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	/*
	* 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.commons.lang3.builder;

	import java.lang.reflect.AccessibleObject;
	import java.lang.reflect.Field;
	import java.lang.reflect.Modifier;
	import java.util.Collection;
	import java.util.Comparator;
	import java.util.Objects;

	import org.apache.commons.lang3.ArrayUtils;

	/**
	* Assists in implementing {@link java.lang.Comparable#compareTo(Object)} methods.
	*
	* <p>It is consistent with {@code equals(Object)} and
	* {@code hashcode()} built with {@link EqualsBuilder} and
	* {@link HashCodeBuilder}.</p>
	*
	* <p>Two Objects that compare equal using {@code equals(Object)} should normally
	* also compare equal using {@code compareTo(Object)}.</p>
	*
	* <p>All relevant fields should be included in the calculation of the
	* comparison. Derived fields may be ignored. The same fields, in the same
	* order, should be used in both {@code compareTo(Object)} and
	* {@code equals(Object)}.</p>
	*
	* <p>To use this class write code as follows:</p>
	*
	* <pre>
	* public class MyClass {
	* String field1;
	* int field2;
	* boolean field3;
	*
	* ...
	*
	* public int compareTo(Object o) {
	* MyClass myClass = (MyClass) o;
	* return new CompareToBuilder()
	* .appendSuper(super.compareTo(o)
	* .append(this.field1, myClass.field1)
	* .append(this.field2, myClass.field2)
	* .append(this.field3, myClass.field3)
	* .toComparison();
	* }
	* }
	* </pre>
	*
	* <p>Values are compared in the order they are appended to the builder. If any comparison returns
	* a non-zero result, then that value will be the result returned by {@code toComparison()} and all
	* subsequent comparisons are skipped.</p>
	*
	* <p>Alternatively, there are {@link #reflectionCompare(Object, Object) reflectionCompare} methods that use
	* reflection to determine the fields to append. Because fields can be private,
	* {@code reflectionCompare} uses {@link java.lang.reflect.AccessibleObject#setAccessible(boolean)} to
	* bypass normal access control checks. This will fail under a security manager,
	* unless the appropriate permissions are set up correctly. It is also
	* slower than appending explicitly.</p>
	*
	* <p>A typical implementation of {@code compareTo(Object)} using
	* {@code reflectionCompare} looks like:</p>

	* <pre>
	* public int compareTo(Object o) {
	* return CompareToBuilder.reflectionCompare(this, o);
	* }
	* </pre>
	*
	* <p>The reflective methods compare object fields in the order returned by
	* {@link Class#getDeclaredFields()}. The fields of the class are compared first, followed by those
	* of its parent classes (in order from the bottom to the top of the class hierarchy).</p>
	*
	* @see java.lang.Comparable
	* @see java.lang.Object#equals(Object)
	* @see java.lang.Object#hashCode()
	* @see EqualsBuilder
	* @see HashCodeBuilder
	* @since 1.0
	*/
	public class CompareToBuilder implements Builder<Integer> {

	/**
	* Current state of the comparison as appended fields are checked.
	*/
	private int comparison;

	/**
	* <p>Constructor for CompareToBuilder.</p>
	*
	* <p>Starts off assuming that the objects are equal. Multiple calls are
	* then made to the various append methods, followed by a call to
	* {@link #toComparison} to get the result.</p>
	*/
	public CompareToBuilder() {
	super();
	comparison = 0;
	}

	//-----------------------------------------------------------------------
	/**
	* <p>Compares two {@code Object}s via reflection.</p>
	*
	* <p>Fields can be private, thus {@code AccessibleObject.setAccessible}
	* is used to bypass normal access control checks. This will fail under a
	* security manager unless the appropriate permissions are set.</p>
	*
	* <ul>
	* <li>Static fields will not be compared</li>
	* <li>Transient members will be not be compared, as they are likely derived
	* fields</li>
	* <li>Superclass fields will be compared</li>
	* </ul>
	*
	* <p>If both {@code lhs} and {@code rhs} are {@code null},
	* they are considered equal.</p>
	*
	* @param lhs left-hand object
	* @param rhs right-hand object
	* @return a negative integer, zero, or a positive integer as {@code lhs}
	* is less than, equal to, or greater than {@code rhs}
	* @throws NullPointerException if either (but not both) parameters are
	* {@code null}
	* @throws ClassCastException if {@code rhs} is not assignment-compatible
	* with {@code lhs}
	*/
	public static int reflectionCompare(final Object lhs, final Object rhs) {
	return reflectionCompare(lhs, rhs, false, null);
	}

	/**
	* <p>Compares two {@code Object}s via reflection.</p>
	*
	* <p>Fields can be private, thus {@code AccessibleObject.setAccessible}
	* is used to bypass normal access control checks. This will fail under a
	* security manager unless the appropriate permissions are set.</p>
	*
	* <ul>
	* <li>Static fields will not be compared</li>
	* <li>If {@code compareTransients} is {@code true},
	* compares transient members. Otherwise ignores them, as they
	* are likely derived fields.</li>
	* <li>Superclass fields will be compared</li>
	* </ul>
	*
	* <p>If both {@code lhs} and {@code rhs} are {@code null},
	* they are considered equal.</p>
	*
	* @param lhs left-hand object
	* @param rhs right-hand object
	* @param compareTransients whether to compare transient fields
	* @return a negative integer, zero, or a positive integer as {@code lhs}
	* is less than, equal to, or greater than {@code rhs}
	* @throws NullPointerException if either {@code lhs} or {@code rhs}
	* (but not both) is {@code null}
	* @throws ClassCastException if {@code rhs} is not assignment-compatible
	* with {@code lhs}
	*/
	public static int reflectionCompare(final Object lhs, final Object rhs, final boolean compareTransients) {
	return reflectionCompare(lhs, rhs, compareTransients, null);
	}

	/**
	* <p>Compares two {@code Object}s via reflection.</p>
	*
	* <p>Fields can be private, thus {@code AccessibleObject.setAccessible}
	* is used to bypass normal access control checks. This will fail under a
	* security manager unless the appropriate permissions are set.</p>
	*
	* <ul>
	* <li>Static fields will not be compared</li>
	* <li>If {@code compareTransients} is {@code true},
	* compares transient members. Otherwise ignores them, as they
	* are likely derived fields.</li>
	* <li>Superclass fields will be compared</li>
	* </ul>
	*
	* <p>If both {@code lhs} and {@code rhs} are {@code null},
	* they are considered equal.</p>
	*
	* @param lhs left-hand object
	* @param rhs right-hand object
	* @param excludeFields Collection of String fields to exclude
	* @return a negative integer, zero, or a positive integer as {@code lhs}
	* is less than, equal to, or greater than {@code rhs}
	* @throws NullPointerException if either {@code lhs} or {@code rhs}
	* (but not both) is {@code null}
	* @throws ClassCastException if {@code rhs} is not assignment-compatible
	* with {@code lhs}
	* @since 2.2
	*/
	public static int reflectionCompare(final Object lhs, final Object rhs, final Collection<String> excludeFields) {
	return reflectionCompare(lhs, rhs, ReflectionToStringBuilder.toNoNullStringArray(excludeFields));
	}

	/**
	* <p>Compares two {@code Object}s via reflection.</p>
	*
	* <p>Fields can be private, thus {@code AccessibleObject.setAccessible}
	* is used to bypass normal access control checks. This will fail under a
	* security manager unless the appropriate permissions are set.</p>
	*
	* <ul>
	* <li>Static fields will not be compared</li>
	* <li>If {@code compareTransients} is {@code true},
	* compares transient members. Otherwise ignores them, as they
	* are likely derived fields.</li>
	* <li>Superclass fields will be compared</li>
	* </ul>
	*
	* <p>If both {@code lhs} and {@code rhs} are {@code null},
	* they are considered equal.</p>
	*
	* @param lhs left-hand object
	* @param rhs right-hand object
	* @param excludeFields array of fields to exclude
	* @return a negative integer, zero, or a positive integer as {@code lhs}
	* is less than, equal to, or greater than {@code rhs}
	* @throws NullPointerException if either {@code lhs} or {@code rhs}
	* (but not both) is {@code null}
	* @throws ClassCastException if {@code rhs} is not assignment-compatible
	* with {@code lhs}
	* @since 2.2
	*/
	public static int reflectionCompare(final Object lhs, final Object rhs, final String... excludeFields) {
	return reflectionCompare(lhs, rhs, false, null, excludeFields);
	}

	/**
	* <p>Compares two {@code Object}s via reflection.</p>
	*
	* <p>Fields can be private, thus {@code AccessibleObject.setAccessible}
	* is used to bypass normal access control checks. This will fail under a
	* security manager unless the appropriate permissions are set.</p>
	*
	* <ul>
	* <li>Static fields will not be compared</li>
	* <li>If the {@code compareTransients} is {@code true},
	* compares transient members. Otherwise ignores them, as they
	* are likely derived fields.</li>
	* <li>Compares superclass fields up to and including {@code reflectUpToClass}.
	* If {@code reflectUpToClass} is {@code null}, compares all superclass fields.</li>
	* </ul>
	*
	* <p>If both {@code lhs} and {@code rhs} are {@code null},
	* they are considered equal.</p>
	*
	* @param lhs left-hand object
	* @param rhs right-hand object
	* @param compareTransients whether to compare transient fields
	* @param reflectUpToClass last superclass for which fields are compared
	* @param excludeFields fields to exclude
	* @return a negative integer, zero, or a positive integer as {@code lhs}
	* is less than, equal to, or greater than {@code rhs}
	* @throws NullPointerException if either {@code lhs} or {@code rhs}
	* (but not both) is {@code null}
	* @throws ClassCastException if {@code rhs} is not assignment-compatible
	* with {@code lhs}
	* @since 2.2 (2.0 as {@code reflectionCompare(Object, Object, boolean, Class)})
	*/
	public static int reflectionCompare(
	final Object lhs,
	final Object rhs,
	final boolean compareTransients,
	final Class<?> reflectUpToClass,
	final String... excludeFields) {

	if (lhs == rhs) {
	return 0;
	}
	Objects.requireNonNull(lhs, "lhs");
	Objects.requireNonNull(rhs, "rhs");

	Class<?> lhsClazz = lhs.getClass();
	if (!lhsClazz.isInstance(rhs)) {
	throw new ClassCastException();
	}
	final CompareToBuilder compareToBuilder = new CompareToBuilder();
	reflectionAppend(lhs, rhs, lhsClazz, compareToBuilder, compareTransients, excludeFields);
	while (lhsClazz.getSuperclass() != null && lhsClazz != reflectUpToClass) {
	lhsClazz = lhsClazz.getSuperclass();
	reflectionAppend(lhs, rhs, lhsClazz, compareToBuilder, compareTransients, excludeFields);
	}
	return compareToBuilder.toComparison();
	}

	/**
	* <p>Appends to {@code builder} the comparison of {@code lhs}
	* to {@code rhs} using the fields defined in {@code clazz}.</p>
	*
	* @param lhs left-hand object
	* @param rhs right-hand object
	* @param clazz {@code Class} that defines fields to be compared
	* @param builder {@code CompareToBuilder} to append to
	* @param useTransients whether to compare transient fields
	* @param excludeFields fields to exclude
	*/
	private static void reflectionAppend(
	final Object lhs,
	final Object rhs,
	final Class<?> clazz,
	final CompareToBuilder builder,
	final boolean useTransients,
	final String[] excludeFields) {

	final Field[] fields = clazz.getDeclaredFields();
	AccessibleObject.setAccessible(fields, true);
	for (int i = 0; i < fields.length && builder.comparison == 0; i++) {
	final Field f = fields[i];
	if (!ArrayUtils.contains(excludeFields, f.getName())
	&& !f.getName().contains("$")
	&& (useTransients \|\| !Modifier.isTransient(f.getModifiers()))
	&& !Modifier.isStatic(f.getModifiers())) {
	try {
	builder.append(f.get(lhs), f.get(rhs));
	} catch (final IllegalAccessException e) {
	// This can't happen. Would get a Security exception instead.
	// Throw a runtime exception in case the impossible happens.
	throw new InternalError("Unexpected IllegalAccessException");
	}
	}
	}
	}

	//-----------------------------------------------------------------------
	/**
	* <p>Appends to the {@code builder} the {@code compareTo(Object)}
	* result of the superclass.</p>
	*
	* @param superCompareTo result of calling {@code super.compareTo(Object)}
	* @return this - used to chain append calls
	* @since 2.0
	*/
	public CompareToBuilder appendSuper(final int superCompareTo) {
	if (comparison != 0) {
	return this;
	}
	comparison = superCompareTo;
	return this;
	}

	//-----------------------------------------------------------------------
	/**
	* <p>Appends to the {@code builder} the comparison of
	* two {@code Object}s.</p>
	*
	* <ol>
	* <li>Check if {@code lhs == rhs}</li>
	* <li>Check if either {@code lhs} or {@code rhs} is {@code null},
	* a {@code null} object is less than a non-{@code null} object</li>
	* <li>Check the object contents</li>
	* </ol>
	*
	* <p>{@code lhs} must either be an array or implement {@link Comparable}.</p>
	*
	* @param lhs left-hand object
	* @param rhs right-hand object
	* @return this - used to chain append calls
	* @throws ClassCastException if {@code rhs} is not assignment-compatible
	* with {@code lhs}
	*/
	public CompareToBuilder append(final Object lhs, final Object rhs) {
	return append(lhs, rhs, null);
	}

	/**
	* <p>Appends to the {@code builder} the comparison of
	* two {@code Object}s.</p>
	*
	* <ol>
	* <li>Check if {@code lhs == rhs}</li>
	* <li>Check if either {@code lhs} or {@code rhs} is {@code null},
	* a {@code null} object is less than a non-{@code null} object</li>
	* <li>Check the object contents</li>
	* </ol>
	*
	* <p>If {@code lhs} is an array, array comparison methods will be used.
	* Otherwise {@code comparator} will be used to compare the objects.
	* If {@code comparator} is {@code null}, {@code lhs} must
	* implement {@link Comparable} instead.</p>
	*
	* @param lhs left-hand object
	* @param rhs right-hand object
	* @param comparator {@code Comparator} used to compare the objects,
	* {@code null} means treat lhs as {@code Comparable}
	* @return this - used to chain append calls
	* @throws ClassCastException if {@code rhs} is not assignment-compatible
	* with {@code lhs}
	* @since 2.0
	*/
	public CompareToBuilder append(final Object lhs, final Object rhs, final Comparator<?> comparator) {
	if (comparison != 0) {
	return this;
	}
	if (lhs == rhs) {
	return this;
	}
	if (lhs == null) {
	comparison = -1;
	return this;
	}
	if (rhs == null) {
	comparison = 1;
	return this;
	}
	if (lhs.getClass().isArray()) {
	// factor out array case in order to keep method small enough to be inlined
	appendArray(lhs, rhs, comparator);
	} else {
	// the simple case, not an array, just test the element
	if (comparator == null) {
	@SuppressWarnings("unchecked") // assume this can be done; if not throw CCE as per Javadoc
	final Comparable<Object> comparable = (Comparable<Object>) lhs;
	comparison = comparable.compareTo(rhs);
	} else {
	@SuppressWarnings("unchecked") // assume this can be done; if not throw CCE as per Javadoc
	final Comparator<Object> comparator2 = (Comparator<Object>) comparator;
	comparison = comparator2.compare(lhs, rhs);
	}
	}
	return this;
	}

	private void appendArray(final Object lhs, final Object rhs, final Comparator<?> comparator) {
	// switch on type of array, to dispatch to the correct handler
	// handles multi dimensional arrays
	// throws a ClassCastException if rhs is not the correct array type
	if (lhs instanceof long[]) {
	append((long[]) lhs, (long[]) rhs);
	} else if (lhs instanceof int[]) {
	append((int[]) lhs, (int[]) rhs);
	} else if (lhs instanceof short[]) {
	append((short[]) lhs, (short[]) rhs);
	} else if (lhs instanceof char[]) {
	append((char[]) lhs, (char[]) rhs);
	} else if (lhs instanceof byte[]) {
	append((byte[]) lhs, (byte[]) rhs);
	} else if (lhs instanceof double[]) {
	append((double[]) lhs, (double[]) rhs);
	} else if (lhs instanceof float[]) {
	append((float[]) lhs, (float[]) rhs);
	} else if (lhs instanceof boolean[]) {
	append((boolean[]) lhs, (boolean[]) rhs);
	} else {
	// not an array of primitives
	// throws a ClassCastException if rhs is not an array
	append((Object[]) lhs, (Object[]) rhs, comparator);
	}
	}

	//-------------------------------------------------------------------------
	/**
	* Appends to the {@code builder} the comparison of
	* two {@code long}s.
	*
	* @param lhs left-hand value
	* @param rhs right-hand value
	* @return this - used to chain append calls
	*/
	public CompareToBuilder append(final long lhs, final long rhs) {
	if (comparison != 0) {
	return this;
	}
	comparison = Long.compare(lhs, rhs);
	return this;
	}

	/**
	* Appends to the {@code builder} the comparison of
	* two {@code int}s.
	*
	* @param lhs left-hand value
	* @param rhs right-hand value
	* @return this - used to chain append calls
	*/
	public CompareToBuilder append(final int lhs, final int rhs) {
	if (comparison != 0) {
	return this;
	}
	comparison = Integer.compare(lhs, rhs);
	return this;
	}

	/**
	* Appends to the {@code builder} the comparison of
	* two {@code short}s.
	*
	* @param lhs left-hand value
	* @param rhs right-hand value
	* @return this - used to chain append calls
	*/
	public CompareToBuilder append(final short lhs, final short rhs) {
	if (comparison != 0) {
	return this;
	}
	comparison = Short.compare(lhs, rhs);
	return this;
	}

	/**
	* Appends to the {@code builder} the comparison of
	* two {@code char}s.
	*
	* @param lhs left-hand value
	* @param rhs right-hand value
	* @return this - used to chain append calls
	*/
	public CompareToBuilder append(final char lhs, final char rhs) {
	if (comparison != 0) {
	return this;
	}
	comparison = Character.compare(lhs, rhs);
	return this;
	}

	/**
	* Appends to the {@code builder} the comparison of
	* two {@code byte}s.
	*
	* @param lhs left-hand value
	* @param rhs right-hand value
	* @return this - used to chain append calls
	*/
	public CompareToBuilder append(final byte lhs, final byte rhs) {
	if (comparison != 0) {
	return this;
	}
	comparison = Byte.compare(lhs, rhs);
	return this;
	}

	/**
	* <p>Appends to the {@code builder} the comparison of
	* two {@code double}s.</p>
	*
	* <p>This handles NaNs, Infinities, and {@code -0.0}.</p>
	*
	* <p>It is compatible with the hash code generated by
	* {@code HashCodeBuilder}.</p>
	*
	* @param lhs left-hand value
	* @param rhs right-hand value
	* @return this - used to chain append calls
	*/
	public CompareToBuilder append(final double lhs, final double rhs) {
	if (comparison != 0) {
	return this;
	}
	comparison = Double.compare(lhs, rhs);
	return this;
	}

	/**
	* <p>Appends to the {@code builder} the comparison of
	* two {@code float}s.</p>
	*
	* <p>This handles NaNs, Infinities, and {@code -0.0}.</p>
	*
	* <p>It is compatible with the hash code generated by
	* {@code HashCodeBuilder}.</p>
	*
	* @param lhs left-hand value
	* @param rhs right-hand value
	* @return this - used to chain append calls
	*/
	public CompareToBuilder append(final float lhs, final float rhs) {
	if (comparison != 0) {
	return this;
	}
	comparison = Float.compare(lhs, rhs);
	return this;
	}

	/**
	* Appends to the {@code builder} the comparison of
	* two {@code booleans}s.
	*
	* @param lhs left-hand value
	* @param rhs right-hand value
	* @return this - used to chain append calls
	*/
	public CompareToBuilder append(final boolean lhs, final boolean rhs) {
	if (comparison != 0) {
	return this;
	}
	if (lhs == rhs) {
	return this;
	}
	if (lhs) {
	comparison = 1;
	} else {
	comparison = -1;
	}
	return this;
	}

	//-----------------------------------------------------------------------
	/**
	* <p>Appends to the {@code builder} the deep comparison of
	* two {@code Object} arrays.</p>
	*
	* <ol>
	* <li>Check if arrays are the same using {@code ==}</li>
	* <li>Check if for {@code null}, {@code null} is less than non-{@code null}</li>
	* <li>Check array length, a short length array is less than a long length array</li>
	* <li>Check array contents element by element using {@link #append(Object, Object, Comparator)}</li>
	* </ol>
	*
	* <p>This method will also will be called for the top level of multi-dimensional,
	* ragged, and multi-typed arrays.</p>
	*
	* @param lhs left-hand array
	* @param rhs right-hand array
	* @return this - used to chain append calls
	* @throws ClassCastException if {@code rhs} is not assignment-compatible
	* with {@code lhs}
	*/
	public CompareToBuilder append(final Object[] lhs, final Object[] rhs) {
	return append(lhs, rhs, null);
	}

	/**
	* <p>Appends to the {@code builder} the deep comparison of
	* two {@code Object} arrays.</p>
	*
	* <ol>
	* <li>Check if arrays are the same using {@code ==}</li>
	* <li>Check if for {@code null}, {@code null} is less than non-{@code null}</li>
	* <li>Check array length, a short length array is less than a long length array</li>
	* <li>Check array contents element by element using {@link #append(Object, Object, Comparator)}</li>
	* </ol>
	*
	* <p>This method will also will be called for the top level of multi-dimensional,
	* ragged, and multi-typed arrays.</p>
	*
	* @param lhs left-hand array
	* @param rhs right-hand array
	* @param comparator {@code Comparator} to use to compare the array elements,
	* {@code null} means to treat {@code lhs} elements as {@code Comparable}.
	* @return this - used to chain append calls
	* @throws ClassCastException if {@code rhs} is not assignment-compatible
	* with {@code lhs}
	* @since 2.0
	*/
	public CompareToBuilder append(final Object[] lhs, final Object[] rhs, final Comparator<?> comparator) {
	if (comparison != 0) {
	return this;
	}
	if (lhs == rhs) {
	return this;
	}
	if (lhs == null) {
	comparison = -1;
	return this;
	}
	if (rhs == null) {
	comparison = 1;
	return this;
	}
	if (lhs.length != rhs.length) {
	comparison = lhs.length < rhs.length ? -1 : 1;
	return this;
	}
	for (int i = 0; i < lhs.length && comparison == 0; i++) {
	append(lhs[i], rhs[i], comparator);
	}
	return this;
	}

	/**
	* <p>Appends to the {@code builder} the deep comparison of
	* two {@code long} arrays.</p>
	*
	* <ol>
	* <li>Check if arrays are the same using {@code ==}</li>
	* <li>Check if for {@code null}, {@code null} is less than non-{@code null}</li>
	* <li>Check array length, a shorter length array is less than a longer length array</li>
	* <li>Check array contents element by element using {@link #append(long, long)}</li>
	* </ol>
	*
	* @param lhs left-hand array
	* @param rhs right-hand array
	* @return this - used to chain append calls
	*/
	public CompareToBuilder append(final long[] lhs, final long[] rhs) {
	if (comparison != 0) {
	return this;
	}
	if (lhs == rhs) {
	return this;
	}
	if (lhs == null) {
	comparison = -1;
	return this;
	}
	if (rhs == null) {
	comparison = 1;
	return this;
	}
	if (lhs.length != rhs.length) {
	comparison = lhs.length < rhs.length ? -1 : 1;
	return this;
	}
	for (int i = 0; i < lhs.length && comparison == 0; i++) {
	append(lhs[i], rhs[i]);
	}
	return this;
	}

	/**
	* <p>Appends to the {@code builder} the deep comparison of
	* two {@code int} arrays.</p>
	*
	* <ol>
	* <li>Check if arrays are the same using {@code ==}</li>
	* <li>Check if for {@code null}, {@code null} is less than non-{@code null}</li>
	* <li>Check array length, a shorter length array is less than a longer length array</li>
	* <li>Check array contents element by element using {@link #append(int, int)}</li>
	* </ol>
	*
	* @param lhs left-hand array
	* @param rhs right-hand array
	* @return this - used to chain append calls
	*/
	public CompareToBuilder append(final int[] lhs, final int[] rhs) {
	if (comparison != 0) {
	return this;
	}
	if (lhs == rhs) {
	return this;
	}
	if (lhs == null) {
	comparison = -1;
	return this;
	}
	if (rhs == null) {
	comparison = 1;
	return this;
	}
	if (lhs.length != rhs.length) {
	comparison = lhs.length < rhs.length ? -1 : 1;
	return this;
	}
	for (int i = 0; i < lhs.length && comparison == 0; i++) {
	append(lhs[i], rhs[i]);
	}
	return this;
	}

	/**
	* <p>Appends to the {@code builder} the deep comparison of
	* two {@code short} arrays.</p>
	*
	* <ol>
	* <li>Check if arrays are the same using {@code ==}</li>
	* <li>Check if for {@code null}, {@code null} is less than non-{@code null}</li>
	* <li>Check array length, a shorter length array is less than a longer length array</li>
	* <li>Check array contents element by element using {@link #append(short, short)}</li>
	* </ol>
	*
	* @param lhs left-hand array
	* @param rhs right-hand array
	* @return this - used to chain append calls
	*/
	public CompareToBuilder append(final short[] lhs, final short[] rhs) {
	if (comparison != 0) {
	return this;
	}
	if (lhs == rhs) {
	return this;
	}
	if (lhs == null) {
	comparison = -1;
	return this;
	}
	if (rhs == null) {
	comparison = 1;
	return this;
	}
	if (lhs.length != rhs.length) {
	comparison = lhs.length < rhs.length ? -1 : 1;
	return this;
	}
	for (int i = 0; i < lhs.length && comparison == 0; i++) {
	append(lhs[i], rhs[i]);
	}
	return this;
	}

	/**
	* <p>Appends to the {@code builder} the deep comparison of
	* two {@code char} arrays.</p>
	*
	* <ol>
	* <li>Check if arrays are the same using {@code ==}</li>
	* <li>Check if for {@code null}, {@code null} is less than non-{@code null}</li>
	* <li>Check array length, a shorter length array is less than a longer length array</li>
	* <li>Check array contents element by element using {@link #append(char, char)}</li>
	* </ol>
	*
	* @param lhs left-hand array
	* @param rhs right-hand array
	* @return this - used to chain append calls
	*/
	public CompareToBuilder append(final char[] lhs, final char[] rhs) {
	if (comparison != 0) {
	return this;
	}
	if (lhs == rhs) {
	return this;
	}
	if (lhs == null) {
	comparison = -1;
	return this;
	}
	if (rhs == null) {
	comparison = 1;
	return this;
	}
	if (lhs.length != rhs.length) {
	comparison = lhs.length < rhs.length ? -1 : 1;
	return this;
	}
	for (int i = 0; i < lhs.length && comparison == 0; i++) {
	append(lhs[i], rhs[i]);
	}
	return this;
	}

	/**
	* <p>Appends to the {@code builder} the deep comparison of
	* two {@code byte} arrays.</p>
	*
	* <ol>
	* <li>Check if arrays are the same using {@code ==}</li>
	* <li>Check if for {@code null}, {@code null} is less than non-{@code null}</li>
	* <li>Check array length, a shorter length array is less than a longer length array</li>
	* <li>Check array contents element by element using {@link #append(byte, byte)}</li>
	* </ol>
	*
	* @param lhs left-hand array
	* @param rhs right-hand array
	* @return this - used to chain append calls
	*/
	public CompareToBuilder append(final byte[] lhs, final byte[] rhs) {
	if (comparison != 0) {
	return this;
	}
	if (lhs == rhs) {
	return this;
	}
	if (lhs == null) {
	comparison = -1;
	return this;
	}
	if (rhs == null) {
	comparison = 1;
	return this;
	}
	if (lhs.length != rhs.length) {
	comparison = lhs.length < rhs.length ? -1 : 1;
	return this;
	}
	for (int i = 0; i < lhs.length && comparison == 0; i++) {
	append(lhs[i], rhs[i]);
	}
	return this;
	}

	/**
	* <p>Appends to the {@code builder} the deep comparison of
	* two {@code double} arrays.</p>
	*
	* <ol>
	* <li>Check if arrays are the same using {@code ==}</li>
	* <li>Check if for {@code null}, {@code null} is less than non-{@code null}</li>
	* <li>Check array length, a shorter length array is less than a longer length array</li>
	* <li>Check array contents element by element using {@link #append(double, double)}</li>
	* </ol>
	*
	* @param lhs left-hand array
	* @param rhs right-hand array
	* @return this - used to chain append calls
	*/
	public CompareToBuilder append(final double[] lhs, final double[] rhs) {
	if (comparison != 0) {
	return this;
	}
	if (lhs == rhs) {
	return this;
	}
	if (lhs == null) {
	comparison = -1;
	return this;
	}
	if (rhs == null) {
	comparison = 1;
	return this;
	}
	if (lhs.length != rhs.length) {
	comparison = lhs.length < rhs.length ? -1 : 1;
	return this;
	}
	for (int i = 0; i < lhs.length && comparison == 0; i++) {
	append(lhs[i], rhs[i]);
	}
	return this;
	}

	/**
	* <p>Appends to the {@code builder} the deep comparison of
	* two {@code float} arrays.</p>
	*
	* <ol>
	* <li>Check if arrays are the same using {@code ==}</li>
	* <li>Check if for {@code null}, {@code null} is less than non-{@code null}</li>
	* <li>Check array length, a shorter length array is less than a longer length array</li>
	* <li>Check array contents element by element using {@link #append(float, float)}</li>
	* </ol>
	*
	* @param lhs left-hand array
	* @param rhs right-hand array
	* @return this - used to chain append calls
	*/
	public CompareToBuilder append(final float[] lhs, final float[] rhs) {
	if (comparison != 0) {
	return this;
	}
	if (lhs == rhs) {
	return this;
	}
	if (lhs == null) {
	comparison = -1;
	return this;
	}
	if (rhs == null) {
	comparison = 1;
	return this;
	}
	if (lhs.length != rhs.length) {
	comparison = lhs.length < rhs.length ? -1 : 1;
	return this;
	}
	for (int i = 0; i < lhs.length && comparison == 0; i++) {
	append(lhs[i], rhs[i]);
	}
	return this;
	}

	/**
	* <p>Appends to the {@code builder} the deep comparison of
	* two {@code boolean} arrays.</p>
	*
	* <ol>
	* <li>Check if arrays are the same using {@code ==}</li>
	* <li>Check if for {@code null}, {@code null} is less than non-{@code null}</li>
	* <li>Check array length, a shorter length array is less than a longer length array</li>
	* <li>Check array contents element by element using {@link #append(boolean, boolean)}</li>
	* </ol>
	*
	* @param lhs left-hand array
	* @param rhs right-hand array
	* @return this - used to chain append calls
	*/
	public CompareToBuilder append(final boolean[] lhs, final boolean[] rhs) {
	if (comparison != 0) {
	return this;
	}
	if (lhs == rhs) {
	return this;
	}
	if (lhs == null) {
	comparison = -1;
	return this;
	}
	if (rhs == null) {
	comparison = 1;
	return this;
	}
	if (lhs.length != rhs.length) {
	comparison = lhs.length < rhs.length ? -1 : 1;
	return this;
	}
	for (int i = 0; i < lhs.length && comparison == 0; i++) {
	append(lhs[i], rhs[i]);
	}
	return this;
	}

	//-----------------------------------------------------------------------
	/**
	* Returns a negative integer, a positive integer, or zero as
	* the {@code builder} has judged the "left-hand" side
	* as less than, greater than, or equal to the "right-hand"
	* side.
	*
	* @return final comparison result
	* @see #build()
	*/
	public int toComparison() {
	return comparison;
	}

	/**
	* Returns a negative Integer, a positive Integer, or zero as
	* the {@code builder} has judged the "left-hand" side
	* as less than, greater than, or equal to the "right-hand"
	* side.
	*
	* @return final comparison result as an Integer
	* @see #toComparison()
	* @since 3.0
	*/
	@Override
	public Integer build() {
	return Integer.valueOf(toComparison());
	}
	}

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