com.jniwrapper
Class Parameter

java.lang.Object
  com.jniwrapper.Parameter

Direct Known Subclasses:

AbstractFloat, AnsiStringArray, Callback, Char, DelegatingParameter, Int16, Int32, Int64, Int8, Pointer, Pointer.Void, PrimitiveArray, Str, StringArray, Structure, UInt16, UInt32, UInt8, Union, WideStringArray, ZeroTerminatedString

public abstract class Parameter
extends java.lang.Object

Common parent class for all types of function parameters.

Field Summary

protected static java.lang.String	LICENSE_TYPE
protected static java.lang.String	V

Constructor Summary

Parameter(DataBuffer dataBuffer, int offset)
Constructs a new Parameter object that is initially stored in a given buffer at a given offset.

Method Summary

protected void	acceptIOPerformer(IOPerformer performer, DataBuffer buffer, int initialOffset, boolean isReadOperation, boolean invokedByCallback) Implementation of a Visitor pattern for parameter IO.
protected Parameter	asReturnValue() Returns a parameter that represents this one as a return value.
abstract java.lang.Object	clone()
protected void	dataBufferAssigned() Called when new parameter data buffer assigned.
boolean	equals(java.lang.Object obj) Compares this Parameter object to a given object.
protected int	getAlignedLength() Returns a parameter length in bytes aligned to default alignment.
int	getAlignmentRequirement()
protected DataBuffer	getDataBuffer() Returns a current data storage.
protected int	getDataBufferOffset() Returns a current offset within data storage.
abstract java.lang.String	getDebugInfo() Return debug info for JNIWrapper parameter.
abstract int	getLength() Returns the length of the parameter in memory.
int	hashCode()
protected static java.lang.String	indent(java.lang.String param, int size) Utility method used for readable output in toString().
void	pop(DataBuffer stackBuffer, int offset, boolean invokedByCallback) Default implementation that does nothing because most primitive types do nothing on pop.
void	push(DataBuffer stackBuffer, int offset, boolean invokedByCallback) Writes a parameter to a function stacks.
void	read(byte[] arr, int offset) Reads the parameter value from a byte array.
void	read(byte[] arr, int offset, boolean invokedByCallback) Reads the parameter value from a byte array.
abstract void	read(DataBuffer stackBuffer, int offset, boolean invokedByCallback) Reads this parameter from a specified data source.
protected void	setDataBuffer(DataBuffer newBuffer, int newOffset, boolean shouldRead) Sets the data buffer this parameter should use to store data and an offset in bytes within that buffer.
static byte[]	toByteArray(Parameter param) Converts a parameter to a byte array.
void	write(byte[] arr, int offset) Writes the parameter value to a byte array.
abstract void	write(DataBuffer stackBuffer, int offset, boolean invokedByCallback) Writes this parameter to a specified data source.

Methods inherited from class java.lang.Object

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

Field Detail

V

protected static final java.lang.String V

See Also:

Constant Field Values

LICENSE_TYPE

protected static final java.lang.String LICENSE_TYPE

Constructor Detail

Parameter

public Parameter(DataBuffer dataBuffer,
                 int offset)

Constructs a new Parameter object that is initially stored in a given buffer at a given offset.

Parameters:

dataBuffer - initial data buffer where this parameter should be stored.

offset - offset in the given data buffer where this parameter should be stored.

Method Detail

dataBufferAssigned

protected void dataBufferAssigned()

Called when new parameter data buffer assigned.

getLength

public abstract int getLength()

Returns the length of the parameter in memory. This method is similar to C sizeof() operator.

write

public abstract void write(DataBuffer stackBuffer,
                           int offset,
                           boolean invokedByCallback)
                    throws MemoryAccessViolationException

Writes this parameter to a specified data source.

Throws:

MemoryAccessViolationException

read

public abstract void read(DataBuffer stackBuffer,
                          int offset,
                          boolean invokedByCallback)
                   throws MemoryAccessViolationException

Reads this parameter from a specified data source.

Throws:

MemoryAccessViolationException

setDataBuffer

protected void setDataBuffer(DataBuffer newBuffer,
                             int newOffset,
                             boolean shouldRead)

Sets the data buffer this parameter should use to store data and an offset in bytes within that buffer.

getDataBuffer

protected DataBuffer getDataBuffer()

Returns a current data storage.

getDataBufferOffset

protected int getDataBufferOffset()

Returns a current offset within data storage.

equals

public boolean equals(java.lang.Object obj)

Compares this Parameter object to a given object. Two Parameter objects are considered equal if their byte representations are equal and they are of the same type. Subclasses may override this method as appropriate.

Overrides:

equals in class java.lang.Object

Parameters:

obj - a value to compare this object to.

Returns:

true if two objects are equal.

hashCode

public int hashCode()

Overrides:

hashCode in class java.lang.Object

clone

public abstract java.lang.Object clone()

Overrides:

clone in class java.lang.Object

getAlignedLength

protected int getAlignedLength()

Returns a parameter length in bytes aligned to default alignment.

getAlignmentRequirement

public int getAlignmentRequirement()

Returns:

required alignment within a structure or an array

push

public void push(DataBuffer stackBuffer,
                 int offset,
                 boolean invokedByCallback)
          throws MemoryAccessViolationException

Writes a parameter to a function stacks.

Throws:

MemoryAccessViolationException

pop

public void pop(DataBuffer stackBuffer,
                int offset,
                boolean invokedByCallback)
         throws MemoryAccessViolationException

Default implementation that does nothing because most primitive types do nothing on pop. Reads a parameter from a function stack.

Throws:

MemoryAccessViolationException

asReturnValue

protected Parameter asReturnValue()

Returns a parameter that represents this one as a return value. Implementors may use this as a convenience shortcut for users when implementing such objects as strings or arrays to allow users to specify an object as a return value instead of requiring a pointer to it. For general use the default implementation should suffice.

Returns:

this

acceptIOPerformer

protected void acceptIOPerformer(IOPerformer performer,
                                 DataBuffer buffer,
                                 int initialOffset,
                                 boolean isReadOperation,
                                 boolean invokedByCallback)

Implementation of a Visitor pattern for parameter IO. A performer is responsible for reading and writing the parameter. Users implementing a complex parameter from scratch (i.e. not by extending a pre-existing class such as Structure or Pointer) may wish to override this method to make a performer visit object internal parts.

Parameters:

performer - a visitor responsible for I/Oing the parameter.

buffer - data buffer for I/O operation.

initialOffset - I/O operation offset of this parameter in the buffer.

write

public void write(byte[] arr,
                  int offset)

Writes the parameter value to a byte array.

read

public void read(byte[] arr,
                 int offset)

Reads the parameter value from a byte array.

read

public void read(byte[] arr,
                 int offset,
                 boolean invokedByCallback)

Reads the parameter value from a byte array.

toByteArray

public static byte[] toByteArray(Parameter param)

Converts a parameter to a byte array. Constructs a byte array and writes a specified parameter to the array.

indent

protected static java.lang.String indent(java.lang.String param,
                                         int size)

Utility method used for readable output in toString(). Adds an indentation at the start of each line into paramater. Lines are identified by "\n" character.

getDebugInfo

public abstract java.lang.String getDebugInfo()

Return debug info for JNIWrapper parameter.

Returns:

debug info