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A fork of the Apache Cassandra Project ready to embed Elasticsearch.
/*
* 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.io.util;
import net.nicoulaj.compilecommand.annotations.Inline;
import org.apache.cassandra.utils.concurrent.Ref;
import org.apache.cassandra.utils.concurrent.RefCounted;
import org.apache.cassandra.utils.concurrent.SharedCloseable;
import org.apache.cassandra.utils.memory.MemoryUtil;
public class SafeMemory extends Memory implements SharedCloseable
{
private final Ref ref;
public SafeMemory(long size)
{
super(size);
ref = new Ref<>(null, new MemoryTidy(peer, size));
}
private SafeMemory(SafeMemory copyOf)
{
super(copyOf);
ref = copyOf.ref.ref();
/** see {@link Memory#Memory(long)} re: null pointers*/
if (peer == 0 && size != 0)
{
ref.ensureReleased();
throw new IllegalStateException("Cannot create a sharedCopy of a SafeMemory object that has already been closed");
}
}
public SafeMemory sharedCopy()
{
return new SafeMemory(this);
}
public void free()
{
ref.release();
peer = 0;
}
public void close()
{
ref.ensureReleased();
peer = 0;
}
public Throwable close(Throwable accumulate)
{
return ref.ensureReleased(accumulate);
}
public SafeMemory copy(long newSize)
{
SafeMemory copy = new SafeMemory(newSize);
copy.put(0, this, 0, Math.min(size(), newSize));
return copy;
}
private static final class MemoryTidy implements RefCounted.Tidy
{
final long peer;
final long size;
private MemoryTidy(long peer, long size)
{
this.peer = peer;
this.size = size;
}
public void tidy() throws Exception
{
/** see {@link Memory#Memory(long)} re: null pointers*/
if (peer != 0)
MemoryUtil.free(peer);
}
public String name()
{
return Memory.toString(peer, size);
}
}
@Inline
protected void checkBounds(long start, long end)
{
assert peer != 0 || size == 0 : ref.printDebugInfo();
super.checkBounds(start, end);
}
public void addTo(Ref.IdentityCollection identities)
{
identities.add(ref);
}
}