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Add platform compatible implementations for Java11+
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davecromberge committed May 4, 2022
1 parent a457519 commit 00c001b5f0b17b1edd8747918913837f32567c1a
Showing 5 changed files with 214 additions and 0 deletions.
@@ -39,4 +39,22 @@
<maven.compiler.target>${java.version}</maven.compiler.target>
</properties>

<build>
<pluginManagement>
<plugins>
<plugin>
<groupId>org.apache.maven.plugins</groupId>
<artifactId>maven-compiler-plugin</artifactId>
<version>${maven-compiler-plugin.version}</version>
<configuration>
<compilerArgs>
<arg>--add-exports</arg>
<arg>java.base/jdk.internal.ref=org.apache.datasketches.memory</arg>
</compilerArgs>
</configuration>
</plugin>
</plugins>
</pluginManagement>
</build>

</project>
@@ -0,0 +1,26 @@
/*
* 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.
*/
@SuppressWarnings("javadoc")
module org.apache.datasketches.memory {
requires java.base;
requires java.logging;
requires jdk.unsupported;

exports org.apache.datasketches.memory;
}
@@ -0,0 +1,46 @@
/*
* 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.datasketches.memory;

/**
* Read only interface for a memory mapped file
*
* @author Roman Leventov
* @author Lee Rhodes
* @author Praveenkumar Venkatesan
*/
public interface Map extends AutoCloseable {

/**
* @see <a href="https://docs.oracle.com/javase/8/docs/api/java/nio/MappedByteBuffer.html#load--">
* java/nio/MappedByteBuffer.load</a>
*/
void load();

/**
* @return true if loaded
*
* @see <a href=
* "https://docs.oracle.com/javase/8/docs/api/java/nio/MappedByteBuffer.html#isLoaded--"> java
* /nio/MappedByteBuffer.isLoaded</a>
*/
boolean isLoaded();

}
@@ -0,0 +1,50 @@
/*
* 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.datasketches.memory.internal;

import jdk.internal.ref.Cleaner;

/**
* Extracts a version-dependent reference to the `jdk.internal.ref.Cleaner` into
* a standalone class. The package name for Cleaner has changed in
* later versions. The appropriate class will be loaded by the class loader
* depending on the Java version that is used.
* For more information, see: https://openjdk.java.net/jeps/238
*/
public class MemoryCleaner {
private final Cleaner cleaner;

/**
* Creates a new `jdk.internal.ref.Cleaner`.
* @param referent the object to be cleaned
* @param deallocator - the cleanup code to be run when the cleaner is invoked.
* return MemoryCleaner
*/
public MemoryCleaner(final Object referent, final Runnable deallocator) {
cleaner = Cleaner.create(referent, deallocator);
}

/**
* Runs this cleaner, if it has not been run before.
*/
public void clean() {
cleaner.clean();
}
}
@@ -0,0 +1,74 @@
/*
* 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.datasketches.memory.internal;

import java.lang.reflect.InvocationTargetException;
import java.lang.reflect.Method;

/**
* Extracts a version-dependent reference to the `jdk.internal.misc.VM` into
* a standalone class. The package name for VM has changed in
* later versions. The appropriate class will be loaded by the class loader
* depending on the Java version that is used.
* For more information, see: https://openjdk.java.net/jeps/238
*/
public final class VirtualMachineMemory {

private static final Class<?> VM_CLASS;
private static final Method VM_MAX_DIRECT_MEMORY_METHOD;
private static final Method VM_IS_DIRECT_MEMORY_PAGE_ALIGNED_METHOD;
private static final long maxDBBMemory;
private static final boolean isPageAligned;

static {
try {
VM_CLASS = Class.forName("jdk.internal.misc.VM");
VM_MAX_DIRECT_MEMORY_METHOD = VM_CLASS.getDeclaredMethod("maxDirectMemory");
VM_MAX_DIRECT_MEMORY_METHOD.setAccessible(true);
maxDBBMemory = (long) VM_MAX_DIRECT_MEMORY_METHOD.invoke(null); //static method

VM_IS_DIRECT_MEMORY_PAGE_ALIGNED_METHOD =
VM_CLASS.getDeclaredMethod("isDirectMemoryPageAligned");
VM_IS_DIRECT_MEMORY_PAGE_ALIGNED_METHOD.setAccessible(true);
isPageAligned = (boolean) VM_IS_DIRECT_MEMORY_PAGE_ALIGNED_METHOD
.invoke(null); //static method
} catch (final ClassNotFoundException | NoSuchMethodException | IllegalAccessException
| IllegalArgumentException | InvocationTargetException | SecurityException e) {
throw new RuntimeException("Could not acquire jdk.internal.misc.VM: " + e.getClass());
}
}

/**
* Returns the maximum amount of allocatable direct buffer memory.
* The directMemory variable is initialized during system initialization.
* @return the maximum amount of allocatable direct buffer memory.
*/
public static long getMaxDBBMemory() {
return maxDBBMemory;
}

/**
* Returns true if the direct buffers should be page aligned.
* @return flag that determines whether direct buffers should be page aligned.
*/
public static boolean getIsPageAligned() {
return isPageAligned;
}
}

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