/*
* Copyright 2013 The Netty Project
*
* The Netty Project 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 io.netty.util.internal;
import io.netty.util.internal.logging.InternalLogger;
import io.netty.util.internal.logging.InternalLoggerFactory;
import sun.misc.Unsafe;
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.security.AccessController;
import java.security.PrivilegedAction;
import static io.netty.util.internal.ObjectUtil.checkNotNull;
/**
* The {@link PlatformDependent} operations which requires access to {@code sun.misc.*}.
*/
final class PlatformDependent0 {
private static final InternalLogger logger = InternalLoggerFactory.getInstance(PlatformDependent0.class);
private static final long ADDRESS_FIELD_OFFSET;
private static final long BYTE_ARRAY_BASE_OFFSET;
private static final Constructor<?> DIRECT_BUFFER_CONSTRUCTOR;
private static final boolean IS_EXPLICIT_NO_UNSAFE = explicitNoUnsafe0();
private static final Method ALLOCATE_ARRAY_METHOD;
private static final Object INTERNAL_UNSAFE;
static final Unsafe UNSAFE;
// constants borrowed from murmur3
static final int HASH_CODE_ASCII_SEED = 0xc2b2ae35;
static final int HASH_CODE_C1 = 0x1b873593;
static final int HASH_CODE_C2 = 0x1b873593;
/**
* Limits the number of bytes to copy per {@link Unsafe#copyMemory(long, long, long)} to allow safepoint polling
* during a large copy.
*/
private static final long UNSAFE_COPY_THRESHOLD = 1024L * 1024L;
private static final boolean UNALIGNED;
static {
final ByteBuffer direct;
Field addressField = null;
Method allocateArrayMethod = null;
Unsafe unsafe;
Object internalUnsafe = null;
if (isExplicitNoUnsafe()) {
direct = null;
addressField = null;
unsafe = null;
internalUnsafe = null;
} else {
direct = ByteBuffer.allocateDirect(1);
// attempt to access field Unsafe#theUnsafe
final Object maybeUnsafe = AccessController.doPrivileged(new PrivilegedAction<Object>() {
@Override
public Object run() {
try {
final Field unsafeField = Unsafe.class.getDeclaredField("theUnsafe");
Throwable cause = ReflectionUtil.trySetAccessible(unsafeField);
if (cause != null) {
return cause;
}
// the unsafe instance
return unsafeField.get(null);
} catch (NoSuchFieldException e) {
return e;
} catch (SecurityException e) {
return e;
} catch (IllegalAccessException e) {
return e;
}
}
});
// the conditional check here can not be replaced with checking that maybeUnsafe
// is an instanceof Unsafe and reversing the if and else blocks; this is because an
// instanceof check against Unsafe will trigger a class load and we might not have
// the runtime permission accessClassInPackage.sun.misc
if (maybeUnsafe instanceof Exception) {
unsafe = null;
logger.debug("sun.misc.Unsafe.theUnsafe: unavailable", (Exception) maybeUnsafe);
} else {
unsafe = (Unsafe) maybeUnsafe;
logger.debug("sun.misc.Unsafe.theUnsafe: available");
}
// ensure the unsafe supports all necessary methods to work around the mistake in the latest OpenJDK
// https://github.com/netty/netty/issues/1061
// http://www.mail-archive.com/jdk6-dev@openjdk.java.net/msg00698.html
if (unsafe != null) {
final Unsafe finalUnsafe = unsafe;
final Object maybeException = AccessController.doPrivileged(new PrivilegedAction<Object>() {
@Override
public Object run() {
try {
finalUnsafe.getClass().getDeclaredMethod(
"copyMemory", Object.class, long.class, Object.class, long.class, long.class);
return null;
} catch (NoSuchMethodException e) {
return e;
} catch (SecurityException e) {
return e;
}
}
});
if (maybeException == null) {
logger.debug("sun.misc.Unsafe.copyMemory: available");
} else {
// Unsafe.copyMemory(Object, long, Object, long, long) unavailable.
unsafe = null;
logger.debug("sun.misc.Unsafe.copyMemory: unavailable", (Throwable) maybeException);
}
}
if (unsafe != null) {
final Unsafe finalUnsafe = unsafe;
// attempt to access field Buffer#address
final Object maybeAddressField = AccessController.doPrivileged(new PrivilegedAction<Object>() {
@Override
public Object run() {
try {
final Field field = Buffer.class.getDeclaredField("address");
// Use Unsafe to read value of the address field. This way it will not fail on JDK9+ which
// will forbid changing the access level via reflection.
final long offset = finalUnsafe.objectFieldOffset(field);
final long address = finalUnsafe.getLong(direct, offset);
// if direct really is a direct buffer, address will be non-zero
if (address == 0) {
return null;
}
return field;
} catch (NoSuchFieldException e) {
return e;
} catch (SecurityException e) {
return e;
}
}
});
if (maybeAddressField instanceof Field) {
addressField = (Field) maybeAddressField;
logger.debug("java.nio.Buffer.address: available");
} else {
logger.debug("java.nio.Buffer.address: unavailable", (Throwable) maybeAddressField);
// If we cannot access the address of a direct buffer, there's no point of using unsafe.
// Let's just pretend unsafe is unavailable for overall simplicity.
unsafe = null;
}
}
if (unsafe != null) {
// There are assumptions made where ever BYTE_ARRAY_BASE_OFFSET is used (equals, hashCodeAscii, and
// primitive accessors) that arrayIndexScale == 1, and results are undefined if this is not the case.
long byteArrayIndexScale = unsafe.arrayIndexScale(byte[].class);
if (byteArrayIndexScale != 1) {
logger.debug("unsafe.arrayIndexScale is {} (expected: 1). Not using unsafe.", byteArrayIndexScale);
unsafe = null;
}
}
}
UNSAFE = unsafe;
if (unsafe == null) {
ADDRESS_FIELD_OFFSET = -1;
BYTE_ARRAY_BASE_OFFSET = -1;
UNALIGNED = false;
DIRECT_BUFFER_CONSTRUCTOR = null;
ALLOCATE_ARRAY_METHOD = null;
} else {
Constructor<?> directBufferConstructor;
long address = -1;
try {
final Object maybeDirectBufferConstructor =
AccessController.doPrivileged(new PrivilegedAction<Object>() {
@Override
public Object run() {
try {
final Constructor<?> constructor =
direct.getClass().getDeclaredConstructor(long.class, int.class);
Throwable cause = ReflectionUtil.trySetAccessible(constructor);
if (cause != null) {
return cause;
}
return constructor;
} catch (NoSuchMethodException e) {
return e;
} catch (SecurityException e) {
return e;
}
}
});
if (maybeDirectBufferConstructor instanceof Constructor<?>) {
address = UNSAFE.allocateMemory(1);
// try to use the constructor now
try {
((Constructor<?>) maybeDirectBufferConstructor).newInstance(address, 1);
directBufferConstructor = (Constructor<?>) maybeDirectBufferConstructor;
logger.debug("direct buffer constructor: available");
} catch (InstantiationException e) {
directBufferConstructor = null;
} catch (IllegalAccessException e) {
directBufferConstructor = null;
} catch (InvocationTargetException e) {
directBufferConstructor = null;
}
} else {
logger.debug(
"direct buffer constructor: unavailable",
(Throwable) maybeDirectBufferConstructor);
directBufferConstructor = null;
}
} finally {
if (address != -1) {
UNSAFE.freeMemory(address);
}
}
DIRECT_BUFFER_CONSTRUCTOR = directBufferConstructor;
ADDRESS_FIELD_OFFSET = objectFieldOffset(addressField);
BYTE_ARRAY_BASE_OFFSET = UNSAFE.arrayBaseOffset(byte[].class);
boolean unaligned;
Object maybeUnaligned = AccessController.doPrivileged(new PrivilegedAction<Object>() {
@Override
public Object run() {
try {
Class<?> bitsClass =
Class.forName("java.nio.Bits", false, getSystemClassLoader());
Method unalignedMethod = bitsClass.getDeclaredMethod("unaligned");
Throwable cause = ReflectionUtil.trySetAccessible(unalignedMethod);
if (cause != null) {
return cause;
}
return unalignedMethod.invoke(null);
} catch (NoSuchMethodException e) {
return e;
} catch (SecurityException e) {
return e;
} catch (IllegalAccessException e) {
return e;
} catch (ClassNotFoundException e) {
return e;
} catch (InvocationTargetException e) {
return e;
}
}
});
if (maybeUnaligned instanceof Boolean) {
unaligned = (Boolean) maybeUnaligned;
logger.debug("java.nio.Bits.unaligned: available, {}", unaligned);
} else {
String arch = SystemPropertyUtil.get("os.arch", "");
//noinspection DynamicRegexReplaceableByCompiledPattern
unaligned = arch.matches("^(i[3-6]86|x86(_64)?|x64|amd64)$");
Throwable t = (Throwable) maybeUnaligned;
logger.debug("java.nio.Bits.unaligned: unavailable {}", unaligned, t);
}
UNALIGNED = unaligned;
Object maybeException = AccessController.doPrivileged(new PrivilegedAction<Object>() {
@Override
public Object run() {
try {
// Java9 has jdk.internal.misc.Unsafe and not all methods are propagated to
// sun.misc.Unsafe
Class<?> internalUnsafeClass = getClassLoader(PlatformDependent0.class)
.loadClass("jdk.internal.misc.Unsafe");
Method method = internalUnsafeClass.getDeclaredMethod("getUnsafe");
return method.invoke(null);
} catch (Throwable e) {
return e;
}
}
});
if (!(maybeException instanceof Throwable)) {
internalUnsafe = maybeException;
final Object finalInternalUnsafe = internalUnsafe;
maybeException = AccessController.doPrivileged(new PrivilegedAction<Object>() {
@Override
public Object run() {
try {
return finalInternalUnsafe.getClass().getDeclaredMethod(
"allocateUninitializedArray", Class.class, int.class);
} catch (NoSuchMethodException e) {
return e;
} catch (SecurityException e) {
return e;
}
}
});
if (maybeException instanceof Method) {
try {
Method m = (Method) maybeException;
byte[] bytes = (byte[]) m.invoke(finalInternalUnsafe, byte.class, 8);
assert bytes.length == 8;
allocateArrayMethod = m;
} catch (IllegalAccessException e) {
maybeException = e;
} catch (InvocationTargetException e) {
maybeException = e;
}
}
}
ALLOCATE_ARRAY_METHOD = allocateArrayMethod;
if (maybeException instanceof Throwable) {
logger.debug("jdk.internal.misc.Unsafe.allocateUninitializedArray(int): unavailable",
(Throwable) maybeException);
} else {
logger.debug("jdk.internal.misc.Unsafe.allocateUninitializedArray(int): available");
}
}
INTERNAL_UNSAFE = internalUnsafe;
logger.debug("java.nio.DirectByteBuffer.<init>(long, int): {}",
DIRECT_BUFFER_CONSTRUCTOR != null ? "available" : "unavailable");
}
static boolean isExplicitNoUnsafe() {
return IS_EXPLICIT_NO_UNSAFE;
}
private static boolean explicitNoUnsafe0() {
final boolean noUnsafe = SystemPropertyUtil.getBoolean("io.netty.noUnsafe", false);
logger.debug("-Dio.netty.noUnsafe: {}", noUnsafe);
if (noUnsafe) {
logger.debug("sun.misc.Unsafe: unavailable (io.netty.noUnsafe)");
return true;
}
// Legacy properties
boolean tryUnsafe;
if (SystemPropertyUtil.contains("io.netty.tryUnsafe")) {
tryUnsafe = SystemPropertyUtil.getBoolean("io.netty.tryUnsafe", true);
} else {
tryUnsafe = SystemPropertyUtil.getBoolean("org.jboss.netty.tryUnsafe", true);
}
if (!tryUnsafe) {
logger.debug("sun.misc.Unsafe: unavailable (io.netty.tryUnsafe/org.jboss.netty.tryUnsafe)");
return true;
}
return false;
}
static boolean isUnaligned() {
return UNALIGNED;
}
static boolean hasUnsafe() {
return UNSAFE != null;
}
static boolean unalignedAccess() {
return UNALIGNED;
}
static void throwException(Throwable cause) {
// JVM has been observed to crash when passing a null argument. See https://github.com/netty/netty/issues/4131.
UNSAFE.throwException(checkNotNull(cause, "cause"));
}
static boolean hasDirectBufferNoCleanerConstructor() {
return DIRECT_BUFFER_CONSTRUCTOR != null;
}
static ByteBuffer reallocateDirectNoCleaner(ByteBuffer buffer, int capacity) {
return newDirectBuffer(UNSAFE.reallocateMemory(directBufferAddress(buffer), capacity), capacity);
}
static ByteBuffer allocateDirectNoCleaner(int capacity) {
return newDirectBuffer(UNSAFE.allocateMemory(capacity), capacity);
}
static boolean hasAllocateArrayMethod() {
return ALLOCATE_ARRAY_METHOD != null;
}
static byte[] allocateUninitializedArray(int size) {
try {
return (byte[]) ALLOCATE_ARRAY_METHOD.invoke(INTERNAL_UNSAFE, byte.class, size);
} catch (IllegalAccessException e) {
throw new Error(e);
} catch (InvocationTargetException e) {
throw new Error(e);
}
}
static ByteBuffer newDirectBuffer(long address, int capacity) {
ObjectUtil.checkPositiveOrZero(capacity, "capacity");
try {
return (ByteBuffer) DIRECT_BUFFER_CONSTRUCTOR.newInstance(address, capacity);
} catch (Throwable cause) {
// Not expected to ever throw!
if (cause instanceof Error) {
throw (Error) cause;
}
throw new Error(cause);
}
}
static long directBufferAddress(ByteBuffer buffer) {
return getLong(buffer, ADDRESS_FIELD_OFFSET);
}
static long byteArrayBaseOffset() {
return BYTE_ARRAY_BASE_OFFSET;
}
static Object getObject(Object object, long fieldOffset) {
return UNSAFE.getObject(object, fieldOffset);
}
static int getInt(Object object, long fieldOffset) {
return UNSAFE.getInt(object, fieldOffset);
}
private static long getLong(Object object, long fieldOffset) {
return UNSAFE.getLong(object, fieldOffset);
}
static long objectFieldOffset(Field field) {
return UNSAFE.objectFieldOffset(field);
}
static byte getByte(long address) {
return UNSAFE.getByte(address);
}
static short getShort(long address) {
return UNSAFE.getShort(address);
}
static int getInt(long address) {
return UNSAFE.getInt(address);
}
static long getLong(long address) {
return UNSAFE.getLong(address);
}
static byte getByte(byte[] data, int index) {
return UNSAFE.getByte(data, BYTE_ARRAY_BASE_OFFSET + index);
}
static short getShort(byte[] data, int index) {
return UNSAFE.getShort(data, BYTE_ARRAY_BASE_OFFSET + index);
}
static int getInt(byte[] data, int index) {
return UNSAFE.getInt(data, BYTE_ARRAY_BASE_OFFSET + index);
}
static long getLong(byte[] data, int index) {
return UNSAFE.getLong(data, BYTE_ARRAY_BASE_OFFSET + index);
}
static void putByte(long address, byte value) {
UNSAFE.putByte(address, value);
}
static void putShort(long address, short value) {
UNSAFE.putShort(address, value);
}
static void putInt(long address, int value) {
UNSAFE.putInt(address, value);
}
static void putLong(long address, long value) {
UNSAFE.putLong(address, value);
}
static void putByte(byte[] data, int index, byte value) {
UNSAFE.putByte(data, BYTE_ARRAY_BASE_OFFSET + index, value);
}
static void putShort(byte[] data, int index, short value) {
UNSAFE.putShort(data, BYTE_ARRAY_BASE_OFFSET + index, value);
}
static void putInt(byte[] data, int index, int value) {
UNSAFE.putInt(data, BYTE_ARRAY_BASE_OFFSET + index, value);
}
static void putLong(byte[] data, int index, long value) {
UNSAFE.putLong(data, BYTE_ARRAY_BASE_OFFSET + index, value);
}
static void copyMemory(long srcAddr, long dstAddr, long length) {
//UNSAFE.copyMemory(srcAddr, dstAddr, length);
while (length > 0) {
long size = Math.min(length, UNSAFE_COPY_THRESHOLD);
UNSAFE.copyMemory(srcAddr, dstAddr, size);
length -= size;
srcAddr += size;
dstAddr += size;
}
}
static void copyMemory(Object src, long srcOffset, Object dst, long dstOffset, long length) {
//UNSAFE.copyMemory(src, srcOffset, dst, dstOffset, length);
while (length > 0) {
long size = Math.min(length, UNSAFE_COPY_THRESHOLD);
UNSAFE.copyMemory(src, srcOffset, dst, dstOffset, size);
length -= size;
srcOffset += size;
dstOffset += size;
}
}
static void setMemory(long address, long bytes, byte value) {
UNSAFE.setMemory(address, bytes, value);
}
static void setMemory(Object o, long offset, long bytes, byte value) {
UNSAFE.setMemory(o, offset, bytes, value);
}
static boolean equals(byte[] bytes1, int startPos1, byte[] bytes2, int startPos2, int length) {
if (length <= 0) {
return true;
}
final long baseOffset1 = BYTE_ARRAY_BASE_OFFSET + startPos1;
final long baseOffset2 = BYTE_ARRAY_BASE_OFFSET + startPos2;
int remainingBytes = length & 7;
final long end = baseOffset1 + remainingBytes;
for (long i = baseOffset1 - 8 + length, j = baseOffset2 - 8 + length; i >= end; i -= 8, j -= 8) {
if (UNSAFE.getLong(bytes1, i) != UNSAFE.getLong(bytes2, j)) {
return false;
}
}
if (remainingBytes >= 4) {
remainingBytes -= 4;
if (UNSAFE.getInt(bytes1, baseOffset1 + remainingBytes) !=
UNSAFE.getInt(bytes2, baseOffset2 + remainingBytes)) {
return false;
}
}
if (remainingBytes >= 2) {
return UNSAFE.getChar(bytes1, baseOffset1) == UNSAFE.getChar(bytes2, baseOffset2) &&
(remainingBytes == 2 || bytes1[startPos1 + 2] == bytes2[startPos2 + 2]);
}
return bytes1[startPos1] == bytes2[startPos2];
}
static int equalsConstantTime(byte[] bytes1, int startPos1, byte[] bytes2, int startPos2, int length) {
long result = 0;
final long baseOffset1 = BYTE_ARRAY_BASE_OFFSET + startPos1;
final long baseOffset2 = BYTE_ARRAY_BASE_OFFSET + startPos2;
final int remainingBytes = length & 7;
final long end = baseOffset1 + remainingBytes;
for (long i = baseOffset1 - 8 + length, j = baseOffset2 - 8 + length; i >= end; i -= 8, j -= 8) {
result |= UNSAFE.getLong(bytes1, i) ^ UNSAFE.getLong(bytes2, j);
}
switch (remainingBytes) {
case 7:
return ConstantTimeUtils.equalsConstantTime(result |
(UNSAFE.getInt(bytes1, baseOffset1 + 3) ^ UNSAFE.getInt(bytes2, baseOffset2 + 3)) |
(UNSAFE.getChar(bytes1, baseOffset1 + 1) ^ UNSAFE.getChar(bytes2, baseOffset2 + 1)) |
(UNSAFE.getByte(bytes1, baseOffset1) ^ UNSAFE.getByte(bytes2, baseOffset2)), 0);
case 6:
return ConstantTimeUtils.equalsConstantTime(result |
(UNSAFE.getInt(bytes1, baseOffset1 + 2) ^ UNSAFE.getInt(bytes2, baseOffset2 + 2)) |
(UNSAFE.getChar(bytes1, baseOffset1) ^ UNSAFE.getChar(bytes2, baseOffset2)), 0);
case 5:
return ConstantTimeUtils.equalsConstantTime(result |
(UNSAFE.getInt(bytes1, baseOffset1 + 1) ^ UNSAFE.getInt(bytes2, baseOffset2 + 1)) |
(UNSAFE.getByte(bytes1, baseOffset1) ^ UNSAFE.getByte(bytes2, baseOffset2)), 0);
case 4:
return ConstantTimeUtils.equalsConstantTime(result |
(UNSAFE.getInt(bytes1, baseOffset1) ^ UNSAFE.getInt(bytes2, baseOffset2)), 0);
case 3:
return ConstantTimeUtils.equalsConstantTime(result |
(UNSAFE.getChar(bytes1, baseOffset1 + 1) ^ UNSAFE.getChar(bytes2, baseOffset2 + 1)) |
(UNSAFE.getByte(bytes1, baseOffset1) ^ UNSAFE.getByte(bytes2, baseOffset2)), 0);
case 2:
return ConstantTimeUtils.equalsConstantTime(result |
(UNSAFE.getChar(bytes1, baseOffset1) ^ UNSAFE.getChar(bytes2, baseOffset2)), 0);
case 1:
return ConstantTimeUtils.equalsConstantTime(result |
(UNSAFE.getByte(bytes1, baseOffset1) ^ UNSAFE.getByte(bytes2, baseOffset2)), 0);
default:
return ConstantTimeUtils.equalsConstantTime(result, 0);
}
}
static boolean isZero(byte[] bytes, int startPos, int length) {
if (length <= 0) {
return true;
}
final long baseOffset = BYTE_ARRAY_BASE_OFFSET + startPos;
int remainingBytes = length & 7;
final long end = baseOffset + remainingBytes;
for (long i = baseOffset - 8 + length; i >= end; i -= 8) {
if (UNSAFE.getLong(bytes, i) != 0) {
return false;
}
}
if (remainingBytes >= 4) {
remainingBytes -= 4;
if (UNSAFE.getInt(bytes, baseOffset + remainingBytes) != 0) {
return false;
}
}
if (remainingBytes >= 2) {
return UNSAFE.getChar(bytes, baseOffset) == 0 &&
(remainingBytes == 2 || bytes[startPos + 2] == 0);
}
return bytes[startPos] == 0;
}
static int hashCodeAscii(byte[] bytes, int startPos, int length) {
int hash = HASH_CODE_ASCII_SEED;
final long baseOffset = BYTE_ARRAY_BASE_OFFSET + startPos;
final int remainingBytes = length & 7;
final long end = baseOffset + remainingBytes;
for (long i = baseOffset - 8 + length; i >= end; i -= 8) {
hash = hashCodeAsciiCompute(UNSAFE.getLong(bytes, i), hash);
}
switch(remainingBytes) {
case 7:
return ((hash * HASH_CODE_C1 + hashCodeAsciiSanitize(UNSAFE.getByte(bytes, baseOffset)))
* HASH_CODE_C2 + hashCodeAsciiSanitize(UNSAFE.getShort(bytes, baseOffset + 1)))
* HASH_CODE_C1 + hashCodeAsciiSanitize(UNSAFE.getInt(bytes, baseOffset + 3));
case 6:
return (hash * HASH_CODE_C1 + hashCodeAsciiSanitize(UNSAFE.getShort(bytes, baseOffset)))
* HASH_CODE_C2 + hashCodeAsciiSanitize(UNSAFE.getInt(bytes, baseOffset + 2));
case 5:
return (hash * HASH_CODE_C1 + hashCodeAsciiSanitize(UNSAFE.getByte(bytes, baseOffset)))
* HASH_CODE_C2 + hashCodeAsciiSanitize(UNSAFE.getInt(bytes, baseOffset + 1));
case 4:
return hash * HASH_CODE_C1 + hashCodeAsciiSanitize(UNSAFE.getInt(bytes, baseOffset));
case 3:
return (hash * HASH_CODE_C1 + hashCodeAsciiSanitize(UNSAFE.getByte(bytes, baseOffset)))
* HASH_CODE_C2 + hashCodeAsciiSanitize(UNSAFE.getShort(bytes, baseOffset + 1));
case 2:
return hash * HASH_CODE_C1 + hashCodeAsciiSanitize(UNSAFE.getShort(bytes, baseOffset));
case 1:
return hash * HASH_CODE_C1 + hashCodeAsciiSanitize(UNSAFE.getByte(bytes, baseOffset));
default:
return hash;
}
}
static int hashCodeAsciiCompute(long value, int hash) {
// masking with 0x1f reduces the number of overall bits that impact the hash code but makes the hash
// code the same regardless of character case (upper case or lower case hash is the same).
return hash * HASH_CODE_C1 +
// Low order int
hashCodeAsciiSanitize((int) value) * HASH_CODE_C2 +
// High order int
(int) ((value & 0x1f1f1f1f00000000L) >>> 32);
}
static int hashCodeAsciiSanitize(int value) {
return value & 0x1f1f1f1f;
}
static int hashCodeAsciiSanitize(short value) {
return value & 0x1f1f;
}
static int hashCodeAsciiSanitize(byte value) {
return value & 0x1f;
}
static ClassLoader getClassLoader(final Class<?> clazz) {
if (System.getSecurityManager() == null) {
return clazz.getClassLoader();
} else {
return AccessController.doPrivileged(new PrivilegedAction<ClassLoader>() {
@Override
public ClassLoader run() {
return clazz.getClassLoader();
}
});
}
}
static ClassLoader getContextClassLoader() {
if (System.getSecurityManager() == null) {
return Thread.currentThread().getContextClassLoader();
} else {
return AccessController.doPrivileged(new PrivilegedAction<ClassLoader>() {
@Override
public ClassLoader run() {
return Thread.currentThread().getContextClassLoader();
}
});
}
}
static ClassLoader getSystemClassLoader() {
if (System.getSecurityManager() == null) {
return ClassLoader.getSystemClassLoader();
} else {
return AccessController.doPrivileged(new PrivilegedAction<ClassLoader>() {
@Override
public ClassLoader run() {
return ClassLoader.getSystemClassLoader();
}
});
}
}
static int addressSize() {
return UNSAFE.addressSize();
}
static long allocateMemory(long size) {
return UNSAFE.allocateMemory(size);
}
static void freeMemory(long address) {
UNSAFE.freeMemory(address);
}
static long reallocateMemory(long address, long newSize) {
return UNSAFE.reallocateMemory(address, newSize);
}
private PlatformDependent0() {
}
}