spring启动后保证创建的对象不被垃圾回收器回收

public class SimpleJndiBeanFactory extends JndiLocatorSupport implements BeanFactory {
  private final Set<String> shareableResources = new HashSet();
  //使用new创建的map，是栈中引用的对象，可作为GC Roots 对象
  private final Map<String, Object> singletonObjects = new HashMap();
  private final Map<String, Class<?>> resourceTypes = new HashMap();
  public SimpleJndiBeanFactory() {
    this.setResourceRef(true);
  }
  public void addShareableResource(String shareableResource) {
    this.shareableResources.add(shareableResource);
  }
  public void setShareableResources(String... shareableResources) {
    this.shareableResources.addAll(Arrays.asList(shareableResources));
  }
  public Object getBean(String name) throws BeansException {
    return this.getBean(name, Object.class);
  }
}

public class StaticListableBeanFactory implements ListableBeanFactory {
  private final Map<String, Object> beans;
  public StaticListableBeanFactory() {
    //使用new创建的map，是栈中引用的对象，可作为GC Roots 对象
    this.beans = new LinkedHashMap();
  }
  public StaticListableBeanFactory(Map<String, Object> beans) {
    Assert.notNull(beans, "Beans Map must not be null");
    this.beans = beans;
  }
  public void addBean(String name, Object bean) {
    this.beans.put(name, bean);
  }
}