com.ghgande.j2mod.modbus.facade

Class AbstractModbusMaster

java.lang.Object

com.ghgande.j2mod.modbus.facade.AbstractModbusMaster

Direct Known Subclasses:

ModbusSerialMaster, ModbusTCPMaster, ModbusUDPMaster

public abstract class AbstractModbusMaster
extends Object

Modbus/TCP Master facade - common methods for all the facade implementations The emphasis is in making callas to Modbus devices as simple as possible for the most common Function Codes. This class makes sure that no NPE is raised and that the methods are thread-safe.

Version:

2.0 (March 2016)

Author:

Steve O'Hara (4NG)

Constructor Summary

Constructors

Constructor and Description
AbstractModbusMaster()

Method Summary

Modifier and Type	Method and Description
abstract void	connect() Connects this ModbusTCPMaster with the slave.
abstract void	disconnect() Disconnects this ModbusTCPMaster from the slave.
int	getTimeout() Returns the receive timeout in milliseconds
abstract AbstractModbusTransport	getTransport() Returns the transport being used by the
abstract boolean	isConnected() Returns true if the master is connected
boolean	maskWriteRegister(int ref, int andMask, int orMask) Mask write a single register to the slave.
boolean	maskWriteRegister(int unitId, int ref, int andMask, int orMask) Mask write a single register to the slave.
BitVector	readCoils(int ref, int count) Reads a given number of coil states from the slave.
BitVector	readCoils(int unitId, int ref, int count) Reads a given number of coil states from the slave.
BitVector	readInputDiscretes(int ref, int count) Reads a given number of input discrete states from the slave.
BitVector	readInputDiscretes(int unitId, int ref, int count) Reads a given number of input discrete states from the slave.
InputRegister[]	readInputRegisters(int ref, int count) Reads a given number of input registers from the slave.
InputRegister[]	readInputRegisters(int unitId, int ref, int count) Reads a given number of input registers from the slave.
Register[]	readMultipleRegisters(int ref, int count) Reads a given number of registers from the slave.
Register[]	readMultipleRegisters(int unitId, int ref, int count) Reads a given number of registers from the slave.
void	setCheckingValidity(boolean b) Sets the flag that controls whether the validity of a transaction will be checked.
void	setRetries(int retries) Set the amount of retries for opening the connection for executing the transaction.
void	setTimeout(int timeout) Sets the receive timeout
boolean	writeCoil(int ref, boolean state) Writes a coil state to the slave.
boolean	writeCoil(int unitId, int ref, boolean state) Writes a coil state to the slave.
void	writeMultipleCoils(int ref, BitVector coils) Writes a given number of coil states to the slave.
void	writeMultipleCoils(int unitId, int ref, BitVector coils) Writes a given number of coil states to the slave.
int	writeMultipleRegisters(int unitId, int ref, Register[] registers) Writes a number of registers to the slave.
int	writeMultipleRegisters(int ref, Register[] registers) Writes a number of registers to the slave.
int	writeSingleRegister(int unitId, int ref, Register register) Writes a single register to the slave.
int	writeSingleRegister(int ref, Register register) Writes a single register to the slave.

Methods inherited from class java.lang.Object

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

Constructor Detail

AbstractModbusMaster

public AbstractModbusMaster()

Method Detail

connect

public abstract void connect()
                      throws Exception

Connects this ModbusTCPMaster with the slave.

Throws:

Exception - if the connection cannot be established.

disconnect

public abstract void disconnect()

Disconnects this ModbusTCPMaster from the slave.

readCoils

public BitVector readCoils(int unitId,
                           int ref,
                           int count)
                    throws ModbusException

Reads a given number of coil states from the slave. Note that the number of bits in the bit vector will be forced to the number originally requested.

Parameters:

unitId - the slave unit id.

ref - the offset of the coil to start reading from.

count - the number of coil states to be read.

Returns:

a BitVector instance holding the received coil states.

Throws:

ModbusException - if an I/O error, a slave exception or a transaction error occurs.

writeCoil

public boolean writeCoil(int unitId,
                         int ref,
                         boolean state)
                  throws ModbusException

Writes a coil state to the slave.

Parameters:

unitId - the slave unit id.

ref - the offset of the coil to be written.

state - the coil state to be written.

Returns:

the state of the coil as returned from the slave.

Throws:

ModbusException - if an I/O error, a slave exception or a transaction error occurs.

writeMultipleCoils

public void writeMultipleCoils(int unitId,
                               int ref,
                               BitVector coils)
                        throws ModbusException

Writes a given number of coil states to the slave. Note that the number of coils to be written is given implicitly, through BitVector.size().

Parameters:

unitId - the slave unit id.

ref - the offset of the coil to start writing to.

coils - a BitVector which holds the coil states to be written.

Throws:

ModbusException - if an I/O error, a slave exception or a transaction error occurs.

readInputDiscretes

public BitVector readInputDiscretes(int unitId,
                                    int ref,
                                    int count)
                             throws ModbusException

Reads a given number of input discrete states from the slave. Note that the number of bits in the bit vector will be forced to the number originally requested.

Parameters:

unitId - the slave unit id.

ref - the offset of the input discrete to start reading from.

count - the number of input discrete states to be read.

Returns:

a BitVector instance holding the received input discrete states.

Throws:

ModbusException - if an I/O error, a slave exception or a transaction error occurs.

readInputRegisters

public InputRegister[] readInputRegisters(int unitId,
                                          int ref,
                                          int count)
                                   throws ModbusException

Reads a given number of input registers from the slave. Note that the number of input registers returned (i.e. array length) will be according to the number received in the slave response.

Parameters:

unitId - the slave unit id.

ref - the offset of the input register to start reading from.

count - the number of input registers to be read.

Returns:

a InputRegister[] with the received input registers.

Throws:

ModbusException - if an I/O error, a slave exception or a transaction error occurs.

readMultipleRegisters

public Register[] readMultipleRegisters(int unitId,
                                        int ref,
                                        int count)
                                 throws ModbusException

Reads a given number of registers from the slave. Note that the number of registers returned (i.e. array length) will be according to the number received in the slave response.

Parameters:

unitId - the slave unit id.

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

count - the number of registers to be read.

Returns:

a Register[] holding the received registers.

Throws:

ModbusException - if an I/O error, a slave exception or a transaction error occurs.

writeSingleRegister

public int writeSingleRegister(int unitId,
                               int ref,
                               Register register)
                        throws ModbusException

Writes a single register to the slave.

Parameters:

unitId - the slave unit id.

ref - the offset of the register to be written.

register - a Register holding the value of the register to be written.

Returns:

the value of the register as returned from the slave.

Throws:

ModbusException - if an I/O error, a slave exception or a transaction error occurs.

writeMultipleRegisters

public int writeMultipleRegisters(int unitId,
                                  int ref,
                                  Register[] registers)
                           throws ModbusException

Writes a number of registers to the slave.

Parameters:

unitId - the slave unit id.

ref - the offset of the register to start writing to.

registers - a Register[] holding the values of the registers to be written.

Returns:

the number of registers that have been written.

Throws:

ModbusException - if an I/O error, a slave exception or a transaction error occurs.

maskWriteRegister

public boolean maskWriteRegister(int unitId,
                                 int ref,
                                 int andMask,
                                 int orMask)
                          throws ModbusException

Mask write a single register to the slave.

Parameters:

unitId - the slave unit id.

ref - the offset of the register to start writing to.

andMask - AND mask.

orMask - OR mask.

Returns:

true if success, i.e. response data equals to request data, false otherwise.

Throws:

ModbusException - if an I/O error, a slave exception or a transaction error occurs.

readCoils

public BitVector readCoils(int ref,
                           int count)
                    throws ModbusException

Reads a given number of coil states from the slave. Note that the number of bits in the bit vector will be forced to the number originally requested.

Parameters:

ref - the offset of the coil to start reading from.

count - the number of coil states to be read.

Returns:

a BitVector instance holding the received coil states.

Throws:

ModbusException - if an I/O error, a slave exception or a transaction error occurs.

writeCoil

public boolean writeCoil(int ref,
                         boolean state)
                  throws ModbusException

Writes a coil state to the slave.

Parameters:

ref - the offset of the coil to be written.

state - the coil state to be written.

Returns:

the state of the coil as returned from the slave.

Throws:

ModbusException - if an I/O error, a slave exception or a transaction error occurs.

writeMultipleCoils

public void writeMultipleCoils(int ref,
                               BitVector coils)
                        throws ModbusException

Writes a given number of coil states to the slave. Note that the number of coils to be written is given implicitly, through BitVector.size().

Parameters:

ref - the offset of the coil to start writing to.

coils - a BitVector which holds the coil states to be written.

Throws:

ModbusException - if an I/O error, a slave exception or a transaction error occurs.

readInputDiscretes

public BitVector readInputDiscretes(int ref,
                                    int count)
                             throws ModbusException

Reads a given number of input discrete states from the slave. Note that the number of bits in the bit vector will be forced to the number originally requested.

Parameters:

ref - the offset of the input discrete to start reading from.

count - the number of input discrete states to be read.

Returns:

a BitVector instance holding the received input discrete states.

Throws:

ModbusException - if an I/O error, a slave exception or a transaction error occurs.

readInputRegisters

public InputRegister[] readInputRegisters(int ref,
                                          int count)
                                   throws ModbusException

Reads a given number of input registers from the slave. Note that the number of input registers returned (i.e. array length) will be according to the number received in the slave response.

Parameters:

ref - the offset of the input register to start reading from.

count - the number of input registers to be read.

Returns:

a InputRegister[] with the received input registers.

Throws:

ModbusException - if an I/O error, a slave exception or a transaction error occurs.

readMultipleRegisters

public Register[] readMultipleRegisters(int ref,
                                        int count)
                                 throws ModbusException

Reads a given number of registers from the slave. Note that the number of registers returned (i.e. array length) will be according to the number received in the slave response.

Parameters:

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

count - the number of registers to be read.

Returns:

a Register[] holding the received registers.

Throws:

ModbusException - if an I/O error, a slave exception or a transaction error occurs.

writeSingleRegister

public int writeSingleRegister(int ref,
                               Register register)
                        throws ModbusException

Writes a single register to the slave.

Parameters:

ref - the offset of the register to be written.

register - a Register holding the value of the register to be written.

Returns:

the value of the register as returned from the slave.

Throws:

ModbusException - if an I/O error, a slave exception or a transaction error occurs.

writeMultipleRegisters

public int writeMultipleRegisters(int ref,
                                  Register[] registers)
                           throws ModbusException

Writes a number of registers to the slave.

Parameters:

ref - the offset of the register to start writing to.

registers - a Register[] holding the values of the registers to be written.

Returns:

the number of registers that have been written.

Throws:

ModbusException - if an I/O error, a slave exception or a transaction error occurs.

maskWriteRegister

public boolean maskWriteRegister(int ref,
                                 int andMask,
                                 int orMask)
                          throws ModbusException

Mask write a single register to the slave.

Parameters:

ref - the offset of the register to start writing to.

andMask - AND mask.

orMask - OR mask.

Returns:

true if success, i.e. response data equals to request data, false otherwise.

Throws:

ModbusException - if an I/O error, a slave exception or a transaction error occurs.

getTimeout

public int getTimeout()

Returns the receive timeout in milliseconds

Returns:

Timeout in milliseconds

setTimeout

public void setTimeout(int timeout)

Sets the receive timeout

Parameters:

timeout - Timeout in milliseconds

setRetries

public void setRetries(int retries)

Set the amount of retries for opening the connection for executing the transaction.

Parameters:

retries - the amount of retries as int.

setCheckingValidity

public void setCheckingValidity(boolean b)

Sets the flag that controls whether the validity of a transaction will be checked.

Parameters:

b - true if checking validity, false otherwise.

getTransport

public abstract AbstractModbusTransport getTransport()

Returns the transport being used by the

Returns:

ModbusTransport

isConnected

public abstract boolean isConnected()

Returns true if the master is connected

Returns:

True if connected