Acts like an java.util.ArrayList but for primitive int values
/*
* IntList.java Created Aug 310, 2010 by Andrew Butler, PSL
*/
//package prisms.util;
/**
* Acts like an {@link java.util.ArrayList} but for primitive int values
*/
public class IntList {
private int[] theValue;
private int theSize;
/**
* Creates a list with a capacity of 5
*/
public IntList() {
this(5);
}
/**
* Creates a list with a set capacity
*
* @param size
* The initial capacity of the list
*/
public IntList(int size) {
theValue = new int[size];
}
/**
* Creates a list with a set of values
*
* @param values
* The values for the list
*/
public IntList(int[] values) {
theValue = values;
theSize = values.length;
}
/**
* @return The number of elements in the list
*/
public int size() {
return theSize;
}
/**
* @return Whether this list is empty of elements
*/
public boolean isEmpty() {
return theSize == 0;
}
/**
* Clears this list, setting its size to 0
*/
public void clear() {
theSize = 0;
}
/**
* Gets the value in the list at the given index
*
* @param index
* The index of the value to get
* @return The value at the given index
*/
public int get(int index) {
if (index < 0 || index >= theSize)
throw new ArrayIndexOutOfBoundsException(index);
return theValue[index];
}
/**
* Adds a value to the end of this list
*
* @param value
* The value to add to the list
*/
public void add(int value) {
ensureCapacity(theSize + 1);
theValue[theSize++] = value;
}
/**
* Adds a value to this list at the given index
*
* @param index
* The index to add the value at
* @param value
* The value to add to the list
*/
public void add(int index, int value) {
if (index < 0 || index > theSize)
throw new ArrayIndexOutOfBoundsException(index);
ensureCapacity(theSize + 1);
for (int i = theSize; i > index; i--)
theValue[i] = theValue[i - 1];
theValue[index] = value;
theSize++;
}
/**
* Adds an array of values to the end of this list
*
* @param value
* The values to add
*/
public void addAll(int[] value) {
ensureCapacity(theSize + value.length);
for (int i = 0; i < value.length; i++)
theValue[theSize + i] = value[i];
theSize += value.length;
}
/**
* Adds a list of values to the end of this list
*
* @param list
* The list of values to add
*/
public void addAll(IntList list) {
ensureCapacity(theSize + list.theSize);
for (int i = 0; i < list.theSize; i++)
theValue[theSize + i] = list.theValue[i];
theSize += list.theSize;
}
/**
* Replaces a value in this list with another value
*
* @param index
* The index of the value to replace
* @param value
* The value to replace the old value with
* @return The old value at the given index
*/
public int set(int index, int value) {
if (index < 0 || index >= theSize)
throw new ArrayIndexOutOfBoundsException(index);
int ret = theValue[index];
theValue[index] = value;
return ret;
}
/**
* Removes a value from this list
*
* @param index
* The index of the value to remove
* @return The value that was removed
*/
public int remove(int index) {
if (index < 0 || index >= theSize)
throw new ArrayIndexOutOfBoundsException(index);
int ret = theValue[index];
for (int i = index; i < theSize - 1; i++)
theValue[i] = theValue[i + 1];
theSize--;
return ret;
}
/**
* Removes a value from this list
*
* @param value
* The value to remove
* @return Whether the value was found and removed
*/
public boolean removeValue(int value) {
for (int i = 0; i < theSize; i++)
if (theValue[i] == value) {
remove(i);
return true;
}
return false;
}
/**
* Removes all instances of the given value from this list
*
* @param value
* The value to remove
* @return The number of times the value was removed
*/
public int removeAll(int value) {
int ret = 0;
for (int i = 0; i < theSize; i++)
if (theValue[i] == value) {
remove(i);
i--;
ret++;
}
return ret;
}
/**
* Determines if this list contains a given value
*
* @param value
* The value to find
* @return Whether this list contains the given value
*/
public boolean contains(int value) {
return indexOf(value) >= 0;
}
/**
* Counts the number of times a value is represented in this list
*
* @param value
* The value to count
* @return The number of times the value appears in this list
*/
public int instanceCount(int value) {
int ret = 0;
for (int i = 0; i < theSize; i++)
if (theValue[i] == value)
ret++;
return ret;
}
/**
* Finds a value in this list
*
* @param value
* The value to find
* @return The first index whose value is the given value
*/
public int indexOf(int value) {
for (int i = 0; i < theSize; i++)
if (theValue[i] == value)
return i;
return -1;
}
/**
* Finds a value in this list
*
* @param value
* The value to find
* @return The last index whose value is the given value
*/
public int lastIndexOf(int value) {
for (int i = theSize - 1; i >= 0; i--)
if (theValue[i] == value)
return i;
return -1;
}
/**
* @return The list of values currently in this list
*/
public int[] toArray() {
int[] ret = new int[theSize];
System.arraycopy(theValue, 0, ret, 0, theSize);
return ret;
}
/**
* Similary to {@link #toArray()} but creates an array of {@link Integer}
* wrappers
*
* @return The list of values currently in this list
*/
public Integer[] toObjectArray() {
Integer[] ret = new Integer[theSize];
for (int i = 0; i < ret.length; i++)
ret[i] = new Integer(theValue[i]);
return ret;
}
/**
* Trims this list so that it wastes no space and its capacity is equal to
* its size
*/
public void trimToSize() {
if (theValue.length == theSize)
return;
int[] oldData = theValue;
theValue = new int[theSize];
System.arraycopy(oldData, 0, theValue, 0, theSize);
}
/**
* Ensures that this list's capacity is at list the given value
*
* @param minCapacity
* The minimum capacity for the list
*/
public void ensureCapacity(int minCapacity) {
int oldCapacity = theValue.length;
if (minCapacity > oldCapacity) {
int oldData[] = theValue;
int newCapacity = (oldCapacity * 3) / 2 + 1;
if (newCapacity < minCapacity)
newCapacity = minCapacity;
theValue = new int[newCapacity];
System.arraycopy(oldData, 0, theValue, 0, theSize);
}
}
}
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