ASTTransformerLoader.java

package edu.udel.cis.vsl.tass.library.impl;

import java.lang.reflect.Constructor;
import java.lang.reflect.InvocationTargetException;
import java.util.LinkedHashMap;
import java.util.Map;

import edu.udel.cis.vsl.tass.ast.IF.ASTFactoryIF;
import edu.udel.cis.vsl.tass.ast.IF.ASTTransformerIF;
import edu.udel.cis.vsl.tass.ast.IF.ASTTransformerLoaderIF;
import edu.udel.cis.vsl.tass.config.RunConfiguration;
import edu.udel.cis.vsl.tass.util.Strings;
import edu.udel.cis.vsl.tass.util.TASSInternalException;

public class ASTTransformerLoader implements ASTTransformerLoaderIF {

	private ASTFactoryIF astFactory;

	private Map<String, ASTTransformerIF> astTransformerCache = new LinkedHashMap<String, ASTTransformerIF>();

	private static String classPrefix = "edu.udel.cis.vsl.tass.library.";

	private static Class<ASTFactoryIF> astFactoryClass = ASTFactoryIF.class;

	public ASTTransformerLoader(RunConfiguration configuration,
			ASTFactoryIF astFactory) {
		this.astFactory = astFactory;
	}

	@SuppressWarnings("unchecked")
	@Override
	public ASTTransformerIF getASTTransformer(String name) {
		ASTTransformerIF result = astTransformerCache.get(name);

		if (result == null) {
			String aClassName = classPrefix + name + "."
					+ Strings.capitalizeFirstLetter(name) + "ASTTransformer";

			try {
				Class<? extends ASTTransformerIF> aClass = (Class<? extends ASTTransformerIF>) Class
						.forName(aClassName);
				Constructor<? extends ASTTransformerIF> constructor = aClass
						.getConstructor(astFactoryClass);

				result = constructor.newInstance(astFactory);
			} catch (ClassNotFoundException e) {
				result = null;
			} catch (NoSuchMethodException e) {
				throw new TASSInternalException("Class " + aClassName
						+ " must provide a constructor "
						+ "that takes one argument of type ASTFactoryIF");
			} catch (IllegalArgumentException e) {
				throw new TASSInternalException(e.toString());
			} catch (InstantiationException e) {
				throw new TASSInternalException(e.toString());
			} catch (IllegalAccessException e) {
				throw new TASSInternalException(e.toString());
			} catch (InvocationTargetException e) {
				throw new TASSInternalException(e.toString());
			}
			astTransformerCache.put(name, result);
		}
		return result;
	}
}