org.elasticsearch.common.util.SlicedDoubleList Maven / Gradle / Ivy
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* Licensed to Elasticsearch under one or more contributor
* license agreements. See the NOTICE file distributed with
* this work for additional information regarding copyright
* ownership. Elasticsearch licenses this file to you under
* the Apache License, Version 2.0 (the "License"); you may
* not use this file except in compliance with the License.
* You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing,
* software distributed under the License is distributed on an
* "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
* KIND, either express or implied. See the License for the
* specific language governing permissions and limitations
* under the License.
*/
package org.elasticsearch.common.util;
import java.util.AbstractList;
import java.util.RandomAccess;
import org.apache.lucene.util.ArrayUtil;
import com.google.common.primitives.Doubles;
public final class SlicedDoubleList extends AbstractList implements RandomAccess {
public static final SlicedDoubleList EMPTY = new SlicedDoubleList(0);
public double[] values;
public int offset;
public int length;
public SlicedDoubleList(int capacity) {
this(new double[capacity], 0, capacity);
}
public SlicedDoubleList(double[] values, int offset, int length) {
this.values = values;
this.offset = offset;
this.length = length;
}
@Override
public int size() {
return length;
}
@Override
public boolean isEmpty() {
return size() == 0;
}
@Override
public Double get(int index) {
assert index < size();
return values[offset + index];
}
@Override
public boolean contains(Object target) {
// Overridden to prevent a ton of boxing
return (target instanceof Double)
&& indexOf(values, (Double) target, offset, offset+length) != -1;
}
@Override
public int indexOf(Object target) {
// Overridden to prevent a ton of boxing
if (target instanceof Double) {
int i = indexOf(values, (Double) target, offset, offset+length);
if (i >= 0) {
return i - offset;
}
}
return -1;
}
@Override
public int lastIndexOf(Object target) {
// Overridden to prevent a ton of boxing
if (target instanceof Double) {
int i = lastIndexOf(values, (Double) target, offset, offset+length);
if (i >= 0) {
return i - offset;
}
}
return -1;
}
@Override
public Double set(int index, Double element) {
throw new UnsupportedOperationException("modifying list opertations are not implemented");
}
@Override
public boolean equals(Object object) {
if (object == this) {
return true;
}
if (object instanceof SlicedDoubleList) {
SlicedDoubleList that = (SlicedDoubleList) object;
int size = size();
if (that.size() != size) {
return false;
}
for (int i = 0; i < size; i++) {
if (values[offset + i] != that.values[that.offset + i]) {
return false;
}
}
return true;
}
return super.equals(object);
}
@Override
public int hashCode() {
int result = 1;
for (int i = 0; i < length; i++) {
result = 31 * result + Doubles.hashCode(values[offset+i]);
}
return result;
}
@Override
public String toString() {
StringBuilder builder = new StringBuilder(size() * 10);
builder.append('[');
if (length > 0) {
builder.append(values[offset]);
for (int i = 1; i < length; i++) {
builder.append(", ").append(values[offset+i]);
}
}
return builder.append(']').toString();
}
private static int indexOf(double[] array, double target, int start, int end) {
for (int i = start; i < end; i++) {
if (array[i] == target) {
return i;
}
}
return -1;
}
private static int lastIndexOf(double[] array, double target, int start, int end) {
for (int i = end - 1; i >= start; i--) {
if (array[i] == target) {
return i;
}
}
return -1;
}
public void grow(int newLength) {
assert offset == 0;
values = ArrayUtil.grow(values, newLength);
}
}