Prolog.java
/*
* #%L
* prolobjectlink-jpi
* %%
* Copyright (C) 2019 Prolobjectlink Project
* %%
* Permission is hereby granted, free of charge, to any person obtaining a copy
* of this software and associated documentation files (the "Software"), to deal
* in the Software without restriction, including without limitation the rights
* to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
* copies of the Software, and to permit persons to whom the Software is
* furnished to do so, subject to the following conditions:
*
* The above copyright notice and this permission notice shall be included in
* all copies or substantial portions of the Software.
*
* THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
* IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
* FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
* AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
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* OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
* THE SOFTWARE.
* #L%
*/
package io.github.prolobjectlink.prolog;
import java.lang.reflect.Constructor;
import java.util.logging.Level;
import java.util.logging.Logger;
import javax.script.ScriptEngine;
import javax.script.ScriptEngineManager;
/**
* Bootstrap platform class. Contains {@link #getProvider(Class)} method that
* return an instance of Prolog Provider from the given class. Alternatively can
* be used {@link #getProvider()} for create and return a {@link PrologProvider}
* using Java Platform discovery pattern.
*
* @author Jose Zalacain
* @since 1.0
*/
public final class Prolog {
private Prolog() {
}
/**
* Create and return an instance of Prolog Provider using Java Platform
* discovery pattern.
*
* @return an instance of Prolog Provider from the given class.
* @since 1.1
*/
public static PrologProvider getProvider() {
ScriptEngineManager manager = new ScriptEngineManager();
ScriptEngine engine = manager.getEngineByName("prolog");
return ((PrologScriptEngine) engine).getProvider();
}
/**
* Create and return an instance of Prolog Provider using the Prolog Provider
* class name.
*
* @return an instance of Prolog Provider from the given class.
* @since 1.1
*/
public static PrologProvider getProvider(String className) {
PrologProvider provider = null;
try {
return getProvider(Class.forName(className));
} catch (ClassNotFoundException e) {
Logger.getLogger(Prolog.class.getName()).log(Level.FINEST, null, e);
}
return provider;
}
/**
* Create and return an instance of Prolog Provider from the given class.
*
* @param providerClass Prolog Provider class used to create a new instance.
* @return an instance of Prolog Provider from the given class.
* @since 1.0
*/
public static PrologProvider getProvider(Class<?> providerClass) {
PrologProvider provider = null;
try {
Constructor<?> constructor = providerClass.getDeclaredConstructor();
constructor.setAccessible(true);
provider = (PrologProvider) providerClass.newInstance();
constructor.setAccessible(false);
} catch (InstantiationException e) {
Logger.getLogger(Prolog.class.getName()).log(Level.FINEST, null, e);
} catch (IllegalAccessException e) {
Logger.getLogger(Prolog.class.getName()).log(Level.FINEST, null, e);
} catch (NoSuchMethodException e) {
Logger.getLogger(Prolog.class.getName()).log(Level.FINEST, null, e);
} catch (SecurityException e) {
Logger.getLogger(Prolog.class.getName()).log(Level.FINEST, null, e);
}
return provider;
}
}