Aggregate (Geotools modules 28-SNAPSHOT API)

Object
- Enum<Aggregate>
- - Aggregate

All Implemented Interfaces:

Serializable, Comparable<Aggregate>
```
public enum Aggregate
extends Enum<Aggregate>
```
Aggregate functions defined for use with the GeoTools library.
Aggregates are backed by a FeatureCalc visitor for direct use with a FeatureCollection (or use with GroupByVisitor ). THe create(Expression) method is used as a factory method to configure an appropriate visitor.
During processing a CalcResult is used to store intermediate results. Implementations that handle an aggregate function directly (such as JDBCDataStore) can use can use the wrap method to generate the expect CalcResult from a calculated raw value.

Enum Constant Summary

Enum Constants
Enum Constant and Description

AVERAGE

COUNT

MAX

MEDIAN

MIN

STD_DEV

SUM

SUMAREA

Enum Constants
Enum Constant and Description
`AVERAGE`
`COUNT`
`MAX`
`MEDIAN`
`MIN`
`STD_DEV`
`SUM`
`SUMAREA`

Method Summary

All Methods Static Methods Instance Methods Abstract Methods Concrete Methods
Modifier and Type	Method and Description
`abstract FeatureCalc`	`create(Expression expression)` Factory method creating a visitor using an aggregate attribute.
`abstract Class`	`getTargetType(Class inputType)` Retruns the type of the result, given the type of the input.
`static Aggregate`	`valueOf(String name)` Returns the enum constant of this type with the specified name.
`static Aggregate`	`valueOfIgnoreCase(String visitorName)` Helper method that given a visitor name returns the appropriate enum constant.
`static Aggregate[]`	`values()` Returns an array containing the constants of this enum type, in the order they are declared.
`abstract CalcResult`	`wrap(Expression expression, Object value)` Wraps a raw value in the appropriate visitor calculation result.

Methods inherited from class Enum
clone, compareTo, equals, finalize, getDeclaringClass, hashCode, name, ordinal, toString, valueOf

Methods inherited from class Object
getClass, notify, notifyAll, wait, wait, wait

- Enum Constant Detail
  - AVERAGE
```
public static final Aggregate AVERAGE
```
  - COUNT
```
public static final Aggregate COUNT
```
  - MAX
```
public static final Aggregate MAX
```
  - MEDIAN
```
public static final Aggregate MEDIAN
```
  - MIN
```
public static final Aggregate MIN
```
  - STD_DEV
```
public static final Aggregate STD_DEV
```
  - SUM
```
public static final Aggregate SUM
```
  - SUMAREA
```
public static final Aggregate SUMAREA
```
- Method Detail
  - values
```
public static Aggregate[] 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 (Aggregate c : Aggregate.values())
    System.out.println(c);
```
    Returns:
    
    an array containing the constants of this enum type, in the order they are declared
  - valueOf
```
public static Aggregate valueOf(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:
    
    IllegalArgumentException - if this enum type has no constant with the specified name
    
    NullPointerException - if the argument is null
  - create
```
public abstract FeatureCalc create(Expression expression)
```
    Factory method creating a visitor using an aggregate attribute.
    
    Parameters:
    
    expression - Expression used to sample collection (often a PropertyName)
    
    Returns:
    
    a new instance of the visitor
  - wrap
```
public abstract CalcResult wrap(Expression expression,
                                Object value)
```
    Wraps a raw value in the appropriate visitor calculation result. The typical usage of this is to wrap values returned by stores able to handle the visitor (for example the JDBCDataStore).
    
    Parameters:
    
    expression - Expression used to sample collection (often a PropertyName)
    
    value - The raw value to be wrapped
    
    Returns:
    
    value Wrapped in the appropriate visitor calculation result
  - getTargetType
```
public abstract Class getTargetType(Class inputType)
```
    Retruns the type of the result, given the type of the input. Will throw an exception if the input type is not acceptable
    
    Returns:
  - valueOfIgnoreCase
```
public static Aggregate valueOfIgnoreCase(String visitorName)
```
    Helper method that given a visitor name returns the appropriate enum constant.
    The performed match by name is more permissive that the default one. The match will not be case sensitive and slightly different names can be used (camel case versus snake case).
    
    Parameters:
    
    visitorName - the visitor name
    
    Returns:
    
    this enum constant that machs the visitor name

Enum Aggregate

Enum Constant Summary

Method Summary

Methods inherited from class Enum

Methods inherited from class Object

Enum Constant Detail

AVERAGE

COUNT

MAX

MEDIAN

MIN

STD_DEV

SUM

SUMAREA

Method Detail

values

valueOf

create

wrap

getTargetType

valueOfIgnoreCase