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authorBryce McKinlay <bryce@gcc.gnu.org>2001-12-15 07:47:03 +0000
committerBryce McKinlay <bryce@gcc.gnu.org>2001-12-15 07:47:03 +0000
commitd9fd7154ec7908eff8bbbce75651eccf51064ac1 (patch)
treea0210bc88649e7cd6d847884e12a68146f35d955 /libjava/java/util/AbstractSequentialList.java
parentdef9790d51a51a78a700567bb677225a90bc854e (diff)
downloadgcc-d9fd7154ec7908eff8bbbce75651eccf51064ac1.tar.gz
Collections drop from Classpath:
2001-12-15 Bryce McKinlay <bryce@waitaki.otago.ac.nz> * java/util/BitSet.java (and): Fix off-by-one bug, don't skip part of the bitset. (andNot): Likewise. (xor): Likewise. 2001-12-15 Bryce McKinlay <bryce@waitaki.otago.ac.nz> * java/util/LinkedList.java (LinkedListItr.add): Don't skip the next entry. 2001-12-15 Eric Blake <ebb9@email.byu.edu> * java/util/TreeMap.java (removeNode): Fix bug in node removal. 2001-12-15 Bryce McKinlay <bryce@waitaki.otago.ac.nz> * java/util/AbstractCollection.java (containsAll): Use size of the correct collection for loop bound. * java/util/AbstractList.java (iterator.next): Increment pos after calling get on backing list. (listIterator.next): Likewise. * java/util/LinkedList.java (addLastEntry): Don't increment size before checking for size == 0. (addFirstEntry): Rearrange to match addLastEntry. (add): Do not increment size before inserting the new entry. * java/util/AbstractCollection.java (addAll): Use size of the correct collection for loop bound. 2001-12-15 Bryce McKinlay <bryce@waitaki.otago.ac.nz> * java/util/AbstractSet.java (removeAll): Fix scoping thinko. * java/util/HashMap.java (putAllInternal): Set size here. * java/util/Hashtable.java (putAllInternal): New method. Copy contents of a map efficiently without calling put() or putAll(). (Hashtable (map)): Use putAllInternal. (clone): Likewise. 2001-12-15 Eric Blake <ebb9@email.byu.edu> * java/util/Collections.java: * java/util/Vector.java: * java/util/WeakHashMap.java: Fix spelling errors. 2001-12-15 Eric Blake <ebb9@email.byu.edu> * java/util/AbstractCollection.java (removeAllInternal), (retainAllInternal): Add hooks for use by ArrayList. * java/util/AbstractList.java: Minor code updates. Fix some scoping. * java/util/AbstractMap.java: ditto * java/util/ArrayList.java (readObject, writeObject): ditto (removeAllInternal, retainAllInternal): Optimize. * java/util/Arrays.java: ditto * java/util/Collections.java: ditto. Change order of parameters to equals(Object, Object) to match specs. * java/util/Dictionary.java: Improve javadoc. (Dictionary): Add explicit constructor. * java/util/HashMap.java: Improve javadoc. Rearrange methods to follow order in JDK. Cleanups related to recent code migration to AbstractMap. Fix some scoping. (entrySet): Cache the result. (modCount): Ensure that this is updated correctly. * java/util/HashSet.java: Improve javadoc. Fix some scoping. (init): Add hooks for LinkedHashSet. (map): Use "" instead of Boolean.TRUE in backing map. Use package-private API where possible for less overhead. (readObject, writeObject): Fix serialization. * java/util/Hashtable.java: Improve javadoc. Fix some scoping. (entrySet, keySet, values): Cache the result. (modCount): Ensure that this is updated correctly. (contains, remove): Fix NullPointer checking to match specs. (class Enumeration): Make more like HashIterator. * java/util/IdentityHashMap.java: Minor code updates. (modCount): Ensure that this is updated correctly. (readObject, writeObject): Fix serialization. * java/util/LinkedHashMap.java: Minor code updates. Cleanups related to recent code migration to AbstractMap. * java/util/LinkedHashSet.java: New file. * java/util/LinkedList.java: (readObject, writeObject): Fix serialization. * java/util/Makefile.am: List recently added files. * java/util/Stack.java: Minor code updates. * java/util/TreeMap.java: Improve javadoc. Overhaul the class to be more efficient. Fix some scoping. Rearrange the methods. (nil): Ensure that this can be thread-safe, and make it a static final. Initialize it to be more useful as a sentinal node. (Node): Specify color in constructor. (deleteFixup, insertFixup): Improve comments and algorithm. (fabricateTree): Redesign with less overhead. (lowestGreaterThan): Add parameter first to make SubMap easier. (removeNode): Patch hole where nil was being modified. Choose predecessor instead of successor so in-place swap works. (class VerifyResult, verifyTree, verifySub, verifyError): Remove this dead code after verifying the class works. (class SubMap): Rewrite several algorithms to avoid problems with comparing nil. * java/util/TreeSet.java: Improve javadoc. Fix some scoping. (clone): Fix ClassCastException when cloning subSet(). (readObject, writeObject): Fix serialization. * java/util/WeakHashMap.java: Improve javadoc. Fix some scoping. (NULL_KEY): Make it compare as null, for ease elsewhere. (Class WeakEntry): Rename from Entry, to avoid shadowing Map.Entry. Add missing toString. (modCount): Ensure that this is updated correctly. (clear, containsValue, keySet, putAll, values, WeakHashMap(Map)): Add missing methods and constructor. 2001-12-15 Eric Blake <ebb9@email.byu.edu> * java/util/ArrayList.java (checkBoundExclusive), (checkBoundInclusive): Rename from range??clusive, to match AbstractList. * java/util/LinkedList.java (checkBoundsExclusive), (checkBoundsInclusive): ditto * java/util/Vector.java (checkBoundExclusive), (checkBoundInclusive): Move bounds checking into common methods. 2001-12-15 Eric Blake <ebb9@email.byu.edu> * java/util/AbstractList.java: (modCount): Make sure it is updated in all needed places. * java/util/ArrayList.java: Improve javadoc. Implements RandomAccess. Add serialVersionUID. Reorder methods. (modCount): Make sure it is updated in all needed places. (rangeExclusive, rangeInclusive): Add common methods for bounds check. (isEmpty): Add missing method. * java/util/Collections.java: (class SynchronizedList): Make package visible. * java/util/ConcurrentModificationException.java: Improve javadoc. * java/util/EmptyStackException.java: Improve javadoc. * java/util/LinkedList.java: Improve javadoc. (modCount): Make sure it is updated in all needed places. (rangeExclusive, rangeInclusive): Add common methods for bounds check. * java/util/NoSuchElementException.java: Improve javadoc. * java/util/Stack.java: Improve javadoc. Fix synchronization issues. (modCount): Make sure it is updated in all needed places. * java/util/Vector.java: Improve javadoc. Fix synchronization issues. Implements RandomAccess. Reorder methods. (modCount): Make sure it is updated in all needed places. (setSize): Fix according to specifications: this does not dictate the backing array size. (removeAll, retainAll): Faster implementations. 2001-12-15 Eric Blake <ebb9@email.byu.edu> * java/util/BitSet.java: Improve javadoc. (cardinality(), clear(), clear(int, int), flip(int)), (flip(int, int), get(int, int), intersects(BitSet), isEmpty()), (nextClearBit(int), nextSetBit(int), set(int, boolean)), (set(int, int), set(int, int, boolean)): Add new JDK 1.4 methods. (clone): Fix so subclasses clone correctly. 2001-12-15 Eric Blake <ebb9@email.byu.edu> * java/util/AbstractCollection.java: Improve javadoc. (AbstractCollection()): Make constructor protected. (equals(Object, Object), hashCode(Object)): Add utility methods. * java/util/AbstractList.java: Improve javadoc. (AbstractList()): Make constructor protected. (indexOf(Object)): Call listIterator(), not listIterator(int). (iterator()): Follow Sun's requirement to not use listIterator(0). (listIterator(int)): Make AbstractListItr anonymous. (subList(int, int)): Add support for RandomAccess. (SubList.add(int, Object), SubList.remove(Object)): Fix bug with modCount tracking. (SubList.addAll(Collection)): Add missing method. (SubList.listIterator(int)): Fix bugs in indexing, modCount tracking. (class RandomAccessSubList): Add new class. * java/util/AbstractMap.java: Improve javadoc. (keys, values, KEYS, VALUES, ENTRIES): Consolidate common map fields. (AbstractMap()): Make constructor protected. (equals(Object, Object), hashCode(Object)): Add utility methods. (equals(Object)): Change algorithm to entrySet().equals(m.entrySet()), as documented by Sun. (keySet(), values()): Cache the collections. * java/util/AbstractSequentialList.java: Improve javadoc. (AbstractSequentialList()): Make constructor protected. * java/util/AbstractSet.java: Improve javadoc. (AbstractSet()): Make constructor protected. (removeAll(Collection)): Add missing method. * java/util/Arrays.java: Improve javadoc, rearrange method orders. (defaultComparator): Remove, in favor of Collections.compare(Object, Object, Comparator). (binarySearch, equals, sort): Fix natural order comparison of floats and doubles. Also improve Object comparison - when comparator is null, use natural order. (fill, sort): Add missing checks for IllegalArgumentException. (sort, qsort): Fix sorting bugs, rework the code for more legibility. (mergeSort): Inline into sort(Object[], int, int, Comparator). (class ArrayList): Rename from ListImpl, and make compatible with JDK serialization. Add methods which more efficiently override those of AbstractList. * java/util/Collections: Improve javadoc. (isSequential(List)): Add and use a method for deciding between RandomAccess and sequential algorithms on lists. (class Empty*, class Synchronized*, class Unmodifiable*): Make compliant with JDK serializability. (class Singleton*, class CopiesList, class RevereseComparator), (class UnmodifiableMap.UnmodifiableEntrySet), (class *RandomAccessList): New classes for serial compatibility. (class Empty*, class Singleton*, class CopiesList): Add methods which more efficiently override those of Abstract*. (search): Inline into binarySearch(List, Object, Comparator). (binarySearch): Make sequential search only do log(n) comparisons, instead of n. (copy(List, List)): Do bounds checking before starting. (indexOfSubList, lastIndexOfSubList, list, replaceAll, rotate), (swap): Add new JDK 1.4 methods. (binarySearch, max, min, sort): Allow null comparator to represent natural ordering. (reverse(List)): Avoid unnecessary swap. (shuffle(List, Random)): Do shuffle in-place for RandomAccess lists. (SingletonList.get): Fix logic bug. (SingletonMap.entrySet): Make the entry immutable, and cache the returned set. (SynchronizedCollection, SynchronizedMap, UnmodifiableCollection), (UnmodifiableMap): Detect null pointer in construction. (SynchronizedMap, UnmodifiableMap): Cache collection views. * java/util/BasicMapEntry: Improve javadoc. From-SVN: r48035
Diffstat (limited to 'libjava/java/util/AbstractSequentialList.java')
-rw-r--r--libjava/java/util/AbstractSequentialList.java176
1 files changed, 134 insertions, 42 deletions
diff --git a/libjava/java/util/AbstractSequentialList.java b/libjava/java/util/AbstractSequentialList.java
index 81481be0466..2267b02e523 100644
--- a/libjava/java/util/AbstractSequentialList.java
+++ b/libjava/java/util/AbstractSequentialList.java
@@ -1,5 +1,5 @@
/* AbstractSequentialList.java -- List implementation for sequential access
- Copyright (C) 1998, 1999, 2000 Free Software Foundation, Inc.
+ Copyright (C) 1998, 1999, 2000, 2001 Free Software Foundation, Inc.
This file is part of GNU Classpath.
@@ -25,100 +25,192 @@ This exception does not however invalidate any other reasons why the
executable file might be covered by the GNU General Public License. */
-// TO DO:
-// ~ Lots of doc comments still missing.
-// ~ The class comment should include a description of what should be overridden
-// to provide what features, as should the listIterator comment.
-
package java.util;
/**
* Abstract superclass to make it easier to implement the List interface when
- * backed by a sequential-access store, such as a linked list.
+ * backed by a sequential-access store, such as a linked list. For random
+ * access data, use AbstractList. This class implements the random access
+ * methods (<code>get</code>, <code>set</code>, <code>add</code>, and
+ * <code>remove</code>) atop the list iterator, opposite of AbstractList's
+ * approach of implementing the iterator atop random access.
+ * <p>
+ *
+ * To implement a list, you need an implementation for <code>size()</code>
+ * and <code>listIterator</code>. With just <code>hasNext</code>,
+ * <code>next</code>, <code>hasPrevious</code>, <code>previous</code>,
+ * <code>nextIndex</code>, and <code>previousIndex</code>, you have an
+ * unmodifiable list. For a modifiable one, add <code>set</code>, and for
+ * a variable-size list, add <code>add</code> and <code>remove</code>.
+ * <p>
+ *
+ * The programmer should provide a no-argument constructor, and one that
+ * accepts another Collection, as recommended by the Collection interface.
+ * Unfortunately, there is no way to enforce this in Java.
+ *
+ * @author Original author unknown
+ * @author Bryce McKinlay
+ * @author Eric Blake <ebb9@email.byu.edu>
+ * @see Collection
+ * @see List
+ * @see AbstractList
+ * @see AbstractCollection
+ * @see ListIterator
+ * @see LinkedList
+ * @since 1.2
+ * @status updated to 1.4
*/
public abstract class AbstractSequentialList extends AbstractList
{
/**
+ * The main constructor, for use by subclasses.
+ */
+ protected AbstractSequentialList()
+ {
+ }
+
+ /**
* Returns a ListIterator over the list, starting from position index.
* Subclasses must provide an implementation of this method.
*
- * @exception IndexOutOfBoundsException if index < 0 || index > size()
+ * @param index the starting position of the list
+ * @return the list iterator
+ * @throws IndexOutOfBoundsException if index &lt; 0 || index &gt; size()
*/
public abstract ListIterator listIterator(int index);
/**
- * Add an element to the list at a given index. This implementation obtains a
- * ListIterator positioned at the specified index, and then adds the element
- * using the ListIterator's add method.
+ * Insert an element into the list at a given position (optional operation).
+ * This shifts all existing elements from that position to the end one
+ * index to the right. This version of add has no return, since it is
+ * assumed to always succeed if there is no exception. This iteration
+ * uses listIterator(index).add(o).
*
- * @param index the position to add the element
- * @param o the element to insert
- * @exception IndexOutOfBoundsException if index < 0 || index > size()
- * @exception UnsupportedOperationException if the iterator returned by
- * listIterator(index) does not support the add method.
+ * @param index the location to insert the item
+ * @param o the object to insert
+ * @throws UnsupportedOperationException if this list does not support the
+ * add operation
+ * @throws IndexOutOfBoundsException if index &lt; 0 || index &gt; size()
+ * @throws ClassCastException if o cannot be added to this list due to its
+ * type
+ * @throws IllegalArgumentException if o cannot be added to this list for
+ * some other reason
*/
public void add(int index, Object o)
{
- ListIterator i = listIterator(index);
- i.add(o);
+ listIterator(index).add(o);
}
/**
- * @specnote The spec in the JDK1.3 online docs is wrong. The implementation
- * should not call next() to skip over new elements as they are
- * added, because iterator.add() should add new elements BEFORE
- * the cursor.
+ * Insert the contents of a collection into the list at a given position
+ * (optional operation). Shift all elements at that position to the right
+ * by the number of elements inserted. This operation is undefined if
+ * this list is modified during the operation (for example, if you try
+ * to insert a list into itself).
+ * <p>
+ *
+ * This implementation grabs listIterator(index), then proceeds to use add
+ * for each element returned by c's iterator. Sun's online specs are wrong,
+ * claiming that this also calls next(): listIterator.add() correctly
+ * skips the added element.
+ *
+ * @param index the location to insert the collection
+ * @param c the collection to insert
+ * @return true if the list was modified by this action, that is, if c is
+ * non-empty
+ * @throws UnsupportedOperationException if this list does not support the
+ * addAll operation
+ * @throws IndexOutOfBoundsException if index &lt; 0 || index &gt; size()
+ * @throws ClassCastException if some element of c cannot be added to this
+ * list due to its type
+ * @throws IllegalArgumentException if some element of c cannot be added
+ * to this list for some other reason
+ * @throws NullPointerException if the specified collection is null
+ * @see #add(int, Object)
*/
public boolean addAll(int index, Collection c)
{
- boolean modified = false;
Iterator ci = c.iterator();
int size = c.size();
ListIterator i = listIterator(index);
- for (int pos = 0; pos < size; pos++)
- {
- i.add(ci.next());
- }
- return (size > 0);
+ for (int pos = size; pos > 0; pos--)
+ i.add(ci.next());
+ return size > 0;
}
+ /**
+ * Get the element at a given index in this list. This implementation
+ * returns listIterator(index).next().
+ *
+ * @param index the index of the element to be returned
+ * @return the element at index index in this list
+ * @throws IndexOutOfBoundsException if index &lt; 0 || index &gt;= size()
+ */
public Object get(int index)
{
- ListIterator i = listIterator(index);
- if (index < 0 || index > size())
- throw new IndexOutOfBoundsException("Index: " + index + ", Size:" +
- size());
- return i.next();
+ // This is a legal listIterator position, but an illegal get.
+ if (index == size())
+ throw new IndexOutOfBoundsException("Index: " + index + ", Size:"
+ + size());
+ return listIterator(index).next();
}
/**
- * Return an Iterator over this List. This implementation returns
- * listIterator().
+ * Obtain an Iterator over this list, whose sequence is the list order. This
+ * implementation returns listIterator().
*
- * @return an Iterator over this List
+ * @return an Iterator over the elements of this list, in order
*/
public Iterator iterator()
{
return listIterator();
}
+ /**
+ * Remove the element at a given position in this list (optional operation).
+ * Shifts all remaining elements to the left to fill the gap. This
+ * implementation uses listIterator(index) and ListIterator.remove().
+ *
+ * @param index the position within the list of the object to remove
+ * @return the object that was removed
+ * @throws UnsupportedOperationException if this list does not support the
+ * remove operation
+ * @throws IndexOutOfBoundsException if index &lt; 0 || index &gt;= size()
+ */
public Object remove(int index)
{
+ // This is a legal listIterator position, but an illegal remove.
+ if (index == size())
+ throw new IndexOutOfBoundsException("Index: " + index + ", Size:"
+ + size());
ListIterator i = listIterator(index);
- if (index < 0 || index > size())
- throw new IndexOutOfBoundsException("Index: " + index + ", Size:" +
- size());
Object removed = i.next();
i.remove();
return removed;
}
+ /**
+ * Replace an element of this list with another object (optional operation).
+ * This implementation uses listIterator(index) and ListIterator.set(o).
+ *
+ * @param index the position within this list of the element to be replaced
+ * @param o the object to replace it with
+ * @return the object that was replaced
+ * @throws UnsupportedOperationException if this list does not support the
+ * set operation
+ * @throws IndexOutOfBoundsException if index &lt; 0 || index &gt;= size()
+ * @throws ClassCastException if o cannot be added to this list due to its
+ * type
+ * @throws IllegalArgumentException if o cannot be added to this list for
+ * some other reason
+ */
public Object set(int index, Object o)
{
+ // This is a legal listIterator position, but an illegal set.
+ if (index == size())
+ throw new IndexOutOfBoundsException("Index: " + index + ", Size:"
+ + size());
ListIterator i = listIterator(index);
- if (index < 0 || index > size())
- throw new IndexOutOfBoundsException("Index: " + index + ", Size:" +
- size());
Object old = i.next();
i.set(o);
return old;