Variant (org.eclipse.scada 0.2.1.RC4 API)

java.lang.Object
- org.eclipse.scada.core.Variant

All Implemented Interfaces:

Serializable, Comparable<Variant>
```
public class Variant
extends Object
implements Serializable, Comparable<Variant>
```
A variant data type that can hold any scalar value type.

Author:

Jens Reimann <jens.reimann@th4-systems.com>

See Also:
Serialized Form

Field Summary

Fields
Modifier and Type	Field and Description
`static Variant`	`FALSE` A default BOOL#false instance
`static Variant`	`NULL` A default NULL instance
`static Variant`	`TRUE` A default BOOL#true instance

Constructor Summary

Constructors
Modifier	Constructor and Description
`protected`	`Variant()`
`protected`	`Variant(boolean value)`
`protected`	`Variant(double value)`
`protected`	`Variant(int value)`
`protected`	`Variant(long value)`
`protected`	`Variant(Object object)`
`protected`	`Variant(String value)`
`protected`	`Variant(Variant other)`

Method Summary

Methods
Modifier and Type	Method and Description
`Serializable`	`as(VariantType variantType)` Convert the variant to a java object of the type specified by the variantType parameter
`Serializable`	`as(VariantType variantType, Serializable defaultValue)` Convert the variant to a java object of the type specified by the variantType parameter
`boolean`	`asBoolean()` Get the value as boolean value If the value is `null` then `false` is returned.
`Boolean`	`asBoolean(Boolean defaultValue)` Return the value as boolean
`double`	`asDouble()`
`Double`	`asDouble(Double defaultValue)`
`int`	`asInteger()`
`Integer`	`asInteger(Integer defaultValue)`
`long`	`asLong()`
`Long`	`asLong(Long defaultValue)`
`String`	`asString()` Get the string representation of the variant value.
`String`	`asString(String defaultValue)` Get the string representation of the variant value or a default value if the variant is of type `VariantType.NULL`.
`int`	`compareTo(Variant o)`
`boolean`	`equals(Object obj)`
`VariantType`	`getType()`
`Serializable`	`getValue()` Get the internal variant value
`int`	`hashCode()`
`boolean`	`isBoolean()`
`boolean`	`isDouble()`
`boolean`	`isInteger()`
`boolean`	`isLong()`
`boolean`	`isNull()`
`boolean`	`isNumber()`
`boolean`	`isString()`
`String`	`toLabel()`
`String`	`toLabel(String defaultLabel)`
`String`	`toString()` Get the string representation of the variant (not the variant value).
`static Variant`	`valueOf(boolean value)`
`static Variant`	`valueOf(double value)`
`static Variant`	`valueOf(int value)`
`static Variant`	`valueOf(long value)`
`static Variant`	`valueOf(Object value)`

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

- Field Detail
  - NULL
```
public static final Variant NULL
```
    A default NULL instance
  - TRUE
```
public static final Variant TRUE
```
    A default BOOL#true instance
  - FALSE
```
public static final Variant FALSE
```
    A default BOOL#false instance
- Constructor Detail
  - Variant
```
protected Variant()
```
  - Variant
```
protected Variant(Object object)
```
  - Variant
```
protected Variant(boolean value)
```
  - Variant
```
protected Variant(double value)
```
  - Variant
```
protected Variant(int value)
```
  - Variant
```
protected Variant(long value)
```
  - Variant
```
protected Variant(String value)
```
  - Variant
```
protected Variant(Variant other)
```
- Method Detail
  - valueOf
```
public static Variant valueOf(long value)
```
  - valueOf
```
public static Variant valueOf(int value)
```
  - valueOf
```
public static Variant valueOf(double value)
```
  - valueOf
```
public static Variant valueOf(boolean value)
```
  - valueOf
```
public static Variant valueOf(Object value)
```
  - isNull
```
public boolean isNull()
```
  - asString
```
public String asString()
                throws NullValueException
```
    Get the string representation of the variant value.
    
    Returns:
    The string representation of the variant value.
    
    Throws:
    
    NullValueException - thrown if the variant if of type VariantType.NULL
  - asString
```
public String asString(String defaultValue)
```
    Get the string representation of the variant value or a default value if the variant is of type VariantType.NULL.
    
    Returns:
    The string representation of the variant value or the default value.
  - asDouble
```
public Double asDouble(Double defaultValue)
```
    Parameters:
    defaultValue - the default value
    
    Returns:
    the value as a double or the default value if the value cannot be provided as a double
  - asDouble
```
public double asDouble()
                throws NullValueException,
                       NotConvertableException
```
    Throws:
    
    NullValueException
    
    NotConvertableException
  - asInteger
```
public Integer asInteger(Integer defaultValue)
```
    Parameters:
    defaultValue - the default value
    
    Returns:
    the value as an integer or the default value if the value cannot be provided as an integer
  - asInteger
```
public int asInteger()
              throws NullValueException,
                     NotConvertableException
```
    Throws:
    
    NullValueException
    
    NotConvertableException
  - asLong
```
public Long asLong(Long defaultValue)
```
    Parameters:
    defaultValue - the default value
    
    Returns:
    the value as a long or the default value if the value cannot be provided as a long
  - asLong
```
public long asLong()
            throws NullValueException,
                   NotConvertableException
```
    Throws:
    
    NullValueException
    
    NotConvertableException
  - asBoolean
```
public boolean asBoolean()
```
    Get the value as boolean value If the value is null then false is returned. If the value is a boolean it will simply return the value itself. If the value is a numeric value (double, long, integer) is will return false if the value zero and true otherwise. If the value is a string then false is returned if the string is empty. If the string can be converted to a number (long or double) it will be compared to that number. Otherwise it will be compared case insensitive against the string
```
 true
 
```
    .
    Returns:
    The boolean value of this variant
  - asBoolean
```
public Boolean asBoolean(Boolean defaultValue)
```
    Return the value as boolean
    
    Parameters:
    defaultValue - the default value
    
    Returns:
    the value as a boolean or the default value if the value is null
  - as
```
public Serializable as(VariantType variantType,
              Serializable defaultValue)
```
    Convert the variant to a java object of the type specified by the variantType parameter
    The default value must be of the type of the variant type parameter, otherwise a class cast exception will be thrown. The default value may also be null.
    
    Parameters:
    variantType - the variant type to convert to (may be null)
    defaultValue - the default value in case the conversion fails or the variant is NULL
    
    Returns:
    the resulting java object
    See Also:
    as(VariantType)
  - as
```
public Serializable as(VariantType variantType)
                throws NullValueException,
                       NotConvertableException
```
    Convert the variant to a java object of the type specified by the variantType parameter
    The method converts the current variant to a plain java Serializable of the requested type. For the list of types than can be expected see the java type field of VariantType.
    
    There are some special cases for this method:
    - If the parameter variantType is null the java object currently set will be returned without any conversion
    - If the variant type VariantType.UNKNOWN is requested the java object currently set will be returned without any conversion
    - If the VariantType.NULL is requested always null will be returned
    Parameters:
    variantType - the target type
    
    Returns:
    the resulting java object
    
    Throws:
    
    NullValueException - in case the variant was of type null and should be converted to some other type
    
    NotConvertableException - in case the variant cannot be converted to the target value
  - isBoolean
```
public boolean isBoolean()
```
  - isString
```
public boolean isString()
```
  - isDouble
```
public boolean isDouble()
```
  - isInteger
```
public boolean isInteger()
```
  - isLong
```
public boolean isLong()
```
  - isNumber
```
public boolean isNumber()
```
  - equals
```
public boolean equals(Object obj)
```
    Overrides:
    
    equals in class Object
  - hashCode
```
public int hashCode()
```
    Overrides:
    
    hashCode in class Object
  - toLabel
```
public String toLabel(String defaultLabel)
```
  - toLabel
```
public String toLabel()
```
  - toString
```
public String toString()
```
    Get the string representation of the variant (not the variant value). This includes also the variant type.
    The format is VariantType#VariantValue.
    If you want to get the string representation of the variant value itself use asString() instead.
    
    Overrides:
    
    toString in class Object
  - getType
```
public VariantType getType()
```
    Returns:
    type from Type enumeration fitting for current value
  - getValue
```
public Serializable getValue()
```
    Get the internal variant value
    
    Returns:
    the internal variant value
  - compareTo
```
public int compareTo(Variant o)
```
    Specified by:
    
    compareTo in interface Comparable<Variant>

Class Variant

Field Summary

Constructor Summary

Method Summary

Methods inherited from class java.lang.Object

Field Detail

NULL

TRUE

FALSE

Constructor Detail

Variant

Variant

Variant

Variant

Variant

Variant

Variant

Variant

Method Detail

valueOf

valueOf

valueOf

valueOf

valueOf

isNull

asString

asString

asDouble

asDouble

asInteger

asInteger

asLong

asLong

asBoolean

asBoolean

as

as

isBoolean

isString

isDouble

isInteger

isLong

isNumber

equals

hashCode

toLabel

toLabel

toString

getType

getValue

compareTo