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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.cassandra.dht;
import java.io.DataInput;
import java.io.IOException;
import java.io.Serializable;
import java.util.Collection;
import java.util.List;
import org.apache.cassandra.db.DecoratedKey;
import org.apache.cassandra.db.PartitionPosition;
import org.apache.cassandra.db.TypeSizes;
import org.apache.cassandra.db.marshal.AbstractType;
import org.apache.cassandra.io.util.DataOutputPlus;
import org.apache.cassandra.net.MessagingService;
import org.apache.cassandra.utils.Pair;
public abstract class AbstractBounds> implements Serializable
{
private static final long serialVersionUID = 1L;
public static final IPartitionerDependentSerializer> tokenSerializer =
new AbstractBoundsSerializer(Token.serializer);
public static final IPartitionerDependentSerializer> rowPositionSerializer =
new AbstractBoundsSerializer(PartitionPosition.serializer);
private enum Type
{
RANGE,
BOUNDS
}
public final T left;
public final T right;
public AbstractBounds(T left, T right)
{
assert left.getPartitioner() == right.getPartitioner();
this.left = left;
this.right = right;
}
/**
* Given token T and AbstractBounds ?L,R?, returns Pair(?L,T], (T,R?),
* where ? means that the same type of AbstractBounds is returned as the original.
*
* Put another way, returns a Pair of everything this AbstractBounds contains
* up to and including the split position, and everything it contains after
* (not including the split position).
*
* The original AbstractBounds must either contain the position T, or T
* should be equals to the left bound L.
*
* If the split would only yield the same AbstractBound, null is returned
* instead.
*/
public abstract Pair, AbstractBounds> split(T position);
public abstract boolean inclusiveLeft();
public abstract boolean inclusiveRight();
/**
* Whether {@code left} and {@code right} forms a wrapping interval, that is if unwrapping wouldn't be a no-op.
*
* Note that the semantic is slightly different from {@link Range#isWrapAround()} in the sense that if both
* {@code right} are minimal (for the partitioner), this methods return false (doesn't wrap) while
* {@link Range#isWrapAround()} returns true (does wrap). This is confusing and we should fix it by
* refactoring/rewriting the whole AbstractBounds hierarchy with cleaner semantics, but we don't want to risk
* breaking something by changing {@link Range#isWrapAround()} in the meantime.
*/
public static > boolean strictlyWrapsAround(T left, T right)
{
return !(left.compareTo(right) <= 0 || right.isMinimum());
}
public static > boolean noneStrictlyWrapsAround(Collection> bounds)
{
for (AbstractBounds b : bounds)
{
if (strictlyWrapsAround(b.left, b.right))
return false;
}
return true;
}
@Override
public int hashCode()
{
return 31 * left.hashCode() + right.hashCode();
}
/** return true if @param range intersects any of the given @param ranges */
public boolean intersects(Iterable> ranges)
{
for (Range range2 : ranges)
{
if (range2.intersects(this))
return true;
}
return false;
}
public abstract boolean contains(T start);
public abstract List> unwrap();
public String getString(AbstractType keyValidator)
{
return getOpeningString() + format(left, keyValidator) + ", " + format(right, keyValidator) + getClosingString();
}
private String format(T value, AbstractType keyValidator)
{
if (value instanceof DecoratedKey)
{
return keyValidator.getString(((DecoratedKey)value).getKey());
}
else
{
return value.toString();
}
}
protected abstract String getOpeningString();
protected abstract String getClosingString();
public abstract boolean isStartInclusive();
public abstract boolean isEndInclusive();
public abstract AbstractBounds withNewRight(T newRight);
public static class AbstractBoundsSerializer> implements IPartitionerDependentSerializer>
{
private static final int IS_TOKEN_FLAG = 0x01;
private static final int START_INCLUSIVE_FLAG = 0x02;
private static final int END_INCLUSIVE_FLAG = 0x04;
IPartitionerDependentSerializer serializer;
// Use for pre-3.0 protocol
private static int kindInt(AbstractBounds ab)
{
int kind = ab instanceof Range ? Type.RANGE.ordinal() : Type.BOUNDS.ordinal();
if (!(ab.left instanceof Token))
kind = -(kind + 1);
return kind;
}
// For from 3.0 onwards
private static int kindFlags(AbstractBounds ab)
{
int flags = 0;
if (ab.left instanceof Token)
flags |= IS_TOKEN_FLAG;
if (ab.isStartInclusive())
flags |= START_INCLUSIVE_FLAG;
if (ab.isEndInclusive())
flags |= END_INCLUSIVE_FLAG;
return flags;
}
public AbstractBoundsSerializer(IPartitionerDependentSerializer serializer)
{
this.serializer = serializer;
}
public void serialize(AbstractBounds range, DataOutputPlus out, int version) throws IOException
{
/*
* The first int tells us if it's a range or bounds (depending on the value) _and_ if it's tokens or keys (depending on the
* sign). We use negative kind for keys so as to preserve the serialization of token from older version.
*/
if (version < MessagingService.VERSION_30)
out.writeInt(kindInt(range));
else
out.writeByte(kindFlags(range));
serializer.serialize(range.left, out, version);
serializer.serialize(range.right, out, version);
}
public AbstractBounds deserialize(DataInput in, IPartitioner p, int version) throws IOException
{
boolean isToken, startInclusive, endInclusive;
if (version < MessagingService.VERSION_30)
{
int kind = in.readInt();
isToken = kind >= 0;
if (!isToken)
kind = -(kind+1);
// Pre-3.0, everything that wasa not a Range was (wrongly) serialized as a Bound;
startInclusive = kind != Type.RANGE.ordinal();
endInclusive = true;
}
else
{
int flags = in.readUnsignedByte();
isToken = (flags & IS_TOKEN_FLAG) != 0;
startInclusive = (flags & START_INCLUSIVE_FLAG) != 0;
endInclusive = (flags & END_INCLUSIVE_FLAG) != 0;
}
T left = serializer.deserialize(in, p, version);
T right = serializer.deserialize(in, p, version);
assert isToken == left instanceof Token;
if (startInclusive)
return endInclusive ? new Bounds(left, right) : new IncludingExcludingBounds(left, right);
else
return endInclusive ? new Range(left, right) : new ExcludingBounds(left, right);
}
public long serializedSize(AbstractBounds ab, int version)
{
int size = version < MessagingService.VERSION_30
? TypeSizes.sizeof(kindInt(ab))
: 1;
size += serializer.serializedSize(ab.left, version);
size += serializer.serializedSize(ab.right, version);
return size;
}
}
public static > AbstractBounds bounds(Boundary min, Boundary max)
{
return bounds(min.boundary, min.inclusive, max.boundary, max.inclusive);
}
public static > AbstractBounds bounds(T min, boolean inclusiveMin, T max, boolean inclusiveMax)
{
if (inclusiveMin && inclusiveMax)
return new Bounds(min, max);
else if (inclusiveMax)
return new Range(min, max);
else if (inclusiveMin)
return new IncludingExcludingBounds(min, max);
else
return new ExcludingBounds(min, max);
}
// represents one side of a bounds (which side is not encoded)
public static class Boundary>
{
public final T boundary;
public final boolean inclusive;
public Boundary(T boundary, boolean inclusive)
{
this.boundary = boundary;
this.inclusive = inclusive;
}
}
public Boundary leftBoundary()
{
return new Boundary<>(left, inclusiveLeft());
}
public Boundary rightBoundary()
{
return new Boundary<>(right, inclusiveRight());
}
public static > boolean isEmpty(Boundary left, Boundary right)
{
int c = left.boundary.compareTo(right.boundary);
return c > 0 || (c == 0 && !(left.inclusive && right.inclusive));
}
public static > Boundary minRight(Boundary right1, T right2, boolean isInclusiveRight2)
{
return minRight(right1, new Boundary(right2, isInclusiveRight2));
}
public static > Boundary minRight(Boundary right1, Boundary right2)
{
int c = right1.boundary.compareTo(right2.boundary);
if (c != 0)
return c < 0 ? right1 : right2;
// return the exclusive version, if either
return right2.inclusive ? right1 : right2;
}
public static > Boundary maxLeft(Boundary left1, T left2, boolean isInclusiveLeft2)
{
return maxLeft(left1, new Boundary(left2, isInclusiveLeft2));
}
public static > Boundary maxLeft(Boundary left1, Boundary left2)
{
int c = left1.boundary.compareTo(left2.boundary);
if (c != 0)
return c > 0 ? left1 : left2;
// return the exclusive version, if either
return left2.inclusive ? left1 : left2;
}
}