org.apache.lucene.util.IntsRef Maven / Gradle / Ivy
Show all versions of org.apache.servicemix.bundles.lucene
/*
* Licensed to the Apache Software Foundation (ASF) under one or more
* contributor license agreements. See the NOTICE file distributed with
* this work for additional information regarding copyright ownership.
* The ASF 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.apache.lucene.util;
import java.util.Arrays;
/**
* Represents int[], as a slice (offset + length) into an existing int[]. The {@link #ints} member
* should never be null; use {@link #EMPTY_INTS} if necessary.
*
* @lucene.internal
*/
public final class IntsRef implements Comparable, Cloneable {
/** An empty integer array for convenience */
public static final int[] EMPTY_INTS = new int[0];
/** The contents of the IntsRef. Should never be {@code null}. */
public int[] ints;
/** Offset of first valid integer. */
public int offset;
/** Length of used ints. */
public int length;
/** Create a IntsRef with {@link #EMPTY_INTS} */
public IntsRef() {
ints = EMPTY_INTS;
}
/**
* Create a IntsRef pointing to a new array of size capacity. Offset and length will
* both be zero.
*/
public IntsRef(int capacity) {
ints = new int[capacity];
}
/** This instance will directly reference ints w/o making a copy. ints should not be null. */
public IntsRef(int[] ints, int offset, int length) {
this.ints = ints;
this.offset = offset;
this.length = length;
assert isValid();
}
/**
* Returns a shallow clone of this instance (the underlying ints are not copied and will be
* shared by both the returned object and this object.
*
* @see #deepCopyOf
*/
@Override
public IntsRef clone() {
return new IntsRef(ints, offset, length);
}
@Override
public int hashCode() {
final int prime = 31;
int result = 0;
final int end = offset + length;
for (int i = offset; i < end; i++) {
result = prime * result + ints[i];
}
return result;
}
@Override
public boolean equals(Object other) {
if (other == null) {
return false;
}
if (other instanceof IntsRef) {
return this.intsEquals((IntsRef) other);
}
return false;
}
public boolean intsEquals(IntsRef other) {
return Arrays.equals(
this.ints,
this.offset,
this.offset + this.length,
other.ints,
other.offset,
other.offset + other.length);
}
/** Signed int order comparison */
@Override
public int compareTo(IntsRef other) {
return Arrays.compare(
this.ints,
this.offset,
this.offset + this.length,
other.ints,
other.offset,
other.offset + other.length);
}
@Override
public String toString() {
StringBuilder sb = new StringBuilder();
sb.append('[');
final int end = offset + length;
for (int i = offset; i < end; i++) {
if (i > offset) {
sb.append(' ');
}
sb.append(Integer.toHexString(ints[i]));
}
sb.append(']');
return sb.toString();
}
/**
* Creates a new IntsRef that points to a copy of the ints from other
*
* The returned IntsRef will have a length of other.length and an offset of zero.
*/
public static IntsRef deepCopyOf(IntsRef other) {
return new IntsRef(
ArrayUtil.copyOfSubArray(other.ints, other.offset, other.offset + other.length),
0,
other.length);
}
/** Performs internal consistency checks. Always returns true (or throws IllegalStateException) */
public boolean isValid() {
if (ints == null) {
throw new IllegalStateException("ints is null");
}
if (length < 0) {
throw new IllegalStateException("length is negative: " + length);
}
if (length > ints.length) {
throw new IllegalStateException(
"length is out of bounds: " + length + ",ints.length=" + ints.length);
}
if (offset < 0) {
throw new IllegalStateException("offset is negative: " + offset);
}
if (offset > ints.length) {
throw new IllegalStateException(
"offset out of bounds: " + offset + ",ints.length=" + ints.length);
}
if (offset + length < 0) {
throw new IllegalStateException(
"offset+length is negative: offset=" + offset + ",length=" + length);
}
if (offset + length > ints.length) {
throw new IllegalStateException(
"offset+length out of bounds: offset="
+ offset
+ ",length="
+ length
+ ",ints.length="
+ ints.length);
}
return true;
}
}