org.objenesis.tck.search.SearchWorkingInstantiator Maven / Gradle / Ivy

Go to download
/*
 * Copyright 2006-2024 the original author or authors.
 *
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 *     http://www.apache.org/licenses/LICENSE-2.0
 *
 * 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.
 */
package org.objenesis.tck.search;

import org.objenesis.instantiator.ObjectInstantiator;
import org.objenesis.strategy.PlatformDescription;
import org.objenesis.tck.candidates.SerializableNoConstructor;

import java.io.Serializable;
import java.lang.reflect.Constructor;
import java.lang.reflect.InvocationTargetException;
import java.lang.reflect.Modifier;
import java.util.SortedSet;

/**
 * This class will try every available instantiator on the platform to see which works.
 *
 * @author Henri Tremblay
 */
public class SearchWorkingInstantiator implements Serializable { // implements Serializable just for the test

    private final SearchWorkingInstantiatorListener listener;

    public static void main(String[] args) {
        System.out.println();
        System.out.println(PlatformDescription.describePlatform());
        System.out.println();

        SearchWorkingInstantiator searchWorkingInstantiator = new SearchWorkingInstantiator(new SystemOutListener());
        searchWorkingInstantiator.searchForInstantiator(SerializableNoConstructor.class);
    }

    public SearchWorkingInstantiator(SearchWorkingInstantiatorListener listener) {
        this.listener = listener;
    }

    public void searchForInstantiator(Class toInstantiate) {
        SortedSet classes = ClassEnumerator.getClassesForPackage(ObjectInstantiator.class.getPackage());

       for (String className : classes) {
          // Skip if inner class or isn't named like a instantiator
          if (className.contains("$") || !className.endsWith("Instantiator")) {
             continue;
          }

          Class c;
          try {
             c = Class.forName(className);
          } catch (Exception e) {
             listener.instantiatorNotFound(className, e);
             continue;
          }

          if (c.isInterface() || Modifier.isAbstract(c.getModifiers()) || !ObjectInstantiator.class.isAssignableFrom(c)) {
             continue;
          }

          Constructor constructor;
          try {
             constructor = c.getConstructor(Class.class);
          } catch (NoSuchMethodException e) {
             throw new RuntimeException(e);
          }

          try {
             ObjectInstantiator instantiator =
                (ObjectInstantiator) constructor.newInstance(toInstantiate);
             instantiator.newInstance();
             listener.instantiatorSupported(c);
          } catch (Exception e) {
             Throwable t = (e instanceof InvocationTargetException) ? e.getCause() : e;
             listener.instantiatorUnsupported(c, t);
          }
       }
    }
}