ModbusUtil (j2mod 3.3.0 API)

java.lang.Object
- com.ghgande.j2mod.modbus.util.ModbusUtil

```
public class ModbusUtil
extends Object
```
Helper class that provides utility methods.

Version:

2.0 (March 2016)

Author:

Dieter Wimberger, John Charlton, Steve O'Hara (4NG)

Method Summary

All Methods Static Methods Concrete Methods
Modifier and Type	Method and Description
`static int[]`	`calculateCRC(byte[] data, int offset, int len)`
`static byte[]`	`doubleToRegisters(double d)` Converts a double value to a byte[8].
`static byte[]`	`floatToRegisters(float f)` Converts a float value to a byte[4] binary float value.
`static byte`	`hiByte(int wd)`
`static byte[]`	`intToRegisters(int v)` Converts an int value to a byte[4] array.
`static boolean`	`isBlank(List<Object> list)` Return true if the list is null or empty
`static boolean`	`isBlank(Object[] list)` Return true if the array is null or empty
`static boolean`	`isBlank(String value)` Return true if the string is null or empty
`static byte[]`	`longToRegisters(long v)` Converts a long value to a byte[8].
`static byte`	`lowByte(int wd)` Returns the low byte of an integer word.
`static int`	`makeWord(int hibyte, int lowbyte)` Makes a word from 2 bytes
`static double`	`registersToDouble(byte[] bytes)` Converts a byte[8] binary double value into a double primitive.
`static float`	`registersToFloat(byte[] bytes)` Converts a byte[4] binary float value to a float primitive.
`static int`	`registersToInt(byte[] bytes)` Converts a byte[4] binary int value to a primitive int. The value returned is:
`static long`	`registersToLong(byte[] bytes)` Converts a byte[8] binary long value into a long primitive.
`static short`	`registerToShort(byte[] bytes)` Converts the given register (16-bit value) into a `short`.
`static short`	`registerToShort(byte[] bytes, int idx)` Converts the register (16-bit value) at the given index into a `short`.
`static int`	`registerToUnsignedShort(byte[] bytes)` Converts the register (a 16 bit value) into an unsigned short.
`static byte[]`	`shortToRegister(short s)` Converts the given `short` into a register (2 bytes).
`static void`	`sleep(long time)` Sleeps safely for the specified amount of time unless awoken by an interruption
`static String`	`toHex(byte[] data)` Returns the given byte[] as hex encoded string.
`static String`	`toHex(byte[] data, int off, int end)` Returns a `String` containing unsigned hexadecimal numbers as digits.
`static byte[]`	`toHex(int i)` Returns a `byte[]` containing the given byte as unsigned hexadecimal number digits.
`static String`	`toHex(ModbusMessage msg)` Converts a `ModbusMessage` instance into a hex encoded string representation.
`static int`	`unsignedByteToInt(byte b)` Converts an unsigned byte to an integer.
`static byte[]`	`unsignedShortToRegister(int v)` Converts the given unsigned short into a register (2 bytes).

Methods inherited from class java.lang.Object
equals, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

- Method Detail
  - toHex
```
public static String toHex(ModbusMessage msg)
```
    Converts a ModbusMessage instance into a hex encoded string representation.
    
    Parameters:
    
    msg - the message to be converted.
    
    Returns:
    
    the converted hex encoded string representation of the message.
  - toHex
```
public static String toHex(byte[] data)
```
    Returns the given byte[] as hex encoded string.
    
    Parameters:
    
    data - a byte[] array.
    
    Returns:
    
    a hex encoded String.
  - toHex
```
public static String toHex(byte[] data,
                           int off,
                           int end)
```
    Returns a String containing unsigned hexadecimal numbers as digits. The String will coontain two hex digit characters for each byte from the passed in byte[].
    The bytes will be separated by a space character.
    
    Parameters:
    
    data - the array of bytes to be converted into a hex-string.
    
    off - the offset to start converting from.
    
    end - the offset of the end of the byte array.
    
    Returns:
    
    the generated hexadecimal representation as String.
  - toHex
```
public static byte[] toHex(int i)
```
    Returns a byte[] containing the given byte as unsigned hexadecimal number digits.
    
    Parameters:
    
    i - the int to be converted into a hex string.
    
    Returns:
    
    the generated hexadecimal representation as byte[].
  - registerToUnsignedShort
```
public static int registerToUnsignedShort(byte[] bytes)
```
    Converts the register (a 16 bit value) into an unsigned short. The value returned is:
```
(((a & 0xff) << 8) | (b & 0xff))
```
    This conversion has been taken from the documentation of the DataInput interface.
    Parameters:
    
    bytes - a register as byte[2].
    
    Returns:
    
    the unsigned short value as int.
    
    See Also:
    
    DataInput
  - unsignedShortToRegister
```
public static byte[] unsignedShortToRegister(int v)
```
    Converts the given unsigned short into a register (2 bytes). The byte values in the register, in the order shown, are:
```
 (byte)(0xff & (v >> 8))
 (byte)(0xff & v)
 
```
    This conversion has been taken from the documentation of the DataOutput interface.
    Parameters:
    
    v - Value to convert
    
    Returns:
    
    the register as byte[2].
    
    See Also:
    
    DataOutput
  - registerToShort
```
public static short registerToShort(byte[] bytes)
```
    Converts the given register (16-bit value) into a short. The value returned is:
```
 (short)((a << 8) | (b & 0xff))
 
```
    This conversion has been taken from the documentation of the DataInput interface.
    Parameters:
    
    bytes - bytes a register as byte[2].
    
    Returns:
    
    the signed short as short.
  - registerToShort
```
public static short registerToShort(byte[] bytes,
                                    int idx)
```
    Converts the register (16-bit value) at the given index into a short. The value returned is:
```
 (short)((a << 8) | (b & 0xff))
 
```
    This conversion has been taken from the documentation of the DataInput interface.
    Parameters:
    
    bytes - a byte[] containing a short value.
    
    idx - an offset into the given byte[].
    
    Returns:
    
    the signed short as short.
  - shortToRegister
```
public static byte[] shortToRegister(short s)
```
    Converts the given short into a register (2 bytes). The byte values in the register, in the order shown, are:
```
 (byte)(0xff & (v >> 8))
 (byte)(0xff & v)
 
```
    Parameters:
    
    s - Value to convert
    
    Returns:
    
    a register containing the given short value.
  - registersToInt
```
public static int registersToInt(byte[] bytes)
```
    Converts a byte[4] binary int value to a primitive int.
    The value returned is:
```
 (((a & 0xff) << 24) | ((b & 0xff) << 16) |
  ((c & 0xff) << 8) | (d & 0xff))
 
```
    Parameters:
    
    bytes - registers as byte[4].
    
    Returns:
    
    the integer contained in the given register bytes.
  - intToRegisters
```
public static byte[] intToRegisters(int v)
```
    Converts an int value to a byte[4] array.
    
    Parameters:
    
    v - the value to be converted.
    
    Returns:
    
    a byte[4] containing the value.
  - registersToLong
```
public static long registersToLong(byte[] bytes)
```
    Converts a byte[8] binary long value into a long primitive.
    
    Parameters:
    
    bytes - a byte[8] containing a long value.
    
    Returns:
    
    a long value.
  - longToRegisters
```
public static byte[] longToRegisters(long v)
```
    Converts a long value to a byte[8].
    
    Parameters:
    
    v - the value to be converted.
    
    Returns:
    
    a byte[8] containing the long value.
  - registersToFloat
```
public static float registersToFloat(byte[] bytes)
```
    Converts a byte[4] binary float value to a float primitive.
    
    Parameters:
    
    bytes - the byte[4] containing the float value.
    
    Returns:
    
    a float value.
  - floatToRegisters
```
public static byte[] floatToRegisters(float f)
```
    Converts a float value to a byte[4] binary float value.
    
    Parameters:
    
    f - the float to be converted.
    
    Returns:
    
    a byte[4] containing the float value.
  - registersToDouble
```
public static double registersToDouble(byte[] bytes)
```
    Converts a byte[8] binary double value into a double primitive.
    
    Parameters:
    
    bytes - a byte[8] to be converted.
    
    Returns:
    
    a double value.
  - doubleToRegisters
```
public static byte[] doubleToRegisters(double d)
```
    Converts a double value to a byte[8].
    
    Parameters:
    
    d - the double to be converted.
    
    Returns:
    
    a byte[8].
  - unsignedByteToInt
```
public static int unsignedByteToInt(byte b)
```
    Converts an unsigned byte to an integer.
    
    Parameters:
    
    b - the byte to be converted.
    
    Returns:
    
    an integer containing the unsigned byte value.
  - lowByte
```
public static byte lowByte(int wd)
```
    Returns the low byte of an integer word.
    
    Parameters:
    
    wd - word to get low byte from
    
    Returns:
    
    low byte of word
  - hiByte
```
public static byte hiByte(int wd)
```
    Parameters:
    
    wd - word to get high byte from
    
    Returns:
    
    high byte
  - makeWord
```
public static int makeWord(int hibyte,
                           int lowbyte)
```
    Makes a word from 2 bytes
    
    Parameters:
    
    hibyte - High byte
    
    lowbyte - Low byte
    
    Returns:
    
    Word
  - calculateCRC
```
public static int[] calculateCRC(byte[] data,
                                 int offset,
                                 int len)
```
  - isBlank
```
public static boolean isBlank(String value)
```
    Return true if the string is null or empty
    
    Parameters:
    
    value - String to check
    
    Returns:
    
    True if the value is blank or empty
  - isBlank
```
public static boolean isBlank(List<Object> list)
```
    Return true if the list is null or empty
    
    Parameters:
    
    list - List to check
    
    Returns:
    
    True if the list is blank or empty
  - isBlank
```
public static boolean isBlank(Object[] list)
```
    Return true if the array is null or empty
    
    Parameters:
    
    list - Array to check
    
    Returns:
    
    True if the array is blank or empty
  - sleep
```
public static void sleep(long time)
```
    Sleeps safely for the specified amount of time unless awoken by an interruption
    
    Parameters:
    
    time - Time in milliseconds

Class ModbusUtil

Method Summary

Methods inherited from class java.lang.Object

Method Detail

toHex

toHex

toHex

toHex

registerToUnsignedShort

unsignedShortToRegister

registerToShort

registerToShort

shortToRegister

registersToInt

intToRegisters

registersToLong

longToRegisters

registersToFloat

floatToRegisters

registersToDouble

doubleToRegisters

unsignedByteToInt

lowByte

hiByte

makeWord

calculateCRC

isBlank

isBlank

isBlank

sleep