Parameter (Geotools modules 21.0 API)

Object
- Parameter<T>

All Implemented Interfaces:

Parameter<T>

Direct Known Subclasses:

DataAccessFactory.Param
```
public class Parameter<T>
extends Object
implements Parameter<T>
```
A Parameter defines information about a valid process parameter.

Author:

gdavis

Field Summary

Fields
Modifier and Type	Field and Description
`static String`	`CRS` "crs": CoordinateReferenceSystem used to restrict a Geometry literal
`static String`	`DEPRECATED` Set parameter to deprecated - true, false ;can be used to conditional show the parameter based on deprecated value
`InternationalString`	`description` Human readable description of this parameter.
`static String`	`ELEMENT` "element": Class to use as the Element type for List.
`static String`	`EXT` File extension expected - "shp", "jpg", etc...
`static String`	`FEATURE_TYPE` "featureType" FeatureType to validate a Feature value against
`static String`	`IS_LARGE_TEXT` Boolean indicating whether the parameter is meant to be a long text, provides a hint for UI's use long text fields, textareas and the like
`static String`	`IS_PASSWORD` Boolean indicating whether the parameter shall be used as a password field, provides a hint for UI's to mask text fields, configuration systems to encrypt content, etc
`String`	`key` This is the key (ie machine readable text) used to represent this parameter in a java.util.Map.
`static String`	`LENGTH` "length" Integer used to limit the length of strings or literal geometries.
`static String`	`LEVEL` Level or Category of the parameter - "user", "advanced", "program" user - should be shown to all users and is used every time.
`static String`	`MAX` "min" and "max" may be useful for restrictions for things like int sizes, etc.
`int`	`maxOccurs`
`Map<String,Object>`	`metadata` Refinement of type; such as the FeatureType of a FeatureCollection, or component type of a List.
`static String`	`MIN` "min" and "max" may be useful for restrictions for things like int sizes, etc.
`int`	`minOccurs` What is the min and max number of this paramter there can be ( a value of -1 for min means 0 or more, a value of -1 for max means any number greater than or equal to the min value ) eg: a geometry union process can have any number of geom parameters, so by setting the max to -1 and the min to 2 we accomplish that.
`static String`	`OPTIONS` As an alternative to "min" and "max" a speciifc List of options can be provided for a user to choose between.
`boolean`	`required` Can the value be missing?
`Object`	`sample` A sample value; often used as a default when prompting the end-user to fill in the details before executing a process.
`InternationalString`	`title` Human readable title/name of this parameter.
`Class<T>`	`type` Class binding for this parameter.

Constructor Summary

Constructors
Constructor and Description
`Parameter(String key, Class<T> type)` Constructs a parameter from key and type
`Parameter(String key, Class<T> type, InternationalString title, InternationalString description)` Mandatory parameter
`Parameter(String key, Class<T> type, InternationalString title, InternationalString description, boolean required, int min, int max, Object sample, Map<String,Object> metadata)` Addition of optional parameters
`Parameter(String key, Class<T> type, InternationalString title, InternationalString description, Map<String,Object> metadata)` Mandatory parameter with metadata.
`Parameter(String key, Class<T> type, int min, int max)` Constructs a parameter from key, type, and min/max occurs.
`Parameter(String key, Class<T> type, String title, String description)` Mandatory parameter - quickly constructed with out a properly internationalized title and description.
`Parameter(String key, Class<T> type, String title, String description, Map<String,Object> metadata)` Mandatory parameter - quickly constructed with out a properly internationalized title and description.

Method Summary

All Methods Instance Methods Concrete Methods
Modifier and Type	Method and Description
`boolean`	`equals(Object obj)`
`T`	`getDefaultValue()` A default value for the parameter.
`InternationalString`	`getDescription()` Description of the parameter.
`String`	`getLevel()` Easy access to check the `LEVEL` metadata
`int`	`getMaxOccurs()` The maximum number of occurrences of the parameter.
`int`	`getMinOccurs()` The minimum number of occurrences of the parameter.
`String`	`getName()` Name of the parameter.
`InternationalString`	`getTitle()` Title of the parameter.
`Class<T>`	`getType()` Type/class of the parameter.
`int`	`hashCode()`
`Boolean`	`isDeprecated()` Easy access to check the `DEPRECATED` metadata
`boolean`	`isPassword()` Provides for easy access to the `IS_PASSWORD` metadata
`Boolean`	`isRequired()` Flag indicating if the parameter is required or not.
`String`	`toString()`

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

- Field Detail
  - key
```
public final String key
```
    This is the key (ie machine readable text) used to represent this parameter in a java.util.Map.
  - title
```
public final InternationalString title
```
    Human readable title/name of this parameter.
  - description
```
public final InternationalString description
```
    Human readable description of this parameter.
  - type
```
public final Class<T> type
```
    Class binding for this parameter.
    When a value is supplied for this key it should be of the provided type.
  - required
```
public final boolean required
```
    Can the value be missing? Or is null allowed...
  - minOccurs
```
public final int minOccurs
```
    What is the min and max number of this paramter there can be ( a value of -1 for min means 0 or more, a value of -1 for max means any number greater than or equal to the min value )
    eg: a geometry union process can have any number of geom parameters, so by setting the max to -1 and the min to 2 we accomplish that.
  - maxOccurs
```
public final int maxOccurs
```
  - sample
```
public final Object sample
```
    A sample value; often used as a default when prompting the end-user to fill in the details before executing a process.
  - FEATURE_TYPE
```
public static final String FEATURE_TYPE
```
    "featureType" FeatureType to validate a Feature value against
    
    See Also:
    
    Constant Field Values
  - IS_PASSWORD
```
public static final String IS_PASSWORD
```
    Boolean indicating whether the parameter shall be used as a password field, provides a hint for UI's to mask text fields, configuration systems to encrypt content, etc
    
    See Also:
    
    Constant Field Values
  - IS_LARGE_TEXT
```
public static final String IS_LARGE_TEXT
```
    Boolean indicating whether the parameter is meant to be a long text, provides a hint for UI's use long text fields, textareas and the like
    
    See Also:
    
    Constant Field Values
  - LENGTH
```
public static final String LENGTH
```
    "length" Integer used to limit the length of strings or literal geometries.
    
    See Also:
    
    Constant Field Values
  - CRS
```
public static final String CRS
```
    "crs": CoordinateReferenceSystem used to restrict a Geometry literal
    
    See Also:
    
    Constant Field Values
  - ELEMENT
```
public static final String ELEMENT
```
    "element": Class to use as the Element type for List. Please restrict your use of this facility to simple types; for most higher order data structures multiplicity is already accounted for - example MultiGeometry.
    
    See Also:
    
    Constant Field Values
  - MIN
```
public static final String MIN
```
    "min" and "max" may be useful for restrictions for things like int sizes, etc.
    
    See Also:
    
    Constant Field Values
  - MAX
```
public static final String MAX
```
    "min" and "max" may be useful for restrictions for things like int sizes, etc.
    
    See Also:
    
    Constant Field Values
  - OPTIONS
```
public static final String OPTIONS
```
    As an alternative to "min" and "max" a speciifc List of options can be provided for a user to choose between. The description should explain what the options mean.
    Example: a compliance level of (0-low,1-medium,2-high)
    Although a List is used here (so you can specifiy order) it is assumed you will not confuse your users by placing duplicates in the list.
    
    See Also:
    
    Constant Field Values
  - EXT
```
public static final String EXT
```
    File extension expected - "shp", "jpg", etc...
    
    See Also:
    
    Constant Field Values
  - LEVEL
```
public static final String LEVEL
```
    Level or Category of the parameter - "user", "advanced", "program"
    - user - should be shown to all users and is used every time.
      example: user name and password
    - advanced - advanced or expert parameter used in special cases
      example: choice between get and post requests for WFS
    - program - intended for programs often tweaking settings for performance
      example: JDBC datasource for which it is hard for a user to type in
    See Also:
    
    Constant Field Values
  - DEPRECATED
```
public static final String DEPRECATED
```
    Set parameter to deprecated - true, false ;can be used to conditional show the parameter based on deprecated value
    
    See Also:
    
    Constant Field Values
  - metadata
```
public final Map<String,Object> metadata
```
    Refinement of type; such as the FeatureType of a FeatureCollection, or component type of a List.
    This information is supplied (along with type) to allow a process implementor communicate additional restrictions on the allowed value beyond the strict type.
    The following keys are understood at this time: LENGTH, FEATURE_TYPE, CRS, ELEMENT .. additional keys will be documented as static final fields over time.
    Any restrictions mentioned here should be mentioned as part of your parameter description. This metadata is only used to help restrict what the user enters; not all client application will understand and respect these keys - please communicate with your end-user.
    
    See Also:
    
    CRS, ELEMENT, FEATURE_TYPE, IS_PASSWORD, LENGTH, MAX, MIN
- Constructor Detail
  - Parameter
```
public Parameter(String key,
                 Class<T> type,
                 String title,
                 String description)
```
    Mandatory parameter - quickly constructed with out a properly internationalized title and description.
    
    Parameters:
    
    key - machine readable key for use in a java.util.Map
    
    type - Java class for the expected value
    
    title - Human readable title used for use in a user interface
    
    description - Human readable description
  - Parameter
```
public Parameter(String key,
                 Class<T> type,
                 String title,
                 String description,
                 Map<String,Object> metadata)
```
    Mandatory parameter - quickly constructed with out a properly internationalized title and description.
    
    Parameters:
    
    key - machine readable key for use in a java.util.Map
    
    type - Java class for the expected value
    
    title - Human readable title used for use in a user interface
    
    description - Human readable description
  - Parameter
```
public Parameter(String key,
                 Class<T> type,
                 InternationalString title,
                 InternationalString description)
```
    Mandatory parameter
    
    Parameters:
    
    key - machine readable key for use in a java.util.Map
    
    type - Java class for the expected value
    
    title - Human readable title used for use in a user interface
    
    description - Human readable description
  - Parameter
```
public Parameter(String key,
                 Class<T> type,
                 InternationalString title,
                 InternationalString description,
                 Map<String,Object> metadata)
```
    Mandatory parameter with metadata.
    
    Parameters:
    
    key - machine readable key for use in a java.util.Map
    
    type - Java class for the expected value
    
    title - Human readable title used for use in a user interface
    
    description - Human readable description
    
    metadata - Hints to the user interface (read the javadocs for each metadata key)
    
    See Also:
    
    CRS, ELEMENT, FEATURE_TYPE, IS_PASSWORD, LENGTH, MAX, MIN
  - Parameter
```
public Parameter(String key,
                 Class<T> type,
                 InternationalString title,
                 InternationalString description,
                 boolean required,
                 int min,
                 int max,
                 Object sample,
                 Map<String,Object> metadata)
```
    Addition of optional parameters
    
    Parameters:
    
    key - machine readable key for use in a java.util.Map
    
    type - Java class for the expected value
    
    title - Human readable title used for use in a user interface
    
    description - Human readable description
    
    required - true if the value is required
    
    min - Minimum value; or -1 if not needed
    
    max - Maximum value; or -1 for unbound
    
    sample - Sample value; may be used as a default in a user interface
    
    metadata - Hints to the user interface (read the javadocs for each metadata key)
    
    See Also:
    
    CRS, ELEMENT, FEATURE_TYPE, IS_PASSWORD, LENGTH, MAX, MIN
  - Parameter
```
public Parameter(String key,
                 Class<T> type)
```
    Constructs a parameter from key and type
    
    Parameters:
    
    key - machine readable key for use in a java.util.Map
    
    type - Java class for the expected value
  - Parameter
```
public Parameter(String key,
                 Class<T> type,
                 int min,
                 int max)
```
    Constructs a parameter from key, type, and min/max occurs.
    
    Parameters:
    
    key - machine readable key for use in a java.util.Map
    
    type - Java class for the expected value
    
    min - Minimum value of occurrences, -1 if not needed
    
    max - Maximum value of occurrences, -1 for unbound
- Method Detail
  - getName
```
public String getName()
```
    Description copied from interface: Parameter
    
    Name of the parameter.
    
    Specified by:
    
    getName in interface Parameter<T>
  - getTitle
```
public InternationalString getTitle()
```
    Description copied from interface: Parameter
    
    Title of the parameter.
    
    Specified by:
    
    getTitle in interface Parameter<T>
  - getDescription
```
public InternationalString getDescription()
```
    Description copied from interface: Parameter
    
    Description of the parameter.
    
    Specified by:
    
    getDescription in interface Parameter<T>
  - getType
```
public Class<T> getType()
```
    Description copied from interface: Parameter
    
    Type/class of the parameter.
    
    Specified by:
    
    getType in interface Parameter<T>
  - isRequired
```
public Boolean isRequired()
```
    Description copied from interface: Parameter
    
    Flag indicating if the parameter is required or not.
    
    Specified by:
    
    isRequired in interface Parameter<T>
  - getMinOccurs
```
public int getMinOccurs()
```
    Description copied from interface: Parameter
    
    The minimum number of occurrences of the parameter.
    
    Specified by:
    
    getMinOccurs in interface Parameter<T>
    
    Returns:
    
    minimum number of occurrences, or -1 if no minimum needed
  - getMaxOccurs
```
public int getMaxOccurs()
```
    Description copied from interface: Parameter
    
    The maximum number of occurrences of the parameter.
    
    Specified by:
    
    getMaxOccurs in interface Parameter<T>
    
    Returns:
    
    maximum number of occurences, or -1 for unbound
  - getDefaultValue
```
public T getDefaultValue()
```
    Description copied from interface: Parameter
    
    A default value for the parameter.
    
    Specified by:
    
    getDefaultValue in interface Parameter<T>
  - isPassword
```
public boolean isPassword()
```
    Provides for easy access to the IS_PASSWORD metadata
    
    Returns:
    
    true if metadata.get(IS_PASSWORD) == Boolean.TRUE
  - isDeprecated
```
public Boolean isDeprecated()
```
    Easy access to check the DEPRECATED metadata
    
    Returns:
    
    provided deprecated or false by default
  - getLevel
```
public String getLevel()
```
    Easy access to check the LEVEL metadata
    
    Returns:
    
    provided level or "user" by default
  - toString
```
public String toString()
```
    Overrides:
    
    toString in class Object
  - hashCode
```
public int hashCode()
```
    Overrides:
    
    hashCode in class Object
  - equals
```
public boolean equals(Object obj)
```
    Overrides:
    
    equals in class Object

Class Parameter<T>

Field Summary

Constructor Summary

Method Summary

Methods inherited from class Object

Field Detail

key

title

description

type

required

minOccurs

maxOccurs

sample

FEATURE_TYPE

IS_PASSWORD

IS_LARGE_TEXT

LENGTH

CRS

ELEMENT

MIN

MAX

OPTIONS

EXT

LEVEL

DEPRECATED

metadata

Constructor Detail

Parameter

Parameter

Parameter

Parameter

Parameter

Parameter

Parameter

Method Detail

getName

getTitle

getDescription

getType

isRequired

getMinOccurs

getMaxOccurs

getDefaultValue

isPassword

isDeprecated

getLevel

toString

hashCode

equals