/**
* Copyright (C) 2009 - present by OpenGamma Inc. and the OpenGamma group of companies
*
* Please see distribution for license.
*/
package com.opengamma.strata.collect.tuple;
import java.io.Serializable;
import java.util.Map;
import java.util.NoSuchElementException;
import java.util.Set;
import org.joda.beans.Bean;
import org.joda.beans.BeanBuilder;
import org.joda.beans.BeanDefinition;
import org.joda.beans.ImmutableBean;
import org.joda.beans.JodaBeanUtils;
import org.joda.beans.MetaProperty;
import org.joda.beans.Property;
import org.joda.beans.PropertyDefinition;
import org.joda.beans.impl.direct.DirectFieldsBeanBuilder;
import org.joda.beans.impl.direct.DirectMetaBean;
import org.joda.beans.impl.direct.DirectMetaProperty;
import org.joda.beans.impl.direct.DirectMetaPropertyMap;
import com.google.common.collect.ComparisonChain;
import com.google.common.collect.ImmutableList;
/**
* An immutable pair consisting of two elements.
* <p>
* This implementation refers to the elements as 'first' and 'second'.
* The elements cannot be null.
* <p>
* Although the implementation is immutable, there is no restriction on the objects
* that may be stored. If mutable objects are stored in the pair, then the pair itself
* effectively becomes mutable.
* <p>
* Some primitive specializations of this class are provided, such as {@link DoublesPair}.
* <p>
* This class is immutable and thread-safe if the stored objects are immutable.
*
* @param <A> the first element type
* @param <B> the second element type
*/
@BeanDefinition(builderScope = "private")
public final class Pair<A, B>
implements ImmutableBean, Tuple, Comparable<Pair<A, B>>, Serializable {
/**
* The first element in this pair.
*/
@PropertyDefinition(validate = "notNull")
private final A first;
/**
* The second element in this pair.
*/
@PropertyDefinition(validate = "notNull")
private final B second;
//-------------------------------------------------------------------------
/**
* Obtains a pair inferring the types.
*
* @param <A> the first element type
* @param <B> the second element type
* @param first the first element
* @param second the second element
* @return a pair formed from the two parameters
*/
public static <A, B> Pair<A, B> of(A first, B second) {
return new Pair<>(first, second);
}
//-------------------------------------------------------------------------
/**
* Gets the number of elements held by this pair.
*
* @return size 2
*/
@Override
public int size() {
return 2;
}
/**
* Gets the elements from this pair as a list.
* <p>
* The list returns each element in the pair in order.
*
* @return the elements as an immutable list
*/
@Override
public ImmutableList<Object> elements() {
return ImmutableList.of(first, second);
}
//-------------------------------------------------------------------------
/**
* Compares the pair based on the first element followed by the second element.
* <p>
* The element types must be {@code Comparable}.
*
* @param other the other pair
* @return negative if this is less, zero if equal, positive if greater
* @throws ClassCastException if either object is not comparable
*/
@Override
public int compareTo(Pair<A, B> other) {
return ComparisonChain.start()
.compare((Comparable<?>) first, (Comparable<?>) other.first)
.compare((Comparable<?>) second, (Comparable<?>) other.second)
.result();
}
/**
* Gets the pair using a standard string format.
* <p>
* The standard format is '[$first, $second]'. Spaces around the values are trimmed.
*
* @return the pair as a string
*/
@Override
public String toString() {
return new StringBuilder()
.append('[')
.append(first)
.append(", ")
.append(second)
.append(']')
.toString();
}
//------------------------- AUTOGENERATED START -------------------------
///CLOVER:OFF
/**
* The meta-bean for {@code Pair}.
* @return the meta-bean, not null
*/
@SuppressWarnings("rawtypes")
public static Pair.Meta meta() {
return Pair.Meta.INSTANCE;
}
/**
* The meta-bean for {@code Pair}.
* @param <R> the first generic type
* @param <S> the second generic type
* @param cls1 the first generic type
* @param cls2 the second generic type
* @return the meta-bean, not null
*/
@SuppressWarnings("unchecked")
public static <R, S> Pair.Meta<R, S> metaPair(Class<R> cls1, Class<S> cls2) {
return Pair.Meta.INSTANCE;
}
static {
JodaBeanUtils.registerMetaBean(Pair.Meta.INSTANCE);
}
/**
* The serialization version id.
*/
private static final long serialVersionUID = 1L;
private Pair(
A first,
B second) {
JodaBeanUtils.notNull(first, "first");
JodaBeanUtils.notNull(second, "second");
this.first = first;
this.second = second;
}
@SuppressWarnings("unchecked")
@Override
public Pair.Meta<A, B> metaBean() {
return Pair.Meta.INSTANCE;
}
@Override
public <R> Property<R> property(String propertyName) {
return metaBean().<R>metaProperty(propertyName).createProperty(this);
}
@Override
public Set<String> propertyNames() {
return metaBean().metaPropertyMap().keySet();
}
//-----------------------------------------------------------------------
/**
* Gets the first element in this pair.
* @return the value of the property, not null
*/
public A getFirst() {
return first;
}
//-----------------------------------------------------------------------
/**
* Gets the second element in this pair.
* @return the value of the property, not null
*/
public B getSecond() {
return second;
}
//-----------------------------------------------------------------------
@Override
public boolean equals(Object obj) {
if (obj == this) {
return true;
}
if (obj != null && obj.getClass() == this.getClass()) {
Pair<?, ?> other = (Pair<?, ?>) obj;
return JodaBeanUtils.equal(first, other.first) &&
JodaBeanUtils.equal(second, other.second);
}
return false;
}
@Override
public int hashCode() {
int hash = getClass().hashCode();
hash = hash * 31 + JodaBeanUtils.hashCode(first);
hash = hash * 31 + JodaBeanUtils.hashCode(second);
return hash;
}
//-----------------------------------------------------------------------
/**
* The meta-bean for {@code Pair}.
* @param <A> the type
* @param <B> the type
*/
public static final class Meta<A, B> extends DirectMetaBean {
/**
* The singleton instance of the meta-bean.
*/
@SuppressWarnings("rawtypes")
static final Meta INSTANCE = new Meta();
/**
* The meta-property for the {@code first} property.
*/
@SuppressWarnings({"unchecked", "rawtypes" })
private final MetaProperty<A> first = (DirectMetaProperty) DirectMetaProperty.ofImmutable(
this, "first", Pair.class, Object.class);
/**
* The meta-property for the {@code second} property.
*/
@SuppressWarnings({"unchecked", "rawtypes" })
private final MetaProperty<B> second = (DirectMetaProperty) DirectMetaProperty.ofImmutable(
this, "second", Pair.class, Object.class);
/**
* The meta-properties.
*/
private final Map<String, MetaProperty<?>> metaPropertyMap$ = new DirectMetaPropertyMap(
this, null,
"first",
"second");
/**
* Restricted constructor.
*/
private Meta() {
}
@Override
protected MetaProperty<?> metaPropertyGet(String propertyName) {
switch (propertyName.hashCode()) {
case 97440432: // first
return first;
case -906279820: // second
return second;
}
return super.metaPropertyGet(propertyName);
}
@Override
public BeanBuilder<? extends Pair<A, B>> builder() {
return new Pair.Builder<A, B>();
}
@SuppressWarnings({"unchecked", "rawtypes" })
@Override
public Class<? extends Pair<A, B>> beanType() {
return (Class) Pair.class;
}
@Override
public Map<String, MetaProperty<?>> metaPropertyMap() {
return metaPropertyMap$;
}
//-----------------------------------------------------------------------
/**
* The meta-property for the {@code first} property.
* @return the meta-property, not null
*/
public MetaProperty<A> first() {
return first;
}
/**
* The meta-property for the {@code second} property.
* @return the meta-property, not null
*/
public MetaProperty<B> second() {
return second;
}
//-----------------------------------------------------------------------
@Override
protected Object propertyGet(Bean bean, String propertyName, boolean quiet) {
switch (propertyName.hashCode()) {
case 97440432: // first
return ((Pair<?, ?>) bean).getFirst();
case -906279820: // second
return ((Pair<?, ?>) bean).getSecond();
}
return super.propertyGet(bean, propertyName, quiet);
}
@Override
protected void propertySet(Bean bean, String propertyName, Object newValue, boolean quiet) {
metaProperty(propertyName);
if (quiet) {
return;
}
throw new UnsupportedOperationException("Property cannot be written: " + propertyName);
}
}
//-----------------------------------------------------------------------
/**
* The bean-builder for {@code Pair}.
* @param <A> the type
* @param <B> the type
*/
private static final class Builder<A, B> extends DirectFieldsBeanBuilder<Pair<A, B>> {
private A first;
private B second;
/**
* Restricted constructor.
*/
private Builder() {
}
//-----------------------------------------------------------------------
@Override
public Object get(String propertyName) {
switch (propertyName.hashCode()) {
case 97440432: // first
return first;
case -906279820: // second
return second;
default:
throw new NoSuchElementException("Unknown property: " + propertyName);
}
}
@SuppressWarnings("unchecked")
@Override
public Builder<A, B> set(String propertyName, Object newValue) {
switch (propertyName.hashCode()) {
case 97440432: // first
this.first = (A) newValue;
break;
case -906279820: // second
this.second = (B) newValue;
break;
default:
throw new NoSuchElementException("Unknown property: " + propertyName);
}
return this;
}
@Override
public Builder<A, B> set(MetaProperty<?> property, Object value) {
super.set(property, value);
return this;
}
@Override
public Builder<A, B> setString(String propertyName, String value) {
setString(meta().metaProperty(propertyName), value);
return this;
}
@Override
public Builder<A, B> setString(MetaProperty<?> property, String value) {
super.setString(property, value);
return this;
}
@Override
public Builder<A, B> setAll(Map<String, ? extends Object> propertyValueMap) {
super.setAll(propertyValueMap);
return this;
}
@Override
public Pair<A, B> build() {
return new Pair<A, B>(
first,
second);
}
//-----------------------------------------------------------------------
@Override
public String toString() {
StringBuilder buf = new StringBuilder(96);
buf.append("Pair.Builder{");
buf.append("first").append('=').append(JodaBeanUtils.toString(first)).append(',').append(' ');
buf.append("second").append('=').append(JodaBeanUtils.toString(second));
buf.append('}');
return buf.toString();
}
}
///CLOVER:ON
//-------------------------- AUTOGENERATED END --------------------------
}