/*
* 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., 675 Mass Ave, Cambridge, MA 02139, USA.
*/
/*
* FastVector.java
* Copyright (C) 1999 Eibe Frank
*
*/
package weka.core;
import java.io.Serializable;
import java.util.Enumeration;
/**
* Implements a fast vector class without synchronized
* methods. Replaces java.util.Vector. (Synchronized methods tend to
* be slow.)
*
* @author Eibe Frank (eibe@cs.waikato.ac.nz)
* @version $Revision: 1.13 $
*/
public class FastVector
implements Copyable, Serializable {
/** for serialization */
private static final long serialVersionUID = -2173635135622930169L;
/**
* Class for enumerating the vector's elements.
*/
public class FastVectorEnumeration implements Enumeration {
/** The counter. */
private int m_Counter;
// These JML commands say how m_Counter implements Enumeration
//@ in moreElements;
//@ private represents moreElements = m_Counter < m_Vector.size();
//@ private invariant 0 <= m_Counter && m_Counter <= m_Vector.size();
/** The vector. */
private /*@non_null@*/ FastVector m_Vector;
/** Special element. Skipped during enumeration. */
private int m_SpecialElement;
//@ private invariant -1 <= m_SpecialElement;
//@ private invariant m_SpecialElement < m_Vector.size();
//@ private invariant m_SpecialElement>=0 ==> m_Counter!=m_SpecialElement;
/**
* Constructs an enumeration.
*
* @param vector the vector which is to be enumerated
*/
public FastVectorEnumeration(/*@non_null@*/FastVector vector) {
m_Counter = 0;
m_Vector = vector;
m_SpecialElement = -1;
}
/**
* Constructs an enumeration with a special element.
* The special element is skipped during the enumeration.
*
* @param vector the vector which is to be enumerated
* @param special the index of the special element
*/
//@ requires 0 <= special && special < vector.size();
public FastVectorEnumeration(/*@non_null@*/FastVector vector, int special){
m_Vector = vector;
m_SpecialElement = special;
if (special == 0) {
m_Counter = 1;
} else {
m_Counter = 0;
}
}
/**
* Tests if there are any more elements to enumerate.
*
* @return true if there are some elements left
*/
public final /*@pure@*/ boolean hasMoreElements() {
if (m_Counter < m_Vector.size()) {
return true;
}
return false;
}
/**
* Returns the next element.
*
* @return the next element to be enumerated
*/
//@ also requires hasMoreElements();
public final Object nextElement() {
Object result = m_Vector.elementAt(m_Counter);
m_Counter++;
if (m_Counter == m_SpecialElement) {
m_Counter++;
}
return result;
}
}
/** The array of objects. */
private /*@spec_public@*/ Object[] m_Objects;
//@ invariant m_Objects != null;
//@ invariant m_Objects.length >= 0;
/** The current size; */
private /*@spec_public@*/ int m_Size = 0;
//@ invariant 0 <= m_Size;
//@ invariant m_Size <= m_Objects.length;
/** The capacity increment */
private /*@spec_public@*/ int m_CapacityIncrement = 1;
//@ invariant 1 <= m_CapacityIncrement;
/** The capacity multiplier. */
private /*@spec_public@*/ int m_CapacityMultiplier = 2;
//@ invariant 1 <= m_CapacityMultiplier;
// Make sure the size will increase...
//@ invariant 3 <= m_CapacityMultiplier + m_CapacityIncrement;
/**
* Constructs an empty vector with initial
* capacity zero.
*/
public FastVector() {
m_Objects = new Object[0];
}
/**
* Constructs a vector with the given capacity.
*
* @param capacity the vector's initial capacity
*/
//@ requires capacity >= 0;
public FastVector(int capacity) {
m_Objects = new Object[capacity];
}
/**
* Adds an element to this vector. Increases its
* capacity if its not large enough.
*
* @param element the element to add
*/
public final void addElement(Object element) {
Object[] newObjects;
if (m_Size == m_Objects.length) {
newObjects = new Object[m_CapacityMultiplier *
(m_Objects.length +
m_CapacityIncrement)];
System.arraycopy(m_Objects, 0, newObjects, 0, m_Size);
m_Objects = newObjects;
}
m_Objects[m_Size] = element;
m_Size++;
}
/**
* Returns the capacity of the vector.
*
* @return the capacity of the vector
*/
//@ ensures \result == m_Objects.length;
public final /*@pure@*/ int capacity() {
return m_Objects.length;
}
/**
* Produces a shallow copy of this vector.
*
* @return the new vector
*/
public final Object copy() {
FastVector copy = new FastVector(m_Objects.length);
copy.m_Size = m_Size;
copy.m_CapacityIncrement = m_CapacityIncrement;
copy.m_CapacityMultiplier = m_CapacityMultiplier;
System.arraycopy(m_Objects, 0, copy.m_Objects, 0, m_Size);
return copy;
}
/**
* Clones the vector and shallow copies all its elements.
* The elements have to implement the Copyable interface.
*
* @return the new vector
*/
public final Object copyElements() {
FastVector copy = new FastVector(m_Objects.length);
copy.m_Size = m_Size;
copy.m_CapacityIncrement = m_CapacityIncrement;
copy.m_CapacityMultiplier = m_CapacityMultiplier;
for (int i = 0; i < m_Size; i++) {
copy.m_Objects[i] = ((Copyable)m_Objects[i]).copy();
}
return copy;
}
/**
* Returns the element at the given position.
*
* @param index the element's index
* @return the element with the given index
*/
//@ requires 0 <= index;
//@ requires index < m_Objects.length;
public final /*@pure@*/ Object elementAt(int index) {
return m_Objects[index];
}
/**
* Returns an enumeration of this vector.
*
* @return an enumeration of this vector
*/
public final /*@pure@*/ Enumeration elements() {
return new FastVectorEnumeration(this);
}
/**
* Returns an enumeration of this vector, skipping the
* element with the given index.
*
* @param index the element to skip
* @return an enumeration of this vector
*/
//@ requires 0 <= index && index < size();
public final /*@pure@*/ Enumeration elements(int index) {
return new FastVectorEnumeration(this, index);
}
/**
* added by akibriya
*/
public /*@pure@*/ boolean contains(Object o) {
if(o==null)
return false;
for(int i=0; i<m_Objects.length; i++)
if(o.equals(m_Objects[i]))
return true;
return false;
}
/**
* Returns the first element of the vector.
*
* @return the first element of the vector
*/
//@ requires m_Size > 0;
public final /*@pure@*/ Object firstElement() {
return m_Objects[0];
}
/**
* Searches for the first occurence of the given argument,
* testing for equality using the equals method.
*
* @param element the element to be found
* @return the index of the first occurrence of the argument
* in this vector; returns -1 if the object is not found
*/
public final /*@pure@*/ int indexOf(/*@non_null@*/ Object element) {
for (int i = 0; i < m_Size; i++) {
if (element.equals(m_Objects[i])) {
return i;
}
}
return -1;
}
/**
* Inserts an element at the given position.
*
* @param element the element to be inserted
* @param index the element's index
*/
public final void insertElementAt(Object element, int index) {
Object[] newObjects;
if (m_Size < m_Objects.length) {
System.arraycopy(m_Objects, index, m_Objects, index + 1,
m_Size - index);
m_Objects[index] = element;
} else {
newObjects = new Object[m_CapacityMultiplier *
(m_Objects.length +
m_CapacityIncrement)];
System.arraycopy(m_Objects, 0, newObjects, 0, index);
newObjects[index] = element;
System.arraycopy(m_Objects, index, newObjects, index + 1,
m_Size - index);
m_Objects = newObjects;
}
m_Size++;
}
/**
* Returns the last element of the vector.
*
* @return the last element of the vector
*/
//@ requires m_Size > 0;
public final /*@pure@*/ Object lastElement() {
return m_Objects[m_Size - 1];
}
/**
* Deletes an element from this vector.
*
* @param index the index of the element to be deleted
*/
//@ requires 0 <= index && index < m_Size;
public final void removeElementAt(int index) {
System.arraycopy(m_Objects, index + 1, m_Objects, index,
m_Size - index - 1);
m_Size--;
}
/**
* Removes all components from this vector and sets its
* size to zero.
*/
public final void removeAllElements() {
m_Objects = new Object[m_Objects.length];
m_Size = 0;
}
/**
* Appends all elements of the supplied vector to this vector.
*
* @param toAppend the FastVector containing elements to append.
*/
public final void appendElements(FastVector toAppend) {
setCapacity(size() + toAppend.size());
System.arraycopy(toAppend.m_Objects, 0, m_Objects, size(), toAppend.size());
m_Size = m_Objects.length;
}
/**
* Returns all the elements of this vector as an array
*
* @return an array containing all the elements of this vector
*/
public final Object [] toArray() {
Object [] newObjects = new Object[size()];
System.arraycopy(m_Objects, 0, newObjects, 0, size());
return newObjects;
}
/**
* Sets the vector's capacity to the given value.
*
* @param capacity the new capacity
*/
public final void setCapacity(int capacity) {
Object[] newObjects = new Object[capacity];
System.arraycopy(m_Objects, 0, newObjects, 0, Math.min(capacity, m_Size));
m_Objects = newObjects;
if (m_Objects.length < m_Size)
m_Size = m_Objects.length;
}
/**
* Sets the element at the given index.
*
* @param element the element to be put into the vector
* @param index the index at which the element is to be placed
*/
//@ requires 0 <= index && index < size();
public final void setElementAt(Object element, int index) {
m_Objects[index] = element;
}
/**
* Returns the vector's current size.
*
* @return the vector's current size
*/
//@ ensures \result == m_Size;
public final /*@pure@*/ int size() {
return m_Size;
}
/**
* Swaps two elements in the vector.
*
* @param first index of the first element
* @param second index of the second element
*/
//@ requires 0 <= first && first < size();
//@ requires 0 <= second && second < size();
public final void swap(int first, int second) {
Object help = m_Objects[first];
m_Objects[first] = m_Objects[second];
m_Objects[second] = help;
}
/**
* Sets the vector's capacity to its size.
*/
public final void trimToSize() {
Object[] newObjects = new Object[m_Size];
System.arraycopy(m_Objects, 0, newObjects, 0, m_Size);
m_Objects = newObjects;
}
}