Package org.eclipse.core.commands

Class ParameterType

java.lang.Object

org.eclipse.core.commands.common.EventManager

org.eclipse.core.commands.common.HandleObject

org.eclipse.core.commands.ParameterType

All Implemented Interfaces:

Comparable, IIdentifiable

public final class ParameterType
extends HandleObject
implements Comparable

Provides information about the type of a command parameter. Clients can use a parameter type to check if an object matches the type of the parameter with isCompatible(Object) and can get an AbstractParameterValueConverter to convert between objects matching the parameter type and strings that encode the object's identity.

A command parameter is not required to declare a type. To determine if a given parameter has a type, check if an IParameter implements ITypedParameter and if so, use ITypedParameter.getParameterType() like this:

                   IParameter parameter = // ... get IParameter from Command
                   if (parameter instanceof ITypedParameter) {
                     ParameterType type = ((ITypedParameter)parameter).getParameterType();
                     if (type != null) {
                       // this parameter has a ParameterType
                     }
                   }
 

Since:

3.2

See Also:

IParameter, ITypedParameter.getParameterType()

Field Summary

Fields inherited from class org.eclipse.core.commands.common.HandleObject

defined, id, string

Method Summary

Modifier and Type	Method	Description
void	addListener(IParameterTypeListener listener)	Adds a listener to this parameter type that will be notified when its state changes.
int	compareTo(Object object)	Compares this parameter type with another object by comparing each of the non-transient attributes.
void	define(String type, AbstractParameterValueConverter parameterTypeConverter)	Defines this parameter type, setting the defined property to true.
AbstractParameterValueConverter	getValueConverter()	Returns the value converter associated with this parameter, if any.
boolean	isCompatible(Object value)	Returns whether the provided value is compatible with this parameter type.
void	removeListener(IParameterTypeListener listener)	Unregisters listener for changes to properties of this parameter type.
String	toString()	The string representation of this parameter type.
void	undefine()	Makes this parameter type become undefined.

Methods inherited from class org.eclipse.core.commands.common.HandleObject

equals, getId, hashCode, isDefined

Methods inherited from class org.eclipse.core.commands.common.EventManager

addListenerObject, clearListeners, getListeners, isListenerAttached, removeListenerObject

Methods inherited from class java.lang.Object

clone, finalize, getClass, notify, notifyAll, wait, wait, wait

Method Detail

addListener

public final void addListener(IParameterTypeListener listener)

Adds a listener to this parameter type that will be notified when its state changes.

Parameters:

listener - The listener to be added; must not be null.

compareTo

public final int compareTo(Object object)

Compares this parameter type with another object by comparing each of the non-transient attributes.

Specified by:

compareTo in interface Comparable

Parameters:

object - The object with which to compare; must be an instance of ParameterType.

Returns:

A negative integer, zero or a positive integer, if the object is greater than, equal to or less than this parameter type.

define

public final void define(String type,
                         AbstractParameterValueConverter parameterTypeConverter)

Defines this parameter type, setting the defined property to true.

Notification is sent to all listeners that something has changed.

Parameters:

type - a string identifying the Java object type for this parameter type; null is interpreted as "java.lang.Object"

parameterTypeConverter - an AbstractParameterValueConverter to perform string/object conversions for parameter values; may be null

getValueConverter

public final AbstractParameterValueConverter getValueConverter()
                                                        throws NotDefinedException

Returns the value converter associated with this parameter, if any.

Returns:

The parameter value converter, or null if there is no value converter for this parameter.

Throws:

NotDefinedException - if the parameter type is not currently defined

isCompatible

public boolean isCompatible(Object value)
                     throws NotDefinedException

Returns whether the provided value is compatible with this parameter type. An object is compatible with a parameter type if the object is an instance of the class defined as the parameter's type class.

Parameters:

value - an object to check for compatibility with this parameter type; may be null.

Returns:

true if the value is compatible with this type, false otherwise

Throws:

NotDefinedException - if the parameter type is not currently defined

removeListener

public final void removeListener(IParameterTypeListener listener)

Unregisters listener for changes to properties of this parameter type.

Parameters:

listener - the instance to unregister. Must not be null. If an attempt is made to unregister an instance which is not already registered with this instance, no operation is performed.

toString

public final String toString()

The string representation of this parameter type. For debugging purposes only. This string should not be shown to an end user.

Specified by:

toString in class HandleObject

Returns:

The string representation; never null.

undefine

public final void undefine()

Makes this parameter type become undefined. Notification is sent to all listeners.

Specified by:

undefine in class HandleObject