Package com.kenai.jffi

Class UnsafeMemoryIO

java.lang.Object
com.kenai.jffi.MemoryIO
com.kenai.jffi.UnsafeMemoryIO
public abstract class UnsafeMemoryIO
extends MemoryIO
An implementation of MemoryIO using sun.misc.Unsafe

  • Field Summary

    Fields
    Modifier and Type Field Description
    protected static sun.misc.Unsafe unsafe  

  • Constructor Summary

    Constructors
    Constructor Description
    UnsafeMemoryIO()  

  • Method Summary

    Modifier and Type Method Description
    void _copyMemory​(long src, long dst, long size)  
    byte getByte​(long address)
    Reads an 8 bit integer from a native memory location.
    void getByteArray​(long address, byte[] data, int offset, int length)
    Reads a java byte array from native memory.
    void getCharArray​(long address, char[] data, int offset, int length)
    Reads a java char array from native memory.
    double getDouble​(long address)
    Reads a 64 bit floating point value from a native memory location.
    void getDoubleArray​(long address, double[] data, int offset, int length)
    Reads a java double array from native memory.
    float getFloat​(long address)
    Reads a 32 bit floating point value from a native memory location.
    void getFloatArray​(long address, float[] data, int offset, int length)
    Reads a java float array from native memory.
    int getInt​(long address)
    Reads a 32 bit integer from a native memory location.
    void getIntArray​(long address, int[] data, int offset, int length)
    Reads a java int array from native memory.
    long getLong​(long address)
    Reads a 64 bit integer from a native memory location.
    void getLongArray​(long address, long[] data, int offset, int length)
    Reads a java long array from native memory.
    short getShort​(long address)
    Reads a 16 bit integer from a native memory location.
    void getShortArray​(long address, short[] data, int offset, int length)
    Reads a java short array from native memory.
    long getStringLength​(long address)
    Gets the length of a native ascii or utf-8 string.
    byte[] getZeroTerminatedByteArray​(long address)
    Reads a byte array from native memory, stopping when a zero byte is found.
    byte[] getZeroTerminatedByteArray​(long address, int maxlen)
    Reads a byte array from native memory, stopping when a zero byte is found, or the maximum length is reached.
    long memchr​(long address, int value, long size)
    Gets the address of a byte value in a native memory region.
    void memcpy​(long dst, long src, long size)
    Copies bytes from one memory location to another.
    void memmove​(long dst, long src, long size)
    Copies potentially overlapping memory areas.
    void putByte​(long address, byte value)
    Writes an 8 bit integer value to a native memory location.
    void putByteArray​(long address, byte[] data, int offset, int length)
    Writes a java byte array to native memory.
    void putCharArray​(long address, char[] data, int offset, int length)
    Writes a java char array to native memory.
    void putDouble​(long address, double value)
    Writes a 64 bit floating point value to a native memory location.
    void putDoubleArray​(long address, double[] data, int offset, int length)
    Writes a java double array to native memory.
    void putFloat​(long address, float value)
    Writes a 32 bit floating point value to a native memory location.
    void putFloatArray​(long address, float[] data, int offset, int length)
    Writes a java double array to native memory.
    void putInt​(long address, int value)
    Writes a 32 bit integer value to a native memory location.
    void putIntArray​(long address, int[] data, int offset, int length)
    Writes a java int array to native memory.
    void putLong​(long address, long value)
    Writes a 64 bit integer value to a native memory location.
    void putLongArray​(long address, long[] data, int offset, int length)
    Writes a java long array to native memory.
    void putShort​(long address, short value)
    Writes a 16 bit integer value to a native memory location.
    void putShortArray​(long address, short[] data, int offset, int length)
    Writes a java short array to native memory.
    void putZeroTerminatedByteArray​(long address, byte[] data, int offset, int length)
    Copies a java byte array to native memory and appends a NUL terminating byte.
    void setMemory​(long src, long size, byte value)
    Sets a region of native memory to a specific byte value.

    Methods inherited from class com.kenai.jffi.MemoryIO

    allocateMemory, copyMemory, freeMemory, getAddress, getCheckedInstance, getDirectBufferAddress, getInstance, getZeroTerminatedByteArray, indexOf, indexOf, memset, newDirectByteBuffer, putAddress

    Methods inherited from class java.lang.Object

    clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

  • Field Details

    • unsafe

      protected static sun.misc.Unsafe unsafe

  • Constructor Details

    • UnsafeMemoryIO

      public UnsafeMemoryIO()

  • Method Details

    • getByte

      public final byte getByte​(long address)
      Description copied from class: MemoryIO
      Reads an 8 bit integer from a native memory location.
      Specified by:
      getByte in class MemoryIO
      Parameters:
      address - The memory location to get the value from.
      Returns:
      A byte containing the value.

    • getShort

      public final short getShort​(long address)
      Description copied from class: MemoryIO
      Reads a 16 bit integer from a native memory location.
      Specified by:
      getShort in class MemoryIO
      Parameters:
      address - The memory location to get the value from.
      Returns:
      A short containing the value.

    • getInt

      public final int getInt​(long address)
      Description copied from class: MemoryIO
      Reads a 32 bit integer from a native memory location.
      Specified by:
      getInt in class MemoryIO
      Parameters:
      address - The memory location to get the value from.
      Returns:
      An int containing the value.

    • getLong

      public final long getLong​(long address)
      Description copied from class: MemoryIO
      Reads a 64 bit integer from a native memory location.
      Specified by:
      getLong in class MemoryIO
      Parameters:
      address - The memory location to get the value from.
      Returns:
      A long containing the value.

    • getFloat

      public final float getFloat​(long address)
      Description copied from class: MemoryIO
      Reads a 32 bit floating point value from a native memory location.
      Specified by:
      getFloat in class MemoryIO
      Parameters:
      address - The memory location to get the value from.
      Returns:
      A float containing the value.

    • getDouble

      public final double getDouble​(long address)
      Description copied from class: MemoryIO
      Reads a 64 bit floating point value from a native memory location.
      Specified by:
      getDouble in class MemoryIO
      Parameters:
      address - The memory location to get the value from.
      Returns:
      A double containing the value.

    • putByte

      public final void putByte​(long address, byte value)
      Description copied from class: MemoryIO
      Writes an 8 bit integer value to a native memory location.
      Specified by:
      putByte in class MemoryIO
      Parameters:
      address - The memory location to put the value.
      value - The value to write to memory.

    • putShort

      public final void putShort​(long address, short value)
      Description copied from class: MemoryIO
      Writes a 16 bit integer value to a native memory location.
      Specified by:
      putShort in class MemoryIO
      Parameters:
      address - The memory location to put the value.
      value - The value to write to memory.

    • putInt

      public final void putInt​(long address, int value)
      Description copied from class: MemoryIO
      Writes a 32 bit integer value to a native memory location.
      Specified by:
      putInt in class MemoryIO
      Parameters:
      address - The memory location to put the value.
      value - The value to write to memory.

    • putLong

      public final void putLong​(long address, long value)
      Description copied from class: MemoryIO
      Writes a 64 bit integer value to a native memory location.
      Specified by:
      putLong in class MemoryIO
      Parameters:
      address - The memory location to put the value.
      value - The value to write to memory.

    • putFloat

      public final void putFloat​(long address, float value)
      Description copied from class: MemoryIO
      Writes a 32 bit floating point value to a native memory location.
      Specified by:
      putFloat in class MemoryIO
      Parameters:
      address - The memory location to put the value.
      value - The value to write to memory.

    • putDouble

      public final void putDouble​(long address, double value)
      Description copied from class: MemoryIO
      Writes a 64 bit floating point value to a native memory location.
      Specified by:
      putDouble in class MemoryIO
      Parameters:
      address - The memory location to put the value.
      value - The value to write to memory.

    • _copyMemory

      public final void _copyMemory​(long src, long dst, long size)

    • setMemory

      public final void setMemory​(long src, long size, byte value)
      Description copied from class: MemoryIO
      Sets a region of native memory to a specific byte value.
      Specified by:
      setMemory in class MemoryIO
      Parameters:
      src - The address of start of the native memory.
      size - The number of bytes to set.
      value - The value to set the native memory to.

    • memcpy

      public final void memcpy​(long dst, long src, long size)
      Description copied from class: MemoryIO
      Copies bytes from one memory location to another. The memory areas
      Specified by:
      memcpy in class MemoryIO
      Parameters:
      dst - The destination memory address.
      src - The source memory address.
      size - The number of bytes to copy.

    • memmove

      public final void memmove​(long dst, long src, long size)
      Description copied from class: MemoryIO
      Copies potentially overlapping memory areas.
      Specified by:
      memmove in class MemoryIO
      Parameters:
      dst - The destination memory address.
      src - The source memory address.
      size - The number of bytes to copy.

    • memchr

      public final long memchr​(long address, int value, long size)
      Description copied from class: MemoryIO
      Gets the address of a byte value in a native memory region.
      Specified by:
      memchr in class MemoryIO
      Parameters:
      address - The native memory address to start searching.
      value - The value to search for.
      size - The size of the native memory region being searched.
      Returns:
      The address of the value, or 0 (zero) if not found.

    • putByteArray

      public final void putByteArray​(long address, byte[] data, int offset, int length)
      Description copied from class: MemoryIO
      Writes a java byte array to native memory.
      Specified by:
      putByteArray in class MemoryIO
      Parameters:
      address - The native memory address to copy the array to.
      data - The java array to copy.
      offset - The offset within the array to start copying from.
      length - The number of array elements to copy.

    • getByteArray

      public final void getByteArray​(long address, byte[] data, int offset, int length)
      Description copied from class: MemoryIO
      Reads a java byte array from native memory.
      Specified by:
      getByteArray in class MemoryIO
      Parameters:
      address - The native memory address to copy the array from.
      data - The java array to copy.
      offset - The offset within the array to start copying to.
      length - The number of array elements to copy.

    • putCharArray

      public final void putCharArray​(long address, char[] data, int offset, int length)
      Description copied from class: MemoryIO
      Writes a java char array to native memory.
      Specified by:
      putCharArray in class MemoryIO
      Parameters:
      address - The native memory address to copy the array to.
      data - The java array to copy.
      offset - The offset within the array to start copying from.
      length - The number of array elements to copy.

    • getCharArray

      public final void getCharArray​(long address, char[] data, int offset, int length)
      Description copied from class: MemoryIO
      Reads a java char array from native memory.
      Specified by:
      getCharArray in class MemoryIO
      Parameters:
      address - The native memory address to copy the array from.
      data - The java array to copy.
      offset - The offset within the array to start copying to.
      length - The number of array elements to copy.

    • putShortArray

      public final void putShortArray​(long address, short[] data, int offset, int length)
      Description copied from class: MemoryIO
      Writes a java short array to native memory.
      Specified by:
      putShortArray in class MemoryIO
      Parameters:
      address - The native memory address to copy the array to.
      data - The java array to copy.
      offset - The offset within the array to start copying from.
      length - The number of array elements to copy.

    • getShortArray

      public final void getShortArray​(long address, short[] data, int offset, int length)
      Description copied from class: MemoryIO
      Reads a java short array from native memory.
      Specified by:
      getShortArray in class MemoryIO
      Parameters:
      address - The native memory address to copy the array from.
      data - The java array to copy.
      offset - The offset within the array to start copying to.
      length - The number of array elements to copy.

    • putIntArray

      public final void putIntArray​(long address, int[] data, int offset, int length)
      Description copied from class: MemoryIO
      Writes a java int array to native memory.
      Specified by:
      putIntArray in class MemoryIO
      Parameters:
      address - The native memory address to copy the array to.
      data - The java array to copy.
      offset - The offset within the array to start copying from.
      length - The number of array elements to copy.

    • getIntArray

      public final void getIntArray​(long address, int[] data, int offset, int length)
      Description copied from class: MemoryIO
      Reads a java int array from native memory.
      Specified by:
      getIntArray in class MemoryIO
      Parameters:
      address - The native memory address to copy the array from.
      data - The java array to copy.
      offset - The offset within the array to start copying to.
      length - The number of array elements to copy.

    • putLongArray

      public final void putLongArray​(long address, long[] data, int offset, int length)
      Description copied from class: MemoryIO
      Writes a java long array to native memory.
      Specified by:
      putLongArray in class MemoryIO
      Parameters:
      address - The native memory address to copy the array to.
      data - The java array to copy.
      offset - The offset within the array to start copying from.
      length - The number of array elements to copy.

    • getLongArray

      public final void getLongArray​(long address, long[] data, int offset, int length)
      Description copied from class: MemoryIO
      Reads a java long array from native memory.
      Specified by:
      getLongArray in class MemoryIO
      Parameters:
      address - The native memory address to copy the array from.
      data - The java array to copy.
      offset - The offset within the array to start copying to.
      length - The number of array elements to copy.

    • putFloatArray

      public final void putFloatArray​(long address, float[] data, int offset, int length)
      Description copied from class: MemoryIO
      Writes a java double array to native memory.
      Specified by:
      putFloatArray in class MemoryIO
      Parameters:
      address - The native memory address to copy the array to.
      data - The java array to copy.
      offset - The offset within the array to start copying from.
      length - The number of array elements to copy.

    • getFloatArray

      public final void getFloatArray​(long address, float[] data, int offset, int length)
      Description copied from class: MemoryIO
      Reads a java float array from native memory.
      Specified by:
      getFloatArray in class MemoryIO
      Parameters:
      address - The native memory address to copy the array from.
      data - The java array to copy.
      offset - The offset within the array to start copying to.
      length - The number of array elements to copy.

    • putDoubleArray

      public final void putDoubleArray​(long address, double[] data, int offset, int length)
      Description copied from class: MemoryIO
      Writes a java double array to native memory.
      Specified by:
      putDoubleArray in class MemoryIO
      Parameters:
      address - The native memory address to copy the array to.
      data - The java array to copy.
      offset - The offset within the array to start copying from.
      length - The number of array elements to copy.

    • getDoubleArray

      public final void getDoubleArray​(long address, double[] data, int offset, int length)
      Description copied from class: MemoryIO
      Reads a java double array from native memory.
      Specified by:
      getDoubleArray in class MemoryIO
      Parameters:
      address - The native memory address to copy the array from.
      data - The java array to copy.
      offset - The offset within the array to start copying to.
      length - The number of array elements to copy.

    • getStringLength

      public final long getStringLength​(long address)
      Description copied from class: MemoryIO
      Gets the length of a native ascii or utf-8 string.
      Specified by:
      getStringLength in class MemoryIO
      Parameters:
      address - The native address of the string.
      Returns:
      The length of the string, in bytes.

    • getZeroTerminatedByteArray

      public final byte[] getZeroTerminatedByteArray​(long address)
      Description copied from class: MemoryIO
      Reads a byte array from native memory, stopping when a zero byte is found. This can be used to read ascii or utf-8 strings from native memory.
      Specified by:
      getZeroTerminatedByteArray in class MemoryIO
      Parameters:
      address - The address to read the data from.
      Returns:
      The byte array containing a copy of the native data. Any zero byte is stripped from the end.

    • getZeroTerminatedByteArray

      public final byte[] getZeroTerminatedByteArray​(long address, int maxlen)
      Description copied from class: MemoryIO
      Reads a byte array from native memory, stopping when a zero byte is found, or the maximum length is reached. This can be used to read ascii or utf-8 strings from native memory.
      Specified by:
      getZeroTerminatedByteArray in class MemoryIO
      Parameters:
      address - The address to read the data from.
      maxlen - The limit of the memory area to scan for a zero byte.
      Returns:
      The byte array containing a copy of the native data. Any zero byte is stripped from the end.

    • putZeroTerminatedByteArray

      public final void putZeroTerminatedByteArray​(long address, byte[] data, int offset, int length)
      Description copied from class: MemoryIO
      Copies a java byte array to native memory and appends a NUL terminating byte. Note A total of length + 1 bytes is written to native memory.
      Specified by:
      putZeroTerminatedByteArray in class MemoryIO
      Parameters:
      address - The address to copy to.
      data - The byte array to copy to native memory
      offset - The offset within the byte array to begin copying from
      length - The number of bytes to copy to native memory