean addAll(Collection c); + + /** + * Inserts all of the elements in the specified collection into this + * list at the specified position (optional operation). Shifts the + * element currently at that position (if any) and any subsequent + * elements to the right (increases their indices). The new elements + * will appear in this list in the order that they are returned by the + * specified collection's iterator. The behavior of this operation is + * undefined if the specified collection is modified while the + * operation is in progress. (Note that this will occur if the specified + * collection is this list, and it's nonempty.) + * + * @param index index at which to insert the first element from the + * specified collection + * @param c collection containing elements to be added to this list + * @return true if this list changed as a result of the call + * @throws UnsupportedOperationException if the addAll operation + * is not supported by this list + * @throws ClassCastException if the class of an element of the specified + * collection prevents it from being added to this list + * @throws NullPointerException if the specified collection contains one + * or more null elements and this list does not permit null + * elements, or if the specified collection is null + * @throws IllegalArgumentException if some property of an element of the + * specified collection prevents it from being added to this list + * @throws IndexOutOfBoundsException if the index is out of range + * (index < 0 || index > size()) + */ + boolean addAll(int index, Collection c); + + /** + * Removes from this list all of its elements that are contained in the + * specified collection (optional operation). + * + * @param c collection containing elements to be removed from this list + * @return true if this list changed as a result of the call + * @throws UnsupportedOperationException if the removeAll operation + * is not supported by this list + * @throws ClassCastException if the class of an element of this list + * is incompatible with the specified collection + * (optional) + * @throws NullPointerException if this list contains a null element and the + * specified collection does not permit null elements + * (optional), + * or if the specified collection is null + * @see #remove(Object) + * @see #contains(Object) + */ + boolean removeAll(Collection c); + + /** + * Retains only the elements in this list that are contained in the + * specified collection (optional operation). In other words, removes + * from this list all of its elements that are not contained in the + * specified collection. + * + * @param c collection containing elements to be retained in this list + * @return true if this list changed as a result of the call + * @throws UnsupportedOperationException if the retainAll operation + * is not supported by this list + * @throws ClassCastException if the class of an element of this list + * is incompatible with the specified collection + * (optional) + * @throws NullPointerException if this list contains a null element and the + * specified collection does not permit null elements + * (optional), + * or if the specified collection is null + * @see #remove(Object) + * @see #contains(Object) + */ + boolean retainAll(Collection c); + + /** + * Removes all of the elements from this list (optional operation). + * The list will be empty after this call returns. + * + * @throws UnsupportedOperationException if the clear operation + * is not supported by this list + */ + void clear(); + + + // Comparison and hashing + + /** + * Compares the specified object with this list for equality. Returns + * true if and only if the specified object is also a list, both + * lists have the same size, and all corresponding pairs of elements in + * the two lists are equal. (Two elements e1 and + * e2 are equal if (e1==null ? e2==null : + * e1.equals(e2)).) In other words, two lists are defined to be + * equal if they contain the same elements in the same order. This + * definition ensures that the equals method works properly across + * different implementations of the List interface. + * + * @param o the object to be compared for equality with this list + * @return true if the specified object is equal to this list + */ + boolean equals(Object o); + + /** + * Returns the hash code value for this list. The hash code of a list + * is defined to be the result of the following calculation: + * 

+     *  int hashCode = 1;
+     *  for (E e : list)
+     *      hashCode = 31*hashCode + (e==null ? 0 : e.hashCode());
+     *
+ * This ensures that list1.equals(list2) implies that + * list1.hashCode()==list2.hashCode() for any two lists, + * list1 and list2, as required by the general + * contract of {@link Object#hashCode}. + * + * @return the hash code value for this list + * @see Object#equals(Object) + * @see #equals(Object) + */ + int hashCode(); + + + // Positional Access Operations + + /** + * Returns the element at the specified position in this list. + * + * @param index index of the element to return + * @return the element at the specified position in this list + * @throws IndexOutOfBoundsException if the index is out of range + * (index < 0 || index >= size()) + */ + E get(int index); + + /** + * Replaces the element at the specified position in this list with the + * specified element (optional operation). + * + * @param index index of the element to replace + * @param element element to be stored at the specified position + * @return the element previously at the specified position + * @throws UnsupportedOperationException if the set operation + * is not supported by this list + * @throws ClassCastException if the class of the specified element + * prevents it from being added to this list + * @throws NullPointerException if the specified element is null and + * this list does not permit null elements + * @throws IllegalArgumentException if some property of the specified + * element prevents it from being added to this list + * @throws IndexOutOfBoundsException if the index is out of range + * (index < 0 || index >= size()) + */ + E set(int index, E element); + + /** + * Inserts the specified element at the specified position in this list + * (optional operation). Shifts the element currently at that position + * (if any) and any subsequent elements to the right (adds one to their + * indices). + * + * @param index index at which the specified element is to be inserted + * @param element element to be inserted + * @throws UnsupportedOperationException if the add operation + * is not supported by this list + * @throws ClassCastException if the class of the specified element + * prevents it from being added to this list + * @throws NullPointerException if the specified element is null and + * this list does not permit null elements + * @throws IllegalArgumentException if some property of the specified + * element prevents it from being added to this list + * @throws IndexOutOfBoundsException if the index is out of range + * (index < 0 || index > size()) + */ + void add(int index, E element); + + /** + * Removes the element at the specified position in this list (optional + * operation). Shifts any subsequent elements to the left (subtracts one + * from their indices). Returns the element that was removed from the + * list. + * + * @param index the index of the element to be removed + * @return the element previously at the specified position + * @throws UnsupportedOperationException if the remove operation + * is not supported by this list + * @throws IndexOutOfBoundsException if the index is out of range + * (index < 0 || index >= size()) + */ + E remove(int index); + + + // Search Operations + + /** + * Returns the index of the first occurrence of the specified element + * in this list, or -1 if this list does not contain the element. + * More formally, returns the lowest index i such that + * (o==null ? get(i)==null : o.equals(get(i))), + * or -1 if there is no such index. + * + * @param o element to search for + * @return the index of the first occurrence of the specified element in + * this list, or -1 if this list does not contain the element + * @throws ClassCastException if the type of the specified element + * is incompatible with this list + * (optional) + * @throws NullPointerException if the specified element is null and this + * list does not permit null elements + * (optional) + */ + int indexOf(Object o); + + /** + * Returns the index of the last occurrence of the specified element + * in this list, or -1 if this list does not contain the element. + * More formally, returns the highest index i such that + * (o==null ? get(i)==null : o.equals(get(i))), + * or -1 if there is no such index. + * + * @param o element to search for + * @return the index of the last occurrence of the specified element in + * this list, or -1 if this list does not contain the element + * @throws ClassCastException if the type of the specified element + * is incompatible with this list + * (optional) + * @throws NullPointerException if the specified element is null and this + * list does not permit null elements + * (optional) + */ + int lastIndexOf(Object o); + + + // List Iterators + + /** + * Returns a list iterator over the elements in this list (in proper + * sequence). + * + * @return a list iterator over the elements in this list (in proper + * sequence) + */ + ListIterator listIterator(); + + /** + * Returns a list iterator over the elements in this list (in proper + * sequence), starting at the specified position in the list. + * The specified index indicates the first element that would be + * returned by an initial call to {@link ListIterator#next next}. + * An initial call to {@link ListIterator#previous previous} would + * return the element with the specified index minus one. + * + * @param index index of the first element to be returned from the + * list iterator (by a call to {@link ListIterator#next next}) + * @return a list iterator over the elements in this list (in proper + * sequence), starting at the specified position in the list + * @throws IndexOutOfBoundsException if the index is out of range + * ({@code index < 0 || index > size()}) + */ + ListIterator listIterator(int index); + + // View + + /** + * Returns a view of the portion of this list between the specified + * fromIndex, inclusive, and toIndex, exclusive. (If + * fromIndex and toIndex are equal, the returned list is + * empty.) The returned list is backed by this list, so non-structural + * changes in the returned list are reflected in this list, and vice-versa. + * The returned list supports all of the optional list operations supported + * by this list.

+ * + * This method eliminates the need for explicit range operations (of + * the sort that commonly exist for arrays). Any operation that expects + * a list can be used as a range operation by passing a subList view + * instead of a whole list. For example, the following idiom + * removes a range of elements from a list: + * 

+     *      list.subList(from, to).clear();
+     *
+ * Similar idioms may be constructed for indexOf and + * lastIndexOf, and all of the algorithms in the + * Collections class can be applied to a subList.

+ * + * The semantics of the list returned by this method become undefined if + * the backing list (i.e., this list) is structurally modified in + * any way other than via the returned list. (Structural modifications are + * those that change the size of this list, or otherwise perturb it in such + * a fashion that iterations in progress may yield incorrect results.) + * + * @param fromIndex low endpoint (inclusive) of the subList + * @param toIndex high endpoint (exclusive) of the subList + * @return a view of the specified range within this list + * @throws IndexOutOfBoundsException for an illegal endpoint index value + * (fromIndex < 0 || toIndex > size || + * fromIndex > toIndex) + */ + List subList(int fromIndex, int toIndex); +}