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/**
* Combinatorics Library
* Copyright 2012 Dmytro Paukov [email protected]
*/
package org.paukov.combinatorics;
import java.util.Arrays;
import java.util.HashSet;
import java.util.Set;
/**
* This class represents a simple vector of elements of type int
*
* @author Dmytro Paukov
* @version 2.0
* @see IntegerGenerator
* @see IntegerFactory
*/
public class IntegerVector {
protected final int[] _vector;
/**
* Default constructor creates an empty vector
*
* Notes: Use the factory method
* IntegerFactory.createIntegerVector() to create an empty
* vector
*
* @see IntegerFactory
*/
public IntegerVector() {
this(0);
}
/**
* Default constructor creates the empty vector
*
* Notes: Use the factory method
* IntegerFactory.createIntegerVector() to create an empty
* vector
*
* @see IntegerFactory
*/
public IntegerVector(int size) {
_vector = new int[size];
}
/**
* Constructor from an array
*
* Notes: Use the factory method
* IntegerFactory.createIntegerVector() to create a vector from
* an array
*
* @param array Initial array to initialize the created vector
* @see IntegerFactory
*/
public IntegerVector(int[] array, int len) {
_vector = new int[len];
System.arraycopy(array, 0, _vector, 0, len);
}
/**
* Constructor from an integer array
*
* Notes: Use the factory method
* IntegerFactory.createIntegerVector() to create a vector from
* an array
*
* @param array Initial array to initialize the created vector
* @see IntegerFactory
*/
public IntegerVector(int[] array) {
this(array, array.length);
}
/**
* Copy constructor
*
* Notes: Use the factory method
* IntegerFactory.createIntegerVector() to create a vector from
* another vector
*
* @param vector Initial vector to initialize the created vector
*/
public IntegerVector(IntegerVector vector) {
_vector = new int[vector.getSize()];
System.arraycopy(vector._vector, 0, _vector, 0, vector.getSize());
}
/**
* Sets the value of the index-element
*/
public void setValue(int index, int value) {
_vector[index] = value;
}
/**
* Gets the value of the given index
*
* @return The value of the index element
*/
public int getValue(int index) {
return _vector[index];
}
/**
* Returns the size of the vector
*
* @return The size of the vector
*/
public int getSize() {
if (_vector == null) {
return 0;
}
return _vector.length;
}
/**
* This method detects duplicates in the vector
*
* @return true if the vector has duplicates, otherwise false
*/
public boolean hasDuplicates() {
if (_vector.length <= 1) {
return false;
}
Set set = new HashSet();
for (int i = 0; i < _vector.length; i++) {
set.add(_vector[i]);
}
return set.size() < _vector.length;
}
/**
* This method detects if the vector's elements are equal. For example, this
* method returns true for a vector (a, a, a) and false for a vector (a, b,
* a)
*
* @return True if the vector's elements are equal
*/
public boolean isAllElementsEqual() {
if (_vector.length == 0) {
return false;
}
if (_vector.length == 1) {
return true;
}
for (int i = 0; i < _vector.length - 1; i++) {
if (_vector[i] != _vector[i + 1]) {
return false;
}
}
return true;
}
/**
* Returns vector as a list of elements
*
* @return List of all elements
*/
public int[] getVector() {
return _vector;
}
/**
* Hash code of the vector
*
* @see java.lang.Object#hashCode()
*/
public int hashCode() {
final int prime = 31;
int result = 1;
result = prime * result
+ ((_vector == null) ? 0 : Arrays.hashCode(_vector));
return result;
}
/**
* Equals
*
* @see java.lang.Object#equals(java.lang.Object)
*/
@Override
public boolean equals(Object obj) {
if (this == obj) {
return true;
}
if (obj == null) {
return false;
}
if (getClass() != obj.getClass()) {
return false;
}
IntegerVector other = (IntegerVector) obj;
if (_vector == other._vector) {
return true;
}
if (_vector == null) {
return false;
}
if (other._vector == null) {
return false;
}
if (_vector.length != other._vector.length) {
return false;
}
for (int i = 0; i < _vector.length; i++) {
if (_vector[i] != other._vector[i]) {
return false;
}
}
return true;
}
/**
* Returns vector as a string
*
* @see java.lang.Object#toString()
*/
@Override
public String toString() {
StringBuilder sb = new StringBuilder();
sb.append("IntegerVector=([");
for (int i = 0; i < _vector.length; i++) {
sb.append(_vector[i]);
if (i < _vector.length - 1) {
sb.append(", ");
}
}
sb.append("], size=").append(getSize()).append(")");
return sb.toString();
}
}