org.eclipse.persistence.internal.identitymaps.CacheId Maven / Gradle / Ivy
Go to download
Show more of this group Show more artifacts with this name
Show all versions of eclipselink Show documentation
Show all versions of eclipselink Show documentation
EclipseLink build based upon Git transaction f2b9fc5
/*
* Copyright (c) 2011, 2021 Oracle and/or its affiliates. All rights reserved.
*
* This program and the accompanying materials are made available under the
* terms of the Eclipse Public License v. 2.0 which is available at
* http://www.eclipse.org/legal/epl-2.0,
* or the Eclipse Distribution License v. 1.0 which is available at
* http://www.eclipse.org/org/documents/edl-v10.php.
*
* SPDX-License-Identifier: EPL-2.0 OR BSD-3-Clause
*/
// Contributors:
// James Sutherland - initial API and implementation
package org.eclipse.persistence.internal.identitymaps;
import java.io.*;
import java.util.Arrays;
import org.eclipse.persistence.internal.helper.*;
/**
* Defines a wrapper for a primary key (Id) to use as a key in the cache.
*
* @since EclipseLink 2.1
* @author James Sutherland
*/
public class CacheId implements Serializable, Comparable {
public static final CacheId EMPTY = new CacheId(new Object[0]);
private static final CacheIdComparator COMPARATOR = new CacheIdComparator();
/** The primary key values. */
protected Object[] primaryKey;
/** Cached hashcode. */
protected int hash;
/** Indicates whether at least one element of primaryKey is array. */
protected boolean hasArray;
public CacheId() {
}
public CacheId(Object[] primaryKey) {
this.primaryKey = primaryKey;
this.hash = computeHash(primaryKey);
}
public Object[] getPrimaryKey() {
return primaryKey;
}
public void setPrimaryKey(Object[] primaryKey) {
this.primaryKey = primaryKey;
this.hash = computeHash(primaryKey);
}
/**
* Append the value to the end of the primary key values.
*/
public void add(Object value) {
Object[] array = new Object[this.primaryKey.length + 1];
System.arraycopy(this.primaryKey, 0, array, 0, this.primaryKey.length);
array[this.primaryKey.length] = value;
setPrimaryKey(array);
}
/**
* Set the value in the primary key values.
*/
public void set(int index, Object value) {
this.primaryKey[index] = value;
setPrimaryKey(this.primaryKey);
}
/**
* Pre-compute the hash to optimize hash calls.
*/
protected int computeHash(Object[] primaryKey) {
int result = 1;
for (Object value : primaryKey) {
if (value != null) {
//bug5709489, gf bug 1193: fix to handle array hashcodes properly
if (value.getClass().isArray()) {
result = computeArrayHashCode(result, value);
this.hasArray = true;
} else {
result = 31 * result + value.hashCode();
}
} else {
result = 31 * result;
}
}
return result;
}
/**
* Compute the hashcode for supported array types.
*/
private int computeArrayHashCode(int result, Object obj) {
if (obj.getClass() == ClassConstants.APBYTE) {
for (byte element : (byte[])obj) {
result = 31 * result + element;
}
} else if (obj.getClass() == ClassConstants.APCHAR) {
for (char element : (char[])obj) {
result = 31 * result + element;
}
} else {
for (Object element : (Object[])obj) {
result = 31 * result + (element == null ? 0 : element.hashCode());
}
}
return result;
}
/**
* Return the precomputed hashcode.
*/
@Override
public int hashCode() {
return this.hash;
}
/**
* Determine if the receiver is equal to anObject.
* If anObject is a CacheKey, do further comparison, otherwise, return false.
* @see CacheKey#equals(CacheKey)
*/
@Override
public boolean equals(Object object) {
try {
return equals((CacheId)object);
} catch (ClassCastException incorrectType) {
return false;
}
}
/**
* Determine if the receiver is equal to key.
* Use an index compare, because it is much faster than enumerations.
*/
public boolean equals(CacheId id) {
if (this == id) {
return true;
}
if (this.hash != id.hash) {
return false;
}
if (this.hasArray != id.hasArray) {
return false;
}
// PERF: Using direct variable access.
int size = this.primaryKey.length;
Object[] otherKey = id.primaryKey;
if (size == otherKey.length) {
for (int index = 0; index < size; index++) {
Object value = this.primaryKey[index];
Object otherValue = otherKey[index];
if (value == null) {
if (otherValue != null) {
return false;
} else {
continue;
}
} else if (otherValue == null) {
return false;
}
if (this.hasArray) {
Class valueClass = value.getClass();
if (valueClass.isArray()) {
Class otherClass = otherValue.getClass();
//gf bug 1193: fix array comparison logic to exit if they don't match, and continue the loop if they do
if (((valueClass == ClassConstants.APBYTE) && (otherClass == ClassConstants.APBYTE)) ) {
if (!Helper.compareByteArrays((byte[])value, (byte[])otherValue)){
return false;
}
} else if (((valueClass == ClassConstants.APCHAR) && (otherClass == ClassConstants.APCHAR)) ) {
if (!Helper.compareCharArrays((char[])value, (char[])otherValue)){
return false;
}
} else {
if (!Helper.compareArrays((Object[])value, (Object[])otherValue)) {
return false;
}
}
} else {
if (!(value.equals(otherValue))) {
return false;
}
}
} else {
if (!(value.equals(otherValue))) {
return false;
}
}
}
return true;
}
return false;
}
/**
* Determine if the receiver is greater or less than the key.
*/
@Override
public int compareTo(CacheId otherId) {
return COMPARATOR.compare(this, otherId);
}
public boolean hasArray() {
return this.hasArray;
}
@Override
public String toString() {
return "[" + Arrays.asList(this.primaryKey) + ": " + this.hash + "]";
}
}