me.tfeng.toolbox.spring.ApplicationManager Maven / Gradle / Ivy

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/**
 * Copyright 2015 Thomas Feng
 *
 * Licensed to the Apache Software Foundation (ASF) under one
 * or more contributor license agreements.  See the NOTICE file
 * distributed with this work for additional information
 * regarding copyright ownership.  The ASF licenses this file
 * to you 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 me.tfeng.toolbox.spring;

import java.util.Collections;
import java.util.Comparator;
import java.util.List;
import java.util.ListIterator;
import java.util.Map.Entry;
import java.util.Set;
import java.util.stream.Collectors;

import org.apache.commons.lang3.ArrayUtils;
import org.springframework.beans.BeansException;
import org.springframework.beans.factory.config.BeanDefinition;
import org.springframework.beans.factory.support.BeanDefinitionRegistry;
import org.springframework.context.ApplicationContext;
import org.springframework.context.ApplicationContextAware;

import com.google.common.collect.ImmutableList;

import me.tfeng.toolbox.common.DependencyUtils;

/**
 * @author Thomas Feng ([email protected])
 */
public class ApplicationManager implements ApplicationContextAware {

  private static class DependencyComparator implements Comparator> {

    private final BeanDefinitionRegistry registry;

    DependencyComparator(BeanDefinitionRegistry registry) {
      this.registry = registry;
    }

    @Override
    public int compare(Entry bean1, Entry bean2) {
      String beanName1 = bean1.getKey();
      String beanName2 = bean2.getKey();
      BeanDefinition beanDefinition1 = registry.getBeanDefinition(beanName1);
      BeanDefinition beanDefinition2 = registry.getBeanDefinition(beanName2);
      if (beanDefinition1 == null || beanDefinition2 == null) {
        return 0;
      } else if (ArrayUtils.contains(beanDefinition1.getDependsOn(), beanName2)) {
        return 1;
      } else if (ArrayUtils.contains(beanDefinition2.getDependsOn(), beanName1)) {
        return -1;
      } else {
        return beanName1.compareTo(beanName2);
      }
    }
  }

  private ApplicationContext applicationContext;

  private List startableInterceptors = ImmutableList.of(new LoggingStartableInterceptor());

  private List startables;

  public ApplicationContext getApplicationContext() {
    return applicationContext;
  }

  public  T getBean(Class type) {
    return getApplicationContext().getBean(type);
  }

  public  T getBean(String name, Class type) {
    return getApplicationContext().getBean(name, type);
  }

  @Override
  public void setApplicationContext(ApplicationContext applicationContext) throws BeansException {
    this.applicationContext = applicationContext;
  }

  public void setStartableInterceptors(List startableInterceptors) {
    this.startableInterceptors = startableInterceptors;
  }

  public void start() {
    startables = findStartables();

    startables.stream().filter(startable -> startable instanceof ExtendedStartable).forEach(startable ->
        ((ExtendedStartable) startable).beforeStart());

    startables.stream().forEach(startable -> {
      startableInterceptors.stream().forEach(interceptor -> interceptor.beginStart(startable));
      try {
        startable.onStart();
        startableInterceptors.stream().forEach(interceptor -> interceptor.endStart(startable));
      } catch (Throwable t) {
        startableInterceptors.stream().forEach(interceptor -> interceptor.failStart(startable, t));
      }
    });

    startables.stream().filter(startable -> startable instanceof ExtendedStartable).forEach(startable ->
        ((ExtendedStartable) startable).afterStart());
  }

  public void stop() {
    for (ListIterator iterator = startables.listIterator(startables.size()); iterator.hasPrevious();) {
      Startable startable = iterator.previous();
      if (startable instanceof ExtendedStartable) {
        ((ExtendedStartable) startable).beforeStop();
      }
    }

    for (ListIterator iterator = startables.listIterator(startables.size()); iterator.hasPrevious();) {
      Startable startable = iterator.previous();
      startableInterceptors.stream().forEach(interceptor -> interceptor.beginStop(startable));
      try {
        startable.onStop();
        startableInterceptors.stream().forEach(interceptor -> interceptor.beginStop(startable));
      } catch (Throwable t) {
        startableInterceptors.stream().forEach(interceptor -> interceptor.failStop(startable, t));
      }
    }

    for (ListIterator iterator = startables.listIterator(startables.size()); iterator.hasPrevious();) {
      Startable startable = iterator.previous();
      if (startable instanceof ExtendedStartable) {
        ((ExtendedStartable) startable).afterStop();
      }
    }
  }

  protected List findStartables() {
    BeanDefinitionRegistry registry = (BeanDefinitionRegistry) getApplicationContext().getAutowireCapableBeanFactory();
    Set> entries = getApplicationContext().getBeansOfType(Startable.class).entrySet();
    List> sortedEntries =
        DependencyUtils.dependencySort(entries, new DependencyComparator(registry));
    return Collections.unmodifiableList(sortedEntries.stream().map(Entry::getValue).collect(Collectors.toList()));
  }
}