org.dmilne.xjsf.param

Class Parameter<T>

java.lang.Object

org.dmilne.xjsf.param.Parameter<T>

Type Parameters:

T - the type of value to expect.

Direct Known Subclasses:

BooleanParameter, EnumParameter, EnumSetParameter, FloatParameter, IntListParameter, IntParameter, StringArrayParameter, StringParameter

public abstract class Parameter<T>
extends Object

A parameter or argument for a service. Parameters should know how to extract their value from an HttpServletRequest and document themselves as an xml description.

Field Summary

Fields

Modifier and Type	Field and Description
protected HashMap<String,String>	valueDescriptionsByName

Constructor Summary

Constructors

Constructor and Description
Parameter(String name, String description, T defaultValue, String dataTypeName) Initialises a new parameter

Method Summary

Methods

Modifier and Type	Method and Description
T	getDefaultValue() Returns the value to be used if no value is manually specified in the service request.
String	getDescription() Returns a short textual description of what this parameter does
String	getName() Returns the name of the parameter
abstract T	getValue(javax.servlet.http.HttpServletRequest request) Returns the value of this parameter, as specified in the given request.
String	getValueForDescription(T val)

Methods inherited from class java.lang.Object

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

Field Detail

valueDescriptionsByName

protected HashMap<String,String> valueDescriptionsByName

Constructor Detail

Parameter

public Parameter(String name,
         String description,
         T defaultValue,
         String dataTypeName)

Initialises a new parameter

Parameters:

name - the name of the parameter

description - a short description of what this parameter does

defaultValue - the value to use when requests do not specify a value for this parameter (may be null)

Method Detail

getName

public String getName()

Returns the name of the parameter

Returns:

the name of the parameter

getDescription

public String getDescription()

Returns a short textual description of what this parameter does

Returns:

a short textual description of what this parameter does

getDefaultValue

public T getDefaultValue()

Returns the value to be used if no value is manually specified in the service request. This may be null, in which case the parameter is considered mandatory: all requests to the service must specify a value for this parameter

Returns:

the value to be used if none is manually specified in the service request.

getValueForDescription

public String getValueForDescription(T val)

getValue

public abstract T getValue(javax.servlet.http.HttpServletRequest request)
                    throws IllegalArgumentException

Returns the value of this parameter, as specified in the given request. If the request specifies an invalid value, or none at all, then the default value will be returned.

Parameters:

request - the request made to the service

Returns:

the value of this parameter, as specified in the given request.

Throws:

IllegalArgumentException - if the value specified in this request cannot be parsed