uk.ac.ed.epcc.webapp.content

Enum Operator

java.lang.Object

java.lang.Enum<Operator>

uk.ac.ed.epcc.webapp.content.Operator

All Implemented Interfaces:

java.io.Serializable, java.lang.Comparable<Operator>

public enum Operator
extends java.lang.Enum<Operator>

A supported binary operators on objects. usually used to define operations on Tables. If both arguments are number/null these mostly map onto the operations in NumberOp. The exception is the DIV DIV operator that promotes to double rather than preserving the behaviour of integer types. MIN and MAX will use the Comparable interface if possible. Otherwise if the first argument is not null it will be returned, otherwise the second.

Enum Constant Summary

Enum Constants

Enum Constant and Description
ADD
AVG
DIV
MAX
MEDIAN
MERGE
MIN
MUL
SUB

Method Summary

Modifier and Type	Method and Description
abstract java.lang.Object	operate(java.lang.Object a, java.lang.Object b)
static Operator	valueOf(java.lang.String name) Returns the enum constant of this type with the specified name.
static Operator[]	values() Returns an array containing the constants of this enum type, in the order they are declared.

Methods inherited from class java.lang.Enum

clone, compareTo, equals, finalize, getDeclaringClass, hashCode, name, ordinal, toString, valueOf

Methods inherited from class java.lang.Object

getClass, notify, notifyAll, wait, wait, wait

Enum Constant Detail

ADD

public static final Operator ADD

SUB

public static final Operator SUB

MUL

public static final Operator MUL

DIV

public static final Operator DIV

MIN

public static final Operator MIN

MAX

public static final Operator MAX

AVG

public static final Operator AVG

MEDIAN

public static final Operator MEDIAN

MERGE

public static final Operator MERGE

Method Detail

values

public static Operator[] values()

Returns an array containing the constants of this enum type, in the order they are declared. This method may be used to iterate over the constants as follows:

for (Operator c : Operator.values())
    System.out.println(c);

Returns:

an array containing the constants of this enum type, in the order they are declared

valueOf

public static Operator valueOf(java.lang.String name)

Returns the enum constant of this type with the specified name. The string must match exactly an identifier used to declare an enum constant in this type. (Extraneous whitespace characters are not permitted.)

Parameters:

name - the name of the enum constant to be returned.

Returns:

the enum constant with the specified name

Throws:

java.lang.IllegalArgumentException - if this enum type has no constant with the specified name

java.lang.NullPointerException - if the argument is null

operate

public abstract java.lang.Object operate(java.lang.Object a,
                                         java.lang.Object b)