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/* VectorD.java
Copyright 2003, Bil Lewis
This program is free software; you can redistribute it and/or modify
it under the terms of the GNU General Public License as published by
the Free Software Foundation; either version 2 of the License, or
(at your option) any later version.
This program 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 for more details.
You should have received a copy of the GNU General Public License
along with this program; if not, write to the Free Software
Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
*/
/*
Use a duplicate of Sun's Vector class so that the ODB can load
an instrumented version of Vector &c without blowing up.
And it's not synchronized. And it's final. (Faster)
But some of the Java classes appear to use Vectors. :-(
* @(#)VectorD.java 1.71 00/04/18
*
* Copyright 1994-2000 Sun Microsystems, Inc. All Rights Reserved.
*
* This software is the proprietary information of Sun Microsystems, Inc.
* Use is subject to license terms.
*
*/
//package java.util;
package com.lambda.Debugger;
import java.util.*;
/**
* The VectorD
class implements a growable array of
* objects. Like an array, it contains components that can be
* accessed using an integer index. However, the size of a
* VectorD
can grow or shrink as needed to accommodate
* adding and removing items after the VectorD
has been created.
*
* Each vector tries to optimize storage management by maintaining a
* capacity
and a capacityIncrement
. The
* capacity
is always at least as large as the vector
* size; it is usually larger because as components are added to the
* vector, the vector's storage increases in chunks the size of
* capacityIncrement
. An application can increase the
* capacity of a vector before inserting a large number of
* components; this reduces the amount of incremental reallocation.
*
* As of the Java 2 platform v1.2, this class has been retrofitted to
* implement List, so that it becomes a part of Java's collection framework.
* Unlike the new collection implementations, VectorD is .
*
* The Iterators returned by VectorD's iterator and listIterator
* methods are fail-fast: if the VectorD 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 VectorD's elements method are not
* fail-fast.
*
* @author Lee Boynton
* @author Jonathan Payne
* @version 1.71, 04/18/00
* @see Collection
* @see List
* @see ArrayList
* @see LinkedList
* @since JDK1.0
*/
//public class VectorD extends MyAbstractList implements List, Cloneable, java.io.Serializable {
public final class VectorD extends Vector {
/**
* The array buffer into which the components of the vector are
* stored. The capacity of the vector is the length of this array buffer,
* and is at least large enough to contain all the vector's elements.
*
* Any array elements following the last element in the VectorD are null.
*
* @serial
*/
protected Object elementData[];
/**
* The number of valid components in this VectorD object.
* Components elementData[0] through
* elementData[elementCount-1] are the actual items.
*
* @serial
*/
protected int elementCount;
/**
* The amount by which the capacity of the vector is automatically
* incremented when its size becomes greater than its capacity. If
* the capacity increment is less than or equal to zero, the capacity
* of the vector is doubled each time it needs to grow.
*
* @serial
*/
protected int capacityIncrement;
/** use serialVersionUID from JDK 1.0.2 for interoperability */
private static final long serialVersionUID = -2767605614048989439L;
/**
* Constructs an empty vector with the specified initial capacity and
* capacity increment.
*
* @param initialCapacity the initial capacity of the vector.
* @param capacityIncrement the amount by which the capacity is
* increased when the vector overflows.
* @exception IllegalArgumentException if the specified initial capacity
* is negative
*/
public VectorD(int initialCapacity, int capacityIncrement) {
super();
if (initialCapacity < 0)
throw new IllegalArgumentException("Illegal Capacity: "+
initialCapacity);
this.elementData = new Object[initialCapacity];
this.capacityIncrement = capacityIncrement;
}
/**
* Constructs an empty vector with the specified initial capacity and
* with its capacity increment equal to zero.
*
* @param initialCapacity the initial capacity of the vector.
* @exception IllegalArgumentException if the specified initial capacity
* is negative
*/
public VectorD(int initialCapacity) {
this(initialCapacity, 0);
}
/**
* Constructs an empty vector so that its internal data array
* has size 10 and its standard capacity increment is
* zero.
*/
public VectorD() {
this(10);
}
/**
* Constructs a vector containing the elements of the specified
* collection, in the order they are returned by the collection's
* iterator.
*
* @param c the collection whose elements are to be placed into this
* vector.
* @since 1.2
*/
public VectorD(Collection c) {
elementCount = c.size();
elementData = new Object[(elementCount*110)/100]; // 10% for growth
c.toArray(elementData);
}
/**
* Copies the components of this vector into the specified array. The
* item at index k in this vector is copied into component
* k of anArray. The array must be big enough to hold
* all the objects in this vector, else an
* IndexOutOfBoundsException is thrown.
*
* @param anArray the array into which the components get copied.
*/
public void copyInto(Object anArray[]) {
System.arraycopy(elementData, 0, anArray, 0, elementCount);
}
/**
* Trims the capacity of this vector to be the vector's current
* size. If the capacity of this cector is larger than its current
* size, then the capacity is changed to equal the size by replacing
* its internal data array, kept in the field elementData,
* with a smaller one. An application can use this operation to
* minimize the storage of a vector.
*/
public void trimToSize() {
modCount++;
int oldCapacity = elementData.length;
if (elementCount < oldCapacity) {
Object oldData[] = elementData;
elementData = new Object[elementCount];
System.arraycopy(oldData, 0, elementData, 0, elementCount);
}
}
/**
* Increases the capacity of this vector, if necessary, to ensure
* that it can hold at least the number of components specified by
* the minimum capacity argument.
*
*
If the current capacity of this vector is less than
* minCapacity, then its capacity is increased by replacing its
* internal data array, kept in the field elementData, with a
* larger one. The size of the new data array will be the old size plus
* capacityIncrement, unless the value of
* capacityIncrement is less than or equal to zero, in which case
* the new capacity will be twice the old capacity; but if this new size
* is still smaller than minCapacity, then the new capacity will
* be minCapacity.
*
* @param minCapacity the desired minimum capacity.
*/
public void ensureCapacity(int minCapacity) {
modCount++;
ensureCapacityHelper(minCapacity);
}
/**
* This implements the un semantics of ensureCapacity.
* methods in this class can internally call this
* method for ensuring capacity without incurring the cost of an
* extra synchronization.
*
* @see java.util.VectorD#ensureCapacity(int)
*/
private void ensureCapacityHelper(int minCapacity) {
int oldCapacity = elementData.length;
if (minCapacity > oldCapacity) {
Object oldData[] = elementData;
int newCapacity = (capacityIncrement > 0) ?
(oldCapacity + capacityIncrement) : (oldCapacity * 4);
if (newCapacity < minCapacity) {
newCapacity = minCapacity;
}
elementData = new Object[newCapacity];
System.arraycopy(oldData, 0, elementData, 0, elementCount);
}
}
/**
* Sets the size of this vector. If the new size is greater than the
* current size, new null
items are added to the end of
* the vector. If the new size is less than the current size, all
* components at index newSize
and greater are discarded.
*
* @param newSize the new size of this vector.
* @throws ArrayIndexOutOfBoundsException if new size is negative.
*/
public void setSize(int newSize) {
modCount++;
if (newSize > elementCount) {
ensureCapacityHelper(newSize);
} else {
for (int i = newSize ; i < elementCount ; i++) {
elementData[i] = null;
}
}
elementCount = newSize;
}
/**
* Returns the current capacity of this vector.
*
* @return the current capacity (the length of its internal
* data arary, kept in the field elementData
* of this vector.
*/
public int capacity() {
return elementData.length;
}
/**
* Returns the number of components in this vector.
*
* @return the number of components in this vector.
*/
public int size() {
return elementCount;
}
/**
* Tests if this vector has no components.
*
* @return true
if and only if this vector has
* no components, that is, its size is zero;
* false
otherwise.
*/
public boolean isEmpty() {
return elementCount == 0;
}
/**
* Returns an enumeration of the components of this vector. The
* returned Enumeration object will generate all items in
* this vector. The first item generated is the item at index 0,
* then the item at index 1, and so on.
*
* @return an enumeration of the components of this vector.
* @see Enumeration
* @see Iterator
*/
public Enumeration elements() {
return new Enumeration() {
int count = 0;
public boolean hasMoreElements() {
return count < elementCount;
}
public Object nextElement() {
if (count < elementCount) {
return elementData[count++];
}
throw new NoSuchElementException("VectorD Enumeration");
}
};
}
/**
* Tests if the specified object is a component in this vector.
*
* @param elem an object.
* @return true
if and only if the specified object
* is the same as a component in this vector, as determined by the
* equals method; false
otherwise.
*/
public boolean contains(Object elem) {
return indexOf(elem, 0) >= 0;
}
/**
* Searches for the first occurence of the given argument, testing
* for equality using the equals
method.
*
* @param elem an object.
* @return the index of the first occurrence of the argument in this
* vector, that is, the smallest value k such that
* elem.equals(elementData[k]) is true;
* returns -1
if the object is not found.
* @see Object#equals(Object)
*/
public int indexOf(Object elem) {
return indexOf(elem, 0);
}
/**
* Searches for the first occurence of the given argument, beginning
* the search at index
, and testing for equality using
* the equals
method.
*
* @param elem an object.
* @param index the non-negative index to start searching from.
* @return the index of the first occurrence of the object argument in
* this vector at position index
or later in the
* vector, that is, the smallest value k such that
* elem.equals(elementData[k]) and (k >= index) is
* true; returns -1
if the object is not
* found. (Returns -1
if index >= the
* current size of this VectorD.)
* @exception IndexOutOfBoundsException if index is negative.
* @see Object#equals(Object)
*/
public int indexOf(Object elem, int index) {
if (elem == null) {
for (int i = index ; i < elementCount ; i++)
if (elementData[i]==null)
return i;
} else {
for (int i = index ; i < elementCount ; i++)
if (elem == elementData[i])
return i;
}
return -1;
}
/**
* Returns the index of the last occurrence of the specified object in
* this vector.
*
* @param elem the desired component.
* @return the index of the last occurrence of the specified object in
* this vector, that is, the largest value k such that
* elem.equals(elementData[k]) is true;
* returns -1
if the object is not found.
*/
public int lastIndexOf(Object elem) {
return lastIndexOf(elem, elementCount-1);
}
/**
* Searches backwards for the specified object, starting from the
* specified index, and returns an index to it.
*
* @param elem the desired component.
* @param index the index to start searching from.
* @return the index of the last occurrence of the specified object in this
* vector at position less than or equal to index
in
* the vector, that is, the largest value k such that
* elem.equals(elementData[k]) and (k <= index) is
* true; -1
if the object is not found.
* (Returns -1
if index is negative.)
* @exception IndexOutOfBoundsException if index is greater
* than or equal to the current size of this vector.
*/
public int lastIndexOf(Object elem, int index) {
if (index >= elementCount)
throw new IndexOutOfBoundsException(index + " >= "+ elementCount);
if (elem == null) {
for (int i = index; i >= 0; i--)
if (elementData[i]==null)
return i;
} else {
for (int i = index; i >= 0; i--)
if (elem == elementData[i])
return i;
}
return -1;
}
/**
* Returns the component at the specified index.
*
* This method is identical in functionality to the get method
* (which is part of the List interface).
*
* @param index an index into this vector.
* @return the component at the specified index.
* @exception ArrayIndexOutOfBoundsException if the index
* is negative or not less than the current size of this
* VectorD object.
* given.
* @see #get(int)
* @see List
*/
public Object elementAt(int index) {
if (index >= elementCount) {
throw new ArrayIndexOutOfBoundsException(index + " >= " + elementCount);
}
/* Since try/catch is free, except when the exception is thrown,
put in this extra try/catch to catch negative indexes and
display a more informative error message. This might not
be appropriate, especially if we have a decent debugging
environment - JP. */
try {
return elementData[index];
} catch (ArrayIndexOutOfBoundsException e) {
throw new ArrayIndexOutOfBoundsException(index + " < 0");
}
}
/**
* Returns the first component (the item at index 0) of
* this vector.
*
* @return the first component of this vector.
* @exception NoSuchElementException if this vector has no components.
*/
public Object firstElement() {
if (elementCount == 0) {
throw new NoSuchElementException();
}
return elementData[0];
}
/**
* Returns the last component of the vector.
*
* @return the last component of the vector, i.e., the component at index
* size() - 1
.
* @exception NoSuchElementException if this vector is empty.
*/
public Object lastElement() {
if (elementCount == 0) {
throw new NoSuchElementException();
}
return elementData[elementCount - 1];
}
/**
* Sets the component at the specified index
of this
* vector to be the specified object. The previous component at that
* position is discarded.
*
* The index must be a value greater than or equal to 0
* and less than the current size of the vector.
*
* This method is identical in functionality to the set method
* (which is part of the List interface). Note that the set method reverses
* the order of the parameters, to more closely match array usage. Note
* also that the set method returns the old value that was stored at the
* specified position.
*
* @param obj what the component is to be set to.
* @param index the specified index.
* @exception ArrayIndexOutOfBoundsException if the index was invalid.
* @see #size()
* @see List
* @see #set(int, java.lang.Object)
*/
public void setElementAt(Object obj, int index) {
if (index >= elementCount) {
throw new ArrayIndexOutOfBoundsException(index + " >= " +
elementCount);
}
elementData[index] = obj;
}
/**
* Deletes the component at the specified index. Each component in
* this vector with an index greater or equal to the specified
* index
is shifted downward to have an index one
* smaller than the value it had previously. The size of this vector
* is decreased by 1.
*
* The index must be a value greater than or equal to 0
* and less than the current size of the vector.
*
* This method is identical in functionality to the remove method
* (which is part of the List interface). Note that the remove method
* returns the old value that was stored at the specified position.
*
* @param index the index of the object to remove.
* @exception ArrayIndexOutOfBoundsException if the index was invalid.
* @see #size()
* @see #remove(int)
* @see List
*/
public 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 */
}
/**
* Inserts the specified object as a component in this vector at the
* specified index
. Each component in this vector with
* an index greater or equal to the specified index
is
* shifted upward to have an index one greater than the value it had
* previously.
*
* The index must be a value greater than or equal to 0
* and less than or equal to the current size of the vector. (If the
* index is equal to the current size of the vector, the new element
* is appended to the VectorD.)
*
* This method is identical in functionality to the add(Object, int) method
* (which is part of the List interface). Note that the add method reverses
* the order of the parameters, to more closely match array usage.
*
* @param obj the component to insert.
* @param index where to insert the new component.
* @exception ArrayIndexOutOfBoundsException if the index was invalid.
* @see #size()
* @see #add(int, Object)
* @see List
*/
public void insertElementAt(Object obj, int index) {
modCount++;
if (index >= elementCount + 1) {
throw new ArrayIndexOutOfBoundsException(index
+ " > " + elementCount);
}
ensureCapacityHelper(elementCount + 1);
System.arraycopy(elementData, index, elementData, index + 1, elementCount - index);
elementData[index] = obj;
elementCount++;
}
/**
* Adds the specified component to the end of this vector,
* increasing its size by one. The capacity of this vector is
* increased if its size becomes greater than its capacity.
*
* This method is identical in functionality to the add(Object) method
* (which is part of the List interface).
*
* @param obj the component to be added.
* @see #add(Object)
* @see List
*/
public void addElement(Object obj) {
modCount++;
ensureCapacityHelper(elementCount + 1);
elementData[elementCount++] = obj;
}
/**
* Removes the first (lowest-indexed) occurrence of the argument
* from this vector. If the object is found in this vector, each
* component in the vector with an index greater or equal to the
* 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).
*
* @param obj the component to be removed.
* @return true
if the argument was a component of this
* vector; false
otherwise.
* @see List#remove(Object)
* @see List
*/
public boolean removeElement(Object obj) {
modCount++;
int i = indexOf(obj);
if (i >= 0) {
removeElementAt(i);
return true;
}
return false;
}
/**
* Removes all components from this vector and sets its size to zero.
*
* This method is identical in functionality to the clear method
* (which is part of the List interface).
*
* @see #clear
* @see List
*/
public void removeAllElements() {
// Let gc do its work
for (int i = 0; i < elementCount; i++)
elementData[i] = null;
elementCount = 0;
}
/**
* Returns a clone of this vector. The copy will contain a
* reference to a clone of the internal data array, not a reference
* to the original internal data array of this VectorD object.
*
* @return a clone of this vector.
public Object clone() {
try {
VectorD v = (VectorD)super.clone();
v.elementData = new Object[elementCount];
System.arraycopy(elementData, 0, v.elementData, 0, elementCount);
v.modCount = 0;
return v;
} catch (CloneNotSupportedException e) {
// this shouldn't happen, since we are Cloneable
throw new InternalError();
}
}
*/
/**
* Returns an array containing all of the elements in this VectorD
* in the correct order.
*
* @since 1.2
*/
public Object[] toArray() {
Object[] result = new Object[elementCount];
System.arraycopy(elementData, 0, result, 0, elementCount);
return result;
}
/**
* Returns an array containing all of the elements in this VectorD in the
* correct order. The runtime type of the returned array is that of the
* specified array. If the VectorD fits in the specified array, it is
* returned therein. Otherwise, a new array is allocated with the runtime
* type of the specified array and the size of this VectorD.
*
* If the VectorD fits in the specified array with room to spare
* (i.e., the array has more elements than the VectorD),
* the element in the array immediately following the end of the
* VectorD is set to null. This is useful in determining the length
* of the VectorD only if the caller knows that the VectorD
* does not contain any null elements.
*
* @param a the array into which the elements of the VectorD are to
* be stored, if it is big enough; otherwise, a new array of the
* same runtime type is allocated for this purpose.
* @return an array containing the elements of the VectorD.
* @exception ArrayStoreException the runtime type of a is not a supertype
* of the runtime type of every element in this VectorD.
*/
public Object[] toArray(Object a[]) {
if (a.length < elementCount)
a = (Object[])java.lang.reflect.Array.newInstance(
a.getClass().getComponentType(), elementCount);
System.arraycopy(elementData, 0, a, 0, elementCount);
if (a.length > elementCount)
a[elementCount] = null;
return a;
}
// Positional Access Operations
/**
* Returns the element at the specified position in this VectorD.
*
* @param index index of element to return.
* @exception ArrayIndexOutOfBoundsException index is out of range (index
* < 0 || index >= size()).
* @since 1.2
*/
public Object get(int index) {
if (index >= elementCount)
throw new ArrayIndexOutOfBoundsException(index);
return elementData[index];
}
/**
* Replaces the element at the specified position in this VectorD with the
* specified element.
*
* @param index index of element to replace.
* @param element element to be stored at the specified position.
* @return the element previously at the specified position.
* @exception ArrayIndexOutOfBoundsException index out of range
* (index < 0 || index >= size()).
* @exception IllegalArgumentException fromIndex > toIndex.
* @since 1.2
*/
public Object set(int index, Object element) {
if (index >= elementCount)
throw new ArrayIndexOutOfBoundsException(index);
Object oldValue = elementData[index];
elementData[index] = element;
return oldValue;
}
/**
* Appends the specified element to the end of this VectorD.
*
* @param o element to be appended to this VectorD.
* @return true (as per the general contract of Collection.add).
* @since 1.2
*/
public boolean add(Object o) {
modCount++;
ensureCapacityHelper(elementCount + 1);
elementData[elementCount++] = o;
return true;
}
/**
* Removes the first occurrence of the specified element in this VectorD
* If the VectorD does not contain the element, it is unchanged. More
* formally, removes the element with the lowest index i such that
* (o==null ? get(i)==null : o.equals(get(i)))
(if such
* an element exists).
*
* @param o element to be removed from this VectorD, if present.
* @return true if the VectorD contained the specified element.
* @since 1.2
*/
public boolean remove(Object o) {
return removeElement(o);
}
/**
* Inserts the specified element at the specified position in this VectorD.
* Shifts the element currently at that position (if any) and any
* subsequent elements to the right (adds one to their indices).
*
* @param index index at which the specified element is to be inserted.
* @param element element to be inserted.
* @exception ArrayIndexOutOfBoundsException index is out of range
* (index < 0 || index > size()).
* @since 1.2
*/
public void add(int index, Object element) {
insertElementAt(element, index);
}
/**
* Removes the element at the specified position in this VectorD.
* shifts any subsequent elements to the left (subtracts one from their
* indices). Returns the element that was removed from the VectorD.
*
* @exception ArrayIndexOutOfBoundsException index out of range (index
* < 0 || index >= size()).
* @since 1.2
*/
public Object 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
return oldValue;
}
/**
* Removes all of the elements from this VectorD. The VectorD will
* be empty after this call returns (unless it throws an exception).
*
* @since 1.2
*/
public void clear() {
removeAllElements();
}
// Bulk Operations
/**
* Returns true if this VectorD contains all of the elements in the
* specified Collection.
*
* @return true if this VectorD contains all of the elements in the
* specified collection.
*/
public boolean containsAll(Collection c) {
return super.containsAll(c);
}
/**
* Appends all of the elements in the specified Collection to the end of
* this VectorD, in the order that they are returned by the specified
* Collection's Iterator. The behavior of this operation is undefined if
* the specified Collection is modified while the operation is in progress.
* (This implies that the behavior of this call is undefined if the
* specified Collection is this VectorD, and this VectorD is nonempty.)
*
* @param c elements to be inserted into this VectorD.
* @exception ArrayIndexOutOfBoundsException index out of range (index
* < 0 || index > size()).
* @since 1.2
*/
public boolean addAll(Collection c) {
modCount++;
int numNew = c.size();
ensureCapacityHelper(elementCount + numNew);
Iterator e = c.iterator();
for (int i=0; i elementCount)
throw new ArrayIndexOutOfBoundsException(index);
int numNew = c.size();
ensureCapacityHelper(elementCount + numNew);
int numMoved = elementCount - index;
if (numMoved > 0)
System.arraycopy(elementData, index, elementData, index + numNew,
numMoved);
Iterator e = c.iterator();
for (int i=0; iequal. (Two elements e1
and
* e2
are equal if (e1==null ? e2==null :
* e1.equals(e2))
.) In other words, two Lists are defined to be
* equal if they contain the same elements in the same order.
*
* @param o the Object to be compared for equality with this VectorD.
* @return true if the specified Object is equal to this VectorD
*/
public boolean equals(Object o) {
return super.equals(o);
}
/**
* Returns the hash code value for this VectorD.
*/
public int hashCode() {
return super.hashCode();
}
/**
* Returns a string representation of this VectorD, containing
* the String representation of each element.
*/
protected int idCounter = 0;
protected int id=idCounter++;
public String toString() {
return "";
}
/**
* 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 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
* fromIndex, inclusive and toIndex, exclusive. Shifts any succeeding
* elements to the left (reduces their index).
* This call shortens the ArrayList by (toIndex - fromIndex) elements. (If
* toIndex==fromIndex, this operation has no effect.)
*
* @param fromIndex index of first element to be removed.
* @param toIndex index after last element to be removed.
*/
protected void removeRange(int fromIndex, int 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;
}
}