1.1 --- /dev/null Thu Jan 01 00:00:00 1970 +0000
1.2 +++ b/src/share/classes/com/sun/tools/javac/util/List.java Wed Apr 27 01:34:52 2016 +0800
1.3 @@ -0,0 +1,540 @@
1.4 +/*
1.5 + * Copyright (c) 1999, 2013, Oracle and/or its affiliates. All rights reserved.
1.6 + * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
1.7 + *
1.8 + * This code is free software; you can redistribute it and/or modify it
1.9 + * under the terms of the GNU General Public License version 2 only, as
1.10 + * published by the Free Software Foundation. Oracle designates this
1.11 + * particular file as subject to the "Classpath" exception as provided
1.12 + * by Oracle in the LICENSE file that accompanied this code.
1.13 + *
1.14 + * This code is distributed in the hope that it will be useful, but WITHOUT
1.15 + * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
1.16 + * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
1.17 + * version 2 for more details (a copy is included in the LICENSE file that
1.18 + * accompanied this code).
1.19 + *
1.20 + * You should have received a copy of the GNU General Public License version
1.21 + * 2 along with this work; if not, write to the Free Software Foundation,
1.22 + * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
1.23 + *
1.24 + * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
1.25 + * or visit www.oracle.com if you need additional information or have any
1.26 + * questions.
1.27 + */
1.28 +
1.29 +package com.sun.tools.javac.util;
1.30 +
1.31 +import java.lang.reflect.Array;
1.32 +import java.util.ArrayList;
1.33 +import java.util.Collection;
1.34 +import java.util.Collections;
1.35 +import java.util.Iterator;
1.36 +import java.util.AbstractCollection;
1.37 +import java.util.ListIterator;
1.38 +import java.util.NoSuchElementException;
1.39 +
1.40 +/** A class for generic linked lists. Links are supposed to be
1.41 + * immutable, the only exception being the incremental construction of
1.42 + * lists via ListBuffers. List is the main container class in
1.43 + * GJC. Most data structures and algorithms in GJC use lists rather
1.44 + * than arrays.
1.45 + *
1.46 + * <p>Lists are always trailed by a sentinel element, whose head and tail
1.47 + * are both null.
1.48 + *
1.49 + * <p><b>This is NOT part of any supported API.
1.50 + * If you write code that depends on this, you do so at your own risk.
1.51 + * This code and its internal interfaces are subject to change or
1.52 + * deletion without notice.</b>
1.53 + */
1.54 +public class List<A> extends AbstractCollection<A> implements java.util.List<A> {
1.55 +
1.56 + /** The first element of the list, supposed to be immutable.
1.57 + */
1.58 + public A head;
1.59 +
1.60 + /** The remainder of the list except for its first element, supposed
1.61 + * to be immutable.
1.62 + */
1.63 + //@Deprecated
1.64 + public List<A> tail;
1.65 +
1.66 + /** Construct a list given its head and tail.
1.67 + */
1.68 + List(A head, List<A> tail) {
1.69 + this.tail = tail;
1.70 + this.head = head;
1.71 + }
1.72 +
1.73 + /** Construct an empty list.
1.74 + */
1.75 + @SuppressWarnings("unchecked")
1.76 + public static <A> List<A> nil() {
1.77 + return (List<A>)EMPTY_LIST;
1.78 + }
1.79 +
1.80 + private static final List<?> EMPTY_LIST = new List<Object>(null,null) {
1.81 + public List<Object> setTail(List<Object> tail) {
1.82 + throw new UnsupportedOperationException();
1.83 + }
1.84 + public boolean isEmpty() {
1.85 + return true;
1.86 + }
1.87 + };
1.88 +
1.89 + /** Returns the list obtained from 'l' after removing all elements 'elem'
1.90 + */
1.91 + public static <A> List<A> filter(List<A> l, A elem) {
1.92 + Assert.checkNonNull(elem);
1.93 + List<A> res = List.nil();
1.94 + for (A a : l) {
1.95 + if (a != null && !a.equals(elem)) {
1.96 + res = res.prepend(a);
1.97 + }
1.98 + }
1.99 + return res.reverse();
1.100 + }
1.101 +
1.102 + public List<A> intersect(List<A> that) {
1.103 + ListBuffer<A> buf = new ListBuffer<>();
1.104 + for (A el : this) {
1.105 + if (that.contains(el)) {
1.106 + buf.append(el);
1.107 + }
1.108 + }
1.109 + return buf.toList();
1.110 + }
1.111 +
1.112 + public List<A> diff(List<A> that) {
1.113 + ListBuffer<A> buf = new ListBuffer<>();
1.114 + for (A el : this) {
1.115 + if (!that.contains(el)) {
1.116 + buf.append(el);
1.117 + }
1.118 + }
1.119 + return buf.toList();
1.120 + }
1.121 +
1.122 + /**
1.123 + * Create a new list from the first {@code n} elements of this list
1.124 + */
1.125 + public List<A> take(int n) {
1.126 + ListBuffer<A> buf = new ListBuffer<>();
1.127 + int count = 0;
1.128 + for (A el : this) {
1.129 + if (count++ == n) break;
1.130 + buf.append(el);
1.131 + }
1.132 + return buf.toList();
1.133 + }
1.134 +
1.135 + /** Construct a list consisting of given element.
1.136 + */
1.137 + public static <A> List<A> of(A x1) {
1.138 + return new List<A>(x1, List.<A>nil());
1.139 + }
1.140 +
1.141 + /** Construct a list consisting of given elements.
1.142 + */
1.143 + public static <A> List<A> of(A x1, A x2) {
1.144 + return new List<A>(x1, of(x2));
1.145 + }
1.146 +
1.147 + /** Construct a list consisting of given elements.
1.148 + */
1.149 + public static <A> List<A> of(A x1, A x2, A x3) {
1.150 + return new List<A>(x1, of(x2, x3));
1.151 + }
1.152 +
1.153 + /** Construct a list consisting of given elements.
1.154 + */
1.155 + @SuppressWarnings({"varargs", "unchecked"})
1.156 + public static <A> List<A> of(A x1, A x2, A x3, A... rest) {
1.157 + return new List<A>(x1, new List<A>(x2, new List<A>(x3, from(rest))));
1.158 + }
1.159 +
1.160 + /**
1.161 + * Construct a list consisting all elements of given array.
1.162 + * @param array an array; if {@code null} return an empty list
1.163 + */
1.164 + public static <A> List<A> from(A[] array) {
1.165 + List<A> xs = nil();
1.166 + if (array != null)
1.167 + for (int i = array.length - 1; i >= 0; i--)
1.168 + xs = new List<A>(array[i], xs);
1.169 + return xs;
1.170 + }
1.171 +
1.172 + public static <A> List<A> from(Iterable<? extends A> coll) {
1.173 + ListBuffer<A> xs = new ListBuffer<>();
1.174 + for (A a : coll) {
1.175 + xs.append(a);
1.176 + }
1.177 + return xs.toList();
1.178 + }
1.179 +
1.180 + /** Construct a list consisting of a given number of identical elements.
1.181 + * @param len The number of elements in the list.
1.182 + * @param init The value of each element.
1.183 + */
1.184 + @Deprecated
1.185 + public static <A> List<A> fill(int len, A init) {
1.186 + List<A> l = nil();
1.187 + for (int i = 0; i < len; i++) l = new List<A>(init, l);
1.188 + return l;
1.189 + }
1.190 +
1.191 + /** Does list have no elements?
1.192 + */
1.193 + @Override
1.194 + public boolean isEmpty() {
1.195 + return tail == null;
1.196 + }
1.197 +
1.198 + /** Does list have elements?
1.199 + */
1.200 + //@Deprecated
1.201 + public boolean nonEmpty() {
1.202 + return tail != null;
1.203 + }
1.204 +
1.205 + /** Return the number of elements in this list.
1.206 + */
1.207 + //@Deprecated
1.208 + public int length() {
1.209 + List<A> l = this;
1.210 + int len = 0;
1.211 + while (l.tail != null) {
1.212 + l = l.tail;
1.213 + len++;
1.214 + }
1.215 + return len;
1.216 + }
1.217 + @Override
1.218 + public int size() {
1.219 + return length();
1.220 + }
1.221 +
1.222 + public List<A> setTail(List<A> tail) {
1.223 + this.tail = tail;
1.224 + return tail;
1.225 + }
1.226 +
1.227 + /** Prepend given element to front of list, forming and returning
1.228 + * a new list.
1.229 + */
1.230 + public List<A> prepend(A x) {
1.231 + return new List<A>(x, this);
1.232 + }
1.233 +
1.234 + /** Prepend given list of elements to front of list, forming and returning
1.235 + * a new list.
1.236 + */
1.237 + public List<A> prependList(List<A> xs) {
1.238 + if (this.isEmpty()) return xs;
1.239 + if (xs.isEmpty()) return this;
1.240 + if (xs.tail.isEmpty()) return prepend(xs.head);
1.241 + // return this.prependList(xs.tail).prepend(xs.head);
1.242 + List<A> result = this;
1.243 + List<A> rev = xs.reverse();
1.244 + Assert.check(rev != xs);
1.245 + // since xs.reverse() returned a new list, we can reuse the
1.246 + // individual List objects, instead of allocating new ones.
1.247 + while (rev.nonEmpty()) {
1.248 + List<A> h = rev;
1.249 + rev = rev.tail;
1.250 + h.setTail(result);
1.251 + result = h;
1.252 + }
1.253 + return result;
1.254 + }
1.255 +
1.256 + /** Reverse list.
1.257 + * If the list is empty or a singleton, then the same list is returned.
1.258 + * Otherwise a new list is formed.
1.259 + */
1.260 + public List<A> reverse() {
1.261 + // if it is empty or a singleton, return itself
1.262 + if (isEmpty() || tail.isEmpty())
1.263 + return this;
1.264 +
1.265 + List<A> rev = nil();
1.266 + for (List<A> l = this; l.nonEmpty(); l = l.tail)
1.267 + rev = new List<A>(l.head, rev);
1.268 + return rev;
1.269 + }
1.270 +
1.271 + /** Append given element at length, forming and returning
1.272 + * a new list.
1.273 + */
1.274 + public List<A> append(A x) {
1.275 + return of(x).prependList(this);
1.276 + }
1.277 +
1.278 + /** Append given list at length, forming and returning
1.279 + * a new list.
1.280 + */
1.281 + public List<A> appendList(List<A> x) {
1.282 + return x.prependList(this);
1.283 + }
1.284 +
1.285 + /**
1.286 + * Append given list buffer at length, forming and returning a new
1.287 + * list.
1.288 + */
1.289 + public List<A> appendList(ListBuffer<A> x) {
1.290 + return appendList(x.toList());
1.291 + }
1.292 +
1.293 + /** Copy successive elements of this list into given vector until
1.294 + * list is exhausted or end of vector is reached.
1.295 + */
1.296 + @Override @SuppressWarnings("unchecked")
1.297 + public <T> T[] toArray(T[] vec) {
1.298 + int i = 0;
1.299 + List<A> l = this;
1.300 + Object[] dest = vec;
1.301 + while (l.nonEmpty() && i < vec.length) {
1.302 + dest[i] = l.head;
1.303 + l = l.tail;
1.304 + i++;
1.305 + }
1.306 + if (l.isEmpty()) {
1.307 + if (i < vec.length)
1.308 + vec[i] = null;
1.309 + return vec;
1.310 + }
1.311 +
1.312 + vec = (T[])Array.newInstance(vec.getClass().getComponentType(), size());
1.313 + return toArray(vec);
1.314 + }
1.315 +
1.316 + public Object[] toArray() {
1.317 + return toArray(new Object[size()]);
1.318 + }
1.319 +
1.320 + /** Form a string listing all elements with given separator character.
1.321 + */
1.322 + public String toString(String sep) {
1.323 + if (isEmpty()) {
1.324 + return "";
1.325 + } else {
1.326 + StringBuilder buf = new StringBuilder();
1.327 + buf.append(head);
1.328 + for (List<A> l = tail; l.nonEmpty(); l = l.tail) {
1.329 + buf.append(sep);
1.330 + buf.append(l.head);
1.331 + }
1.332 + return buf.toString();
1.333 + }
1.334 + }
1.335 +
1.336 + /** Form a string listing all elements with comma as the separator character.
1.337 + */
1.338 + @Override
1.339 + public String toString() {
1.340 + return toString(",");
1.341 + }
1.342 +
1.343 + /** Compute a hash code, overrides Object
1.344 + * @see java.util.List#hashCode
1.345 + */
1.346 + @Override
1.347 + public int hashCode() {
1.348 + List<A> l = this;
1.349 + int h = 1;
1.350 + while (l.tail != null) {
1.351 + h = h * 31 + (l.head == null ? 0 : l.head.hashCode());
1.352 + l = l.tail;
1.353 + }
1.354 + return h;
1.355 + }
1.356 +
1.357 + /** Is this list the same as other list?
1.358 + * @see java.util.List#equals
1.359 + */
1.360 + @Override
1.361 + public boolean equals(Object other) {
1.362 + if (other instanceof List<?>)
1.363 + return equals(this, (List<?>)other);
1.364 + if (other instanceof java.util.List<?>) {
1.365 + List<A> t = this;
1.366 + Iterator<?> oIter = ((java.util.List<?>) other).iterator();
1.367 + while (t.tail != null && oIter.hasNext()) {
1.368 + Object o = oIter.next();
1.369 + if ( !(t.head == null ? o == null : t.head.equals(o)))
1.370 + return false;
1.371 + t = t.tail;
1.372 + }
1.373 + return (t.isEmpty() && !oIter.hasNext());
1.374 + }
1.375 + return false;
1.376 + }
1.377 +
1.378 + /** Are the two lists the same?
1.379 + */
1.380 + public static boolean equals(List<?> xs, List<?> ys) {
1.381 + while (xs.tail != null && ys.tail != null) {
1.382 + if (xs.head == null) {
1.383 + if (ys.head != null) return false;
1.384 + } else {
1.385 + if (!xs.head.equals(ys.head)) return false;
1.386 + }
1.387 + xs = xs.tail;
1.388 + ys = ys.tail;
1.389 + }
1.390 + return xs.tail == null && ys.tail == null;
1.391 + }
1.392 +
1.393 + /** Does the list contain the specified element?
1.394 + */
1.395 + @Override
1.396 + public boolean contains(Object x) {
1.397 + List<A> l = this;
1.398 + while (l.tail != null) {
1.399 + if (x == null) {
1.400 + if (l.head == null) return true;
1.401 + } else {
1.402 + if (l.head.equals(x)) return true;
1.403 + }
1.404 + l = l.tail;
1.405 + }
1.406 + return false;
1.407 + }
1.408 +
1.409 + /** The last element in the list, if any, or null.
1.410 + */
1.411 + public A last() {
1.412 + A last = null;
1.413 + List<A> t = this;
1.414 + while (t.tail != null) {
1.415 + last = t.head;
1.416 + t = t.tail;
1.417 + }
1.418 + return last;
1.419 + }
1.420 +
1.421 + @SuppressWarnings("unchecked")
1.422 + public static <T> List<T> convert(Class<T> klass, List<?> list) {
1.423 + if (list == null)
1.424 + return null;
1.425 + for (Object o : list)
1.426 + klass.cast(o);
1.427 + return (List<T>)list;
1.428 + }
1.429 +
1.430 + private static final Iterator<?> EMPTYITERATOR = new Iterator<Object>() {
1.431 + public boolean hasNext() {
1.432 + return false;
1.433 + }
1.434 + public Object next() {
1.435 + throw new java.util.NoSuchElementException();
1.436 + }
1.437 + public void remove() {
1.438 + throw new UnsupportedOperationException();
1.439 + }
1.440 + };
1.441 +
1.442 + @SuppressWarnings("unchecked")
1.443 + private static <A> Iterator<A> emptyIterator() {
1.444 + return (Iterator<A>)EMPTYITERATOR;
1.445 + }
1.446 +
1.447 + @Override
1.448 + public Iterator<A> iterator() {
1.449 + if (tail == null)
1.450 + return emptyIterator();
1.451 + return new Iterator<A>() {
1.452 + List<A> elems = List.this;
1.453 + public boolean hasNext() {
1.454 + return elems.tail != null;
1.455 + }
1.456 + public A next() {
1.457 + if (elems.tail == null)
1.458 + throw new NoSuchElementException();
1.459 + A result = elems.head;
1.460 + elems = elems.tail;
1.461 + return result;
1.462 + }
1.463 + public void remove() {
1.464 + throw new UnsupportedOperationException();
1.465 + }
1.466 + };
1.467 + }
1.468 +
1.469 + public A get(int index) {
1.470 + if (index < 0)
1.471 + throw new IndexOutOfBoundsException(String.valueOf(index));
1.472 +
1.473 + List<A> l = this;
1.474 + for (int i = index; i-- > 0 && !l.isEmpty(); l = l.tail)
1.475 + ;
1.476 +
1.477 + if (l.isEmpty())
1.478 + throw new IndexOutOfBoundsException("Index: " + index + ", " +
1.479 + "Size: " + size());
1.480 + return l.head;
1.481 + }
1.482 +
1.483 + public boolean addAll(int index, Collection<? extends A> c) {
1.484 + if (c.isEmpty())
1.485 + return false;
1.486 + throw new UnsupportedOperationException();
1.487 + }
1.488 +
1.489 + public A set(int index, A element) {
1.490 + throw new UnsupportedOperationException();
1.491 + }
1.492 +
1.493 + public void add(int index, A element) {
1.494 + throw new UnsupportedOperationException();
1.495 + }
1.496 +
1.497 + public A remove(int index) {
1.498 + throw new UnsupportedOperationException();
1.499 + }
1.500 +
1.501 + public int indexOf(Object o) {
1.502 + int i = 0;
1.503 + for (List<A> l = this; l.tail != null; l = l.tail, i++) {
1.504 + if (l.head == null ? o == null : l.head.equals(o))
1.505 + return i;
1.506 + }
1.507 + return -1;
1.508 + }
1.509 +
1.510 + public int lastIndexOf(Object o) {
1.511 + int last = -1;
1.512 + int i = 0;
1.513 + for (List<A> l = this; l.tail != null; l = l.tail, i++) {
1.514 + if (l.head == null ? o == null : l.head.equals(o))
1.515 + last = i;
1.516 + }
1.517 + return last;
1.518 + }
1.519 +
1.520 + public ListIterator<A> listIterator() {
1.521 + return Collections.unmodifiableList(new ArrayList<A>(this)).listIterator();
1.522 + }
1.523 +
1.524 + public ListIterator<A> listIterator(int index) {
1.525 + return Collections.unmodifiableList(new ArrayList<A>(this)).listIterator(index);
1.526 + }
1.527 +
1.528 + public java.util.List<A> subList(int fromIndex, int toIndex) {
1.529 + if (fromIndex < 0 || toIndex > size() || fromIndex > toIndex)
1.530 + throw new IllegalArgumentException();
1.531 +
1.532 + ArrayList<A> a = new ArrayList<A>(toIndex - fromIndex);
1.533 + int i = 0;
1.534 + for (List<A> l = this; l.tail != null; l = l.tail, i++) {
1.535 + if (i == toIndex)
1.536 + break;
1.537 + if (i >= fromIndex)
1.538 + a.add(l.head);
1.539 + }
1.540 +
1.541 + return Collections.unmodifiableList(a);
1.542 + }
1.543 +}
