ascherbakoff commented on a change in pull request #82: URL: https://github.com/apache/ignite-3/pull/82#discussion_r609717385
########## File path: modules/core/src/main/java/org/apache/ignite/internal/util/GridUnsafe.java ########## @@ -0,0 +1,2014 @@ +/* + * 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.ignite.internal.util; + +import java.lang.reflect.Constructor; +import java.lang.reflect.Field; +import java.lang.reflect.InvocationTargetException; +import java.lang.reflect.Method; +import java.nio.Buffer; +import java.nio.ByteBuffer; +import java.nio.ByteOrder; +import java.security.AccessController; +import java.security.PrivilegedAction; +import java.security.PrivilegedActionException; +import java.security.PrivilegedExceptionAction; +import org.jetbrains.annotations.NotNull; +import org.jetbrains.annotations.Nullable; +import sun.misc.Unsafe; + +import static org.apache.ignite.internal.util.IgniteUtils.jdkVersion; +import static org.apache.ignite.internal.util.IgniteUtils.majorJavaVersion; + +/** + * <p>Wrapper for {@link sun.misc.Unsafe} class.</p> + * + * <p> + * The following statements for memory access operations are true: + * <ul> + * <li>All {@code putXxx(long addr, xxx val)}, {@code getXxx(long addr)}, {@code putXxx(byte[] arr, long off, xxx val)}, + * {@code getXxx(byte[] arr, long off)} and corresponding methods with {@code LE} suffix are alignment aware + * and can be safely used with unaligned pointers.</li> + * <li>All {@code putXxxField(Object obj, long fieldOff, xxx val)} and {@code getXxxField(Object obj, long fieldOff)} + * methods are not alignment aware and can't be safely used with unaligned pointers. This methods can be safely used + * for object field values access because all object fields addresses are aligned.</li> + * <li>All {@code putXxxLE(...)} and {@code getXxxLE(...)} methods assumes that byte order is fixed as little-endian + * while native byte order is big-endian. So it is client code responsibility to check native byte order before + * invoking of this methods.</li> + * </ul> + * </p> + */ +public abstract class GridUnsafe { + /** */ + public static final ByteOrder NATIVE_BYTE_ORDER = ByteOrder.nativeOrder(); + + /** Unsafe. */ + private static final Unsafe UNSAFE = unsafe(); + + /** Unaligned flag. */ + private static final boolean UNALIGNED = unaligned(); + + /** Per-byte copy threshold. */ + private static final long PER_BYTE_THRESHOLD = 0L; + + /** Big endian. */ + public static final boolean BIG_ENDIAN = ByteOrder.nativeOrder() == ByteOrder.BIG_ENDIAN; + + /** Address size. */ + public static final int ADDR_SIZE = UNSAFE.addressSize(); + + /** */ + public static final long BYTE_ARR_OFF = UNSAFE.arrayBaseOffset(byte[].class); + + /** */ + public static final int BYTE_ARR_INT_OFF = UNSAFE.arrayBaseOffset(byte[].class); + + /** */ + public static final long SHORT_ARR_OFF = UNSAFE.arrayBaseOffset(short[].class); + + /** */ + public static final long INT_ARR_OFF = UNSAFE.arrayBaseOffset(int[].class); + + /** */ + public static final long LONG_ARR_OFF = UNSAFE.arrayBaseOffset(long[].class); + + /** */ + public static final long FLOAT_ARR_OFF = UNSAFE.arrayBaseOffset(float[].class); + + /** */ + public static final long DOUBLE_ARR_OFF = UNSAFE.arrayBaseOffset(double[].class); + + /** */ + public static final long CHAR_ARR_OFF = UNSAFE.arrayBaseOffset(char[].class); + + /** */ + public static final long BOOLEAN_ARR_OFF = UNSAFE.arrayBaseOffset(boolean[].class); + + /** {@link java.nio.Buffer#address} field offset. */ + private static final long DIRECT_BUF_ADDR_OFF = bufferAddressOffset(); + + /** Cleaner code for direct {@code java.nio.ByteBuffer}. */ + private static final DirectBufferCleaner DIRECT_BUF_CLEANER = + majorJavaVersion(jdkVersion()) < 9 + ? new ReflectiveDirectBufferCleaner() + : new UnsafeDirectBufferCleaner(); + + /** JavaNioAccess object. If {@code null} then {@link #NEW_DIRECT_BUF_CONSTRUCTOR} should be available. */ + @Nullable private static final Object JAVA_NIO_ACCESS_OBJ; + + /** + * JavaNioAccess#newDirectByteBuffer method. Ususally {@code null} if {@link #JAVA_NIO_ACCESS_OBJ} is {@code null}. + * If {@code null} then {@link #NEW_DIRECT_BUF_CONSTRUCTOR} should be available. + */ + @Nullable private static final Method NEW_DIRECT_BUF_MTD; + + /** + * New direct buffer class constructor obtained and tested using reflection. If {@code null} then both {@link + * #JAVA_NIO_ACCESS_OBJ} and {@link #NEW_DIRECT_BUF_MTD} should be not {@code null}. + */ + @Nullable private static final Constructor<?> NEW_DIRECT_BUF_CONSTRUCTOR; + + static { + Object nioAccessObj = null; + Method directBufMtd = null; + + Constructor<?> directBufCtor = null; + + if (majorJavaVersion(jdkVersion()) < 12) { + // for old java prefer Java NIO & Shared Secrets obect init way + try { + nioAccessObj = javaNioAccessObject(); + directBufMtd = newDirectBufferMethod(nioAccessObj); + } + catch (Exception e) { + nioAccessObj = null; + directBufMtd = null; + + try { + directBufCtor = createAndTestNewDirectBufferCtor(); + } + catch (Exception eFallback) { + //noinspection CallToPrintStackTrace + eFallback.printStackTrace(); Review comment: Can you clarify the purpose ? Just curious. -- This is an automated message from the Apache Git Service. To respond to the message, please log on to GitHub and use the URL above to go to the specific comment. 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