| /* |
| * 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.serializers; |
| |
| import java.nio.BufferUnderflowException; |
| import java.nio.ByteBuffer; |
| |
| import com.google.common.collect.Range; |
| |
| import org.apache.cassandra.db.marshal.AbstractType; |
| import org.apache.cassandra.db.marshal.ByteBufferAccessor; |
| import org.apache.cassandra.utils.ByteBufferUtil; |
| |
| /** |
| * Common superclass for {@link SetSerializer} and {@link MapSerializer}, considering a set as a map without values. |
| */ |
| abstract class AbstractMapSerializer<T> extends CollectionSerializer<T> |
| { |
| private final boolean hasValues; |
| private final String name; |
| |
| protected AbstractMapSerializer(boolean hasValues) |
| { |
| this.hasValues = hasValues; |
| name = hasValues ? "map" : "set"; |
| } |
| |
| @Override |
| public ByteBuffer getSliceFromSerialized(ByteBuffer collection, |
| ByteBuffer from, |
| ByteBuffer to, |
| AbstractType<?> comparator, |
| boolean frozen) |
| { |
| if (from == ByteBufferUtil.UNSET_BYTE_BUFFER && to == ByteBufferUtil.UNSET_BYTE_BUFFER) |
| return collection; |
| |
| try |
| { |
| ByteBuffer input = collection.duplicate(); |
| int n = readCollectionSize(input, ByteBufferAccessor.instance); |
| input.position(input.position() + sizeOfCollectionSize()); |
| int startPos = input.position(); |
| int count = 0; |
| boolean inSlice = from == ByteBufferUtil.UNSET_BYTE_BUFFER; |
| |
| for (int i = 0; i < n; i++) |
| { |
| int pos = input.position(); |
| ByteBuffer key = readValue(input, ByteBufferAccessor.instance, 0); |
| input.position(input.position() + sizeOfValue(key, ByteBufferAccessor.instance)); |
| |
| // If we haven't passed the start already, check if we have now |
| if (!inSlice) |
| { |
| int comparison = comparator.compareForCQL(from, key); |
| if (comparison <= 0) |
| { |
| // We're now within the slice |
| inSlice = true; |
| startPos = pos; |
| } |
| else |
| { |
| // We're before the slice, so we know we don't care about this element |
| skipMapValue(input); |
| continue; |
| } |
| } |
| |
| // Now check if we're done |
| int comparison = to == ByteBufferUtil.UNSET_BYTE_BUFFER ? -1 : comparator.compareForCQL(key, to); |
| if (comparison > 0) |
| { |
| // We're done and shouldn't include the key we just read |
| input.position(pos); |
| break; |
| } |
| |
| // Otherwise, we'll include that element |
| skipMapValue(input); // value |
| ++count; |
| |
| // But if we know it was the last of the slice, we break early |
| if (comparison == 0) |
| break; |
| } |
| |
| if (count == 0 && !frozen) |
| return null; |
| |
| return copyAsNewCollection(collection, count, startPos, input.position()); |
| } |
| catch (BufferUnderflowException | IndexOutOfBoundsException e) |
| { |
| throw new MarshalException("Not enough bytes to read a " + name); |
| } |
| } |
| |
| @Override |
| public int getIndexFromSerialized(ByteBuffer collection, ByteBuffer key, AbstractType<?> comparator) |
| { |
| try |
| { |
| ByteBuffer input = collection.duplicate(); |
| int n = readCollectionSize(input, ByteBufferAccessor.instance); |
| int offset = sizeOfCollectionSize(); |
| for (int i = 0; i < n; i++) |
| { |
| ByteBuffer kbb = readValue(input, ByteBufferAccessor.instance, offset); |
| offset += sizeOfValue(kbb, ByteBufferAccessor.instance); |
| int comparison = comparator.compareForCQL(kbb, key); |
| |
| if (comparison == 0) |
| return i; |
| |
| if (comparison > 0) |
| // since the set is in sorted order, we know we've gone too far and the element doesn't exist |
| return -1; |
| |
| // comparison < 0 |
| if (hasValues) |
| offset += skipValue(input, ByteBufferAccessor.instance, offset); |
| } |
| return -1; |
| } |
| catch (BufferUnderflowException e) |
| { |
| throw new MarshalException("Not enough bytes to read a " + name); |
| } |
| } |
| |
| @Override |
| public Range<Integer> getIndexesRangeFromSerialized(ByteBuffer collection, |
| ByteBuffer from, |
| ByteBuffer to, |
| AbstractType<?> comparator) |
| { |
| if (from == ByteBufferUtil.UNSET_BYTE_BUFFER && to == ByteBufferUtil.UNSET_BYTE_BUFFER) |
| return Range.closed(0, Integer.MAX_VALUE); |
| |
| try |
| { |
| ByteBuffer input = collection.duplicate(); |
| int n = readCollectionSize(input, ByteBufferAccessor.instance); |
| input.position(input.position() + sizeOfCollectionSize()); |
| int start = from == ByteBufferUtil.UNSET_BYTE_BUFFER ? 0 : -1; |
| int end = to == ByteBufferUtil.UNSET_BYTE_BUFFER ? n : -1; |
| |
| for (int i = 0; i < n; i++) |
| { |
| if (start >= 0 && end >= 0) |
| break; |
| else if (i > 0) |
| skipMapValue(input); |
| |
| ByteBuffer key = readValue(input, ByteBufferAccessor.instance, 0); |
| input.position(input.position() + sizeOfValue(key, ByteBufferAccessor.instance)); |
| |
| if (start < 0) |
| { |
| int comparison = comparator.compareForCQL(from, key); |
| if (comparison <= 0) |
| start = i; |
| else |
| continue; |
| } |
| |
| if (end < 0) |
| { |
| int comparison = comparator.compareForCQL(key, to); |
| if (comparison > 0) |
| end = i; |
| } |
| } |
| |
| if (start < 0) |
| return Range.closedOpen(0, 0); |
| |
| if (end < 0) |
| return Range.closedOpen(start, n); |
| |
| return Range.closedOpen(start, end); |
| } |
| catch (BufferUnderflowException e) |
| { |
| throw new MarshalException("Not enough bytes to read a " + name); |
| } |
| } |
| |
| private void skipMapValue(ByteBuffer input) |
| { |
| if (hasValues) |
| skipValue(input); |
| } |
| } |