com.ghgande.j2mod.modbus.msg

Class ModbusMessageImpl

java.lang.Object

com.ghgande.j2mod.modbus.msg.ModbusMessageImpl

All Implemented Interfaces:

ModbusMessage

Direct Known Subclasses:

ModbusRequest, ModbusResponse

public abstract class ModbusMessageImpl
extends Object
implements ModbusMessage

Abstract class implementing a ModbusMessage. This class provides specialised implementations with the functionality they have in common.

Version:

2.0 (March 2016)

Author:

Dieter Wimberger, Steve O'Hara (4NG)

Constructor Summary

Constructors

Constructor and Description
ModbusMessageImpl()

Method Summary

Modifier and Type	Method and Description
int	getDataLength() Returns the length of the data appended after the protocol header.
int	getFunctionCode() Returns the function code of this ModbusMessage as int. The function code is a 1-byte non negative integer value valid in the range of 0-127.
String	getHexMessage() Returns the raw message as String containing a hexadecimal series of bytes.
int	getOutputLength() Returns the number of bytes that will be written by ModbusMessage.writeTo(DataOutput).
int	getProtocolID() Returns the protocol identifier of this ModbusMessage as int.
int	getTransactionID() Returns the transaction identifier of this ModbusMessage as int.
int	getUnitID() Returns the unit identifier of this ModbusMessage as int.
boolean	isHeadless() Check the flag which indicates that this ModbusMessage is for a headless (serial, or headless networked) connection.
abstract void	readData(DataInput din) Reads the subclass specific data from the given DataInput instance.
void	readFrom(DataInput din) Reads this Transportable from the given DataInput.
void	setDataLength(int length) Sets the length of the data appended after the protocol header.
void	setHeadless() Sets the flag that marks this ModbusMessage as headless (for serial transport).
void	setHeadless(boolean b) Sets the headless flag of this message.
void	setProtocolID(int pid) Sets the protocol identifier of this ModbusMessage.
void	setTransactionID(int tid) Sets the transaction identifier of this ModbusMessage.
void	setUnitID(int num) Sets the unit identifier of this ModbusMessage. The identifier should be a 1-byte non negative integer value valid in the range of 0-255.
abstract void	writeData(DataOutput dout) Writes the subclass specific data to the given DataOutput.
void	writeTo(DataOutput dout) Writes this Transportable to the given DataOutput.

Methods inherited from class java.lang.Object

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

Methods inherited from interface com.ghgande.j2mod.modbus.msg.ModbusMessage

getMessage

Constructor Detail

ModbusMessageImpl

public ModbusMessageImpl()

Method Detail

isHeadless

public boolean isHeadless()

Description copied from interface: ModbusMessage

Check the flag which indicates that this ModbusMessage is for a headless (serial, or headless networked) connection.

Specified by:

isHeadless in interface ModbusMessage

Returns:

is for a headless (serial, or headless networked) connection

setHeadless

public void setHeadless()

Description copied from interface: ModbusMessage

Sets the flag that marks this ModbusMessage as headless (for serial transport).

Specified by:

setHeadless in interface ModbusMessage

getTransactionID

public int getTransactionID()

Description copied from interface: ModbusMessage

Returns the transaction identifier of this ModbusMessage as int.

The identifier is a 2-byte (short) non negative integer value valid in the range of 0-65535.

Specified by:

getTransactionID in interface ModbusMessage

Returns:

the transaction identifier as int.

setTransactionID

public void setTransactionID(int tid)

Sets the transaction identifier of this ModbusMessage.

The identifier must be a 2-byte (short) non negative integer value valid in the range of 0-65535.

Parameters:

tid - the transaction identifier as int.

getProtocolID

public int getProtocolID()

Description copied from interface: ModbusMessage

Returns the protocol identifier of this ModbusMessage as int.

The identifier is a 2-byte (short) non negative integer value valid in the range of 0-65535.

Specified by:

getProtocolID in interface ModbusMessage

Returns:

the protocol identifier as int.

setProtocolID

public void setProtocolID(int pid)

Sets the protocol identifier of this ModbusMessage.

The identifier should be a 2-byte (short) non negative integer value valid in the range of 0-65535.

Parameters:

pid - the protocol identifier as int.

getDataLength

public int getDataLength()

Description copied from interface: ModbusMessage

Returns the length of the data appended after the protocol header.

Specified by:

getDataLength in interface ModbusMessage

Returns:

the data length as int.

setDataLength

public void setDataLength(int length)

Sets the length of the data appended after the protocol header.

Note that this library, a bit in contrast to the specification, counts the unit identifier and the function code in the header, because it is part of each and every message. Thus this method will add two (2) to the passed in integer value.

This method does not include the length of a final CRC/LRC for those protocols which requirement.

Parameters:

length - the data length as int.

getUnitID

public int getUnitID()

Description copied from interface: ModbusMessage

Returns the unit identifier of this ModbusMessage as int.

The identifier is a 1-byte non negative integer value valid in the range of 0-255.

Specified by:

getUnitID in interface ModbusMessage

Returns:

the unit identifier as int.

setUnitID

public void setUnitID(int num)

Sets the unit identifier of this ModbusMessage.
The identifier should be a 1-byte non negative integer value valid in the range of 0-255.

Parameters:

num - the unit identifier number to be set.

getFunctionCode

public int getFunctionCode()

Description copied from interface: ModbusMessage

Returns the function code of this ModbusMessage as int.
The function code is a 1-byte non negative integer value valid in the range of 0-127.

Function codes are ordered in conformance classes their values are specified in com.ghgande.j2mod.modbus.Modbus.

Specified by:

getFunctionCode in interface ModbusMessage

Returns:

the function code as int.

See Also:

Modbus

getHexMessage

public String getHexMessage()

Description copied from interface: ModbusMessage

Returns the raw message as String containing a hexadecimal series of bytes.

This method is specially for debugging purposes, allowing the user to log the communication in a manner used in the specification document.

Specified by:

getHexMessage in interface ModbusMessage

Returns:

the raw message as String containing a hexadecimal series of bytes.

setHeadless

public void setHeadless(boolean b)

Sets the headless flag of this message.

Parameters:

b - true if headless, false otherwise.

getOutputLength

public int getOutputLength()

Description copied from interface: ModbusMessage

Returns the number of bytes that will be written by ModbusMessage.writeTo(DataOutput).

Specified by:

getOutputLength in interface ModbusMessage

Returns:

the number of bytes that will be written as int.

writeTo

public void writeTo(DataOutput dout)
             throws IOException

Description copied from interface: ModbusMessage

Writes this Transportable to the given DataOutput.

Specified by:

writeTo in interface ModbusMessage

Parameters:

dout - the DataOutput to write to.

Throws:

IOException - if an I/O error occurs.

readFrom

public void readFrom(DataInput din)
              throws IOException

Description copied from interface: ModbusMessage

Reads this Transportable from the given DataInput.

Specified by:

readFrom in interface ModbusMessage

Parameters:

din - the DataInput to read from.

Throws:

IOException - if an I/O error occurs or the data is invalid.

writeData

public abstract void writeData(DataOutput dout)
                        throws IOException

Writes the subclass specific data to the given DataOutput.

Parameters:

dout - the DataOutput to be written to.

Throws:

IOException - if an I/O related error occurs.

readData

public abstract void readData(DataInput din)
                       throws IOException

Reads the subclass specific data from the given DataInput instance.

Parameters:

din - the DataInput to read from.

Throws:

IOException - if an I/O related error occurs.