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* DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
*
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* under the terms of the GNU General Public License version 2 only, as
* published by the Free Software Foundation. Oracle designates this
* particular file as subject to the "Classpath" exception as provided
* by Oracle in the LICENSE file that accompanied this code.
*
* This code is distributed in the hope that it will be useful, but WITHOUT
* ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
* FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
* version 2 for more details (a copy is included in the LICENSE file that
* accompanied this code).
*
* You should have received a copy of the GNU General Public License version
* 2 along with this work; if not, write to the Free Software Foundation,
* Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
*
* Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
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package ajava.beans;
/**
* A PropertyEditor class provides support for GUIs that want to
* allow users to edit a property value of a given type.
*
* PropertyEditor supports a variety of different kinds of ways of
* displaying and updating property values. Most PropertyEditors will
* only need to support a subset of the different options available in
* this API.
*
* Simple PropertyEditors may only support the getAsText and setAsText
* methods and need not support (say) paintValue or getCustomEditor. More
* complex types may be unable to support getAsText and setAsText but will
* instead support paintValue and getCustomEditor.
*
* Every propertyEditor must support one or more of the three simple
* display styles. Thus it can either (1) support isPaintable or (2)
* both return a non-null String[] from getTags() and return a non-null
* value from getAsText or (3) simply return a non-null String from
* getAsText().
*
* Every property editor must support a call on setValue when the argument
* object is of the type for which this is the corresponding propertyEditor.
* In addition, each property editor must either support a custom editor,
* or support setAsText.
*
* Each PropertyEditor should have a null constructor.
*/
public interface PropertyEditor {
/**
* Set (or change) the object that is to be edited. Primitive types such
* as "int" must be wrapped as the corresponding object type such as
* "java.lang.Integer".
*
* @param value The new target object to be edited. Note that this
* object should not be modified by the PropertyEditor, rather
* the PropertyEditor should create a new object to hold any
* modified value.
*/
void setValue(Object value);
/**
* Gets the property value.
*
* @return The value of the property. Primitive types such as "int" will
* be wrapped as the corresponding object type such as "java.lang.Integer".
*/
Object getValue();
//----------------------------------------------------------------------
/**
* Determines whether this property editor is paintable.
*
* @return True if the class will honor the paintValue method.
*/
boolean isPaintable();
/**
* Paint a representation of the value into a given area of screen
* real estate. Note that the propertyEditor is responsible for doing
* its own clipping so that it fits into the given rectangle.
*
* If the PropertyEditor doesn't honor paint requests (see isPaintable)
* this method should be a silent noop.
*
* The given Graphics object will have the default font, color, etc of
* the parent container. The PropertyEditor may change graphics attributes
* such as font and color and doesn't need to restore the old values.
*
* @param gfx Graphics object to paint into.
* @param box Rectangle within graphics object into which we should paint.
*/
void paintValue(java.awt.Graphics gfx, java.awt.Rectangle box);
//----------------------------------------------------------------------
/**
* Returns a fragment of Java code that can be used to set a property
* to match the editors current state. This method is intended
* for use when generating Java code to reflect changes made through the
* property editor.
*
* The code fragment should be context free and must be a legal Java
* expression as specified by the JLS.
*
* Specifically, if the expression represents a computation then all
* classes and static members should be fully qualified. This rule
* applies to constructors, static methods and non primitive arguments.
*
* Caution should be used when evaluating the expression as it may throw
* exceptions. In particular, code generators must ensure that generated
* code will compile in the presence of an expression that can throw
* checked exceptions.
*
* Example results are:
*
* - Primitive expresssion:
2
* - Class constructor:
new java.awt.Color(127,127,34)
* - Static field:
java.awt.Color.orange
* - Static method:
javax.swing.Box.createRigidArea(new
* java.awt.Dimension(0, 5))
*
*
* @return a fragment of Java code representing an initializer for the
* current value. It should not contain a semi-colon
* (';') to end the expression.
*/
String getJavaInitializationString();
//----------------------------------------------------------------------
/**
* Gets the property value as text.
*
* @return The property value as a human editable string.
* Returns null if the value can't be expressed as an editable string.
*
If a non-null value is returned, then the PropertyEditor should
* be prepared to parse that string back in setAsText().
*/
String getAsText();
/**
* Set the property value by parsing a given String. May raise
* java.lang.IllegalArgumentException if either the String is
* badly formatted or if this kind of property can't be expressed
* as text.
* @param text The string to be parsed.
*/
void setAsText(String text) throws java.lang.IllegalArgumentException;
//----------------------------------------------------------------------
/**
* If the property value must be one of a set of known tagged values,
* then this method should return an array of the tags. This can
* be used to represent (for example) enum values. If a PropertyEditor
* supports tags, then it should support the use of setAsText with
* a tag value as a way of setting the value and the use of getAsText
* to identify the current value.
*
* @return The tag values for this property. May be null if this
* property cannot be represented as a tagged value.
*
*/
String[] getTags();
//----------------------------------------------------------------------
/**
* A PropertyEditor may choose to make available a full custom Component
* that edits its property value. It is the responsibility of the
* PropertyEditor to hook itself up to its editor Component itself and
* to report property value changes by firing a PropertyChange event.
*
* The higher-level code that calls getCustomEditor may either embed
* the Component in some larger property sheet, or it may put it in
* its own individual dialog, or ...
*
* @return A java.awt.Component that will allow a human to directly
* edit the current property value. May be null if this is
* not supported.
*/
java.awt.Component getCustomEditor();
/**
* Determines whether this property editor supports a custom editor.
*
* @return True if the propertyEditor can provide a custom editor.
*/
boolean supportsCustomEditor();
//----------------------------------------------------------------------
/**
* Adds a listener for the value change.
* When the property editor changes its value
* it should fire a {@link PropertyChangeEvent}
* on all registered {@link PropertyChangeListener}s,
* specifying the {@code null} value for the property name
* and itself as the source.
*
* @param listener the {@link PropertyChangeListener} to add
*/
void addPropertyChangeListener(PropertyChangeListener listener);
/**
* Removes a listener for the value change.
*
* @param listener the {@link PropertyChangeListener} to remove
*/
void removePropertyChangeListener(PropertyChangeListener listener);
}