author | mcimadamore |
Tue, 13 Jan 2009 13:27:14 +0000 | |
changeset 1789 | 7ac8c0815000 |
parent 10 | 06bc494ca11e |
child 5520 | 86e4b9a9da40 |
permissions | -rw-r--r-- |
10 | 1 |
/* |
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* Copyright 1999-2006 Sun Microsystems, Inc. All Rights Reserved. |
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* DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER. |
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* |
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* This code is free software; you can redistribute it and/or modify it |
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* under the terms of the GNU General Public License version 2 only, as |
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* published by the Free Software Foundation. Sun designates this |
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* particular file as subject to the "Classpath" exception as provided |
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* by Sun in the LICENSE file that accompanied this code. |
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* |
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* This code is distributed in the hope that it will be useful, but WITHOUT |
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* ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or |
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* FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License |
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* version 2 for more details (a copy is included in the LICENSE file that |
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* accompanied this code). |
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* |
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* You should have received a copy of the GNU General Public License version |
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* 2 along with this work; if not, write to the Free Software Foundation, |
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* Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA. |
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* |
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* Please contact Sun Microsystems, Inc., 4150 Network Circle, Santa Clara, |
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* CA 95054 USA or visit www.sun.com if you need additional information or |
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* have any questions. |
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*/ |
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package com.sun.tools.javac.util; |
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import java.lang.reflect.Array; |
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import java.util.ArrayList; |
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import java.util.Collection; |
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import java.util.Collections; |
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import java.util.Iterator; |
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import java.util.AbstractCollection; |
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import java.util.ListIterator; |
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import java.util.NoSuchElementException; |
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||
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/** A class for generic linked lists. Links are supposed to be |
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* immutable, the only exception being the incremental construction of |
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* lists via ListBuffers. List is the main container class in |
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* GJC. Most data structures and algorthms in GJC use lists rather |
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* than arrays. |
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* |
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* <p>Lists are always trailed by a sentinel element, whose head and tail |
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* are both null. |
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* |
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* <p><b>This is NOT part of any API supported by Sun Microsystems. If |
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* you write code that depends on this, you do so at your own risk. |
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* This code and its internal interfaces are subject to change or |
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* deletion without notice.</b> |
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*/ |
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public class List<A> extends AbstractCollection<A> implements java.util.List<A> { |
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||
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/** The first element of the list, supposed to be immutable. |
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*/ |
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public A head; |
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/** The remainder of the list except for its first element, supposed |
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* to be immutable. |
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*/ |
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//@Deprecated |
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public List<A> tail; |
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||
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/** Construct a list given its head and tail. |
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*/ |
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List(A head, List<A> tail) { |
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this.tail = tail; |
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this.head = head; |
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} |
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||
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/** Construct an empty list. |
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*/ |
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@SuppressWarnings("unchecked") |
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public static <A> List<A> nil() { |
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parents:
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diff
changeset
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return (List<A>)EMPTY_LIST; |
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} |
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7ac8c0815000
6765045: Remove rawtypes warnings from langtools
mcimadamore
parents:
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7ac8c0815000
6765045: Remove rawtypes warnings from langtools
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private static List<?> EMPTY_LIST = new List<Object>(null,null) { |
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public List<Object> setTail(List<Object> tail) { |
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throw new UnsupportedOperationException(); |
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} |
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public boolean isEmpty() { |
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return true; |
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} |
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}; |
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/** Construct a list consisting of given element. |
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*/ |
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public static <A> List<A> of(A x1) { |
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return new List<A>(x1, List.<A>nil()); |
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} |
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/** Construct a list consisting of given elements. |
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*/ |
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public static <A> List<A> of(A x1, A x2) { |
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return new List<A>(x1, of(x2)); |
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} |
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/** Construct a list consisting of given elements. |
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*/ |
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public static <A> List<A> of(A x1, A x2, A x3) { |
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return new List<A>(x1, of(x2, x3)); |
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} |
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/** Construct a list consisting of given elements. |
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*/ |
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public static <A> List<A> of(A x1, A x2, A x3, A... rest) { |
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return new List<A>(x1, new List<A>(x2, new List<A>(x3, from(rest)))); |
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} |
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/** |
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* Construct a list consisting all elements of given array. |
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* @param array an array; if {@code null} return an empty list |
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*/ |
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public static <A> List<A> from(A[] array) { |
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List<A> xs = nil(); |
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if (array != null) |
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for (int i = array.length - 1; i >= 0; i--) |
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xs = new List<A>(array[i], xs); |
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return xs; |
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} |
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/** Construct a list consisting of a given number of identical elements. |
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* @param len The number of elements in the list. |
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* @param init The value of each element. |
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*/ |
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@Deprecated |
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public static <A> List<A> fill(int len, A init) { |
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List<A> l = nil(); |
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for (int i = 0; i < len; i++) l = new List<A>(init, l); |
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return l; |
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} |
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/** Does list have no elements? |
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*/ |
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@Override |
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public boolean isEmpty() { |
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return tail == null; |
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} |
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||
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/** Does list have elements? |
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*/ |
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//@Deprecated |
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public boolean nonEmpty() { |
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return tail != null; |
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} |
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/** Return the number of elements in this list. |
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*/ |
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//@Deprecated |
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public int length() { |
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List<A> l = this; |
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int len = 0; |
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while (l.tail != null) { |
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l = l.tail; |
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len++; |
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} |
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return len; |
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} |
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@Override |
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public int size() { |
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return length(); |
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} |
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public List<A> setTail(List<A> tail) { |
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this.tail = tail; |
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return tail; |
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} |
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/** Prepend given element to front of list, forming and returning |
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* a new list. |
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*/ |
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public List<A> prepend(A x) { |
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return new List<A>(x, this); |
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} |
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/** Prepend given list of elements to front of list, forming and returning |
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* a new list. |
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*/ |
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public List<A> prependList(List<A> xs) { |
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if (this.isEmpty()) return xs; |
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if (xs.isEmpty()) return this; |
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if (xs.tail.isEmpty()) return prepend(xs.head); |
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// return this.prependList(xs.tail).prepend(xs.head); |
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List<A> result = this; |
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List<A> rev = xs.reverse(); |
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assert rev != xs; |
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// since xs.reverse() returned a new list, we can reuse the |
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// individual List objects, instead of allocating new ones. |
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while (rev.nonEmpty()) { |
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List<A> h = rev; |
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rev = rev.tail; |
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h.setTail(result); |
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result = h; |
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} |
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return result; |
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} |
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/** Reverse list. |
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* If the list is empty or a singleton, then the same list is returned. |
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* Otherwise a new list is formed. |
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*/ |
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public List<A> reverse() { |
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// if it is empty or a singleton, return itself |
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if (isEmpty() || tail.isEmpty()) |
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return this; |
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List<A> rev = nil(); |
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for (List<A> l = this; l.nonEmpty(); l = l.tail) |
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rev = new List<A>(l.head, rev); |
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return rev; |
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} |
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/** Append given element at length, forming and returning |
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* a new list. |
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*/ |
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public List<A> append(A x) { |
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return of(x).prependList(this); |
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} |
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/** Append given list at length, forming and returning |
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* a new list. |
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*/ |
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public List<A> appendList(List<A> x) { |
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return x.prependList(this); |
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} |
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/** |
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* Append given list buffer at length, forming and returning a new |
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* list. |
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*/ |
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public List<A> appendList(ListBuffer<A> x) { |
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return appendList(x.toList()); |
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} |
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/** Copy successive elements of this list into given vector until |
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* list is exhausted or end of vector is reached. |
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*/ |
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@Override @SuppressWarnings("unchecked") |
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public <T> T[] toArray(T[] vec) { |
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int i = 0; |
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List<A> l = this; |
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Object[] dest = vec; |
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while (l.nonEmpty() && i < vec.length) { |
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dest[i] = l.head; |
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l = l.tail; |
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i++; |
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} |
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if (l.isEmpty()) { |
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if (i < vec.length) |
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vec[i] = null; |
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return vec; |
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} |
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vec = (T[])Array.newInstance(vec.getClass().getComponentType(), size()); |
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return toArray(vec); |
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} |
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||
258 |
public Object[] toArray() { |
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return toArray(new Object[size()]); |
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} |
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||
262 |
/** Form a string listing all elements with given separator character. |
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*/ |
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264 |
public String toString(String sep) { |
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265 |
if (isEmpty()) { |
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return ""; |
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} else { |
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StringBuffer buf = new StringBuffer(); |
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buf.append(head); |
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for (List<A> l = tail; l.nonEmpty(); l = l.tail) { |
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buf.append(sep); |
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buf.append(l.head); |
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} |
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return buf.toString(); |
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} |
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} |
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||
278 |
/** Form a string listing all elements with comma as the separator character. |
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*/ |
|
280 |
@Override |
|
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public String toString() { |
|
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return toString(","); |
|
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} |
|
284 |
||
285 |
/** Compute a hash code, overrides Object |
|
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* @see java.util.List#hashCode |
|
287 |
*/ |
|
288 |
@Override |
|
289 |
public int hashCode() { |
|
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List<A> l = this; |
|
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int h = 1; |
|
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while (l.tail != null) { |
|
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h = h * 31 + (l.head == null ? 0 : l.head.hashCode()); |
|
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l = l.tail; |
|
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} |
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return h; |
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297 |
} |
|
298 |
||
299 |
/** Is this list the same as other list? |
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* @see java.util.List#equals |
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*/ |
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302 |
@Override |
|
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public boolean equals(Object other) { |
|
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if (other instanceof List<?>) |
|
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return equals(this, (List<?>)other); |
|
306 |
if (other instanceof java.util.List<?>) { |
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List<A> t = this; |
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Iterator<?> oIter = ((java.util.List<?>) other).iterator(); |
|
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while (t.tail != null && oIter.hasNext()) { |
|
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Object o = oIter.next(); |
|
311 |
if ( !(t.head == null ? o == null : t.head.equals(o))) |
|
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return false; |
|
313 |
t = t.tail; |
|
314 |
} |
|
315 |
return (t.isEmpty() && !oIter.hasNext()); |
|
316 |
} |
|
317 |
return false; |
|
318 |
} |
|
319 |
||
320 |
/** Are the two lists the same? |
|
321 |
*/ |
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1789
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mcimadamore
parents:
10
diff
changeset
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public static boolean equals(List<?> xs, List<?> ys) { |
10 | 323 |
while (xs.tail != null && ys.tail != null) { |
324 |
if (xs.head == null) { |
|
325 |
if (ys.head != null) return false; |
|
326 |
} else { |
|
327 |
if (!xs.head.equals(ys.head)) return false; |
|
328 |
} |
|
329 |
xs = xs.tail; |
|
330 |
ys = ys.tail; |
|
331 |
} |
|
332 |
return xs.tail == null && ys.tail == null; |
|
333 |
} |
|
334 |
||
335 |
/** Does the list contain the specified element? |
|
336 |
*/ |
|
337 |
@Override |
|
338 |
public boolean contains(Object x) { |
|
339 |
List<A> l = this; |
|
340 |
while (l.tail != null) { |
|
341 |
if (x == null) { |
|
342 |
if (l.head == null) return true; |
|
343 |
} else { |
|
344 |
if (l.head.equals(x)) return true; |
|
345 |
} |
|
346 |
l = l.tail; |
|
347 |
} |
|
348 |
return false; |
|
349 |
} |
|
350 |
||
351 |
/** The last element in the list, if any, or null. |
|
352 |
*/ |
|
353 |
public A last() { |
|
354 |
A last = null; |
|
355 |
List<A> t = this; |
|
356 |
while (t.tail != null) { |
|
357 |
last = t.head; |
|
358 |
t = t.tail; |
|
359 |
} |
|
360 |
return last; |
|
361 |
} |
|
362 |
||
363 |
@SuppressWarnings("unchecked") |
|
364 |
public static <T> List<T> convert(Class<T> klass, List<?> list) { |
|
365 |
if (list == null) |
|
366 |
return null; |
|
367 |
for (Object o : list) |
|
368 |
klass.cast(o); |
|
369 |
return (List<T>)list; |
|
370 |
} |
|
371 |
||
1789
7ac8c0815000
6765045: Remove rawtypes warnings from langtools
mcimadamore
parents:
10
diff
changeset
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372 |
private static Iterator<?> EMPTYITERATOR = new Iterator<Object>() { |
10 | 373 |
public boolean hasNext() { |
374 |
return false; |
|
375 |
} |
|
376 |
public Object next() { |
|
377 |
throw new java.util.NoSuchElementException(); |
|
378 |
} |
|
379 |
public void remove() { |
|
380 |
throw new UnsupportedOperationException(); |
|
381 |
} |
|
382 |
}; |
|
383 |
||
384 |
@SuppressWarnings("unchecked") |
|
385 |
private static <A> Iterator<A> emptyIterator() { |
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386 |
return (Iterator<A>)EMPTYITERATOR; |
10 | 387 |
} |
388 |
||
389 |
@Override |
|
390 |
public Iterator<A> iterator() { |
|
391 |
if (tail == null) |
|
392 |
return emptyIterator(); |
|
393 |
return new Iterator<A>() { |
|
394 |
List<A> elems = List.this; |
|
395 |
public boolean hasNext() { |
|
396 |
return elems.tail != null; |
|
397 |
} |
|
398 |
public A next() { |
|
399 |
if (elems.tail == null) |
|
400 |
throw new NoSuchElementException(); |
|
401 |
A result = elems.head; |
|
402 |
elems = elems.tail; |
|
403 |
return result; |
|
404 |
} |
|
405 |
public void remove() { |
|
406 |
throw new UnsupportedOperationException(); |
|
407 |
} |
|
408 |
}; |
|
409 |
} |
|
410 |
||
411 |
public A get(int index) { |
|
412 |
if (index < 0) |
|
413 |
throw new IndexOutOfBoundsException(String.valueOf(index)); |
|
414 |
||
415 |
List<A> l = this; |
|
416 |
for (int i = index; i-- > 0 && !l.isEmpty(); l = l.tail) |
|
417 |
; |
|
418 |
||
419 |
if (l.isEmpty()) |
|
420 |
throw new IndexOutOfBoundsException("Index: " + index + ", " + |
|
421 |
"Size: " + size()); |
|
422 |
return l.head; |
|
423 |
} |
|
424 |
||
425 |
public boolean addAll(int index, Collection<? extends A> c) { |
|
426 |
if (c.isEmpty()) |
|
427 |
return false; |
|
428 |
throw new UnsupportedOperationException(); |
|
429 |
} |
|
430 |
||
431 |
public A set(int index, A element) { |
|
432 |
throw new UnsupportedOperationException(); |
|
433 |
} |
|
434 |
||
435 |
public void add(int index, A element) { |
|
436 |
throw new UnsupportedOperationException(); |
|
437 |
} |
|
438 |
||
439 |
public A remove(int index) { |
|
440 |
throw new UnsupportedOperationException(); |
|
441 |
} |
|
442 |
||
443 |
public int indexOf(Object o) { |
|
444 |
int i = 0; |
|
445 |
for (List<A> l = this; l.tail != null; l = l.tail, i++) { |
|
446 |
if (l.head == null ? o == null : l.head.equals(o)) |
|
447 |
return i; |
|
448 |
} |
|
449 |
return -1; |
|
450 |
} |
|
451 |
||
452 |
public int lastIndexOf(Object o) { |
|
453 |
int last = -1; |
|
454 |
int i = 0; |
|
455 |
for (List<A> l = this; l.tail != null; l = l.tail, i++) { |
|
456 |
if (l.head == null ? o == null : l.head.equals(o)) |
|
457 |
last = i; |
|
458 |
} |
|
459 |
return last; |
|
460 |
} |
|
461 |
||
462 |
public ListIterator<A> listIterator() { |
|
463 |
return Collections.unmodifiableList(new ArrayList<A>(this)).listIterator(); |
|
464 |
} |
|
465 |
||
466 |
public ListIterator<A> listIterator(int index) { |
|
467 |
return Collections.unmodifiableList(new ArrayList<A>(this)).listIterator(index); |
|
468 |
} |
|
469 |
||
470 |
public java.util.List<A> subList(int fromIndex, int toIndex) { |
|
471 |
if (fromIndex < 0 || toIndex > size() || fromIndex > toIndex) |
|
472 |
throw new IllegalArgumentException(); |
|
473 |
||
474 |
ArrayList<A> a = new ArrayList<A>(toIndex - fromIndex); |
|
475 |
int i = 0; |
|
476 |
for (List<A> l = this; l.tail != null; l = l.tail, i++) { |
|
477 |
if (i == toIndex) |
|
478 |
break; |
|
479 |
if (i >= fromIndex) |
|
480 |
a.add(l.head); |
|
481 |
} |
|
482 |
||
483 |
return Collections.unmodifiableList(a); |
|
484 |
} |
|
485 |
} |