com.ghgande.j2mod.modbus.msg

Class ReadCoilsRequest

java.lang.Object

com.ghgande.j2mod.modbus.msg.ModbusMessageImpl

com.ghgande.j2mod.modbus.msg.ModbusRequest

com.ghgande.j2mod.modbus.msg.ReadCoilsRequest

All Implemented Interfaces:

ModbusMessage

public class ReadCoilsRequest
extends ModbusRequest

Class implementing a ReadCoilsRequest. The implementation directly correlates with the class 1 function read coils (FC 1). It encapsulates the corresponding request message.

Coils are understood as bits that can be manipulated (i.e. set or unset).

Version:

2.0 (March 2016)

Author:

Dieter Wimberger, jfhaugh, Steve O'Hara (4NG)

Constructor Summary

Constructors

Constructor and Description
ReadCoilsRequest() Constructs a new ReadCoilsRequest instance.
ReadCoilsRequest(int ref, int count) Constructs a new ReadCoilsRequest instance with a given reference and count of coils (i.e.

Method Summary

Modifier and Type	Method and Description
ModbusResponse	createResponse(AbstractModbusListener listener) Returns the ModbusResponse that represents the answer to this ModbusRequest.
int	getBitCount() Returns the number of bits (i.e.
byte[]	getMessage() Returns the raw message as an array of bytes.
int	getReference() Returns the reference of the register to to start reading from with this ReadCoilsRequest.
ModbusResponse	getResponse() Returns the ModbusResponse that correlates with this ModbusRequest.
void	readData(DataInput din) Reads the subclass specific data from the given DataInput instance.
void	setBitCount(int count) Sets the number of bits (i.e.
void	setReference(int ref) Sets the reference of the register to start reading from with this ReadCoilsRequest.
void	writeData(DataOutput dout) Writes the subclass specific data to the given DataOutput.

Methods inherited from class com.ghgande.j2mod.modbus.msg.ModbusRequest

createExceptionResponse, createModbusRequest

Methods inherited from class com.ghgande.j2mod.modbus.msg.ModbusMessageImpl

getDataLength, getFunctionCode, getHexMessage, getOutputLength, getProtocolID, getTransactionID, getUnitID, isHeadless, readFrom, setDataLength, setHeadless, setHeadless, setProtocolID, setTransactionID, setUnitID, writeTo

Methods inherited from class java.lang.Object

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

Constructor Detail

ReadCoilsRequest

public ReadCoilsRequest()

Constructs a new ReadCoilsRequest instance.

ReadCoilsRequest

public ReadCoilsRequest(int ref,
                        int count)

Constructs a new ReadCoilsRequest instance with a given reference and count of coils (i.e. bits) to be read.

Parameters:

ref - the reference number of the register to read from.

count - the number of bits to be read.

Method Detail

getResponse

public ModbusResponse getResponse()

Description copied from class: ModbusRequest

Returns the ModbusResponse that correlates with this ModbusRequest.

The response must include the unit number, function code, as well as any transport-specific header information.

This method is used to create an empty response which must be populated by the caller. It is commonly used to un-marshal responses from Modbus slaves.

Specified by:

getResponse in class ModbusRequest

Returns:

the corresponding ModbusResponse.

createResponse

public ModbusResponse createResponse(AbstractModbusListener listener)

Description copied from class: ModbusRequest

Returns the ModbusResponse that represents the answer to this ModbusRequest.

The implementation should take care about assembling the reply to this ModbusRequest.

This method is used to create responses from the process image associated with the listener. It is commonly used to implement Modbus slave instances.

Specified by:

createResponse in class ModbusRequest

Parameters:

listener - Listener that received the request

Returns:

the corresponding ModbusResponse.

getReference

public int getReference()

Returns the reference of the register to to start reading from with this ReadCoilsRequest.

Returns:

the reference of the register to start reading from as int.

setReference

public void setReference(int ref)

Sets the reference of the register to start reading from with this ReadCoilsRequest.

Parameters:

ref - the reference of the register to start reading from.

getBitCount

public int getBitCount()

Returns the number of bits (i.e. coils) to be read with this ReadCoilsRequest.

Returns:

the number of bits to be read.

setBitCount

public void setBitCount(int count)

Sets the number of bits (i.e. coils) to be read with this ReadCoilsRequest.

Parameters:

count - the number of bits to be read.

writeData

public void writeData(DataOutput dout)
               throws IOException

Description copied from class: ModbusMessageImpl

Writes the subclass specific data to the given DataOutput.

Specified by:

writeData in class ModbusMessageImpl

Parameters:

dout - the DataOutput to be written to.

Throws:

IOException - if an I/O related error occurs.

readData

public void readData(DataInput din)
              throws IOException

Description copied from class: ModbusMessageImpl

Reads the subclass specific data from the given DataInput instance.

Specified by:

readData in class ModbusMessageImpl

Parameters:

din - the DataInput to read from.

Throws:

IOException - if an I/O related error occurs.

getMessage

public byte[] getMessage()

Description copied from interface: ModbusMessage

Returns the raw message as an array of bytes.

Returns:

the raw message as byte[].