Package com.sun.jna

Klasse Pointer

java.lang.Object

com.sun.jna.Pointer

Bekannte direkte Unterklassen:

Function, Memory

public class Pointer
extends Object

An abstraction for a native pointer data type. A Pointer instance represents, on the Java side, a native pointer. The native pointer could be any type of native pointer. Methods such as write, read, getXXX, and setXXX, provide means to access memory underlying the native pointer.

While a constructor exists to create a Pointer from an integer value, it's not generally a good idea to be creating pointers that way.

Autor:

Sheng Liang, originator, Todd Fast, suitability modifications, Timothy Wall, robust library loading

Siehe auch:

• Function

Feldübersicht

Felder

Modifizierer und Typ	Feld	Beschreibung
static final Pointer	NULL	Convenience constant, same as null.
protected long	peer	Pointer value of the real native pointer.

Konstruktorübersicht

Konstruktoren

Konstruktor	Beschreibung
Pointer()	Derived class must assign peer pointer value.
Pointer(long peer)	Create from native pointer.

Methodenübersicht

Modifizierer und Typ	Methode	Beschreibung
void	clear(long size)	Zero memory for the given number of bytes.
static final Pointer	createConstant(int peer)	Convenience constant, equivalent to (void*)CONSTANT.
static final Pointer	createConstant(long peer)	Convenience constant, equivalent to (void*)CONSTANT.
String	dump(long offset, int size)	Dump memory for debugging purposes.
boolean	equals(Object o)
byte	getByte(long offset)	Indirect the native pointer as a pointer to byte.
byte[]	getByteArray(long offset, int arraySize)	Read a native array of bytes of size arraySize from the given offset from this Pointer.
ByteBuffer	getByteBuffer(long offset, long length)	Get a ByteBuffer mapped to the memory pointed to by the pointer, ensuring the buffer uses native byte order.
char	getChar(long offset)	Indirect the native pointer as a pointer to wchar_t.
char[]	getCharArray(long offset, int arraySize)	Read a native array of wchar_t of size arraySize from the given offset from this Pointer.
double	getDouble(long offset)	Indirect the native pointer as a pointer to double.
double[]	getDoubleArray(long offset, int arraySize)	Read a native array of double of size arraySize from the given offset from this Pointer.
float	getFloat(long offset)	Indirect the native pointer as a pointer to float.
float[]	getFloatArray(long offset, int arraySize)	Read a native array of float of size arraySize from the given offset from this Pointer.
int	getInt(long offset)	Indirect the native pointer as a pointer to int.
int[]	getIntArray(long offset, int arraySize)	Read a native array of int32 of size arraySize from the given offset from this Pointer.
long	getLong(long offset)	Indirect the native pointer as a pointer to long.
long[]	getLongArray(long offset, int arraySize)	Read a native array of int64 of size arraySize from the given offset from this Pointer.
NativeLong	getNativeLong(long offset)	Indirect the native pointer as a pointer to long.
Pointer	getPointer(long offset)	Indirect the native pointer as a pointer to pointer.
Pointer[]	getPointerArray(long offset)	Returns an array of Pointer.
Pointer[]	getPointerArray(long offset, int arraySize)	Returns an array of Pointer of the requested size.
short	getShort(long offset)	Indirect the native pointer as a pointer to short.
short[]	getShortArray(long offset, int arraySize)	Read a native array of int16 of size arraySize from the given offset from this Pointer.
String	getString(long offset)	Copy native memory to a Java String.
String	getString(long offset, String encoding)	Copy native memory to a Java String using the requested encoding.
String[]	getStringArray(long offset)	Returns an array of String based on a native array of char *.
String[]	getStringArray(long offset, int length)	Returns an array of String based on a native array of char *, using the given array length.
String[]	getStringArray(long offset, int length, String encoding)	Returns an array of String based on a native array of char* or wchar_t* based on the wide parameter, using the given array length.
String[]	getStringArray(long offset, String encoding)	Returns an array of String based on a native array of char *, using the requested encoding.
(Package privat) Object	getValue(long offset, Class<?> type, Object currentValue)
String	getWideString(long offset)	Read a wide (const wchar_t *) string from memory.
String[]	getWideStringArray(long offset)
String[]	getWideStringArray(long offset, int length)
int	hashCode()
long	indexOf(long offset, byte value)	Returns the offset of the given value in memory from the given offset, or -1 if the value is not found.
static long	nativeValue(Pointer p)	Read the native peer value.
static void	nativeValue(Pointer p, long value)	Set the native peer value.
void	read(long offset, byte[] buf, int index, int length)	Indirect the native pointer, copying from memory pointed to by native pointer, into the specified array.
void	read(long offset, char[] buf, int index, int length)	Indirect the native pointer, copying from memory pointed to by native pointer, into the specified array.
void	read(long offset, double[] buf, int index, int length)	Indirect the native pointer, copying from memory pointed to by native pointer, into the specified array.
void	read(long offset, float[] buf, int index, int length)	Indirect the native pointer, copying from memory pointed to by native pointer, into the specified array.
void	read(long offset, int[] buf, int index, int length)	Indirect the native pointer, copying from memory pointed to by native pointer, into the specified array.
void	read(long offset, long[] buf, int index, int length)	Indirect the native pointer, copying from memory pointed to by native pointer, into the specified array.
void	read(long offset, short[] buf, int index, int length)	Indirect the native pointer, copying from memory pointed to by native pointer, into the specified array.
void	read(long offset, Pointer[] buf, int index, int length)	Indirect the native pointer, copying from memory pointed to by native pointer, into the specified array.
void	setByte(long offset, byte value)	Set value at location being pointed to.
void	setChar(long offset, char value)	Set value at location being pointed to.
void	setDouble(long offset, double value)	Set value at location being pointed to.
void	setFloat(long offset, float value)	Set value at location being pointed to.
void	setInt(long offset, int value)	Set value at location being pointed to.
void	setLong(long offset, long value)	Set value at location being pointed to.
void	setMemory(long offset, long length, byte value)	Write value to the requested bank of memory.
void	setNativeLong(long offset, NativeLong value)	Set value at location being pointed to.
void	setPointer(long offset, Pointer value)	Set value at location being pointed to.
void	setShort(long offset, short value)	Set value at location being pointed to.
void	setString(long offset, WString value)	Copy string value to the location being pointed to as a wide string (wchar_t*).
void	setString(long offset, String value)	Copy bytes out of string value to the location being pointed to, using the encoding indicated by Native.getDefaultStringEncoding().
void	setString(long offset, String value, String encoding)	Copy string value to the location being pointed to, using the requested encoding.
(Package privat) void	setValue(long offset, Object value, Class<?> type)
void	setWideString(long offset, String value)	Copy string value to the location being pointed to as a wide string (wchar_t*).
Pointer	share(long offset)	Provide a view of this memory using the given offset to calculate a new base address.
Pointer	share(long offset, long sz)	Provide a view of this memory using the given offset to calculate a new base address, bounds-limiting the memory with the given size.
String	toString()
void	write(long offset, byte[] buf, int index, int length)	Indirect the native pointer, copying into memory pointed to by native pointer, from the specified array.
void	write(long offset, char[] buf, int index, int length)	Indirect the native pointer, copying into memory pointed to by native pointer, from the specified array.
void	write(long offset, double[] buf, int index, int length)	Indirect the native pointer, copying into memory pointed to by native pointer, from the specified array.
void	write(long offset, float[] buf, int index, int length)	Indirect the native pointer, copying into memory pointed to by native pointer, from the specified array.
void	write(long offset, int[] buf, int index, int length)	Indirect the native pointer, copying into memory pointed to by native pointer, from the specified array.
void	write(long offset, long[] buf, int index, int length)	Indirect the native pointer, copying into memory pointed to by native pointer, from the specified array.
void	write(long offset, short[] buf, int index, int length)	Indirect the native pointer, copying into memory pointed to by native pointer, from the specified array.
void	write(long bOff, Pointer[] buf, int index, int length)	Write the given array of Pointer to native memory.

Von Klasse geerbte Methoden java.lang.Object

clone, finalize, getClass, notify, notifyAll, wait, wait, wait

Felddetails

NULL

public static final Pointer NULL

Convenience constant, same as null.

peer

protected long peer

Pointer value of the real native pointer. Use long to be 64-bit safe.

Konstruktordetails

Pointer

Pointer()

Derived class must assign peer pointer value.

Pointer

public Pointer(long peer)

Create from native pointer. Don't use this unless you know what you're doing.

Methodendetails

createConstant

public static final Pointer createConstant(long peer)

Convenience constant, equivalent to (void*)CONSTANT.

createConstant

public static final Pointer createConstant(int peer)

Convenience constant, equivalent to (void*)CONSTANT. This version will avoid setting any of the high bits on 64-bit systems.

share

public Pointer share(long offset)

Provide a view of this memory using the given offset to calculate a new base address.

share

public Pointer share(long offset,
 long sz)

Provide a view of this memory using the given offset to calculate a new base address, bounds-limiting the memory with the given size.

clear

public void clear(long size)

Zero memory for the given number of bytes.

equals

public boolean equals(Object o)

Setzt außer Kraft:

equals in Klasse Object

hashCode

public int hashCode()

Setzt außer Kraft:

hashCode in Klasse Object

indexOf

public long indexOf(long offset,
 byte value)

Returns the offset of the given value in memory from the given offset, or -1 if the value is not found.

read

public void read(long offset,
 byte[] buf,
 int index,
 int length)

Indirect the native pointer, copying from memory pointed to by native pointer, into the specified array.

Parameter:

offset - byte offset from pointer from which data is copied

buf - byte array into which data is copied

index - array index to which data is copied

length - number of elements from native pointer that must be copied

read

public void read(long offset,
 short[] buf,
 int index,
 int length)

Indirect the native pointer, copying from memory pointed to by native pointer, into the specified array.

Parameter:

offset - byte offset from pointer from which data is copied

buf - short array into which data is copied

index - array index to which data is copied

length - number of elements from native pointer that must be copied

read

public void read(long offset,
 char[] buf,
 int index,
 int length)

Indirect the native pointer, copying from memory pointed to by native pointer, into the specified array.

Parameter:

offset - byte offset from pointer from which data is copied

buf - char array into which data is copied

index - array index to which data is copied

length - number of elements from native pointer that must be copied

read

public void read(long offset,
 int[] buf,
 int index,
 int length)

Indirect the native pointer, copying from memory pointed to by native pointer, into the specified array.

Parameter:

offset - byte offset from pointer from which data is copied

buf - int array into which data is copied

index - array index to which data is copied

length - number of elements from native pointer that must be copied

read

public void read(long offset,
 long[] buf,
 int index,
 int length)

Indirect the native pointer, copying from memory pointed to by native pointer, into the specified array.

Parameter:

offset - byte offset from pointer from which data is copied

buf - long array into which data is copied

index - array index to which data is copied

length - number of elements from native pointer that must be copied

read

public void read(long offset,
 float[] buf,
 int index,
 int length)

Indirect the native pointer, copying from memory pointed to by native pointer, into the specified array.

Parameter:

offset - byte offset from pointer from which data is copied

buf - float array into which data is copied

index - array index to which data is copied

length - number of elements from native pointer that must be copied

read

public void read(long offset,
 double[] buf,
 int index,
 int length)

Indirect the native pointer, copying from memory pointed to by native pointer, into the specified array.

Parameter:

offset - byte offset from pointer from which data is copied

buf - double array into which data is copied

index - array index to which data is copied

length - number of elements from native pointer that must be copied

read

public void read(long offset,
 Pointer[] buf,
 int index,
 int length)

Indirect the native pointer, copying from memory pointed to by native pointer, into the specified array.

Parameter:

offset - byte offset from pointer from which data is copied

buf - Pointer array into which data is copied

index - array index to which data is copied

length - number of elements from native pointer that must be copied

write

public void write(long offset,
 byte[] buf,
 int index,
 int length)

Indirect the native pointer, copying into memory pointed to by native pointer, from the specified array.

Parameter:

offset - byte offset from pointer into which data is copied

buf - byte array from which to copy

index - array index from which to start copying

length - number of elements from buf that must be copied

write

public void write(long offset,
 short[] buf,
 int index,
 int length)

Indirect the native pointer, copying into memory pointed to by native pointer, from the specified array.

Parameter:

offset - byte offset from pointer into which data is copied

buf - short array from which to copy

index - array index from which to start copying

length - number of elements from buf that must be copied

write

public void write(long offset,
 char[] buf,
 int index,
 int length)

Indirect the native pointer, copying into memory pointed to by native pointer, from the specified array.

Parameter:

offset - byte offset from pointer into which data is copied

buf - char array from which to copy

index - array index from which to start copying

length - number of elements from buf that must be copied

write

public void write(long offset,
 int[] buf,
 int index,
 int length)

Indirect the native pointer, copying into memory pointed to by native pointer, from the specified array.

Parameter:

offset - byte offset from pointer into which data is copied

buf - int array from which to copy

index - array index from which to start copying

length - number of elements from buf that must be copied

write

public void write(long offset,
 long[] buf,
 int index,
 int length)

Indirect the native pointer, copying into memory pointed to by native pointer, from the specified array.

Parameter:

offset - byte offset from pointer into which data is copied

buf - long array from which to copy

index - array index from which to start copying

length - number of elements from buf that must be copied

write

public void write(long offset,
 float[] buf,
 int index,
 int length)

Indirect the native pointer, copying into memory pointed to by native pointer, from the specified array.

Parameter:

offset - byte offset from pointer into which data is copied

buf - float array from which to copy

index - array index from which to start copying

length - number of elements from buf that must be copied

write

public void write(long offset,
 double[] buf,
 int index,
 int length)

Indirect the native pointer, copying into memory pointed to by native pointer, from the specified array.

Parameter:

offset - byte offset from pointer into which data is copied

buf - double array from which to copy

index - array index from which to start copying

length - number of elements from buf that must be copied

write

public void write(long bOff,
 Pointer[] buf,
 int index,
 int length)

Write the given array of Pointer to native memory.

Parameter:

bOff - byte offset from pointer into which data is copied

buf - Pointer array from which to copy

index - array index from which to start copying

length - number of elements from buf that must be copied

getValue

Object getValue(long offset,
 Class<?> type,
 Object currentValue)

getByte

public byte getByte(long offset)

Indirect the native pointer as a pointer to byte. This is equivalent to the expression *((jbyte *)((char *)Pointer + offset)).

Parameter:

offset - offset from pointer to perform the indirection

Gibt zurück:

the byte value being pointed to

getChar

public char getChar(long offset)

Indirect the native pointer as a pointer to wchar_t. This is equivalent to the expression *((wchar_t*)((char *)Pointer + offset)).

Parameter:

offset - offset from pointer to perform the indirection

Gibt zurück:

the wchar_t value being pointed to

getShort

public short getShort(long offset)

Indirect the native pointer as a pointer to short. This is equivalent to the expression *((jshort *)((char *)Pointer + offset)).

Parameter:

offset - byte offset from pointer to perform the indirection

Gibt zurück:

the short value being pointed to

getInt

public int getInt(long offset)

Indirect the native pointer as a pointer to int. This is equivalent to the expression *((jint *)((char *)Pointer + offset)).

Parameter:

offset - byte offset from pointer to perform the indirection

Gibt zurück:

the int value being pointed to

getLong

public long getLong(long offset)

Indirect the native pointer as a pointer to long. This is equivalent to the expression *((jlong *)((char *)Pointer + offset)).

Parameter:

offset - byte offset from pointer to perform the indirection

Gibt zurück:

the long value being pointed to

getNativeLong

public NativeLong getNativeLong(long offset)

Indirect the native pointer as a pointer to long. This is equivalent to the expression *((long *)((char *)Pointer + offset)).

Parameter:

offset - byte offset from pointer to perform the indirection

Gibt zurück:

the long value being pointed to

getFloat

public float getFloat(long offset)

Indirect the native pointer as a pointer to float. This is equivalent to the expression *((jfloat *)((char *)Pointer + offset)).

Parameter:

offset - byte offset from pointer to perform the indirection

Gibt zurück:

the float value being pointed to

getDouble

public double getDouble(long offset)

Indirect the native pointer as a pointer to double. This is equivalent to the expression *((jdouble *)((char *)Pointer + offset)).

Parameter:

offset - byte offset from pointer to perform the indirection

Gibt zurück:

the double value being pointed to

getPointer

public Pointer getPointer(long offset)

Indirect the native pointer as a pointer to pointer. This is equivalent to the expression *((void **)((char *)Pointer + offset)).

Parameter:

offset - byte offset from pointer to perform the indirection

Gibt zurück:

a Pointer equivalent of the pointer value being pointed to, or null if the pointer value is NULL;

getByteBuffer

public ByteBuffer getByteBuffer(long offset,
 long length)

Get a ByteBuffer mapped to the memory pointed to by the pointer, ensuring the buffer uses native byte order.

Parameter:

offset - byte offset from pointer to start the buffer

length - Length of ByteBuffer

Gibt zurück:

a direct ByteBuffer that accesses the memory being pointed to,

getWideString

public String getWideString(long offset)

Read a wide (const wchar_t *) string from memory.

getString

public String getString(long offset)

Copy native memory to a Java String. The encoding used is obtained form Native.getDefaultStringEncoding().

Parameter:

offset - byte offset from pointer to start reading bytes

Gibt zurück:

the String value being pointed to

getString

public String getString(long offset,
 String encoding)

Copy native memory to a Java String using the requested encoding.

Parameter:

offset - byte offset from pointer to obtain the native string

encoding - the desired encoding

Gibt zurück:

the String value being pointed to

getByteArray

public byte[] getByteArray(long offset,
 int arraySize)

Read a native array of bytes of size arraySize from the given offset from this Pointer.

getCharArray

public char[] getCharArray(long offset,
 int arraySize)

Read a native array of wchar_t of size arraySize from the given offset from this Pointer.

getShortArray

public short[] getShortArray(long offset,
 int arraySize)

Read a native array of int16 of size arraySize from the given offset from this Pointer.

getIntArray

public int[] getIntArray(long offset,
 int arraySize)

Read a native array of int32 of size arraySize from the given offset from this Pointer.

getLongArray

public long[] getLongArray(long offset,
 int arraySize)

Read a native array of int64 of size arraySize from the given offset from this Pointer.

getFloatArray

public float[] getFloatArray(long offset,
 int arraySize)

Read a native array of float of size arraySize from the given offset from this Pointer.

getDoubleArray

public double[] getDoubleArray(long offset,
 int arraySize)

Read a native array of double of size arraySize from the given offset from this Pointer.

getPointerArray

public Pointer[] getPointerArray(long offset)

Returns an array of Pointer. The array length is determined by a NULL-valued terminating element.

getPointerArray

public Pointer[] getPointerArray(long offset,
 int arraySize)

Returns an array of Pointer of the requested size.

getStringArray

public String[] getStringArray(long offset)

Returns an array of String based on a native array of char *. The array length is determined by a NULL-valued terminating element.

The strings are decoded using the encoding returned by Native.getDefaultStringEncoding().

getStringArray

public String[] getStringArray(long offset,
 String encoding)

Returns an array of String based on a native array of char *, using the requested encoding. The array length is determined by a NULL-valued terminating element.

getStringArray

public String[] getStringArray(long offset,
 int length)

Returns an array of String based on a native array of char *, using the given array length.

The strings are decoded using the encoding returned by Native.getDefaultStringEncoding().

getWideStringArray

public String[] getWideStringArray(long offset)

getWideStringArray

public String[] getWideStringArray(long offset,
 int length)

getStringArray

public String[] getStringArray(long offset,
 int length,
 String encoding)

Returns an array of String based on a native array of char* or wchar_t* based on the wide parameter, using the given array length.

Parameter:

offset -

length -

encoding -

setValue

void setValue(long offset,
 Object value,
 Class<?> type)

setMemory

public void setMemory(long offset,
 long length,
 byte value)

Write value to the requested bank of memory.

Parameter:

offset - byte offset from pointer to start

length - number of bytes to write

value - value to be written

setByte

public void setByte(long offset,
 byte value)

Set value at location being pointed to. This is equivalent to the expression *((jbyte *)((char *)Pointer + offset)) = value.

Parameter:

offset - byte offset from pointer at which value must be set

value - byte value to set

setShort

public void setShort(long offset,
 short value)

Set value at location being pointed to. This is equivalent to the expression *((jshort *)((char *)Pointer + offset)) = value.

Parameter:

offset - byte offset from pointer at which value must be set

value - short value to set

setChar

public void setChar(long offset,
 char value)

Set value at location being pointed to. This is equivalent to the expression *((wchar_t *)((char *)Pointer + offset)) = value.

Parameter:

offset - byte offset from pointer at which value must be set

value - char value to set

setInt

public void setInt(long offset,
 int value)

Set value at location being pointed to. This is equivalent to the expression *((jint *)((char *)Pointer + offset)) = value.

Parameter:

offset - byte offset from pointer at which value must be set

value - int value to set

setLong

public void setLong(long offset,
 long value)

Set value at location being pointed to. This is equivalent to the expression *((jlong *)((char *)Pointer + offset)) = value.

Parameter:

offset - byte offset from pointer at which value must be set

value - long value to set

setNativeLong

public void setNativeLong(long offset,
 NativeLong value)

Set value at location being pointed to. This is equivalent to the expression *((long *)((char *)Pointer + offset)) = value.

Parameter:

offset - byte offset from pointer at which value must be set

value - long value to set

setFloat

public void setFloat(long offset,
 float value)

Set value at location being pointed to. This is equivalent to the expression *((jfloat *)((char *)Pointer + offset)) = value.

Parameter:

offset - byte offset from pointer at which value must be set

value - float value to set

setDouble

public void setDouble(long offset,
 double value)

Set value at location being pointed to. This is equivalent to the expression *((jdouble *)((char *)Pointer + offset)) = value.

Parameter:

offset - byte offset from pointer at which value must be set

value - double value to set

setPointer

public void setPointer(long offset,
 Pointer value)

Set value at location being pointed to. This is equivalent to the expression *((void **)((char *)Pointer + offset)) = value.

Parameter:

offset - byte offset from pointer at which value must be set

value - Pointer holding the actual pointer value to set, which may be null to indicate a NULL pointer.

setWideString

public void setWideString(long offset,
 String value)

Copy string value to the location being pointed to as a wide string (wchar_t*).

Parameter:

offset - byte offset from pointer at which characters in value must be set

value - java.lang.String value to set

setString

public void setString(long offset,
 WString value)

Copy string value to the location being pointed to as a wide string (wchar_t*).

Parameter:

offset - byte offset from pointer at which characters in value must be set

value - WString value to set

setString

public void setString(long offset,
 String value)

Copy bytes out of string value to the location being pointed to, using the encoding indicated by Native.getDefaultStringEncoding().

Parameter:

offset - byte offset from pointer at which characters in value must be set

value - java.lang.String value to set

setString

public void setString(long offset,
 String value,
 String encoding)

Copy string value to the location being pointed to, using the requested encoding.

Parameter:

offset - byte offset from pointer at which characters in value must be set

value - java.lang.String value to set

encoding - desired encoding

dump

public String dump(long offset,
 int size)

Dump memory for debugging purposes.

toString

public String toString()

Setzt außer Kraft:

toString in Klasse Object

nativeValue

public static long nativeValue(Pointer p)

Read the native peer value. Use with caution.

nativeValue

public static void nativeValue(Pointer p,
 long value)

Set the native peer value. Use with caution.