org.xerial.snappy.pure.UnsafeUtil Maven / Gradle / Ivy
/*
* 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 org.xerial.snappy.pure;
import org.xerial.snappy.SnappyError;
import org.xerial.snappy.SnappyErrorCode;
import sun.misc.Unsafe;
import java.lang.reflect.Field;
import java.nio.Buffer;
final class UnsafeUtil
{
public static final Unsafe UNSAFE;
private static final Field ADDRESS_ACCESSOR;
private UnsafeUtil()
{
}
static {
try {
Field theUnsafe = Unsafe.class.getDeclaredField("theUnsafe");
theUnsafe.setAccessible(true);
UNSAFE = (Unsafe) theUnsafe.get(null);
}
catch (Exception e) {
throw new SnappyError(SnappyErrorCode.UNSUPPORTED_PLATFORM, "pure-java snappy requires access to sun.misc.Unsafe");
}
try {
Field field = Buffer.class.getDeclaredField("address");
field.setAccessible(true);
ADDRESS_ACCESSOR = field;
}
catch (Exception e) {
throw new SnappyError(SnappyErrorCode.UNSUPPORTED_PLATFORM, "pure-java snappy requires access to java.nio.Buffer raw address field");
}
}
public static long getAddress(Buffer buffer)
{
try {
return (long) ADDRESS_ACCESSOR.get(buffer);
}
catch (IllegalAccessException e) {
throw new RuntimeException(e);
}
}
}