--- jsr166/src/main/java/util/Vector.java 2006/06/26 00:17:48 1.17
+++ jsr166/src/main/java/util/Vector.java 2008/05/19 00:28:21 1.25
@@ -1,8 +1,26 @@
/*
- * %W% %E%
+ * Copyright 1994-2007 Sun Microsystems, Inc. All Rights Reserved.
+ * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
*
- * Copyright 2006 Sun Microsystems, Inc. All rights reserved.
- * SUN PROPRIETARY/CONFIDENTIAL. Use is subject to license terms.
+ * 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. Sun designates this
+ * particular file as subject to the "Classpath" exception as provided
+ * by Sun 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 Sun Microsystems, Inc., 4150 Network Circle, Santa Clara,
+ * CA 95054 USA or visit www.sun.com if you need additional information or
+ * have any questions.
*/
package java.util;
@@ -23,15 +41,18 @@ package java.util;
* capacity of a vector before inserting a large number of
* components; this reduces the amount of incremental reallocation.
*
- * The Iterators returned by Vector's iterator and listIterator
- * methods are fail-fast: if the Vector is structurally modified
- * at any time after the Iterator is created, in any way except through the
- * Iterator's own remove or add methods, the Iterator will throw a
- * ConcurrentModificationException. Thus, in the face of concurrent
- * modification, the Iterator fails quickly and cleanly, rather than risking
- * arbitrary, non-deterministic behavior at an undetermined time in the future.
- * The Enumerations returned by Vector's elements method are not
- * fail-fast.
+ *
+ * The iterators returned by this class's {@link #iterator() iterator} and
+ * {@link #listIterator(int) listIterator} methods are fail-fast:
+ * if the vector is structurally modified at any time after the iterator is
+ * created, in any way except through the iterator's own
+ * {@link ListIterator#remove() remove} or
+ * {@link ListIterator#add(Object) add} methods, the iterator will throw a
+ * {@link ConcurrentModificationException}. Thus, in the face of
+ * concurrent modification, the iterator fails quickly and cleanly, rather
+ * than risking arbitrary, non-deterministic behavior at an undetermined
+ * time in the future. The {@link Enumeration Enumerations} returned by
+ * the {@link #elements() elements} method are not fail-fast.
*
*
Note that the fail-fast behavior of an iterator cannot be guaranteed
* as it is, generally speaking, impossible to make any hard guarantees in the
@@ -43,16 +64,15 @@ package java.util;
*
*
As of the Java 2 platform v1.2, this class was retrofitted to
* implement the {@link List} interface, making it a member of the
- * Java
- * Collections Framework. Unlike the new collection
- * implementations, {@code Vector} is synchronized.
+ *
+ * Java Collections Framework. Unlike the new collection
+ * implementations, {@code Vector} is synchronized. If a thread-safe
+ * implementation is not needed, it is recommended to use {@link
+ * ArrayList} in place of {@code Vector}.
*
* @author Lee Boynton
* @author Jonathan Payne
- * @version %I%, %G%
* @see Collection
- * @see List
- * @see ArrayList
* @see LinkedList
* @since JDK1.0
*/
@@ -104,12 +124,12 @@ public class Vector
* is negative
*/
public Vector(int initialCapacity, int capacityIncrement) {
- super();
+ super();
if (initialCapacity < 0)
throw new IllegalArgumentException("Illegal Capacity: "+
initialCapacity);
- this.elementData = new Object[initialCapacity];
- this.capacityIncrement = capacityIncrement;
+ this.elementData = new Object[initialCapacity];
+ this.capacityIncrement = capacityIncrement;
}
/**
@@ -121,7 +141,7 @@ public class Vector
* is negative
*/
public Vector(int initialCapacity) {
- this(initialCapacity, 0);
+ this(initialCapacity, 0);
}
/**
@@ -130,7 +150,7 @@ public class Vector
* zero.
*/
public Vector() {
- this(10);
+ this(10);
}
/**
@@ -144,11 +164,11 @@ public class Vector
* @since 1.2
*/
public Vector(Collection c) {
- elementData = c.toArray();
- elementCount = elementData.length;
- // c.toArray might (incorrectly) not return Object[] (see 6260652)
- if (elementData.getClass() != Object[].class)
- elementData = Arrays.copyOf(elementData, elementCount, Object[].class);
+ elementData = c.toArray();
+ elementCount = elementData.length;
+ // c.toArray might (incorrectly) not return Object[] (see 6260652)
+ if (elementData.getClass() != Object[].class)
+ elementData = Arrays.copyOf(elementData, elementCount, Object[].class);
}
/**
@@ -165,7 +185,7 @@ public class Vector
* @see #toArray(Object[])
*/
public synchronized void copyInto(Object[] anArray) {
- System.arraycopy(elementData, 0, anArray, 0, elementCount);
+ System.arraycopy(elementData, 0, anArray, 0, elementCount);
}
/**
@@ -177,11 +197,11 @@ public class Vector
* minimize the storage of a vector.
*/
public synchronized void trimToSize() {
- modCount++;
- int oldCapacity = elementData.length;
- if (elementCount < oldCapacity) {
+ modCount++;
+ int oldCapacity = elementData.length;
+ if (elementCount < oldCapacity) {
elementData = Arrays.copyOf(elementData, elementCount);
- }
+ }
}
/**
@@ -202,8 +222,8 @@ public class Vector
* @param minCapacity the desired minimum capacity
*/
public synchronized void ensureCapacity(int minCapacity) {
- modCount++;
- ensureCapacityHelper(minCapacity);
+ modCount++;
+ ensureCapacityHelper(minCapacity);
}
/**
@@ -215,16 +235,16 @@ public class Vector
* @see #ensureCapacity(int)
*/
private void ensureCapacityHelper(int minCapacity) {
- int oldCapacity = elementData.length;
- if (minCapacity > oldCapacity) {
- Object[] oldData = elementData;
- int newCapacity = (capacityIncrement > 0) ?
- (oldCapacity + capacityIncrement) : (oldCapacity * 2);
- if (newCapacity < minCapacity) {
- newCapacity = minCapacity;
- }
+ int oldCapacity = elementData.length;
+ if (minCapacity > oldCapacity) {
+ Object[] oldData = elementData;
+ int newCapacity = (capacityIncrement > 0) ?
+ (oldCapacity + capacityIncrement) : (oldCapacity * 2);
+ if (newCapacity < minCapacity) {
+ newCapacity = minCapacity;
+ }
elementData = Arrays.copyOf(elementData, newCapacity);
- }
+ }
}
/**
@@ -237,15 +257,15 @@ public class Vector
* @throws ArrayIndexOutOfBoundsException if the new size is negative
*/
public synchronized void setSize(int newSize) {
- modCount++;
- if (newSize > elementCount) {
- ensureCapacityHelper(newSize);
- } else {
- for (int i = newSize ; i < elementCount ; i++) {
- elementData[i] = null;
- }
- }
- elementCount = newSize;
+ modCount++;
+ if (newSize > elementCount) {
+ ensureCapacityHelper(newSize);
+ } else {
+ for (int i = newSize ; i < elementCount ; i++) {
+ elementData[i] = null;
+ }
+ }
+ elementCount = newSize;
}
/**
@@ -256,7 +276,7 @@ public class Vector
* of this vector)
*/
public synchronized int capacity() {
- return elementData.length;
+ return elementData.length;
}
/**
@@ -265,7 +285,7 @@ public class Vector
* @return the number of components in this vector
*/
public synchronized int size() {
- return elementCount;
+ return elementCount;
}
/**
@@ -276,7 +296,7 @@ public class Vector
* {@code false} otherwise.
*/
public synchronized boolean isEmpty() {
- return elementCount == 0;
+ return elementCount == 0;
}
/**
@@ -289,22 +309,22 @@ public class Vector
* @see Iterator
*/
public Enumeration elements() {
- return new Enumeration() {
- int count = 0;
+ return new Enumeration() {
+ int count = 0;
+
+ public boolean hasMoreElements() {
+ return count < elementCount;
+ }
- public boolean hasMoreElements() {
- return count < elementCount;
- }
-
- public E nextElement() {
- synchronized (Vector.this) {
- if (count < elementCount) {
- return (E)elementData[count++];
- }
- }
- throw new NoSuchElementException("Vector Enumeration");
- }
- };
+ public E nextElement() {
+ synchronized (Vector.this) {
+ if (count < elementCount) {
+ return elementData(count++);
+ }
+ }
+ throw new NoSuchElementException("Vector Enumeration");
+ }
+ };
}
/**
@@ -317,7 +337,7 @@ public class Vector
* @return {@code true} if this vector contains the specified element
*/
public boolean contains(Object o) {
- return indexOf(o, 0) >= 0;
+ return indexOf(o, 0) >= 0;
}
/**
@@ -332,7 +352,7 @@ public class Vector
* this vector, or -1 if this vector does not contain the element
*/
public int indexOf(Object o) {
- return indexOf(o, 0);
+ return indexOf(o, 0);
}
/**
@@ -352,16 +372,16 @@ public class Vector
* @see Object#equals(Object)
*/
public synchronized int indexOf(Object o, int index) {
- if (o == null) {
- for (int i = index ; i < elementCount ; i++)
- if (elementData[i]==null)
- return i;
- } else {
- for (int i = index ; i < elementCount ; i++)
- if (o.equals(elementData[i]))
- return i;
- }
- return -1;
+ if (o == null) {
+ for (int i = index ; i < elementCount ; i++)
+ if (elementData[i]==null)
+ return i;
+ } else {
+ for (int i = index ; i < elementCount ; i++)
+ if (o.equals(elementData[i]))
+ return i;
+ }
+ return -1;
}
/**
@@ -376,7 +396,7 @@ public class Vector
* this vector, or -1 if this vector does not contain the element
*/
public synchronized int lastIndexOf(Object o) {
- return lastIndexOf(o, elementCount-1);
+ return lastIndexOf(o, elementCount-1);
}
/**
@@ -399,16 +419,16 @@ public class Vector
if (index >= elementCount)
throw new IndexOutOfBoundsException(index + " >= "+ elementCount);
- if (o == null) {
- for (int i = index; i >= 0; i--)
- if (elementData[i]==null)
- return i;
- } else {
- for (int i = index; i >= 0; i--)
- if (o.equals(elementData[i]))
- return i;
- }
- return -1;
+ if (o == null) {
+ for (int i = index; i >= 0; i--)
+ if (elementData[i]==null)
+ return i;
+ } else {
+ for (int i = index; i >= 0; i--)
+ if (o.equals(elementData[i]))
+ return i;
+ }
+ return -1;
}
/**
@@ -420,14 +440,14 @@ public class Vector
* @param index an index into this vector
* @return the component at the specified index
* @throws ArrayIndexOutOfBoundsException if the index is out of range
- * ({@code index < 0 || index >= size()})
+ * ({@code index < 0 || index >= size()})
*/
public synchronized E elementAt(int index) {
- if (index >= elementCount) {
- throw new ArrayIndexOutOfBoundsException(index + " >= " + elementCount);
- }
+ if (index >= elementCount) {
+ throw new ArrayIndexOutOfBoundsException(index + " >= " + elementCount);
+ }
- return (E)elementData[index];
+ return elementData(index);
}
/**
@@ -438,10 +458,10 @@ public class Vector
* @throws NoSuchElementException if this vector has no components
*/
public synchronized E firstElement() {
- if (elementCount == 0) {
- throw new NoSuchElementException();
- }
- return (E)elementData[0];
+ if (elementCount == 0) {
+ throw new NoSuchElementException();
+ }
+ return elementData(0);
}
/**
@@ -452,10 +472,10 @@ public class Vector
* @throws NoSuchElementException if this vector is empty
*/
public synchronized E lastElement() {
- if (elementCount == 0) {
- throw new NoSuchElementException();
- }
- return (E)elementData[elementCount - 1];
+ if (elementCount == 0) {
+ throw new NoSuchElementException();
+ }
+ return elementData(elementCount - 1);
}
/**
@@ -476,14 +496,14 @@ public class Vector
* @param obj what the component is to be set to
* @param index the specified index
* @throws ArrayIndexOutOfBoundsException if the index is out of range
- * ({@code index < 0 || index >= size()})
+ * ({@code index < 0 || index >= size()})
*/
public synchronized void setElementAt(E obj, int index) {
- if (index >= elementCount) {
- throw new ArrayIndexOutOfBoundsException(index + " >= " +
- elementCount);
- }
- elementData[index] = obj;
+ if (index >= elementCount) {
+ throw new ArrayIndexOutOfBoundsException(index + " >= " +
+ elementCount);
+ }
+ elementData[index] = obj;
}
/**
@@ -503,23 +523,23 @@ public class Vector
*
* @param index the index of the object to remove
* @throws ArrayIndexOutOfBoundsException if the index is out of range
- * ({@code index < 0 || index >= size()})
+ * ({@code index < 0 || index >= size()})
*/
public synchronized void removeElementAt(int index) {
- modCount++;
- if (index >= elementCount) {
- throw new ArrayIndexOutOfBoundsException(index + " >= " +
- elementCount);
- }
- else if (index < 0) {
- throw new ArrayIndexOutOfBoundsException(index);
- }
- int j = elementCount - index - 1;
- if (j > 0) {
- System.arraycopy(elementData, index + 1, elementData, index, j);
- }
- elementCount--;
- elementData[elementCount] = null; /* to let gc do its work */
+ modCount++;
+ if (index >= elementCount) {
+ throw new ArrayIndexOutOfBoundsException(index + " >= " +
+ elementCount);
+ }
+ else if (index < 0) {
+ throw new ArrayIndexOutOfBoundsException(index);
+ }
+ int j = elementCount - index - 1;
+ if (j > 0) {
+ System.arraycopy(elementData, index + 1, elementData, index, j);
+ }
+ elementCount--;
+ elementData[elementCount] = null; /* to let gc do its work */
}
/**
@@ -543,18 +563,18 @@ public class Vector
* @param obj the component to insert
* @param index where to insert the new component
* @throws ArrayIndexOutOfBoundsException if the index is out of range
- * ({@code index < 0 || index > size()})
+ * ({@code index < 0 || index > size()})
*/
public synchronized void insertElementAt(E obj, int index) {
- modCount++;
- if (index > elementCount) {
- throw new ArrayIndexOutOfBoundsException(index
- + " > " + elementCount);
- }
- ensureCapacityHelper(elementCount + 1);
- System.arraycopy(elementData, index, elementData, index + 1, elementCount - index);
- elementData[index] = obj;
- elementCount++;
+ modCount++;
+ if (index > elementCount) {
+ throw new ArrayIndexOutOfBoundsException(index
+ + " > " + elementCount);
+ }
+ ensureCapacityHelper(elementCount + 1);
+ System.arraycopy(elementData, index, elementData, index + 1, elementCount - index);
+ elementData[index] = obj;
+ elementCount++;
}
/**
@@ -563,15 +583,15 @@ public class Vector
* increased if its size becomes greater than its capacity.
*
* This method is identical in functionality to the
- * {@link #remove(Object)} method (which is part of the
- * {@link List} interface).
+ * {@link #add(Object) add(E)}
+ * method (which is part of the {@link List} interface).
*
* @param obj the component to be added
*/
public synchronized void addElement(E obj) {
- modCount++;
- ensureCapacityHelper(elementCount + 1);
- elementData[elementCount++] = obj;
+ modCount++;
+ ensureCapacityHelper(elementCount + 1);
+ elementData[elementCount++] = obj;
}
/**
@@ -581,23 +601,22 @@ public class Vector
* object's index is shifted downward to have an index one smaller
* than the value it had previously.
*
- * This method is identical in functionality to the remove(Object)
- * method (which is part of the List interface).
+ *
This method is identical in functionality to the
+ * {@link #remove(Object)} method (which is part of the
+ * {@link List} interface).
*
* @param obj the component to be removed
* @return {@code true} if the argument was a component of this
* vector; {@code false} otherwise.
- * @see List#remove(Object)
- * @see List
*/
public synchronized boolean removeElement(Object obj) {
- modCount++;
- int i = indexOf(obj);
- if (i >= 0) {
- removeElementAt(i);
- return true;
- }
- return false;
+ modCount++;
+ int i = indexOf(obj);
+ if (i >= 0) {
+ removeElementAt(i);
+ return true;
+ }
+ return false;
}
/**
@@ -608,11 +627,11 @@ public class Vector
*/
public synchronized void removeAllElements() {
modCount++;
- // Let gc do its work
- for (int i = 0; i < elementCount; i++)
- elementData[i] = null;
+ // Let gc do its work
+ for (int i = 0; i < elementCount; i++)
+ elementData[i] = null;
- elementCount = 0;
+ elementCount = 0;
}
/**
@@ -623,15 +642,16 @@ public class Vector
* @return a clone of this vector
*/
public synchronized Object clone() {
- try {
- Vector v = (Vector) super.clone();
- v.elementData = Arrays.copyOf(elementData, elementCount);
- v.modCount = 0;
- return v;
- } catch (CloneNotSupportedException e) {
- // this shouldn't happen, since we are Cloneable
- throw new InternalError();
- }
+ try {
+ @SuppressWarnings("unchecked")
+ Vector v = (Vector) super.clone();
+ v.elementData = Arrays.copyOf(elementData, elementCount);
+ v.modCount = 0;
+ return v;
+ } catch (CloneNotSupportedException e) {
+ // this shouldn't happen, since we are Cloneable
+ throw new InternalError();
+ }
}
/**
@@ -659,19 +679,20 @@ public class Vector
* does not contain any null elements.)
*
* @param a the array into which the elements of the Vector are to
- * be stored, if it is big enough; otherwise, a new array of the
- * same runtime type is allocated for this purpose.
+ * 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 the Vector
* @throws ArrayStoreException if the runtime type of a is not a supertype
* of the runtime type of every element in this Vector
* @throws NullPointerException if the given array is null
* @since 1.2
*/
+ @SuppressWarnings("unchecked")
public synchronized T[] toArray(T[] a) {
if (a.length < elementCount)
return (T[]) Arrays.copyOf(elementData, elementCount, a.getClass());
- System.arraycopy(elementData, 0, a, 0, elementCount);
+ System.arraycopy(elementData, 0, a, 0, elementCount);
if (a.length > elementCount)
a[elementCount] = null;
@@ -681,6 +702,11 @@ public class Vector
// Positional Access Operations
+ @SuppressWarnings("unchecked")
+ E elementData(int index) {
+ return (E) elementData[index];
+ }
+
/**
* Returns the element at the specified position in this Vector.
*
@@ -691,10 +717,10 @@ public class Vector
* @since 1.2
*/
public synchronized E get(int index) {
- if (index >= elementCount)
- throw new ArrayIndexOutOfBoundsException(index);
+ if (index >= elementCount)
+ throw new ArrayIndexOutOfBoundsException(index);
- return (E)elementData[index];
+ return elementData(index);
}
/**
@@ -705,16 +731,16 @@ public class Vector
* @param element element to be stored at the specified position
* @return the element previously at the specified position
* @throws ArrayIndexOutOfBoundsException if the index is out of range
- * ({@code index < 0 || index >= size()})
+ * ({@code index < 0 || index >= size()})
* @since 1.2
*/
public synchronized E set(int index, E element) {
- if (index >= elementCount)
- throw new ArrayIndexOutOfBoundsException(index);
+ if (index >= elementCount)
+ throw new ArrayIndexOutOfBoundsException(index);
- Object oldValue = elementData[index];
- elementData[index] = element;
- return (E)oldValue;
+ E oldValue = elementData(index);
+ elementData[index] = element;
+ return oldValue;
}
/**
@@ -725,9 +751,9 @@ public class Vector
* @since 1.2
*/
public synchronized boolean add(E e) {
- modCount++;
- ensureCapacityHelper(elementCount + 1);
- elementData[elementCount++] = e;
+ modCount++;
+ ensureCapacityHelper(elementCount + 1);
+ elementData[elementCount++] = e;
return true;
}
@@ -766,25 +792,25 @@ public class Vector
* Shifts any subsequent elements to the left (subtracts one from their
* indices). Returns the element that was removed from the Vector.
*
- * @exception ArrayIndexOutOfBoundsException index out of range (index
- * < 0 || index >= size())
+ * @throws ArrayIndexOutOfBoundsException if the index is out of range
+ * ({@code index < 0 || index >= size()})
* @param index the index of the element to be removed
* @return element that was removed
* @since 1.2
*/
public synchronized E remove(int index) {
- modCount++;
- if (index >= elementCount)
- throw new ArrayIndexOutOfBoundsException(index);
- Object oldValue = elementData[index];
-
- int numMoved = elementCount - index - 1;
- if (numMoved > 0)
- System.arraycopy(elementData, index+1, elementData, index,
- numMoved);
- elementData[--elementCount] = null; // Let gc do its work
+ modCount++;
+ if (index >= elementCount)
+ throw new ArrayIndexOutOfBoundsException(index);
+ E oldValue = elementData(index);
+
+ int numMoved = elementCount - index - 1;
+ if (numMoved > 0)
+ System.arraycopy(elementData, index+1, elementData, index,
+ numMoved);
+ elementData[--elementCount] = null; // Let gc do its work
- return (E)oldValue;
+ return oldValue;
}
/**
@@ -806,7 +832,7 @@ public class Vector
* @param c a collection whose elements will be tested for containment
* in this Vector
* @return true if this Vector contains all of the elements in the
- * specified collection
+ * specified collection
* @throws NullPointerException if the specified collection is null
*/
public synchronized boolean containsAll(Collection c) {
@@ -827,13 +853,13 @@ public class Vector
* @since 1.2
*/
public synchronized boolean addAll(Collection c) {
- modCount++;
+ modCount++;
Object[] a = c.toArray();
int numNew = a.length;
- ensureCapacityHelper(elementCount + numNew);
+ ensureCapacityHelper(elementCount + numNew);
System.arraycopy(a, 0, elementData, elementCount, numNew);
elementCount += numNew;
- return numNew != 0;
+ return numNew != 0;
}
/**
@@ -886,28 +912,28 @@ public class Vector
* specified collection
* @param c elements to be inserted into this Vector
* @return {@code true} if this Vector changed as a result of the call
- * @exception ArrayIndexOutOfBoundsException index out of range (index
- * < 0 || index > size())
+ * @throws ArrayIndexOutOfBoundsException if the index is out of range
+ * ({@code index < 0 || index > size()})
* @throws NullPointerException if the specified collection is null
* @since 1.2
*/
public synchronized boolean addAll(int index, Collection c) {
- modCount++;
- if (index < 0 || index > elementCount)
- throw new ArrayIndexOutOfBoundsException(index);
+ modCount++;
+ if (index < 0 || index > elementCount)
+ throw new ArrayIndexOutOfBoundsException(index);
Object[] a = c.toArray();
- int numNew = a.length;
- ensureCapacityHelper(elementCount + numNew);
+ int numNew = a.length;
+ ensureCapacityHelper(elementCount + numNew);
- int numMoved = elementCount - index;
- if (numMoved > 0)
- System.arraycopy(elementData, index, elementData, index + numNew,
- numMoved);
+ int numMoved = elementCount - index;
+ if (numMoved > 0)
+ System.arraycopy(elementData, index, elementData, index + numNew,
+ numMoved);
System.arraycopy(a, 0, elementData, index, numNew);
- elementCount += numNew;
- return numNew != 0;
+ elementCount += numNew;
+ return numNew != 0;
}
/**
@@ -942,25 +968,61 @@ public class Vector
}
/**
- * Removes from this List all of the elements whose index is between
- * fromIndex, inclusive and toIndex, exclusive. Shifts any succeeding
- * elements to the left (reduces their index).
- * This call shortens the Vector by (toIndex - fromIndex) elements. (If
- * toIndex==fromIndex, this operation has no effect.)
+ * Returns a view of the portion of this List between 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 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.
*
- * @param fromIndex index of first element to be removed
- * @param toIndex index after last element to be removed
+ * 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 operating on 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 the 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 if an endpoint index value is out of range
+ * {@code (fromIndex < 0 || toIndex > size)}
+ * @throws IllegalArgumentException if the endpoint indices are out of order
+ * {@code (fromIndex > toIndex)}
+ */
+ public synchronized List subList(int fromIndex, int toIndex) {
+ return Collections.synchronizedList(super.subList(fromIndex, toIndex),
+ this);
+ }
+
+ /**
+ * Removes from this list all of the elements whose index is between
+ * {@code fromIndex}, inclusive, and {@code toIndex}, exclusive.
+ * Shifts any succeeding elements to the left (reduces their index).
+ * This call shortens the list by {@code (toIndex - fromIndex)} elements.
+ * (If {@code toIndex==fromIndex}, this operation has no effect.)
*/
protected synchronized void removeRange(int fromIndex, int toIndex) {
- modCount++;
- int numMoved = elementCount - toIndex;
+ modCount++;
+ int numMoved = elementCount - toIndex;
System.arraycopy(elementData, toIndex, elementData, fromIndex,
numMoved);
- // Let gc do its work
- int newElementCount = elementCount - (toIndex-fromIndex);
- while (elementCount != newElementCount)
- elementData[--elementCount] = null;
+ // Let gc do its work
+ int newElementCount = elementCount - (toIndex-fromIndex);
+ while (elementCount != newElementCount)
+ elementData[--elementCount] = null;
}
/**
@@ -971,478 +1033,143 @@ public class Vector
private synchronized void writeObject(java.io.ObjectOutputStream s)
throws java.io.IOException
{
- s.defaultWriteObject();
+ s.defaultWriteObject();
}
/**
- * Returns a list-iterator of the elements in this list (in proper
+ * Returns a list iterator over the elements in this list (in proper
* sequence), starting at the specified position in the list.
- * Obeys the general contract of {@link List#listIterator(int)}.
+ * 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.
+ *
+ * The returned list iterator is fail-fast.
*
- *
The list-iterator is fail-fast: if the list is structurally
- * modified at any time after the Iterator is created, in any way except
- * through the list-iterator's own {@code remove} or {@code add}
- * methods, the list-iterator will throw a
- * {@code ConcurrentModificationException}. Thus, in the face of
- * concurrent modification, the iterator fails quickly and cleanly, rather
- * than risking arbitrary, non-deterministic behavior at an undetermined
- * time in the future.
- *
- * @param index index of the first element to be returned from the
- * list-iterator (by a call to {@link ListIterator#next})
- * @return a list-iterator of the elements in this list (in proper
- * sequence), starting at the specified position in the list
* @throws IndexOutOfBoundsException {@inheritDoc}
*/
public synchronized ListIterator listIterator(int index) {
- if (index < 0 || index > elementCount)
+ if (index < 0 || index > elementCount)
throw new IndexOutOfBoundsException("Index: "+index);
- return new VectorIterator(index, elementCount);
+ return new ListItr(index);
}
/**
- * {@inheritDoc}
+ * Returns a list iterator over the elements in this list (in proper
+ * sequence).
+ *
+ * The returned list iterator is fail-fast.
+ *
+ * @see #listIterator(int)
*/
public synchronized ListIterator listIterator() {
- return new VectorIterator(0, elementCount);
+ return new ListItr(0);
}
/**
* Returns an iterator over the elements in this list in proper sequence.
*
+ * The returned iterator is fail-fast.
+ *
* @return an iterator over the elements in this list in proper sequence
*/
public synchronized Iterator iterator() {
- return new VectorIterator(0, elementCount);
+ return new Itr();
}
/**
- * Helper method to access array elements under synchronization by
- * iterators. The caller performs index check with respect to
- * expected bounds, so errors accessing the element are reported
- * as ConcurrentModificationExceptions.
+ * An optimized version of AbstractList.Itr
*/
- final synchronized Object iteratorGet(int index, int expectedModCount) {
- if (modCount == expectedModCount) {
- try {
- return elementData[index];
- } catch(IndexOutOfBoundsException fallThrough) {
- }
- }
- throw new ConcurrentModificationException();
- }
+ private class Itr implements Iterator {
+ int cursor; // index of next element to return
+ int lastRet = -1; // index of last element returned; -1 if no such
+ int expectedModCount = modCount;
- /**
- * Streamlined specialization of AbstractList version of iterator.
- * Locally perfroms bounds checks, but relies on outer Vector
- * to access elements under synchronization.
- */
- private final class VectorIterator implements ListIterator {
- int cursor; // Index of next element to return;
- int fence; // Upper bound on cursor (cache of size())
- int lastRet; // Index of last element, or -1 if no such
- int expectedModCount; // To check for CME
-
- VectorIterator(int index, int fence) {
- this.cursor = index;
- this.fence = fence;
- this.lastRet = -1;
- this.expectedModCount = Vector.this.modCount;
- }
-
- public boolean hasNext() {
- return cursor < fence;
- }
-
- public boolean hasPrevious() {
- return cursor > 0;
- }
-
- public int nextIndex() {
- return cursor;
- }
-
- public int previousIndex() {
- return cursor - 1;
- }
-
- public E next() {
- int i = cursor;
- if (i >= fence)
- throw new NoSuchElementException();
- Object next = Vector.this.iteratorGet(i, expectedModCount);
- lastRet = i;
- cursor = i + 1;
- return (E)next;
- }
-
- public E previous() {
- int i = cursor - 1;
- if (i < 0)
- throw new NoSuchElementException();
- Object prev = Vector.this.iteratorGet(i, expectedModCount);
- lastRet = i;
- cursor = i;
- return (E)prev;
+ public boolean hasNext() {
+ // Racy but within spec, since modifications are checked
+ // within or after synchronization in next/previous
+ return cursor != elementCount;
}
- public void set(E e) {
- if (lastRet < 0)
- throw new IllegalStateException();
- if (Vector.this.modCount != expectedModCount)
- throw new ConcurrentModificationException();
- try {
- Vector.this.set(lastRet, e);
- expectedModCount = Vector.this.modCount;
- } catch (IndexOutOfBoundsException ex) {
- throw new ConcurrentModificationException();
- }
- }
-
- public void remove() {
- int i = lastRet;
- if (i < 0)
- throw new IllegalStateException();
- if (Vector.this.modCount != expectedModCount)
- throw new ConcurrentModificationException();
- try {
- Vector.this.remove(i);
- if (i < cursor)
- cursor--;
- lastRet = -1;
- fence = Vector.this.size();
- expectedModCount = Vector.this.modCount;
- } catch (IndexOutOfBoundsException ex) {
- throw new ConcurrentModificationException();
- }
- }
-
- public void add(E e) {
- if (Vector.this.modCount != expectedModCount)
- throw new ConcurrentModificationException();
- try {
+ public E next() {
+ synchronized (Vector.this) {
+ checkForComodification();
int i = cursor;
- Vector.this.add(i, e);
+ if (i >= elementCount)
+ throw new NoSuchElementException();
cursor = i + 1;
- lastRet = -1;
- fence = Vector.this.size();
- expectedModCount = Vector.this.modCount;
- } catch (IndexOutOfBoundsException ex) {
- throw new ConcurrentModificationException();
- }
- }
- }
-
- /**
- * Returns a view of the portion of this List between 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 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 operating on 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 the 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 endpoint index value out of range
- * (fromIndex < 0 || toIndex > size)
- * @throws IllegalArgumentException endpoint indices out of order
- * (fromIndex > toIndex)
- */
- public synchronized List subList(int fromIndex, int toIndex) {
- return new VectorSubList(this, this, fromIndex, fromIndex, toIndex);
- }
-
- /**
- * This class specializes the AbstractList version of SubList to
- * avoid the double-indirection penalty that would arise using a
- * synchronized wrapper, as well as to avoid some unnecessary
- * checks in sublist iterators.
- */
- private static final class VectorSubList extends AbstractList implements RandomAccess {
- final Vector base; // base list
- final AbstractList parent; // Creating list
- final int baseOffset; // index wrt Vector
- final int parentOffset; // index wrt parent
- int length; // length of sublist
-
- VectorSubList(Vector base, AbstractList parent, int baseOffset,
- int fromIndex, int toIndex) {
- if (fromIndex < 0)
- throw new IndexOutOfBoundsException("fromIndex = " + fromIndex);
- if (toIndex > parent.size())
- throw new IndexOutOfBoundsException("toIndex = " + toIndex);
- if (fromIndex > toIndex)
- throw new IllegalArgumentException("fromIndex(" + fromIndex +
- ") > toIndex(" + toIndex + ")");
-
- this.base = base;
- this.parent = parent;
- this.baseOffset = baseOffset;
- this.parentOffset = fromIndex;
- this.length = toIndex - fromIndex;
- modCount = base.modCount;
- }
-
- /**
- * Returns an IndexOutOfBoundsException with nicer message
- */
- private IndexOutOfBoundsException indexError(int index) {
- return new IndexOutOfBoundsException("Index: " + index +
- ", Size: " + length);
- }
-
- public E set(int index, E element) {
- synchronized(base) {
- if (index < 0 || index >= length)
- throw indexError(index);
- if (base.modCount != modCount)
- throw new ConcurrentModificationException();
- return base.set(index + baseOffset, element);
- }
- }
-
- public E get(int index) {
- synchronized(base) {
- if (index < 0 || index >= length)
- throw indexError(index);
- if (base.modCount != modCount)
- throw new ConcurrentModificationException();
- return base.get(index + baseOffset);
- }
- }
-
- public int size() {
- synchronized(base) {
- if (base.modCount != modCount)
- throw new ConcurrentModificationException();
- return length;
- }
- }
-
- public void add(int index, E element) {
- synchronized(base) {
- if (index < 0 || index > length)
- throw indexError(index);
- if (base.modCount != modCount)
- throw new ConcurrentModificationException();
- parent.add(index + parentOffset, element);
- length++;
- modCount = base.modCount;
+ return elementData(lastRet = i);
}
}
- public E remove(int index) {
- synchronized(base) {
- if (index < 0 || index >= length)
- throw indexError(index);
- if (base.modCount != modCount)
- throw new ConcurrentModificationException();
- E result = parent.remove(index + parentOffset);
- length--;
- modCount = base.modCount;
- return result;
+ public void remove() {
+ if (lastRet == -1)
+ throw new IllegalStateException();
+ synchronized (Vector.this) {
+ checkForComodification();
+ Vector.this.remove(lastRet);
+ expectedModCount = modCount;
}
+ cursor = lastRet;
+ lastRet = -1;
}
- protected void removeRange(int fromIndex, int toIndex) {
- synchronized(base) {
- if (base.modCount != modCount)
- throw new ConcurrentModificationException();
- parent.removeRange(fromIndex + parentOffset,
- toIndex + parentOffset);
- length -= (toIndex-fromIndex);
- modCount = base.modCount;
- }
- }
-
- public boolean addAll(Collection c) {
- return addAll(length, c);
- }
-
- public boolean addAll(int index, Collection c) {
- synchronized(base) {
- if (index < 0 || index > length)
- throw indexError(index);
- int cSize = c.size();
- if (cSize==0)
- return false;
-
- if (base.modCount != modCount)
- throw new ConcurrentModificationException();
- parent.addAll(parentOffset + index, c);
- modCount = base.modCount;
- length += cSize;
- return true;
- }
- }
-
- public boolean equals(Object o) {
- synchronized(base) {return super.equals(o);}
- }
-
- public int hashCode() {
- synchronized(base) {return super.hashCode();}
- }
-
- public int indexOf(Object o) {
- synchronized(base) {return super.indexOf(o);}
- }
-
- public int lastIndexOf(Object o) {
- synchronized(base) {return super.lastIndexOf(o);}
+ final void checkForComodification() {
+ if (modCount != expectedModCount)
+ throw new ConcurrentModificationException();
}
+ }
- public List subList(int fromIndex, int toIndex) {
- return new VectorSubList(base, this, fromIndex + baseOffset,
- fromIndex, toIndex);
+ /**
+ * An optimized version of AbstractList.ListItr
+ */
+ final class ListItr extends Itr implements ListIterator {
+ ListItr(int index) {
+ super();
+ cursor = index;
}
- public Iterator iterator() {
- synchronized(base) {
- return new VectorSubListIterator(this, 0);
- }
+ public boolean hasPrevious() {
+ return cursor != 0;
}
- public synchronized ListIterator listIterator() {
- synchronized(base) {
- return new VectorSubListIterator(this, 0);
- }
+ public int nextIndex() {
+ return cursor;
}
- public ListIterator listIterator(int index) {
- synchronized(base) {
- if (index < 0 || index > length)
- throw indexError(index);
- return new VectorSubListIterator(this, index);
- }
+ public int previousIndex() {
+ return cursor - 1;
}
- /**
- * Same idea as VectorIterator, except routing structural
- * change operations through the sublist.
- */
- private static final class VectorSubListIterator implements ListIterator {
- final Vector base; // base list
- final VectorSubList outer; // Sublist creating this iteraor
- final int offset; // cursor offset wrt base
- int cursor; // Current index
- int fence; // Upper bound on cursor
- int lastRet; // Index of returned element, or -1
- int expectedModCount; // Expected modCount of base Vector
-
- VectorSubListIterator(VectorSubList list, int index) {
- this.lastRet = -1;
- this.cursor = index;
- this.outer = list;
- this.offset = list.baseOffset;
- this.fence = list.length;
- this.base = list.base;
- this.expectedModCount = base.modCount;
- }
-
- public boolean hasNext() {
- return cursor < fence;
- }
-
- public boolean hasPrevious() {
- return cursor > 0;
- }
-
- public int nextIndex() {
- return cursor;
- }
-
- public int previousIndex() {
- return cursor - 1;
- }
-
- public E next() {
- int i = cursor;
- if (cursor >= fence)
- throw new NoSuchElementException();
- Object next = base.iteratorGet(i + offset, expectedModCount);
- lastRet = i;
- cursor = i + 1;
- return (E)next;
- }
-
- public E previous() {
+ public E previous() {
+ synchronized (Vector.this) {
+ checkForComodification();
int i = cursor - 1;
if (i < 0)
throw new NoSuchElementException();
- Object prev = base.iteratorGet(i + offset, expectedModCount);
- lastRet = i;
cursor = i;
- return (E)prev;
- }
-
- public void set(E e) {
- if (lastRet < 0)
- throw new IllegalStateException();
- if (base.modCount != expectedModCount)
- throw new ConcurrentModificationException();
- try {
- outer.set(lastRet, e);
- expectedModCount = base.modCount;
- } catch (IndexOutOfBoundsException ex) {
- throw new ConcurrentModificationException();
- }
+ return elementData(lastRet = i);
}
+ }
- public void remove() {
- int i = lastRet;
- if (i < 0)
- throw new IllegalStateException();
- if (base.modCount != expectedModCount)
- throw new ConcurrentModificationException();
- try {
- outer.remove(i);
- if (i < cursor)
- cursor--;
- lastRet = -1;
- fence = outer.length;
- expectedModCount = base.modCount;
- } catch (IndexOutOfBoundsException ex) {
- throw new ConcurrentModificationException();
- }
+ public void set(E e) {
+ if (lastRet == -1)
+ throw new IllegalStateException();
+ synchronized (Vector.this) {
+ checkForComodification();
+ Vector.this.set(lastRet, e);
}
+ }
- public void add(E e) {
- if (base.modCount != expectedModCount)
- throw new ConcurrentModificationException();
- try {
- int i = cursor;
- outer.add(i, e);
- cursor = i + 1;
- lastRet = -1;
- fence = outer.length;
- expectedModCount = base.modCount;
- } catch (IndexOutOfBoundsException ex) {
- throw new ConcurrentModificationException();
- }
+ public void add(E e) {
+ int i = cursor;
+ synchronized (Vector.this) {
+ checkForComodification();
+ Vector.this.add(i, e);
+ expectedModCount = modCount;
}
+ cursor = i + 1;
+ lastRet = -1;
}
}
}
-
-
-