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Diffstat (limited to 'src/Java/shaded/reflectionfactory/Unsafe.java')
| -rw-r--r-- | src/Java/shaded/reflectionfactory/Unsafe.java | 1146 |
1 files changed, 0 insertions, 1146 deletions
diff --git a/src/Java/shaded/reflectionfactory/Unsafe.java b/src/Java/shaded/reflectionfactory/Unsafe.java deleted file mode 100644 index 77539b0594..0000000000 --- a/src/Java/shaded/reflectionfactory/Unsafe.java +++ /dev/null @@ -1,1146 +0,0 @@ -/* - * Copyright (c) 2000, 2013, Oracle and/or its affiliates. All rights reserved. - * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER. - * - * This code is free software; you can redistribute it and/or modify it - * under the terms of the GNU General Public License version 2 only, as - * published by the Free Software Foundation. Oracle designates this - * particular file as subject to the "Classpath" exception as provided - * by Oracle in the LICENSE file that accompanied this code. - * - * This code is distributed in the hope that it will be useful, but WITHOUT - * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or - * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License - * version 2 for more details (a copy is included in the LICENSE file that - * accompanied this code). - * - * You should have received a copy of the GNU General Public License version - * 2 along with this work; if not, write to the Free Software Foundation, - * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA. - * - * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA - * or visit www.oracle.com if you need additional information or have any - * questions. - */ - -package shaded.reflectionfactory; - -import java.security.*; - -import shaded.reflectionfactory.CallerSensitive; -import shaded.reflectionfactory.Reflection; - -import java.lang.reflect.*; - - -/** - * A collection of methods for performing low-level, unsafe operations. - * Although the class and all methods are public, use of this class is - * limited because only trusted code can obtain instances of it. - * - * @author John R. Rose - * @see #getUnsafe - */ - -public final class Unsafe { - - private static native void registerNatives(); - static { - registerNatives(); - shaded.reflectionfactory.Reflection.registerMethodsToFilter(Unsafe.class, "getUnsafe"); - } - - private Unsafe() {} - - private static final Unsafe theUnsafe = new Unsafe(); - - /** - * Provides the caller with the capability of performing unsafe - * operations. - * - * <p> The returned <code>Unsafe</code> object should be carefully guarded - * by the caller, since it can be used to read and write data at arbitrary - * memory addresses. It must never be passed to untrusted code. - * - * <p> Most methods in this class are very low-level, and correspond to a - * small number of hardware instructions (on typical machines). Compilers - * are encouraged to optimize these methods accordingly. - * - * <p> Here is a suggested idiom for using unsafe operations: - * - * <blockquote><pre> - * class MyTrustedClass { - * private static final Unsafe unsafe = Unsafe.getUnsafe(); - * ... - * private long myCountAddress = ...; - * public int getCount() { return unsafe.getByte(myCountAddress); } - * } - * </pre></blockquote> - * - * (It may assist compilers to make the local variable be - * <code>final</code>.) - * - * @exception SecurityException if a security manager exists and its - * <code>checkPropertiesAccess</code> method doesn't allow - * access to the system properties. - */ - @CallerSensitive - public static Unsafe getUnsafe() { - Class<?> caller = Reflection.getCallerClass(); - if (!Reflection.isSystemDomainLoader(caller.getClassLoader())) - throw new SecurityException("Unsafe"); - return theUnsafe; - } - - /// peek and poke operations - /// (compilers should optimize these to memory ops) - - // These work on object fields in the Java heap. - // They will not work on elements of packed arrays. - - /** - * Fetches a value from a given Java variable. - * More specifically, fetches a field or array element within the given - * object <code>o</code> at the given offset, or (if <code>o</code> is - * null) from the memory address whose numerical value is the given - * offset. - * <p> - * The results are undefined unless one of the following cases is true: - * <ul> - * <li>The offset was obtained from {@link #objectFieldOffset} on - * the {@link java.lang.reflect.Field} of some Java field and the object - * referred to by <code>o</code> is of a class compatible with that - * field's class. - * - * <li>The offset and object reference <code>o</code> (either null or - * non-null) were both obtained via {@link #staticFieldOffset} - * and {@link #staticFieldBase} (respectively) from the - * reflective {@link Field} representation of some Java field. - * - * <li>The object referred to by <code>o</code> is an array, and the offset - * is an integer of the form <code>B+N*S</code>, where <code>N</code> is - * a valid index into the array, and <code>B</code> and <code>S</code> are - * the values obtained by {@link #arrayBaseOffset} and {@link - * #arrayIndexScale} (respectively) from the array's class. The value - * referred to is the <code>N</code><em>th</em> element of the array. - * - * </ul> - * <p> - * If one of the above cases is true, the call references a specific Java - * variable (field or array element). However, the results are undefined - * if that variable is not in fact of the type returned by this method. - * <p> - * This method refers to a variable by means of two parameters, and so - * it provides (in effect) a <em>double-register</em> addressing mode - * for Java variables. When the object reference is null, this method - * uses its offset as an absolute address. This is similar in operation - * to methods such as {@link #getInt(long)}, which provide (in effect) a - * <em>single-register</em> addressing mode for non-Java variables. - * However, because Java variables may have a different layout in memory - * from non-Java variables, programmers should not assume that these - * two addressing modes are ever equivalent. Also, programmers should - * remember that offsets from the double-register addressing mode cannot - * be portably confused with longs used in the single-register addressing - * mode. - * - * @param o Java heap object in which the variable resides, if any, else - * null - * @param offset indication of where the variable resides in a Java heap - * object, if any, else a memory address locating the variable - * statically - * @return the value fetched from the indicated Java variable - * @throws RuntimeException No defined exceptions are thrown, not even - * {@link NullPointerException} - */ - public native int getInt(Object o, long offset); - - /** - * Stores a value into a given Java variable. - * <p> - * The first two parameters are interpreted exactly as with - * {@link #getInt(Object, long)} to refer to a specific - * Java variable (field or array element). The given value - * is stored into that variable. - * <p> - * The variable must be of the same type as the method - * parameter <code>x</code>. - * - * @param o Java heap object in which the variable resides, if any, else - * null - * @param offset indication of where the variable resides in a Java heap - * object, if any, else a memory address locating the variable - * statically - * @param x the value to store into the indicated Java variable - * @throws RuntimeException No defined exceptions are thrown, not even - * {@link NullPointerException} - */ - public native void putInt(Object o, long offset, int x); - - /** - * Fetches a reference value from a given Java variable. - * @see #getInt(Object, long) - */ - public native Object getObject(Object o, long offset); - - /** - * Stores a reference value into a given Java variable. - * <p> - * Unless the reference <code>x</code> being stored is either null - * or matches the field type, the results are undefined. - * If the reference <code>o</code> is non-null, car marks or - * other store barriers for that object (if the VM requires them) - * are updated. - * @see #putInt(Object, int, int) - */ - public native void putObject(Object o, long offset, Object x); - - /** @see #getInt(Object, long) */ - public native boolean getBoolean(Object o, long offset); - /** @see #putInt(Object, int, int) */ - public native void putBoolean(Object o, long offset, boolean x); - /** @see #getInt(Object, long) */ - public native byte getByte(Object o, long offset); - /** @see #putInt(Object, int, int) */ - public native void putByte(Object o, long offset, byte x); - /** @see #getInt(Object, long) */ - public native short getShort(Object o, long offset); - /** @see #putInt(Object, int, int) */ - public native void putShort(Object o, long offset, short x); - /** @see #getInt(Object, long) */ - public native char getChar(Object o, long offset); - /** @see #putInt(Object, int, int) */ - public native void putChar(Object o, long offset, char x); - /** @see #getInt(Object, long) */ - public native long getLong(Object o, long offset); - /** @see #putInt(Object, int, int) */ - public native void putLong(Object o, long offset, long x); - /** @see #getInt(Object, long) */ - public native float getFloat(Object o, long offset); - /** @see #putInt(Object, int, int) */ - public native void putFloat(Object o, long offset, float x); - /** @see #getInt(Object, long) */ - public native double getDouble(Object o, long offset); - /** @see #putInt(Object, int, int) */ - public native void putDouble(Object o, long offset, double x); - - /** - * This method, like all others with 32-bit offsets, was native - * in a previous release but is now a wrapper which simply casts - * the offset to a long value. It provides backward compatibility - * with bytecodes compiled against 1.4. - * @deprecated As of 1.4.1, cast the 32-bit offset argument to a long. - * See {@link #staticFieldOffset}. - */ - @Deprecated - public int getInt(Object o, int offset) { - return getInt(o, (long)offset); - } - - /** - * @deprecated As of 1.4.1, cast the 32-bit offset argument to a long. - * See {@link #staticFieldOffset}. - */ - @Deprecated - public void putInt(Object o, int offset, int x) { - putInt(o, (long)offset, x); - } - - /** - * @deprecated As of 1.4.1, cast the 32-bit offset argument to a long. - * See {@link #staticFieldOffset}. - */ - @Deprecated - public Object getObject(Object o, int offset) { - return getObject(o, (long)offset); - } - - /** - * @deprecated As of 1.4.1, cast the 32-bit offset argument to a long. - * See {@link #staticFieldOffset}. - */ - @Deprecated - public void putObject(Object o, int offset, Object x) { - putObject(o, (long)offset, x); - } - - /** - * @deprecated As of 1.4.1, cast the 32-bit offset argument to a long. - * See {@link #staticFieldOffset}. - */ - @Deprecated - public boolean getBoolean(Object o, int offset) { - return getBoolean(o, (long)offset); - } - - /** - * @deprecated As of 1.4.1, cast the 32-bit offset argument to a long. - * See {@link #staticFieldOffset}. - */ - @Deprecated - public void putBoolean(Object o, int offset, boolean x) { - putBoolean(o, (long)offset, x); - } - - /** - * @deprecated As of 1.4.1, cast the 32-bit offset argument to a long. - * See {@link #staticFieldOffset}. - */ - @Deprecated - public byte getByte(Object o, int offset) { - return getByte(o, (long)offset); - } - - /** - * @deprecated As of 1.4.1, cast the 32-bit offset argument to a long. - * See {@link #staticFieldOffset}. - */ - @Deprecated - public void putByte(Object o, int offset, byte x) { - putByte(o, (long)offset, x); - } - - /** - * @deprecated As of 1.4.1, cast the 32-bit offset argument to a long. - * See {@link #staticFieldOffset}. - */ - @Deprecated - public short getShort(Object o, int offset) { - return getShort(o, (long)offset); - } - - /** - * @deprecated As of 1.4.1, cast the 32-bit offset argument to a long. - * See {@link #staticFieldOffset}. - */ - @Deprecated - public void putShort(Object o, int offset, short x) { - putShort(o, (long)offset, x); - } - - /** - * @deprecated As of 1.4.1, cast the 32-bit offset argument to a long. - * See {@link #staticFieldOffset}. - */ - @Deprecated - public char getChar(Object o, int offset) { - return getChar(o, (long)offset); - } - - /** - * @deprecated As of 1.4.1, cast the 32-bit offset argument to a long. - * See {@link #staticFieldOffset}. - */ - @Deprecated - public void putChar(Object o, int offset, char x) { - putChar(o, (long)offset, x); - } - - /** - * @deprecated As of 1.4.1, cast the 32-bit offset argument to a long. - * See {@link #staticFieldOffset}. - */ - @Deprecated - public long getLong(Object o, int offset) { - return getLong(o, (long)offset); - } - - /** - * @deprecated As of 1.4.1, cast the 32-bit offset argument to a long. - * See {@link #staticFieldOffset}. - */ - @Deprecated - public void putLong(Object o, int offset, long x) { - putLong(o, (long)offset, x); - } - - /** - * @deprecated As of 1.4.1, cast the 32-bit offset argument to a long. - * See {@link #staticFieldOffset}. - */ - @Deprecated - public float getFloat(Object o, int offset) { - return getFloat(o, (long)offset); - } - - /** - * @deprecated As of 1.4.1, cast the 32-bit offset argument to a long. - * See {@link #staticFieldOffset}. - */ - @Deprecated - public void putFloat(Object o, int offset, float x) { - putFloat(o, (long)offset, x); - } - - /** - * @deprecated As of 1.4.1, cast the 32-bit offset argument to a long. - * See {@link #staticFieldOffset}. - */ - @Deprecated - public double getDouble(Object o, int offset) { - return getDouble(o, (long)offset); - } - - /** - * @deprecated As of 1.4.1, cast the 32-bit offset argument to a long. - * See {@link #staticFieldOffset}. - */ - @Deprecated - public void putDouble(Object o, int offset, double x) { - putDouble(o, (long)offset, x); - } - - // These work on values in the C heap. - - /** - * Fetches a value from a given memory address. If the address is zero, or - * does not point into a block obtained from {@link #allocateMemory}, the - * results are undefined. - * - * @see #allocateMemory - */ - public native byte getByte(long address); - - /** - * Stores a value into a given memory address. If the address is zero, or - * does not point into a block obtained from {@link #allocateMemory}, the - * results are undefined. - * - * @see #getByte(long) - */ - public native void putByte(long address, byte x); - - /** @see #getByte(long) */ - public native short getShort(long address); - /** @see #putByte(long, byte) */ - public native void putShort(long address, short x); - /** @see #getByte(long) */ - public native char getChar(long address); - /** @see #putByte(long, byte) */ - public native void putChar(long address, char x); - /** @see #getByte(long) */ - public native int getInt(long address); - /** @see #putByte(long, byte) */ - public native void putInt(long address, int x); - /** @see #getByte(long) */ - public native long getLong(long address); - /** @see #putByte(long, byte) */ - public native void putLong(long address, long x); - /** @see #getByte(long) */ - public native float getFloat(long address); - /** @see #putByte(long, byte) */ - public native void putFloat(long address, float x); - /** @see #getByte(long) */ - public native double getDouble(long address); - /** @see #putByte(long, byte) */ - public native void putDouble(long address, double x); - - /** - * Fetches a native pointer from a given memory address. If the address is - * zero, or does not point into a block obtained from {@link - * #allocateMemory}, the results are undefined. - * - * <p> If the native pointer is less than 64 bits wide, it is extended as - * an unsigned number to a Java long. The pointer may be indexed by any - * given byte offset, simply by adding that offset (as a simple integer) to - * the long representing the pointer. The number of bytes actually read - * from the target address maybe determined by consulting {@link - * #addressSize}. - * - * @see #allocateMemory - */ - public native long getAddress(long address); - - /** - * Stores a native pointer into a given memory address. If the address is - * zero, or does not point into a block obtained from {@link - * #allocateMemory}, the results are undefined. - * - * <p> The number of bytes actually written at the target address maybe - * determined by consulting {@link #addressSize}. - * - * @see #getAddress(long) - */ - public native void putAddress(long address, long x); - - /// wrappers for malloc, realloc, free: - - /** - * Allocates a new block of native memory, of the given size in bytes. The - * contents of the memory are uninitialized; they will generally be - * garbage. The resulting native pointer will never be zero, and will be - * aligned for all value types. Dispose of this memory by calling {@link - * #freeMemory}, or resize it with {@link #reallocateMemory}. - * - * @throws IllegalArgumentException if the size is negative or too large - * for the native size_t type - * - * @throws OutOfMemoryError if the allocation is refused by the system - * - * @see #getByte(long) - * @see #putByte(long, byte) - */ - public native long allocateMemory(long bytes); - - /** - * Resizes a new block of native memory, to the given size in bytes. The - * contents of the new block past the size of the old block are - * uninitialized; they will generally be garbage. The resulting native - * pointer will be zero if and only if the requested size is zero. The - * resulting native pointer will be aligned for all value types. Dispose - * of this memory by calling {@link #freeMemory}, or resize it with {@link - * #reallocateMemory}. The address passed to this method may be null, in - * which case an allocation will be performed. - * - * @throws IllegalArgumentException if the size is negative or too large - * for the native size_t type - * - * @throws OutOfMemoryError if the allocation is refused by the system - * - * @see #allocateMemory - */ - public native long reallocateMemory(long address, long bytes); - - /** - * Sets all bytes in a given block of memory to a fixed value - * (usually zero). - * - * <p>This method determines a block's base address by means of two parameters, - * and so it provides (in effect) a <em>double-register</em> addressing mode, - * as discussed in {@link #getInt(Object,long)}. When the object reference is null, - * the offset supplies an absolute base address. - * - * <p>The stores are in coherent (atomic) units of a size determined - * by the address and length parameters. If the effective address and - * length are all even modulo 8, the stores take place in 'long' units. - * If the effective address and length are (resp.) even modulo 4 or 2, - * the stores take place in units of 'int' or 'short'. - * - * @since 1.7 - */ - public native void setMemory(Object o, long offset, long bytes, byte value); - - /** - * Sets all bytes in a given block of memory to a fixed value - * (usually zero). This provides a <em>single-register</em> addressing mode, - * as discussed in {@link #getInt(Object,long)}. - * - * <p>Equivalent to <code>setMemory(null, address, bytes, value)</code>. - */ - public void setMemory(long address, long bytes, byte value) { - setMemory(null, address, bytes, value); - } - - /** - * Sets all bytes in a given block of memory to a copy of another - * block. - * - * <p>This method determines each block's base address by means of two parameters, - * and so it provides (in effect) a <em>double-register</em> addressing mode, - * as discussed in {@link #getInt(Object,long)}. When the object reference is null, - * the offset supplies an absolute base address. - * - * <p>The transfers are in coherent (atomic) units of a size determined - * by the address and length parameters. If the effective addresses and - * length are all even modulo 8, the transfer takes place in 'long' units. - * If the effective addresses and length are (resp.) even modulo 4 or 2, - * the transfer takes place in units of 'int' or 'short'. - * - * @since 1.7 - */ - public native void copyMemory(Object srcBase, long srcOffset, - Object destBase, long destOffset, - long bytes); - /** - * Sets all bytes in a given block of memory to a copy of another - * block. This provides a <em>single-register</em> addressing mode, - * as discussed in {@link #getInt(Object,long)}. - * - * Equivalent to <code>copyMemory(null, srcAddress, null, destAddress, bytes)</code>. - */ - public void copyMemory(long srcAddress, long destAddress, long bytes) { - copyMemory(null, srcAddress, null, destAddress, bytes); - } - - /** - * Disposes of a block of native memory, as obtained from {@link - * #allocateMemory} or {@link #reallocateMemory}. The address passed to - * this method may be null, in which case no action is taken. - * - * @see #allocateMemory - */ - public native void freeMemory(long address); - - /// random queries - - /** - * This constant differs from all results that will ever be returned from - * {@link #staticFieldOffset}, {@link #objectFieldOffset}, - * or {@link #arrayBaseOffset}. - */ - public static final int INVALID_FIELD_OFFSET = -1; - - /** - * Returns the offset of a field, truncated to 32 bits. - * This method is implemented as follows: - * <blockquote><pre> - * public int fieldOffset(Field f) { - * if (Modifier.isStatic(f.getModifiers())) - * return (int) staticFieldOffset(f); - * else - * return (int) objectFieldOffset(f); - * } - * </pre></blockquote> - * @deprecated As of 1.4.1, use {@link #staticFieldOffset} for static - * fields and {@link #objectFieldOffset} for non-static fields. - */ - @Deprecated - public int fieldOffset(Field f) { - if (Modifier.isStatic(f.getModifiers())) - return (int) staticFieldOffset(f); - else - return (int) objectFieldOffset(f); - } - - /** - * Returns the base address for accessing some static field - * in the given class. This method is implemented as follows: - * <blockquote><pre> - * public Object staticFieldBase(Class c) { - * Field[] fields = c.getDeclaredFields(); - * for (int i = 0; i < fields.length; i++) { - * if (Modifier.isStatic(fields[i].getModifiers())) { - * return staticFieldBase(fields[i]); - * } - * } - * return null; - * } - * </pre></blockquote> - * @deprecated As of 1.4.1, use {@link #staticFieldBase(Field)} - * to obtain the base pertaining to a specific {@link Field}. - * This method works only for JVMs which store all statics - * for a given class in one place. - */ - @Deprecated - public Object staticFieldBase(Class<?> c) { - Field[] fields = c.getDeclaredFields(); - for (int i = 0; i < fields.length; i++) { - if (Modifier.isStatic(fields[i].getModifiers())) { - return staticFieldBase(fields[i]); - } - } - return null; - } - - /** - * Report the location of a given field in the storage allocation of its - * class. Do not expect to perform any sort of arithmetic on this offset; - * it is just a cookie which is passed to the unsafe heap memory accessors. - * - * <p>Any given field will always have the same offset and base, and no - * two distinct fields of the same class will ever have the same offset - * and base. - * - * <p>As of 1.4.1, offsets for fields are represented as long values, - * although the Sun JVM does not use the most significant 32 bits. - * However, JVM implementations which store static fields at absolute - * addresses can use long offsets and null base pointers to express - * the field locations in a form usable by {@link #getInt(Object,long)}. - * Therefore, code which will be ported to such JVMs on 64-bit platforms - * must preserve all bits of static field offsets. - * @see #getInt(Object, long) - */ - public native long staticFieldOffset(Field f); - - /** - * Report the location of a given static field, in conjunction with {@link - * #staticFieldBase}. - * <p>Do not expect to perform any sort of arithmetic on this offset; - * it is just a cookie which is passed to the unsafe heap memory accessors. - * - * <p>Any given field will always have the same offset, and no two distinct - * fields of the same class will ever have the same offset. - * - * <p>As of 1.4.1, offsets for fields are represented as long values, - * although the Sun JVM does not use the most significant 32 bits. - * It is hard to imagine a JVM technology which needs more than - * a few bits to encode an offset within a non-array object, - * However, for consistency with other methods in this class, - * this method reports its result as a long value. - * @see #getInt(Object, long) - */ - public native long objectFieldOffset(Field f); - - /** - * Report the location of a given static field, in conjunction with {@link - * #staticFieldOffset}. - * <p>Fetch the base "Object", if any, with which static fields of the - * given class can be accessed via methods like {@link #getInt(Object, - * long)}. This value may be null. This value may refer to an object - * which is a "cookie", not guaranteed to be a real Object, and it should - * not be used in any way except as argument to the get and put routines in - * this class. - */ - public native Object staticFieldBase(Field f); - - /** - * Detect if the given class may need to be initialized. This is often - * needed in conjunction with obtaining the static field base of a - * class. - * @return false only if a call to {@code ensureClassInitialized} would have no effect - */ - public native boolean shouldBeInitialized(Class<?> c); - - /** - * Ensure the given class has been initialized. This is often - * needed in conjunction with obtaining the static field base of a - * class. - */ - public native void ensureClassInitialized(Class<?> c); - - /** - * Report the offset of the first element in the storage allocation of a - * given array class. If {@link #arrayIndexScale} returns a non-zero value - * for the same class, you may use that scale factor, together with this - * base offset, to form new offsets to access elements of arrays of the - * given class. - * - * @see #getInt(Object, long) - * @see #putInt(Object, long, int) - */ - public native int arrayBaseOffset(Class<?> arrayClass); - - /** The value of {@code arrayBaseOffset(boolean[].class)} */ - public static final int ARRAY_BOOLEAN_BASE_OFFSET - = theUnsafe.arrayBaseOffset(boolean[].class); - - /** The value of {@code arrayBaseOffset(byte[].class)} */ - public static final int ARRAY_BYTE_BASE_OFFSET - = theUnsafe.arrayBaseOffset(byte[].class); - - /** The value of {@code arrayBaseOffset(short[].class)} */ - public static final int ARRAY_SHORT_BASE_OFFSET - = theUnsafe.arrayBaseOffset(short[].class); - - /** The value of {@code arrayBaseOffset(char[].class)} */ - public static final int ARRAY_CHAR_BASE_OFFSET - = theUnsafe.arrayBaseOffset(char[].class); - - /** The value of {@code arrayBaseOffset(int[].class)} */ - public static final int ARRAY_INT_BASE_OFFSET - = theUnsafe.arrayBaseOffset(int[].class); - - /** The value of {@code arrayBaseOffset(long[].class)} */ - public static final int ARRAY_LONG_BASE_OFFSET - = theUnsafe.arrayBaseOffset(long[].class); - - /** The value of {@code arrayBaseOffset(float[].class)} */ - public static final int ARRAY_FLOAT_BASE_OFFSET - = theUnsafe.arrayBaseOffset(float[].class); - - /** The value of {@code arrayBaseOffset(double[].class)} */ - public static final int ARRAY_DOUBLE_BASE_OFFSET - = theUnsafe.arrayBaseOffset(double[].class); - - /** The value of {@code arrayBaseOffset(Object[].class)} */ - public static final int ARRAY_OBJECT_BASE_OFFSET - = theUnsafe.arrayBaseOffset(Object[].class); - - /** - * Report the scale factor for addressing elements in the storage - * allocation of a given array class. However, arrays of "narrow" types - * will generally not work properly with accessors like {@link - * #getByte(Object, int)}, so the scale factor for such classes is reported - * as zero. - * - * @see #arrayBaseOffset - * @see #getInt(Object, long) - * @see #putInt(Object, long, int) - */ - public native int arrayIndexScale(Class<?> arrayClass); - - /** The value of {@code arrayIndexScale(boolean[].class)} */ - public static final int ARRAY_BOOLEAN_INDEX_SCALE - = theUnsafe.arrayIndexScale(boolean[].class); - - /** The value of {@code arrayIndexScale(byte[].class)} */ - public static final int ARRAY_BYTE_INDEX_SCALE - = theUnsafe.arrayIndexScale(byte[].class); - - /** The value of {@code arrayIndexScale(short[].class)} */ - public static final int ARRAY_SHORT_INDEX_SCALE - = theUnsafe.arrayIndexScale(short[].class); - - /** The value of {@code arrayIndexScale(char[].class)} */ - public static final int ARRAY_CHAR_INDEX_SCALE - = theUnsafe.arrayIndexScale(char[].class); - - /** The value of {@code arrayIndexScale(int[].class)} */ - public static final int ARRAY_INT_INDEX_SCALE - = theUnsafe.arrayIndexScale(int[].class); - - /** The value of {@code arrayIndexScale(long[].class)} */ - public static final int ARRAY_LONG_INDEX_SCALE - = theUnsafe.arrayIndexScale(long[].class); - - /** The value of {@code arrayIndexScale(float[].class)} */ - public static final int ARRAY_FLOAT_INDEX_SCALE - = theUnsafe.arrayIndexScale(float[].class); - - /** The value of {@code arrayIndexScale(double[].class)} */ - public static final int ARRAY_DOUBLE_INDEX_SCALE - = theUnsafe.arrayIndexScale(double[].class); - - /** The value of {@code arrayIndexScale(Object[].class)} */ - public static final int ARRAY_OBJECT_INDEX_SCALE - = theUnsafe.arrayIndexScale(Object[].class); - - /** - * Report the size in bytes of a native pointer, as stored via {@link - * #putAddress}. This value will be either 4 or 8. Note that the sizes of - * other primitive types (as stored in native memory blocks) is determined - * fully by their information content. - */ - public native int addressSize(); - - /** The value of {@code addressSize()} */ - public static final int ADDRESS_SIZE = theUnsafe.addressSize(); - - /** - * Report the size in bytes of a native memory page (whatever that is). - * This value will always be a power of two. - */ - public native int pageSize(); - - - /// random trusted operations from JNI: - - /** - * Tell the VM to define a class, without security checks. By default, the - * class loader and protection domain come from the caller's class. - */ - public native Class<?> defineClass(String name, byte[] b, int off, int len, - ClassLoader loader, - ProtectionDomain protectionDomain); - - /** - * Define a class but do not make it known to the class loader or system dictionary. - * <p> - * For each CP entry, the corresponding CP patch must either be null or have - * the a format that matches its tag: - * <ul> - * <li>Integer, Long, Float, Double: the corresponding wrapper object type from java.lang - * <li>Utf8: a string (must have suitable syntax if used as signature or name) - * <li>Class: any java.lang.Class object - * <li>String: any object (not just a java.lang.String) - * <li>InterfaceMethodRef: (NYI) a method handle to invoke on that call site's arguments - * </ul> - * @params hostClass context for linkage, access control, protection domain, and class loader - * @params data bytes of a class file - * @params cpPatches where non-null entries exist, they replace corresponding CP entries in data - */ - public native Class<?> defineAnonymousClass(Class<?> hostClass, byte[] data, Object[] cpPatches); - - - /** Allocate an instance but do not run any constructor. - Initializes the class if it has not yet been. */ - public native Object allocateInstance(Class<?> cls) - throws InstantiationException; - - /** Lock the object. It must get unlocked via {@link #monitorExit}. */ - @Deprecated - public native void monitorEnter(Object o); - - /** - * Unlock the object. It must have been locked via {@link - * #monitorEnter}. - */ - @Deprecated - public native void monitorExit(Object o); - - /** - * Tries to lock the object. Returns true or false to indicate - * whether the lock succeeded. If it did, the object must be - * unlocked via {@link #monitorExit}. - */ - @Deprecated - public native boolean tryMonitorEnter(Object o); - - /** Throw the exception without telling the verifier. */ - public native void throwException(Throwable ee); - - - /** - * Atomically update Java variable to <tt>x</tt> if it is currently - * holding <tt>expected</tt>. - * @return <tt>true</tt> if successful - */ - public final native boolean compareAndSwapObject(Object o, long offset, - Object expected, - Object x); - - /** - * Atomically update Java variable to <tt>x</tt> if it is currently - * holding <tt>expected</tt>. - * @return <tt>true</tt> if successful - */ - public final native boolean compareAndSwapInt(Object o, long offset, - int expected, - int x); - - /** - * Atomically update Java variable to <tt>x</tt> if it is currently - * holding <tt>expected</tt>. - * @return <tt>true</tt> if successful - */ - public final native boolean compareAndSwapLong(Object o, long offset, - long expected, - long x); - - /** - * Fetches a reference value from a given Java variable, with volatile - * load semantics. Otherwise identical to {@link #getObject(Object, long)} - */ - public native Object getObjectVolatile(Object o, long offset); - - /** - * Stores a reference value into a given Java variable, with - * volatile store semantics. Otherwise identical to {@link #putObject(Object, long, Object)} - */ - public native void putObjectVolatile(Object o, long offset, Object x); - - /** Volatile version of {@link #getInt(Object, long)} */ - public native int getIntVolatile(Object o, long offset); - - /** Volatile version of {@link #putInt(Object, long, int)} */ - public native void putIntVolatile(Object o, long offset, int x); - - /** Volatile version of {@link #getBoolean(Object, long)} */ - public native boolean getBooleanVolatile(Object o, long offset); - - /** Volatile version of {@link #putBoolean(Object, long, boolean)} */ - public native void putBooleanVolatile(Object o, long offset, boolean x); - - /** Volatile version of {@link #getByte(Object, long)} */ - public native byte getByteVolatile(Object o, long offset); - - /** Volatile version of {@link #putByte(Object, long, byte)} */ - public native void putByteVolatile(Object o, long offset, byte x); - - /** Volatile version of {@link #getShort(Object, long)} */ - public native short getShortVolatile(Object o, long offset); - - /** Volatile version of {@link #putShort(Object, long, short)} */ - public native void putShortVolatile(Object o, long offset, short x); - - /** Volatile version of {@link #getChar(Object, long)} */ - public native char getCharVolatile(Object o, long offset); - - /** Volatile version of {@link #putChar(Object, long, char)} */ - public native void putCharVolatile(Object o, long offset, char x); - - /** Volatile version of {@link #getLong(Object, long)} */ - public native long getLongVolatile(Object o, long offset); - - /** Volatile version of {@link #putLong(Object, long, long)} */ - public native void putLongVolatile(Object o, long offset, long x); - - /** Volatile version of {@link #getFloat(Object, long)} */ - public native float getFloatVolatile(Object o, long offset); - - /** Volatile version of {@link #putFloat(Object, long, float)} */ - public native void putFloatVolatile(Object o, long offset, float x); - - /** Volatile version of {@link #getDouble(Object, long)} */ - public native double getDoubleVolatile(Object o, long offset); - - /** Volatile version of {@link #putDouble(Object, long, double)} */ - public native void putDoubleVolatile(Object o, long offset, double x); - - /** - * Version of {@link #putObjectVolatile(Object, long, Object)} - * that does not guarantee immediate visibility of the store to - * other threads. This method is generally only useful if the - * underlying field is a Java volatile (or if an array cell, one - * that is otherwise only accessed using volatile accesses). - */ - public native void putOrderedObject(Object o, long offset, Object x); - - /** Ordered/Lazy version of {@link #putIntVolatile(Object, long, int)} */ - public native void putOrderedInt(Object o, long offset, int x); - - /** Ordered/Lazy version of {@link #putLongVolatile(Object, long, long)} */ - public native void putOrderedLong(Object o, long offset, long x); - - /** - * Unblock the given thread blocked on <tt>park</tt>, or, if it is - * not blocked, cause the subsequent call to <tt>park</tt> not to - * block. Note: this operation is "unsafe" solely because the - * caller must somehow ensure that the thread has not been - * destroyed. Nothing special is usually required to ensure this - * when called from Java (in which there will ordinarily be a live - * reference to the thread) but this is not nearly-automatically - * so when calling from native code. - * @param thread the thread to unpark. - * - */ - public native void unpark(Object thread); - - /** - * Block current thread, returning when a balancing - * <tt>unpark</tt> occurs, or a balancing <tt>unpark</tt> has - * already occurred, or the thread is interrupted, or, if not - * absolute and time is not zero, the given time nanoseconds have - * elapsed, or if absolute, the given deadline in milliseconds - * since Epoch has passed, or spuriously (i.e., returning for no - * "reason"). Note: This operation is in the Unsafe class only - * because <tt>unpark</tt> is, so it would be strange to place it - * elsewhere. - */ - public native void park(boolean isAbsolute, long time); - - /** - * Gets the load average in the system run queue assigned - * to the available processors averaged over various periods of time. - * This method retrieves the given <tt>nelem</tt> samples and - * assigns to the elements of the given <tt>loadavg</tt> array. - * The system imposes a maximum of 3 samples, representing - * averages over the last 1, 5, and 15 minutes, respectively. - * - * @params loadavg an array of double of size nelems - * @params nelems the number of samples to be retrieved and - * must be 1 to 3. - * - * @return the number of samples actually retrieved; or -1 - * if the load average is unobtainable. - */ - public native int getLoadAverage(double[] loadavg, int nelems); - - // The following contain CAS-based Java implementations used on - // platforms not supporting native instructions - - /** - * Atomically adds the given value to the current value of a field - * or array element within the given object <code>o</code> - * at the given <code>offset</code>. - * - * @param o object/array to update the field/element in - * @param offset field/element offset - * @param delta the value to add - * @return the previous value - * @since 1.8 - */ - public final int getAndAddInt(Object o, long offset, int delta) { - int v; - do { - v = getIntVolatile(o, offset); - } while (!compareAndSwapInt(o, offset, v, v + delta)); - return v; - } - - /** - * Atomically adds the given value to the current value of a field - * or array element within the given object <code>o</code> - * at the given <code>offset</code>. - * - * @param o object/array to update the field/element in - * @param offset field/element offset - * @param delta the value to add - * @return the previous value - * @since 1.8 - */ - public final long getAndAddLong(Object o, long offset, long delta) { - long v; - do { - v = getLongVolatile(o, offset); - } while (!compareAndSwapLong(o, offset, v, v + delta)); - return v; - } - - /** - * Atomically exchanges the given value with the current value of - * a field or array element within the given object <code>o</code> - * at the given <code>offset</code>. - * - * @param o object/array to update the field/element in - * @param offset field/element offset - * @param newValue new value - * @return the previous value - * @since 1.8 - */ - public final int getAndSetInt(Object o, long offset, int newValue) { - int v; - do { - v = getIntVolatile(o, offset); - } while (!compareAndSwapInt(o, offset, v, newValue)); - return v; - } - - /** - * Atomically exchanges the given value with the current value of - * a field or array element within the given object <code>o</code> - * at the given <code>offset</code>. - * - * @param o object/array to update the field/element in - * @param offset field/element offset - * @param newValue new value - * @return the previous value - * @since 1.8 - */ - public final long getAndSetLong(Object o, long offset, long newValue) { - long v; - do { - v = getLongVolatile(o, offset); - } while (!compareAndSwapLong(o, offset, v, newValue)); - return v; - } - - /** - * Atomically exchanges the given reference value with the current - * reference value of a field or array element within the given - * object <code>o</code> at the given <code>offset</code>. - * - * @param o object/array to update the field/element in - * @param offset field/element offset - * @param newValue new value - * @return the previous value - * @since 1.8 - */ - public final Object getAndSetObject(Object o, long offset, Object newValue) { - Object v; - do { - v = getObjectVolatile(o, offset); - } while (!compareAndSwapObject(o, offset, v, newValue)); - return v; - } - - - /** - * Ensures lack of reordering of loads before the fence - * with loads or stores after the fence. - * @since 1.8 - */ - public native void loadFence(); - - /** - * Ensures lack of reordering of stores before the fence - * with loads or stores after the fence. - * @since 1.8 - */ - public native void storeFence(); - - /** - * Ensures lack of reordering of loads or stores before the fence - * with loads or stores after the fence. - * @since 1.8 - */ - public native void fullFence(); - - /** - * Throws IllegalAccessError; for use by the VM. - * @since 1.8 - */ - private static void throwIllegalAccessError() { - throw new IllegalAccessError(); - } - -} |