com.jstatcom.engine
Class CPtr

java.lang.Object
  com.jstatcom.engine.CPtr

Direct Known Subclasses:

CFunc, CMalloc

public class CPtr
extends java.lang.Object

An abstraction for a C pointer data type. A CPtr instance represents, on the Java side, a C pointer. The C pointer could be any type of C pointer. Methods such as copyIn,copyOut, getXXX, and setXXX, provide means to indirect the underlying C pointer.

Author:

Sheng Liang

See Also:

CFunc

Field Summary

static CPtr	NULL A canonical representation of C's NULL pointer.
static int	SIZE The size of a C pointer on the platform this Java virtual machine is running on.

Method Summary

void	copyIn(int bOff, byte[] buf, int index, int length) Indirect the C pointer, copying into memory pointed to by C pointer, from the specified array.
void	copyIn(int bOff, char[] buf, int index, int length) Indirect the C pointer, copying into memory pointed to by C pointer, from the specified array.
void	copyIn(int bOff, double[] buf, int index, int length) Indirect the C pointer, copying into memory pointed to by C pointer, from the specified array.
void	copyIn(int bOff, float[] buf, int index, int length) Indirect the C pointer, copying into memory pointed to by C pointer, from the specified array.
void	copyIn(int bOff, int[] buf, int index, int length) Indirect the C pointer, copying into memory pointed to by C pointer, from the specified array.
void	copyIn(int bOff, long[] buf, int index, int length) Indirect the C pointer, copying into memory pointed to by C pointer, from the specified array.
void	copyIn(int bOff, short[] buf, int index, int length) Indirect the C pointer, copying into memory pointed to by C pointer, from the specified array.
void	copyOut(int bOff, byte[] buf, int index, int length) Indirect the C pointer, copying from memory pointed to by C pointer, into the specified array.
void	copyOut(int bOff, char[] buf, int index, int length) Indirect the C pointer, copying from memory pointed to by C pointer, into the specified array.
void	copyOut(int bOff, double[] buf, int index, int length) Indirect the C pointer, copying from memory pointed to by C pointer, into the specified array.
void	copyOut(int bOff, float[] buf, int index, int length) Indirect the C pointer, copying from memory pointed to by C pointer, into the specified array.
void	copyOut(int bOff, int[] buf, int index, int length) Indirect the C pointer, copying from memory pointed to by C pointer, into the specified array.
void	copyOut(int bOff, long[] buf, int index, int length) Indirect the C pointer, copying from memory pointed to by C pointer, into the specified array.
void	copyOut(int bOff, short[] buf, int index, int length) Indirect the C pointer, copying from memory pointed to by C pointer, into the specified array.
boolean	equals(java.lang.Object other) Compares this CPtr to the specified object.
byte	getByte(int offset) Indirect the C pointer as a pointer to byte.
CPtr	getCPtr(int offset) Indirect the C pointer as a pointer to pointer.
double	getDouble(int offset) Indirect the C pointer as a pointer to double.
float	getFloat(int offset) Indirect the C pointer as a pointer to float.
int	getInt(int offset) Indirect the C pointer as a pointer to int.
long	getLong(int offset) Indirect the C pointer as a pointer to long.
short	getShort(int offset) Indirect the C pointer as a pointer to short.
java.lang.String	getString(int offset) Indirect the C pointer as a pointer to char *, a NULL -terminated C string.
int	hashCode() Returns a hashcode for the C pointer represented by this Cptr object.
void	setByte(int offset, byte value) Set value at location being pointed to.
void	setCPtr(int offset, CPtr value) Set value at location being pointed to.
void	setDouble(int offset, double value) Set value at location being pointed to.
void	setFloat(int offset, float value) Set value at location being pointed to.
void	setInt(int offset, int value) Set value at location being pointed to.
void	setLong(int offset, long value) Set value at location being pointed to.
void	setShort(int offset, short value) Set value at location being pointed to.
void	setString(int offset, java.lang.String value) Copy string value to the location being pointed to.

Methods inherited from class java.lang.Object

getClass, notify, notifyAll, toString, wait, wait, wait

Field Detail

SIZE

public static final int SIZE

The size of a C pointer on the platform this Java virtual machine is running on.

NULL

public static final CPtr NULL

A canonical representation of C's NULL pointer.

Method Detail

equals

public boolean equals(java.lang.Object other)

Compares this CPtr to the specified object.

Overrides:

equals in class java.lang.Object

Parameters:

other - a CPtr

Returns:

true if the class of this CPtr object and the class of other are exactly equal, and the C pointers being pointed to by these objects are also equal. Returns false otherwise.

hashCode

public int hashCode()

Returns a hashcode for the C pointer represented by this Cptr object.

Overrides:

hashCode in class java.lang.Object

Returns:

a hash code value for the represented C pointer.

copyIn

public void copyIn(int bOff,
                   byte[] buf,
                   int index,
                   int length)

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

Parameters:

bOff - 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

copyIn

public void copyIn(int bOff,
                   short[] buf,
                   int index,
                   int length)

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

Parameters:

bOff - 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

copyIn

public void copyIn(int bOff,
                   char[] buf,
                   int index,
                   int length)

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

Parameters:

bOff - 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

copyIn

public void copyIn(int bOff,
                   int[] buf,
                   int index,
                   int length)

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

Parameters:

bOff - 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

copyIn

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

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

Parameters:

bOff - 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

copyIn

public void copyIn(int bOff,
                   float[] buf,
                   int index,
                   int length)

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

Parameters:

bOff - 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

copyIn

public void copyIn(int bOff,
                   double[] buf,
                   int index,
                   int length)

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

Parameters:

bOff - 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

copyOut

public void copyOut(int bOff,
                    byte[] buf,
                    int index,
                    int length)

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

Parameters:

bOff - byte offset from pointer into which data is copied

buf - byte array into which data is copied

index - array index from which to start copying

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

copyOut

public void copyOut(int bOff,
                    short[] buf,
                    int index,
                    int length)

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

Parameters:

bOff - 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 C pointer that must be copied

copyOut

public void copyOut(int bOff,
                    char[] buf,
                    int index,
                    int length)

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

Parameters:

bOff - 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 C pointer that must be copied

copyOut

public void copyOut(int bOff,
                    int[] buf,
                    int index,
                    int length)

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

Parameters:

bOff - 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 C pointer that must be copied

copyOut

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

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

Parameters:

bOff - 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 C pointer that must be copied

copyOut

public void copyOut(int bOff,
                    float[] buf,
                    int index,
                    int length)

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

Parameters:

bOff - 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 C pointer that must be copied

copyOut

public void copyOut(int bOff,
                    double[] buf,
                    int index,
                    int length)

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

Parameters:

bOff - 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 C pointer that must be copied

getByte

public byte getByte(int offset)

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

Parameters:

offset - offset from pointer to perform the indirection

Returns:

the byte value being pointed to

getShort

public short getShort(int offset)

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

Parameters:

offset - byte offset from pointer to perform the indirection

Returns:

the short value being pointed to

getInt

public int getInt(int offset)

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

Parameters:

offset - byte offset from pointer to perform the indirection

Returns:

the int value being pointed to

getLong

public long getLong(int offset)

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

Parameters:

offset - byte offset from pointer to perform the indirection

Returns:

the long value being pointed to

getFloat

public float getFloat(int offset)

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

Parameters:

offset - byte offset from pointer to perform the indirection

Returns:

the float value being pointed to

getDouble

public double getDouble(int offset)

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

Parameters:

offset - byte offset from pointer to perform the indirection

Returns:

the double value being pointed to

getCPtr

public CPtr getCPtr(int offset)

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

Parameters:

offset - byte offset from pointer to perform the indirection

Returns:

the pointer value being pointed to

getString

public java.lang.String getString(int offset)

Indirect the C pointer as a pointer to char *, a NULL -terminated C string. Convert the C string to a String.

Parameters:

offset - byte offset from pointer to obtain the C string

Returns:

the String value being pointed to

setByte

public void setByte(int offset,
                    byte value)

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

Parameters:

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

value - byte value to set

setShort

public void setShort(int offset,
                     short value)

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

Parameters:

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

value - short value to set

setInt

public void setInt(int offset,
                   int value)

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

Parameters:

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

value - int value to set

setLong

public void setLong(int offset,
                    long value)

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

Parameters:

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

value - long value to set

setFloat

public void setFloat(int offset,
                     float value)

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

Parameters:

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

value - float value to set

setDouble

public void setDouble(int offset,
                      double value)

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

Parameters:

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

value - double value to set

setCPtr

public void setCPtr(int offset,
                    CPtr value)

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

Parameters:

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

value - CPtr value to set

setString

public void setString(int offset,
                      java.lang.String value)

Copy string value to the location being pointed to. Copy each element in value, converted to native encoding, at an offset from the location pointed to by this pointer.

Parameters:

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

value - String value to set