Package com.singularsys.extensions.field

Class FieldCollection

java.lang.Object

com.singularsys.extensions.field.FieldCollection

All Implemented Interfaces:

FieldI, IntegerConvertor, java.io.Serializable

Direct Known Subclasses:

MatrixFieldCollection

public class FieldCollection
extends java.lang.Object
implements FieldI, IntegerConvertor

Groups a set of fields together. Fields can be added to the collection by calling addField(SetI). When evaluating each field is evaluated in turn, if the result is non null then that value is returned. Otherwise the next field is checked.

The collection also implements the FieldMethodsI encapsulating the the operations as Binary/Unary Methods, so it can be used directly with a FieldOperatorTable.

Author:

Richard Morris

See Also:

Serialized Form

Field Summary

Fields

Modifier and Type	Field	Description
protected java.util.List<FieldI>	fields

Constructor Summary

Constructors

Constructor	Description
FieldCollection()	Standard constructor with no fields.
FieldCollection(FieldI... fields)	Constructor from a set of fields.

Method Summary

Modifier and Type	Method	Description
java.lang.Object	add(java.lang.Object l, java.lang.Object r)	Add two members of the field.
void	addField(FieldI f)	Add a new field to the collection.
java.lang.Boolean	and(java.lang.Object l, java.lang.Object r)	Logical and.
void	clearFields()
java.lang.Object	convertFromInt(java.lang.Integer l)	Attempt to convert argument from an integer
java.lang.Integer	convertToInt(java.lang.Object l)	Attempt to convert argument to an integer
java.lang.Object	div(java.lang.Object l, java.lang.Object r)	Divides two members of the field.
java.lang.Boolean	eq(java.lang.Object l, java.lang.Object r)	Equals
java.lang.Boolean	ge(java.lang.Object l, java.lang.Object r)	Greater or equal to
FieldI[]	getFields()
java.lang.Object	getOne()	Get the multiplicative identity for this field.
java.lang.Object	getZero()	Get the additive identity for this field
java.lang.Boolean	gt(java.lang.Object l, java.lang.Object r)	Greater than
java.lang.Boolean	le(java.lang.Object l, java.lang.Object r)	Less than or equals to
java.lang.Boolean	lt(java.lang.Object l, java.lang.Object r)	Less than
java.lang.Object	mod(java.lang.Object l, java.lang.Object r)	The modulus of two members of the field.
java.lang.Object	mul(java.lang.Object l, java.lang.Object r)	Multiplies two members of the field.
java.lang.Boolean	ne(java.lang.Object l, java.lang.Object r)	Not Equals
java.lang.Object	neg(java.lang.Object l)	The negation -x of an element.
java.lang.Boolean	not(java.lang.Object l)	Logical not.
java.lang.Boolean	or(java.lang.Object l, java.lang.Object r)	Logical or.
java.lang.Object	pow(java.lang.Object l, java.lang.Object r)	The power operator.
boolean	removeField(FieldI e)
java.lang.Object	sub(java.lang.Object l, java.lang.Object r)	Subtract two members of the field.

Methods inherited from class java.lang.Object

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

Field Detail

fields

protected java.util.List<FieldI> fields

Constructor Detail

FieldCollection

public FieldCollection()

Standard constructor with no fields.

FieldCollection

public FieldCollection(FieldI... fields)

Constructor from a set of fields.

Parameters:

fields - a list of fields in order

Method Detail

addField

public void addField(FieldI f)

Add a new field to the collection.

Parameters:

f - the field to add

removeField

public boolean removeField(FieldI e)

clearFields

public void clearFields()

getFields

public FieldI[] getFields()

add

public java.lang.Object add(java.lang.Object l,
                            java.lang.Object r)
                     throws EvaluationException

Description copied from interface: FieldI

Add two members of the field.

Specified by:

add in interface FieldI

Parameters:

l - left hand argument

r - right hand argument

Returns:

an object representing the result or null if it can not be evaluated.

Throws:

EvaluationException - on error

sub

public java.lang.Object sub(java.lang.Object l,
                            java.lang.Object r)
                     throws EvaluationException

Description copied from interface: FieldI

Subtract two members of the field.

Specified by:

sub in interface FieldI

Parameters:

l - left hand argument

r - right hand argument

Returns:

an object representing the result or null if it can not be evaluated.

Throws:

EvaluationException - on error

neg

public java.lang.Object neg(java.lang.Object l)
                     throws EvaluationException

Description copied from interface: FieldI

The negation -x of an element.

Specified by:

neg in interface FieldI

Parameters:

l - the argument

Returns:

an object representing the result or null if it can not be evaluated.

Throws:

EvaluationException - on error

mul

public java.lang.Object mul(java.lang.Object l,
                            java.lang.Object r)
                     throws EvaluationException

Description copied from interface: FieldI

Multiplies two members of the field.

Specified by:

mul in interface FieldI

Parameters:

l - left hand argument

r - right hand argument

Returns:

an object representing the result or null if it can not be evaluated.

Throws:

EvaluationException - on error

div

public java.lang.Object div(java.lang.Object l,
                            java.lang.Object r)
                     throws EvaluationException

Description copied from interface: FieldI

Divides two members of the field.

Specified by:

div in interface FieldI

Parameters:

l - left hand argument

r - right hand argument

Returns:

an object representing the result or null if it can not be evaluated.

Throws:

EvaluationException - on error

mod

public java.lang.Object mod(java.lang.Object l,
                            java.lang.Object r)
                     throws EvaluationException

Description copied from interface: FieldI

The modulus of two members of the field.

Specified by:

mod in interface FieldI

Parameters:

l - left hand argument

r - right hand argument

Returns:

an object representing the result or null if it can not be evaluated.

Throws:

EvaluationException - on error

pow

public java.lang.Object pow(java.lang.Object l,
                            java.lang.Object r)
                     throws EvaluationException

Description copied from interface: FieldI

The power operator.

Specified by:

pow in interface FieldI

Parameters:

l - left hand argument

r - right hand argument

Returns:

an object representing the result or null if it can not be evaluated.

Throws:

EvaluationException - on error

eq

public java.lang.Boolean eq(java.lang.Object l,
                            java.lang.Object r)
                     throws EvaluationException

Description copied from interface: FieldI

Equals

Specified by:

eq in interface FieldI

Parameters:

l - left hand argument

r - right hand argument

Returns:

an object representing the result or null if it can not be evaluated.

Throws:

EvaluationException - on error

ne

public java.lang.Boolean ne(java.lang.Object l,
                            java.lang.Object r)
                     throws EvaluationException

Description copied from interface: FieldI

Not Equals

Specified by:

ne in interface FieldI

Parameters:

l - left hand argument

r - right hand argument

Returns:

an object representing the result or null if it can not be evaluated.

Throws:

EvaluationException - on error

gt

public java.lang.Boolean gt(java.lang.Object l,
                            java.lang.Object r)
                     throws EvaluationException

Description copied from interface: FieldI

Greater than

Specified by:

gt in interface FieldI

Parameters:

l - left hand argument

r - right hand argument

Returns:

an object representing the result or null if it can not be evaluated.

Throws:

EvaluationException - on error

ge

public java.lang.Boolean ge(java.lang.Object l,
                            java.lang.Object r)
                     throws EvaluationException

Description copied from interface: FieldI

Greater or equal to

Specified by:

ge in interface FieldI

Parameters:

l - left hand argument

r - right hand argument

Returns:

an object representing the result or null if it can not be evaluated.

Throws:

EvaluationException - on error

lt

public java.lang.Boolean lt(java.lang.Object l,
                            java.lang.Object r)
                     throws EvaluationException

Description copied from interface: FieldI

Less than

Specified by:

lt in interface FieldI

Parameters:

l - left hand argument

r - right hand argument

Returns:

an object representing the result or null if it can not be evaluated.

Throws:

EvaluationException - on error

le

public java.lang.Boolean le(java.lang.Object l,
                            java.lang.Object r)
                     throws EvaluationException

Description copied from interface: FieldI

Less than or equals to

Specified by:

le in interface FieldI

Parameters:

l - left hand argument

r - right hand argument

Returns:

an object representing the result or null if it can not be evaluated.

Throws:

EvaluationException - on error

and

public java.lang.Boolean and(java.lang.Object l,
                             java.lang.Object r)
                      throws EvaluationException

Description copied from interface: FieldI

Logical and.

Specified by:

and in interface FieldI

Parameters:

l - left hand argument implimentation

r - right hand argument

Returns:

an object representing the result or null if it can not be evaluated.

Throws:

EvaluationException - on error

or

public java.lang.Boolean or(java.lang.Object l,
                            java.lang.Object r)
                     throws EvaluationException

Description copied from interface: FieldI

Logical or.

Specified by:

or in interface FieldI

Parameters:

l - left hand argument

r - right hand argument

Returns:

an object representing the result or null if it can not be evaluated.

Throws:

EvaluationException - on error

not

public java.lang.Boolean not(java.lang.Object l)
                      throws EvaluationException

Description copied from interface: FieldI

Logical not.

Specified by:

not in interface FieldI

Parameters:

l - argument

Returns:

an object representing the result or null if it can not be evaluated.

Throws:

EvaluationException - on error

getOne

public java.lang.Object getOne()

Description copied from interface: FieldI

Get the multiplicative identity for this field.

Specified by:

getOne in interface FieldI

Returns:

object representing one or null if undefined for this field

getZero

public java.lang.Object getZero()

Description copied from interface: FieldI

Get the additive identity for this field

Specified by:

getZero in interface FieldI

Returns:

object representing zero or null if undefined for this field

convertToInt

public java.lang.Integer convertToInt(java.lang.Object l)
                               throws EvaluationException

Description copied from interface: IntegerConvertor

Attempt to convert argument to an integer

Specified by:

convertToInt in interface IntegerConvertor

Parameters:

l - value to convert

Returns:

corresponding integer or null if it cannot be converted

Throws:

EvaluationException - on error

convertFromInt

public java.lang.Object convertFromInt(java.lang.Integer l)
                                throws EvaluationException

Description copied from interface: IntegerConvertor

Attempt to convert argument from an integer

Specified by:

convertFromInt in interface IntegerConvertor

Parameters:

l - value to convert

Returns:

corresponding value in this field or null if it cannot be converted

Throws:

EvaluationException - probably never