Java Reference类代码示例

import com.sun.max.vm.reference.Reference; //导入依赖的package包/类
/**
 * 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
 */
@SUBSTITUTE(optional = true)
public void copyMemory(Object srcBase, long srcOffset,
                              Object destBase, long destOffset,
                              long bytes) {
    Pointer src;
    if (srcBase == null) {
        src = Pointer.fromLong(srcOffset);
    } else {
        src = Reference.fromJava(srcBase).toOrigin().plus(srcOffset);
    }
    Pointer dest;
    if (destBase == null) {
        dest = Pointer.fromLong(destOffset);
    } else {
        dest = Reference.fromJava(destBase).toOrigin().plus(destOffset);
    }
    Memory.copyBytes(src, dest, Size.fromLong(bytes));
}
 

import com.sun.max.vm.reference.Reference; //导入依赖的package包/类
/**
 * Note: Must be kept in sync with the original JDK source.
 */
@SUBSTITUTE
boolean enqueue(java.lang.ref.Reference r) {
    synchronized (r) {
        JLRRAlias rAlias = asJLRRAlias(r);
        if (rAlias.queue == ENQUEUED) {
            return false;
        }
        synchronized (lock) {
            rAlias.queue = ENQUEUED;
            rAlias.next = (head == null) ? r : head;
            head = r;
            queueLength++;
            if (ClassRegistry.JLR_FINAL_REFERENCE.isInstance(r)) {
                sun.misc.VM.addFinalRefCount(1);
            }
            lock.notifyAll();
            if (SpecialReferenceManager.specialReferenceLogger.enabled()) {
                SpecialReferenceManager.specialReferenceLogger.logEnqueue(ObjectAccess.readClassActor(r), Reference.fromJava(r).toOrigin(), Reference.fromJava(this).toOrigin());
            }
            return true;
        }
    }
}
 

import com.sun.max.vm.reference.Reference; //导入依赖的package包/类
/**
 * Reads an int field from the specified offset of the specified object.
 * @see sun.misc.Unsafe#getInt(Object, long)
 * @param object the object
 * @param offset the offset from the beginning of the object
 * @return the value at the specified offset
 */
@SUBSTITUTE
public int getInt(Object object, long offset) {
    if (object == null) {
        return Pointer.fromLong(offset).readInt(0);
    }
    return Reference.fromJava(object).readInt(Offset.fromLong(offset));
}
 

import com.sun.max.vm.reference.Reference; //导入依赖的package包/类
/**
 * Writes an int into the object at the specified offset.
 * @see sun.misc.Unsafe#putInt(Object, long, int)
 * @param object the object
 * @param offset the offset from the beginning of the object
 * @param value the value to write at the specified offset
 */
@SUBSTITUTE
public void putInt(Object object, long offset, int value) {
    if (object == null) {
        Pointer.fromLong(offset).writeInt(0, value);
    }
    Reference.fromJava(object).writeInt(Offset.fromLong(offset), value);
}
 

import com.sun.max.vm.reference.Reference; //导入依赖的package包/类
/**
 * Writes an object reference into the object at the specified offset.
 * @see sun.misc.Unsafe#putObject(Object, long, Object)
 * @param object the object
 * @param offset the offset from the beginning of the object
 * @param value the value to write at the specified offset
 */
@SUBSTITUTE
public void putObject(Object object, long offset, Object value) {
    if (object == null) {
        Pointer.fromLong(offset).writeReference(0, Reference.fromJava(value));
    }
    Reference.fromJava(object).writeReference(Offset.fromLong(offset), Reference.fromJava(value));
}
 

import com.sun.max.vm.reference.Reference; //导入依赖的package包/类
/**
 * Reads a boolean field from the specified offset of the specified object.
 * @see sun.misc.Unsafe#getBoolean(Object, long)
 * @param object the object
 * @param offset the offset from the beginning of the object
 * @return the value at the specified offset
 */
@SUBSTITUTE
public boolean getBoolean(Object object, long offset) {
    if (object == null) {
        return Pointer.fromLong(offset).readBoolean(0);
    }
    return Reference.fromJava(object).readBoolean(Offset.fromLong(offset));
}
 

import com.sun.max.vm.reference.Reference; //导入依赖的package包/类
/**
 * Writes a boolean into the object at the specified offset.
 * @see sun.misc.Unsafe#putBoolean(Object, long, boolean)
 * @param object the object
 * @param offset the offset from the beginning of the object
 * @param value the value to write at the specified offset
 */
@SUBSTITUTE
public void putBoolean(Object object, long offset, boolean value) {
    if (object == null) {
        Pointer.fromLong(offset).writeBoolean(0, value);
    }
    Reference.fromJava(object).writeBoolean(Offset.fromLong(offset), value);
}
 

import com.sun.max.vm.reference.Reference; //导入依赖的package包/类
/**
 * Reads a byte field from the specified offset of the specified object.
 * @see sun.misc.Unsafe#getByte(Object, long)
 * @param object the object
 * @param offset the offset from the beginning of the object
 * @return the value at the specified offset
 */
@SUBSTITUTE
public byte getByte(Object object, long offset) {
    if (object == null) {
        return Pointer.fromLong(offset).readByte(0);
    }
    return Reference.fromJava(object).readByte(Offset.fromLong(offset));
}
 

import com.sun.max.vm.reference.Reference; //导入依赖的package包/类
/**
 * Writes a byte into the object at the specified offset.
 * @see sun.misc.Unsafe#putByte(Object, long, byte)
 * @param object the object
 * @param offset the offset from the beginning of the object
 * @param value the value to write at the specified offset
 */
@SUBSTITUTE
public void putByte(Object object, long offset, byte value) {
    if (object == null) {
        Pointer.fromLong(offset).writeByte(0, value);
    }
    Reference.fromJava(object).writeByte(Offset.fromLong(offset), value);
}
 

import com.sun.max.vm.reference.Reference; //导入依赖的package包/类
@INLINE
public Reference compareAndSwapReference(Reference ref, Offset offset, Reference expectedValue, Reference newValue) {
    heapScheme().preWriteBarrier(ref, offset, newValue);
    final Reference result = toOrigin(ref).compareAndSwapReference(offset, expectedValue, newValue);
    heapScheme().postWriteBarrier(ref, offset, newValue);
    return result;
}
 

import com.sun.max.vm.reference.Reference; //导入依赖的package包/类
/**
 * Writes a short into the object at the specified offset.
 * @see sun.misc.Unsafe#putShort(Object, long, short)
 * @param object the object
 * @param offset the offset from the beginning of the object
 * @param value the value to write at the specified offset
 */
@SUBSTITUTE
public void putShort(Object object, long offset, short value) {
    if (object == null) {
        Pointer.fromLong(offset).writeShort(0, value);
    }
    Reference.fromJava(object).writeShort(Offset.fromLong(offset), value);
}
 

import com.sun.max.vm.reference.Reference; //导入依赖的package包/类
/**
 * Reads a char field from the specified offset of the specified object.
 * @see sun.misc.Unsafe#getChar(Object, long)
 * @param object the object
 * @param offset the offset from the beginning of the object
 * @return the value at the specified offset
 */
@SUBSTITUTE
public char getChar(Object object, long offset) {
    if (object == null) {
        return Pointer.fromLong(offset).readChar(0);
    }
    return Reference.fromJava(object).readChar(Offset.fromLong(offset));
}
 

import com.sun.max.vm.reference.Reference; //导入依赖的package包/类
/**
 * Writes a char into the object at the specified offset.
 * @see sun.misc.Unsafe#putChar(Object, long, char)
 * @param object the object
 * @param offset the offset from the beginning of the object
 * @param value the value to write at the specified offset
 */
@SUBSTITUTE
public void putChar(Object object, long offset, char value) {
    if (object == null) {
        Pointer.fromLong(offset).writeChar(0, value);
    }
    Reference.fromJava(object).writeChar(Offset.fromLong(offset), value);
}
 

import com.sun.max.vm.reference.Reference; //导入依赖的package包/类
/**
 * Reads a long field from the specified offset of the specified object.
 * @see sun.misc.Unsafe#getLong(Object, long)
 * @param object the object
 * @param offset the offset from the beginning of the object
 * @return the value at the specified offset
 */
@SUBSTITUTE
public long getLong(Object object, long offset) {
    if (object == null) {
        return Pointer.fromLong(offset).readLong(0);
    }
    return Reference.fromJava(object).readLong(Offset.fromLong(offset));
}
 

import com.sun.max.vm.reference.Reference; //导入依赖的package包/类
/**
 * Writes a long into the object at the specified offset.
 * @see sun.misc.Unsafe#putLong(Object, long, long)
 * @param object the object
 * @param offset the offset from the beginning of the object
 * @param value the value to write at the specified offset
 */
@SUBSTITUTE
public void putLong(Object object, long offset, long value) {
    if (object == null) {
        Pointer.fromLong(offset).writeLong(0, value);
    }
    Reference.fromJava(object).writeLong(Offset.fromLong(offset), value);
}