guava/src/com/google/common/collect/GeneralRange.java - platform/external/guava - Git at Google

 /*
  * Copyright (C) 2011 The Guava Authors
  *
  * Licensed 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 com.google.common.collect;

 import static com.google.common.base.Preconditions.checkArgument;
 import static com.google.common.base.Preconditions.checkNotNull;
 import static com.google.common.collect.BoundType.CLOSED;
 import static com.google.common.collect.BoundType.OPEN;
 import static com.google.common.collect.NullnessCasts.uncheckedCastNullableTToT;

 import com.google.common.annotations.GwtCompatible;
 import com.google.common.base.Objects;
 import java.io.Serializable;
 import java.util.Comparator;
 import javax.annotation.CheckForNull;
 import org.checkerframework.checker.nullness.qual.Nullable;

 /**
  * A generalized interval on any ordering, for internal use. Supports {@code null}. Unlike {@link
  * Range}, this allows the use of an arbitrary comparator. This is designed for use in the
  * implementation of subcollections of sorted collection types.
  *
  * <p>Whenever possible, use {@code Range} instead, which is better supported.
  *
  * @author Louis Wasserman
  */
 @GwtCompatible(serializable = true)
 @ElementTypesAreNonnullByDefault
 final class GeneralRange<T extends @Nullable Object> implements Serializable {
   /** Converts a Range to a GeneralRange. */
   static <T extends Comparable> GeneralRange<T> from(Range<T> range) {
     T lowerEndpoint = range.hasLowerBound() ? range.lowerEndpoint() : null;
     BoundType lowerBoundType = range.hasLowerBound() ? range.lowerBoundType() : OPEN;

     T upperEndpoint = range.hasUpperBound() ? range.upperEndpoint() : null;
     BoundType upperBoundType = range.hasUpperBound() ? range.upperBoundType() : OPEN;
     return new GeneralRange<>(
         Ordering.natural(),
         range.hasLowerBound(),
         lowerEndpoint,
         lowerBoundType,
         range.hasUpperBound(),
         upperEndpoint,
         upperBoundType);
   }

   /** Returns the whole range relative to the specified comparator. */
   static <T extends @Nullable Object> GeneralRange<T> all(Comparator<? super T> comparator) {
     return new GeneralRange<>(comparator, false, null, OPEN, false, null, OPEN);
   }

   /**
    * Returns everything above the endpoint relative to the specified comparator, with the specified
    * endpoint behavior.
    */
   static <T extends @Nullable Object> GeneralRange<T> downTo(
       Comparator<? super T> comparator, @ParametricNullness T endpoint, BoundType boundType) {
     return new GeneralRange<>(comparator, true, endpoint, boundType, false, null, OPEN);
   }

   /**
    * Returns everything below the endpoint relative to the specified comparator, with the specified
    * endpoint behavior.
    */
   static <T extends @Nullable Object> GeneralRange<T> upTo(
       Comparator<? super T> comparator, @ParametricNullness T endpoint, BoundType boundType) {
     return new GeneralRange<>(comparator, false, null, OPEN, true, endpoint, boundType);
   }

   /**
    * Returns everything between the endpoints relative to the specified comparator, with the
    * specified endpoint behavior.
    */
   static <T extends @Nullable Object> GeneralRange<T> range(
       Comparator<? super T> comparator,
       @ParametricNullness T lower,
       BoundType lowerType,
       @ParametricNullness T upper,
       BoundType upperType) {
     return new GeneralRange<>(comparator, true, lower, lowerType, true, upper, upperType);
   }

   private final Comparator<? super T> comparator;
   private final boolean hasLowerBound;
   @CheckForNull private final T lowerEndpoint;
   private final BoundType lowerBoundType;
   private final boolean hasUpperBound;
   @CheckForNull private final T upperEndpoint;
   private final BoundType upperBoundType;

   private GeneralRange(
       Comparator<? super T> comparator,
       boolean hasLowerBound,
       @CheckForNull T lowerEndpoint,
       BoundType lowerBoundType,
       boolean hasUpperBound,
       @CheckForNull T upperEndpoint,
       BoundType upperBoundType) {
     this.comparator = checkNotNull(comparator);
     this.hasLowerBound = hasLowerBound;
     this.hasUpperBound = hasUpperBound;
     this.lowerEndpoint = lowerEndpoint;
     this.lowerBoundType = checkNotNull(lowerBoundType);
     this.upperEndpoint = upperEndpoint;
     this.upperBoundType = checkNotNull(upperBoundType);

     // Trigger any exception that the comparator would throw for the endpoints.
     /*
      * uncheckedCastNullableTToT is safe as long as the callers are careful to pass a "real" T
      * whenever they pass `true` for the matching `has*Bound` parameter.
      */
     if (hasLowerBound) {
       comparator.compare(
           uncheckedCastNullableTToT(lowerEndpoint), uncheckedCastNullableTToT(lowerEndpoint));
     }
     if (hasUpperBound) {
       comparator.compare(
           uncheckedCastNullableTToT(upperEndpoint), uncheckedCastNullableTToT(upperEndpoint));
     }

     if (hasLowerBound && hasUpperBound) {
       int cmp =
           comparator.compare(
               uncheckedCastNullableTToT(lowerEndpoint), uncheckedCastNullableTToT(upperEndpoint));
       // be consistent with Range
       checkArgument(
           cmp <= 0, "lowerEndpoint (%s) > upperEndpoint (%s)", lowerEndpoint, upperEndpoint);
       if (cmp == 0) {
         checkArgument(lowerBoundType != OPEN || upperBoundType != OPEN);
       }
     }
   }

   Comparator<? super T> comparator() {
     return comparator;
   }

   boolean hasLowerBound() {
     return hasLowerBound;
   }

   boolean hasUpperBound() {
     return hasUpperBound;
   }

   boolean isEmpty() {
     // The casts are safe because of the has*Bound() checks.
     return (hasUpperBound() && tooLow(uncheckedCastNullableTToT(getUpperEndpoint())))
         || (hasLowerBound() && tooHigh(uncheckedCastNullableTToT(getLowerEndpoint())));
   }

   boolean tooLow(@ParametricNullness T t) {
     if (!hasLowerBound()) {
       return false;
     }
     // The cast is safe because of the hasLowerBound() check.
     T lbound = uncheckedCastNullableTToT(getLowerEndpoint());
     int cmp = comparator.compare(t, lbound);
     return cmp < 0 | (cmp == 0 & getLowerBoundType() == OPEN);
   }

   boolean tooHigh(@ParametricNullness T t) {
     if (!hasUpperBound()) {
       return false;
     }
     // The cast is safe because of the hasUpperBound() check.
     T ubound = uncheckedCastNullableTToT(getUpperEndpoint());
     int cmp = comparator.compare(t, ubound);
     return cmp > 0 | (cmp == 0 & getUpperBoundType() == OPEN);
   }

   boolean contains(@ParametricNullness T t) {
     return !tooLow(t) && !tooHigh(t);
   }

   /**
    * Returns the intersection of the two ranges, or an empty range if their intersection is empty.
    */
   @SuppressWarnings("nullness") // TODO(cpovirk): Add casts as needed. Will be noisy and annoying...
   GeneralRange<T> intersect(GeneralRange<T> other) {
     checkNotNull(other);
     checkArgument(comparator.equals(other.comparator));

     boolean hasLowBound = this.hasLowerBound;
     T lowEnd = getLowerEndpoint();
     BoundType lowType = getLowerBoundType();
     if (!hasLowerBound()) {
       hasLowBound = other.hasLowerBound;
       lowEnd = other.getLowerEndpoint();
       lowType = other.getLowerBoundType();
     } else if (other.hasLowerBound()) {
       int cmp = comparator.compare(getLowerEndpoint(), other.getLowerEndpoint());
       if (cmp < 0 || (cmp == 0 && other.getLowerBoundType() == OPEN)) {
         lowEnd = other.getLowerEndpoint();
         lowType = other.getLowerBoundType();
       }
     }

     boolean hasUpBound = this.hasUpperBound;
     T upEnd = getUpperEndpoint();
     BoundType upType = getUpperBoundType();
     if (!hasUpperBound()) {
       hasUpBound = other.hasUpperBound;
       upEnd = other.getUpperEndpoint();
       upType = other.getUpperBoundType();
     } else if (other.hasUpperBound()) {
       int cmp = comparator.compare(getUpperEndpoint(), other.getUpperEndpoint());
       if (cmp > 0 || (cmp == 0 && other.getUpperBoundType() == OPEN)) {
         upEnd = other.getUpperEndpoint();
         upType = other.getUpperBoundType();
       }
     }

     if (hasLowBound && hasUpBound) {
       int cmp = comparator.compare(lowEnd, upEnd);
       if (cmp > 0 || (cmp == 0 && lowType == OPEN && upType == OPEN)) {
         // force allowed empty range
         lowEnd = upEnd;
         lowType = OPEN;
         upType = CLOSED;
       }
     }

     return new GeneralRange<>(comparator, hasLowBound, lowEnd, lowType, hasUpBound, upEnd, upType);
   }

   @Override
   public boolean equals(@CheckForNull Object obj) {
     if (obj instanceof GeneralRange) {
       GeneralRange<?> r = (GeneralRange<?>) obj;
       return comparator.equals(r.comparator)
           && hasLowerBound == r.hasLowerBound
           && hasUpperBound == r.hasUpperBound
           && getLowerBoundType().equals(r.getLowerBoundType())
           && getUpperBoundType().equals(r.getUpperBoundType())
           && Objects.equal(getLowerEndpoint(), r.getLowerEndpoint())
           && Objects.equal(getUpperEndpoint(), r.getUpperEndpoint());
     }
     return false;
   }

   @Override
   public int hashCode() {
     return Objects.hashCode(
         comparator,
         getLowerEndpoint(),
         getLowerBoundType(),
         getUpperEndpoint(),
         getUpperBoundType());
   }

   @CheckForNull private transient GeneralRange<T> reverse;

   /** Returns the same range relative to the reversed comparator. */
   GeneralRange<T> reverse() {
     GeneralRange<T> result = reverse;
     if (result == null) {
       result =
           new GeneralRange<>(
               Ordering.from(comparator).reverse(),
               hasUpperBound,
               getUpperEndpoint(),
               getUpperBoundType(),
               hasLowerBound,
               getLowerEndpoint(),
               getLowerBoundType());
       result.reverse = this;
       return this.reverse = result;
     }
     return result;
   }

   @Override
   public String toString() {
     return comparator
         + ":"
         + (lowerBoundType == CLOSED ? '[' : '(')
         + (hasLowerBound ? lowerEndpoint : "-\u221e")
         + ','
         + (hasUpperBound ? upperEndpoint : "\u221e")
         + (upperBoundType == CLOSED ? ']' : ')');
   }

   @CheckForNull
   T getLowerEndpoint() {
     return lowerEndpoint;
   }

   BoundType getLowerBoundType() {
     return lowerBoundType;
   }

   @CheckForNull
   T getUpperEndpoint() {
     return upperEndpoint;
   }

   BoundType getUpperBoundType() {
     return upperBoundType;
   }
 }
	/*
	* Copyright (C) 2011 The Guava Authors
	*
	* Licensed 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 com.google.common.collect;

	import static com.google.common.base.Preconditions.checkArgument;
	import static com.google.common.base.Preconditions.checkNotNull;
	import static com.google.common.collect.BoundType.CLOSED;
	import static com.google.common.collect.BoundType.OPEN;
	import static com.google.common.collect.NullnessCasts.uncheckedCastNullableTToT;

	import com.google.common.annotations.GwtCompatible;
	import com.google.common.base.Objects;
	import java.io.Serializable;
	import java.util.Comparator;
	import javax.annotation.CheckForNull;
	import org.checkerframework.checker.nullness.qual.Nullable;

	/**
	* A generalized interval on any ordering, for internal use. Supports {@code null}. Unlike {@link
	* Range}, this allows the use of an arbitrary comparator. This is designed for use in the
	* implementation of subcollections of sorted collection types.
	*
	* <p>Whenever possible, use {@code Range} instead, which is better supported.
	*
	* @author Louis Wasserman
	*/
	@GwtCompatible(serializable = true)
	@ElementTypesAreNonnullByDefault
	final class GeneralRange<T extends @Nullable Object> implements Serializable {
	/** Converts a Range to a GeneralRange. */
	static <T extends Comparable> GeneralRange<T> from(Range<T> range) {
	T lowerEndpoint = range.hasLowerBound() ? range.lowerEndpoint() : null;
	BoundType lowerBoundType = range.hasLowerBound() ? range.lowerBoundType() : OPEN;

	T upperEndpoint = range.hasUpperBound() ? range.upperEndpoint() : null;
	BoundType upperBoundType = range.hasUpperBound() ? range.upperBoundType() : OPEN;
	return new GeneralRange<>(
	Ordering.natural(),
	range.hasLowerBound(),
	lowerEndpoint,
	lowerBoundType,
	range.hasUpperBound(),
	upperEndpoint,
	upperBoundType);
	}

	/** Returns the whole range relative to the specified comparator. */
	static <T extends @Nullable Object> GeneralRange<T> all(Comparator<? super T> comparator) {
	return new GeneralRange<>(comparator, false, null, OPEN, false, null, OPEN);
	}

	/**
	* Returns everything above the endpoint relative to the specified comparator, with the specified
	* endpoint behavior.
	*/
	static <T extends @Nullable Object> GeneralRange<T> downTo(
	Comparator<? super T> comparator, @ParametricNullness T endpoint, BoundType boundType) {
	return new GeneralRange<>(comparator, true, endpoint, boundType, false, null, OPEN);
	}

	/**
	* Returns everything below the endpoint relative to the specified comparator, with the specified
	* endpoint behavior.
	*/
	static <T extends @Nullable Object> GeneralRange<T> upTo(
	Comparator<? super T> comparator, @ParametricNullness T endpoint, BoundType boundType) {
	return new GeneralRange<>(comparator, false, null, OPEN, true, endpoint, boundType);
	}

	/**
	* Returns everything between the endpoints relative to the specified comparator, with the
	* specified endpoint behavior.
	*/
	static <T extends @Nullable Object> GeneralRange<T> range(
	Comparator<? super T> comparator,
	@ParametricNullness T lower,
	BoundType lowerType,
	@ParametricNullness T upper,
	BoundType upperType) {
	return new GeneralRange<>(comparator, true, lower, lowerType, true, upper, upperType);
	}

	private final Comparator<? super T> comparator;
	private final boolean hasLowerBound;
	@CheckForNull private final T lowerEndpoint;
	private final BoundType lowerBoundType;
	private final boolean hasUpperBound;
	@CheckForNull private final T upperEndpoint;
	private final BoundType upperBoundType;

	private GeneralRange(
	Comparator<? super T> comparator,
	boolean hasLowerBound,
	@CheckForNull T lowerEndpoint,
	BoundType lowerBoundType,
	boolean hasUpperBound,
	@CheckForNull T upperEndpoint,
	BoundType upperBoundType) {
	this.comparator = checkNotNull(comparator);
	this.hasLowerBound = hasLowerBound;
	this.hasUpperBound = hasUpperBound;
	this.lowerEndpoint = lowerEndpoint;
	this.lowerBoundType = checkNotNull(lowerBoundType);
	this.upperEndpoint = upperEndpoint;
	this.upperBoundType = checkNotNull(upperBoundType);

	// Trigger any exception that the comparator would throw for the endpoints.
	/*
	* uncheckedCastNullableTToT is safe as long as the callers are careful to pass a "real" T
	* whenever they pass `true` for the matching `has*Bound` parameter.
	*/
	if (hasLowerBound) {
	comparator.compare(
	uncheckedCastNullableTToT(lowerEndpoint), uncheckedCastNullableTToT(lowerEndpoint));
	}
	if (hasUpperBound) {
	comparator.compare(
	uncheckedCastNullableTToT(upperEndpoint), uncheckedCastNullableTToT(upperEndpoint));
	}

	if (hasLowerBound && hasUpperBound) {
	int cmp =
	comparator.compare(
	uncheckedCastNullableTToT(lowerEndpoint), uncheckedCastNullableTToT(upperEndpoint));
	// be consistent with Range
	checkArgument(
	cmp <= 0, "lowerEndpoint (%s) > upperEndpoint (%s)", lowerEndpoint, upperEndpoint);
	if (cmp == 0) {
	checkArgument(lowerBoundType != OPEN \|\| upperBoundType != OPEN);
	}
	}
	}

	Comparator<? super T> comparator() {
	return comparator;
	}

	boolean hasLowerBound() {
	return hasLowerBound;
	}

	boolean hasUpperBound() {
	return hasUpperBound;
	}

	boolean isEmpty() {
	// The casts are safe because of the has*Bound() checks.
	return (hasUpperBound() && tooLow(uncheckedCastNullableTToT(getUpperEndpoint())))
	\|\| (hasLowerBound() && tooHigh(uncheckedCastNullableTToT(getLowerEndpoint())));
	}

	boolean tooLow(@ParametricNullness T t) {
	if (!hasLowerBound()) {
	return false;
	}
	// The cast is safe because of the hasLowerBound() check.
	T lbound = uncheckedCastNullableTToT(getLowerEndpoint());
	int cmp = comparator.compare(t, lbound);
	return cmp < 0 \| (cmp == 0 & getLowerBoundType() == OPEN);
	}

	boolean tooHigh(@ParametricNullness T t) {
	if (!hasUpperBound()) {
	return false;
	}
	// The cast is safe because of the hasUpperBound() check.
	T ubound = uncheckedCastNullableTToT(getUpperEndpoint());
	int cmp = comparator.compare(t, ubound);
	return cmp > 0 \| (cmp == 0 & getUpperBoundType() == OPEN);
	}

	boolean contains(@ParametricNullness T t) {
	return !tooLow(t) && !tooHigh(t);
	}

	/**
	* Returns the intersection of the two ranges, or an empty range if their intersection is empty.
	*/
	@SuppressWarnings("nullness") // TODO(cpovirk): Add casts as needed. Will be noisy and annoying...
	GeneralRange<T> intersect(GeneralRange<T> other) {
	checkNotNull(other);
	checkArgument(comparator.equals(other.comparator));

	boolean hasLowBound = this.hasLowerBound;
	T lowEnd = getLowerEndpoint();
	BoundType lowType = getLowerBoundType();
	if (!hasLowerBound()) {
	hasLowBound = other.hasLowerBound;
	lowEnd = other.getLowerEndpoint();
	lowType = other.getLowerBoundType();
	} else if (other.hasLowerBound()) {
	int cmp = comparator.compare(getLowerEndpoint(), other.getLowerEndpoint());
	if (cmp < 0 \|\| (cmp == 0 && other.getLowerBoundType() == OPEN)) {
	lowEnd = other.getLowerEndpoint();
	lowType = other.getLowerBoundType();
	}
	}

	boolean hasUpBound = this.hasUpperBound;
	T upEnd = getUpperEndpoint();
	BoundType upType = getUpperBoundType();
	if (!hasUpperBound()) {
	hasUpBound = other.hasUpperBound;
	upEnd = other.getUpperEndpoint();
	upType = other.getUpperBoundType();
	} else if (other.hasUpperBound()) {
	int cmp = comparator.compare(getUpperEndpoint(), other.getUpperEndpoint());
	if (cmp > 0 \|\| (cmp == 0 && other.getUpperBoundType() == OPEN)) {
	upEnd = other.getUpperEndpoint();
	upType = other.getUpperBoundType();
	}
	}

	if (hasLowBound && hasUpBound) {
	int cmp = comparator.compare(lowEnd, upEnd);
	if (cmp > 0 \|\| (cmp == 0 && lowType == OPEN && upType == OPEN)) {
	// force allowed empty range
	lowEnd = upEnd;
	lowType = OPEN;
	upType = CLOSED;
	}
	}

	return new GeneralRange<>(comparator, hasLowBound, lowEnd, lowType, hasUpBound, upEnd, upType);
	}

	@Override
	public boolean equals(@CheckForNull Object obj) {
	if (obj instanceof GeneralRange) {
	GeneralRange<?> r = (GeneralRange<?>) obj;
	return comparator.equals(r.comparator)
	&& hasLowerBound == r.hasLowerBound
	&& hasUpperBound == r.hasUpperBound
	&& getLowerBoundType().equals(r.getLowerBoundType())
	&& getUpperBoundType().equals(r.getUpperBoundType())
	&& Objects.equal(getLowerEndpoint(), r.getLowerEndpoint())
	&& Objects.equal(getUpperEndpoint(), r.getUpperEndpoint());
	}
	return false;
	}

	@Override
	public int hashCode() {
	return Objects.hashCode(
	comparator,
	getLowerEndpoint(),
	getLowerBoundType(),
	getUpperEndpoint(),
	getUpperBoundType());
	}

	@CheckForNull private transient GeneralRange<T> reverse;

	/** Returns the same range relative to the reversed comparator. */
	GeneralRange<T> reverse() {
	GeneralRange<T> result = reverse;
	if (result == null) {
	result =
	new GeneralRange<>(
	Ordering.from(comparator).reverse(),
	hasUpperBound,
	getUpperEndpoint(),
	getUpperBoundType(),
	hasLowerBound,
	getLowerEndpoint(),
	getLowerBoundType());
	result.reverse = this;
	return this.reverse = result;
	}
	return result;
	}

	@Override
	public String toString() {
	return comparator
	+ ":"
	+ (lowerBoundType == CLOSED ? '[' : '(')
	+ (hasLowerBound ? lowerEndpoint : "-\u221e")
	+ ','
	+ (hasUpperBound ? upperEndpoint : "\u221e")
	+ (upperBoundType == CLOSED ? ']' : ')');
	}

	@CheckForNull
	T getLowerEndpoint() {
	return lowerEndpoint;
	}

	BoundType getLowerBoundType() {
	return lowerBoundType;
	}

	@CheckForNull
	T getUpperEndpoint() {
	return upperEndpoint;
	}

	BoundType getUpperBoundType() {
	return upperBoundType;
	}
	}