NumberHelper (MPXJ 13.8.0 API)

java.lang.Object
- net.sf.mpxj.common.NumberHelper

```
public final class NumberHelper
extends Object
```
This class contains utility methods for handling Number objects and numeric primitives.

Field Summary

Fields
Modifier and Type Field and Description

static Double DOUBLE_ZERO

Fields
Modifier and Type	Field and Description
`static Double`	`DOUBLE_ZERO`

Constructor Summary

Constructors
Constructor and Description

NumberHelper()

Constructors
Constructor and Description
`NumberHelper()`

Method Summary

All Methods Static Methods Concrete Methods
Modifier and Type	Method and Description
`static int`	`compare(Integer n1, Integer n2)` Compare two integers, accounting for null values.
`static boolean`	`equals(double lhs, double rhs, double delta)` Compares two doubles for equality, within an allowable range of difference.
`static boolean`	`equals(Number lhs, Number rhs)` This method is used to compare two numbers.
`static BigInteger`	`getBigInteger(Number value)` Utility method used to convert a Number into a BigInteger.
`static Double`	`getDouble(double value)` Utility method used to convert a double into a Double.
`static double`	`getDouble(Number value)` Utility method used to convert a Number into a double.
`static double`	`getDouble(String value)` This method retrieves a double value from a String instance.
`static Double`	`getDoubleObject(String value)` This method retrieves a double value from a String instance.
`static int`	`getInt(Number value)` This method retrieves an int value from a Number instance.
`static int`	`getInt(String value)` This method retrieves an int value from a String instance.
`static Integer`	`getInteger(Number value)` Utility method used to convert an arbitrary Number into an Integer.
`static Integer`	`getInteger(String value)` Converts a string representation of an integer into an Integer object.
`static Integer`	`parseInteger(String value)` Utility method to convert a String to an Integer, and handles null values.
`static double`	`round(double value, double precision)` Utility method used to round a double to the given precision.
`static Double`	`sumAsDouble(Number... values)` Calculate the sum of a list of numbers and express the result as a Double instance.

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

- Field Detail
  - DOUBLE_ZERO
```
public static final Double DOUBLE_ZERO
```
- Constructor Detail
  - NumberHelper
```
public NumberHelper()
```
- Method Detail
  - getInt
```
public static final int getInt(Number value)
```
    This method retrieves an int value from a Number instance. It returns zero by default if a null value is supplied.
    
    Parameters:
    
    value - Number instance
    
    Returns:
    
    int value
  - getInt
```
public static final int getInt(String value)
```
    This method retrieves an int value from a String instance. It returns zero by default if a null value or an empty string is supplied.
    
    Parameters:
    
    value - string representation of an integer
    
    Returns:
    
    int value
  - getDouble
```
public static final double getDouble(String value)
```
    This method retrieves a double value from a String instance. It returns zero by default if a null value or an empty string is supplied.
    
    Parameters:
    
    value - string representation of a double
    
    Returns:
    
    double value
  - getDoubleObject
```
public static final Double getDoubleObject(String value)
```
    This method retrieves a double value from a String instance. It returns null by default if a null value or an empty string is supplied.
    
    Parameters:
    
    value - string representation of a double
    
    Returns:
    
    double value
  - getInteger
```
public static final Integer getInteger(Number value)
```
    Utility method used to convert an arbitrary Number into an Integer.
    
    Parameters:
    
    value - Number instance
    
    Returns:
    
    Integer instance
  - getInteger
```
public static final Integer getInteger(String value)
```
    Converts a string representation of an integer into an Integer object. Silently ignores any parse exceptions and returns null.
    
    Parameters:
    
    value - String representation of an integer
    
    Returns:
    
    Integer instance
  - getBigInteger
```
public static final BigInteger getBigInteger(Number value)
```
    Utility method used to convert a Number into a BigInteger.
    
    Parameters:
    
    value - Number instance
    
    Returns:
    
    BigInteger instance
  - getDouble
```
public static final double getDouble(Number value)
```
    Utility method used to convert a Number into a double. This has been implemented to allow a singleton to be used to represent zero. This makes a considerable saving in memory utilisation.
    
    Parameters:
    
    value - Number instance
    
    Returns:
    
    double value
  - getDouble
```
public static final Double getDouble(double value)
```
    Utility method used to convert a double into a Double. This has been implemented to allow a singleton to be used to represent zero. This makes a considerable saving in memory utilisation. NOTE: as of Java 1.5 the Double.valueOf method is supposed to implement caching. The current JDK 1.5 implementation doesn't appear to do this, so we'll leave this method alone for now. We can look at replacing this when we move to 1.6.
    
    Parameters:
    
    value - Number instance
    
    Returns:
    
    double value
  - round
```
public static final double round(double value,
                                 double precision)
```
    Utility method used to round a double to the given precision.
    
    Parameters:
    
    value - value to truncate
    
    precision - Number of decimals to round to.
    
    Returns:
    
    double value
  - parseInteger
```
public static final Integer parseInteger(String value)
```
    Utility method to convert a String to an Integer, and handles null values.
    
    Parameters:
    
    value - string representation of an integer
    
    Returns:
    
    int value
  - equals
```
public static boolean equals(Number lhs,
                             Number rhs)
```
    This method is used to compare two numbers. The unusual point about this method is that it takes account of null values. If the two number objects are both null, these are taken to be equal, if one is null and the other is not null, these are taken to be different. Finally, if we have two valid number objects, these are compared in the normal manner to determine equality.
    
    Parameters:
    
    lhs - left hand argument
    
    rhs - right hand argument
    
    Returns:
    
    result of equality test
  - compare
```
public static int compare(Integer n1,
                          Integer n2)
```
    Compare two integers, accounting for null values.
    
    Parameters:
    
    n1 - integer value
    
    n2 - integer value
    
    Returns:
    
    comparison result
  - equals
```
public static boolean equals(double lhs,
                             double rhs,
                             double delta)
```
    Compares two doubles for equality, within an allowable range of difference.
    
    Parameters:
    
    lhs - value to test
    
    rhs - value to test
    
    delta - allowable difference
    
    Returns:
    
    boolean value
  - sumAsDouble
```
public static Double sumAsDouble(Number... values)
```
    Calculate the sum of a list of numbers and express the result as a Double instance.
    
    Parameters:
    
    values - list of numbers
    
    Returns:
    
    Double instance

Class NumberHelper

Field Summary

Constructor Summary

Method Summary

Methods inherited from class java.lang.Object

Field Detail

DOUBLE_ZERO

Constructor Detail

NumberHelper

Method Detail

getInt

getInt

getDouble

getDoubleObject

getInteger

getInteger

getBigInteger

getDouble

getDouble

round

parseInteger

equals

compare

equals

sumAsDouble