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LANG-839 ArrayUtils removeElements methods use unnecessary HashSet 

Eliminate conversion of BitSet to int[]

git-svn-id: https://svn.apache.org/repos/asf/commons/proper/lang/trunk@1396075 13f79535-47bb-0310-9956-ffa450edef68
This commit is contained in:
Sebastian Bazley 2012-10-09 15:37:05 +00:00
parent 49685a4156
commit 8bbf8a9e2f
2 changed files with 42 additions and 55 deletions
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59
src/main/java/org/apache/commons/lang3/ArrayUtils.java
View File

@ -5020,7 +5020,7 @@ public static <T> T[] removeElements(T[] array, T... values) {
}
}
@SuppressWarnings("unchecked") // removeAll() always creates an array of the same type as its input
T[] result = (T[]) removeAll((Object)array, extractIndices(toRemove));
T[] result = (T[]) removeAll(array, toRemove);
return result;
}
@ -5110,7 +5110,7 @@ public static byte[] removeElements(byte[] array, byte... values) {
toRemove.set(found++);
}
}
return (byte[]) removeAll((Object)array, extractIndices(toRemove));
return (byte[]) removeAll(array, toRemove);
}
/**
@ -5199,7 +5199,7 @@ public static short[] removeElements(short[] array, short... values) {
toRemove.set(found++);
}
}
return (short[]) removeAll((Object)array, extractIndices(toRemove));
return (short[]) removeAll(array, toRemove);
}
/**
@ -5288,7 +5288,7 @@ public static int[] removeElements(int[] array, int... values) {
toRemove.set(found++);
}
}
return (int[]) removeAll((Object)array, extractIndices(toRemove));
return (int[]) removeAll(array, toRemove);
}
/**
@ -5377,7 +5377,7 @@ public static char[] removeElements(char[] array, char... values) {
toRemove.set(found++);
}
}
return (char[]) removeAll((Object)array, extractIndices(toRemove));
return (char[]) removeAll(array, toRemove);
}
/**
@ -5466,7 +5466,7 @@ public static long[] removeElements(long[] array, long... values) {
toRemove.set(found++);
}
}
return (long[]) removeAll((Object)array, extractIndices(toRemove));
return (long[]) removeAll(array, toRemove);
}
/**
@ -5555,7 +5555,7 @@ public static float[] removeElements(float[] array, float... values) {
toRemove.set(found++);
}
}
return (float[]) removeAll((Object)array, extractIndices(toRemove));
return (float[]) removeAll(array, toRemove);
}
/**
@ -5644,7 +5644,7 @@ public static double[] removeElements(double[] array, double... values) {
toRemove.set(found++);
}
}
return (double[]) removeAll((Object)array, extractIndices(toRemove));
return (double[]) removeAll(array, toRemove);
}
/**
@ -5729,7 +5729,7 @@ public static boolean[] removeElements(boolean[] array, boolean... values) {
toRemove.set(found++);
}
}
return (boolean[]) removeAll((Object)array, extractIndices(toRemove));
return (boolean[]) removeAll(array, toRemove);
}
/**
@ -5783,16 +5783,39 @@ static Object removeAll(Object array, int... indices) {
}
/**
* Extract a set of BitSet indices into an int[].
* @param coll Bitset
* @return int[]
* Removes multiple array elements specified by indices.
*
* @param array source
* @param indices to remove
* @return new array of same type minus elements specified by the set bits in {@code indices}
* @since 3.2
*/
private static int[] extractIndices(BitSet coll) {
int[] result = new int[coll.cardinality()];
int i = 0;
int j=0;
while((j=coll.nextSetBit(j)) != -1) {
result[i++] = j++;
// package protected for access by unit tests
static Object removeAll(Object array, BitSet indices) {
final int srcLength = ArrayUtils.getLength(array);
// No need to check maxIndex here, because method only currently called from removeElements()
// which guarantee to generate on;y valid bit entries.
// final int maxIndex = indices.length();
// if (maxIndex > srcLength) {
// throw new IndexOutOfBoundsException("Index: " + (maxIndex-1) + ", Length: " + srcLength);
// }
final int removals = indices.cardinality(); // true bits are items to remove
Object result = Array.newInstance(array.getClass().getComponentType(), srcLength - removals);
int srcIndex=0;
int destIndex=0;
int count;
int set;
while((set = indices.nextSetBit(srcIndex)) != -1){
count = set - srcIndex;
if (count > 0) {
System.arraycopy(array, srcIndex, result, destIndex, count);
destIndex += count;
}
srcIndex = indices.nextClearBit(set);
}
count = srcLength - srcIndex;
if (count > 0) {
System.arraycopy(array, srcIndex, result, destIndex, count);
}
return result;
}

38
src/test/java/org/apache/commons/lang3/HashSetvBitSetTest.java
View File

@ -16,7 +16,6 @@
*/
package org.apache.commons.lang3;
import java.lang.reflect.Array;
import java.util.BitSet;
import java.util.HashSet;
@ -146,7 +145,7 @@ private long timeBitSetRemoveAll(int[] array, BitSet toRemove) {
int[] output = new int[0];
long start = System.nanoTime();
for(int i = 0; i < LOOPS2; i++){
output = (int[]) removeAll(array, toRemove);
output = (int[]) ArrayUtils.removeAll(array, toRemove);
}
long end = System.nanoTime();
Assert.assertEquals(array.length-toRemove.cardinality(), output.length);
@ -165,39 +164,4 @@ private long timeExtractRemoveAll(int[] array, BitSet toRemove) {
return end - start;
}
/**
* Removes multiple array elements specified by indices.
*
* @param array source
* @param indices to remove
* @return new array of same type minus elements specified by the set bits in {@code indices}
* @since 3.2
*/
// package protected for access by unit tests
static Object removeAll(Object array, BitSet indices) {
final int srcLength = ArrayUtils.getLength(array);
final int maxIndex = indices.length();
if (maxIndex > srcLength) { // TODO necessary? Can check this when creating the BitSit
throw new IndexOutOfBoundsException("Index: " + (maxIndex-1) + ", Length: " + srcLength);
}
final int removals = indices.cardinality(); // true bits are items to remove
Object result = Array.newInstance(array.getClass().getComponentType(), srcLength - removals);
int srcIndex=0;
int destIndex=0;
int count;
int set;
while((set = indices.nextSetBit(srcIndex)) != -1){
count = set - srcIndex;
if (count > 0) {
System.arraycopy(array, srcIndex, result, destIndex, count);
destIndex += count;
}
srcIndex = indices.nextClearBit(set);
}
count = srcLength - srcIndex;
if (count > 0) {
System.arraycopy(array, srcIndex, result, destIndex, count);
}
return result;
}
}