jcckit.util.Factory Maven / Gradle / Ivy
Go to download
Show more of this group Show more artifacts with this name
Show all versions of plantuml-gplv2 Show documentation
Show all versions of plantuml-gplv2 Show documentation
PlantUML is a component that allows to quickly write diagrams from text.
// THIS FILE HAS BEEN GENERATED BY A PREPROCESSOR.
/* +=======================================================================
* |
* | PlantUML : a free UML diagram generator
* |
* +=======================================================================
*
* (C) Copyright 2009-2024, Arnaud Roques
*
* Project Info: https://plantuml.com
*
* If you like this project or if you find it useful, you can support us at:
*
* https://plantuml.com/patreon (only 1$ per month!)
* https://plantuml.com/liberapay (only 1€ per month!)
* https://plantuml.com/paypal
*
*
* PlantUML is free software; you can redistribute it and/or modify it
* under the terms of the GNU General Public License V2.
*
* THE ACCOMPANYING PROGRAM IS PROVIDED UNDER THE TERMS OF THIS ECLIPSE PUBLIC
* LICENSE ("AGREEMENT"). [GNU General Public License V2]
*
* ANY USE, REPRODUCTION OR DISTRIBUTION OF THE PROGRAM CONSTITUTES
* RECIPIENT'S ACCEPTANCE OF THIS AGREEMENT.
*
* You may obtain a copy of the License at
*
* https://www.gnu.org/licenses/old-licenses/gpl-2.0.html
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*
* PlantUML can occasionally display sponsored or advertising messages. Those
* messages are usually generated on welcome or error images and never on
* functional diagrams.
* See https://plantuml.com/professional if you want to remove them
*
* Images (whatever their format : PNG, SVG, EPS...) generated by running PlantUML
* are owned by the author of their corresponding sources code (that is, their
* textual description in PlantUML language). Those images are not covered by
* this GPL v2 license.
*
* The generated images can then be used without any reference to the GPL v2 license.
* It is not even necessary to stipulate that they have been generated with PlantUML,
* although this will be appreciated by the PlantUML team.
*
* There is an exception : if the textual description in PlantUML language is also covered
* by any license, then the generated images are logically covered
* by the very same license.
*
* This is the IGY distribution (Install GraphViz by Yourself).
* You have to install GraphViz and to setup the GRAPHVIZ_DOT environment variable
* (see https://plantuml.com/graphviz-dot )
*
* Icons provided by OpenIconic : https://useiconic.com/open
* Archimate sprites provided by Archi : http://www.archimatetool.com
* Stdlib AWS provided by https://github.com/milo-minderbinder/AWS-PlantUML
* Stdlib Icons provided https://github.com/tupadr3/plantuml-icon-font-sprites
* ASCIIMathML (c) Peter Jipsen http://www.chapman.edu/~jipsen
* ASCIIMathML (c) David Lippman http://www.pierce.ctc.edu/dlippman
* CafeUndZopfli ported by Eugene Klyuchnikov https://github.com/eustas/CafeUndZopfli
* Brotli (c) by the Brotli Authors https://github.com/google/brotli
* Themes (c) by Brett Schwarz https://github.com/bschwarz/puml-themes
* Twemoji (c) by Twitter at https://twemoji.twitter.com/
*
*/
package jcckit.util;
import java.lang.reflect.Constructor;
/**
* General purpose factory method based on {@link ConfigParameters}
* and Java's Reflection API.
*
* @author Franz-Josef Elmer
*/
public class Factory {
/** The constant defining the key className. */
public static final String CLASS_NAME_KEY = "className";
/** No public constructor necessary. */
private Factory() {}
/**
* Creates an instance of the specified class.
* @param className Fully-qualified name of a class with a default
* constructor.
* @return a new instance.
* @throws IllegalArgumentException if the instance could be created.
*/
public static Object create(String className) {
try {
return Class.forName(className).newInstance();
} catch (Throwable t) {
throw new IllegalArgumentException("Could not create an instance of "
+ className + " because of " + t);
}
}
/**
* Creates an object based on the specified configuration
* parameters. The class of the object is determined by the
* parameter with the key {@link #CLASS_NAME_KEY}.
* The constructor with a single argument of the type
* ConfigParameter is invoked with the argument
* configParameters. If such a constructor
* does not exists the default constructor is invoked. If
* neither of these constructors exist a {@link FactoryException}
* is thrown.
* @param configParameters Configuration parameters.
* @return the newly created object.
* @throws IllegalArgumentException if key className is missing.
* @throws FactoryException wrapping any kind of exception or error occured.
*/
public static Object create(ConfigParameters configParameters) {
String className = configParameters.get(CLASS_NAME_KEY);
return createObject(configParameters, className);
}
/**
* Creates an object based on the specified configuration
* parameters and default class name. If the
* parameter with the key {@link #CLASS_NAME_KEY} is missed in
* configParameters defaultClassName is used.
* Otherwise it works as {@link #create(jcckit.util.ConfigParameters)}.
* @param configParameters Configuration parameters.
* @param defaultClassName Default class name.
* @return the newly created object.
* @throws FactoryException wrapping any kind of exception or error occured.
*/
public static Object create(ConfigParameters configParameters,
String defaultClassName) {
String className = configParameters.get(CLASS_NAME_KEY, defaultClassName);
return createObject(configParameters, className);
}
/**
* Creates an object based on the specified configuration
* parameters or returns the default object. This method behaves
* as {@link #create(jcckit.util.ConfigParameters)}, except that is does
* not throw an IllegalArgumentException if key className
* is missing. Instead defaultObject is returned.
*/
public static Object createOrGet(ConfigParameters configParameters,
Object defaultObject) {
String className = configParameters.get(CLASS_NAME_KEY, null);
return className == null ? defaultObject
: createObject(configParameters, className);
}
private static Object createObject(ConfigParameters configParameters,
String className) {
try {
Class c = Class.forName(className);
Object result = null;
Constructor constructor = null;
try {
constructor = c.getConstructor(new Class[] {ConfigParameters.class});
result = constructor.newInstance(new Object[] {configParameters});
} catch (NoSuchMethodException e) {
result = c.newInstance();
}
return result;
} catch (Throwable t) {
throw new FactoryException(configParameters, CLASS_NAME_KEY, t);
}
}
}