ObjectCollection.java

/*****************************************************************************
 *  Limpet - the Lightweight InforMation ProcEssing Toolkit
 *  http://limpet.info
 *
 *  (C) 2015-2016, Deep Blue C Technologies Ltd
 *
 *  This library is free software; you can redistribute it and/or
 *  modify it under the terms of the Eclipse Public License v1.0
 *  (http://www.eclipse.org/legal/epl-v10.html)
 *
 *  This library is distributed in the hope that it will be useful,
 *  but WITHOUT ANY WARRANTY; without even the implied warranty of
 *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.
 *****************************************************************************/
package info.limpet.data.impl;

import info.limpet.IChangeListener;
import info.limpet.ICommand;
import info.limpet.IObjectCollection;
import info.limpet.IStoreGroup;
import info.limpet.UIProperty;

import java.lang.reflect.ParameterizedType;
import java.lang.reflect.Type;
import java.util.ArrayList;
import java.util.Iterator;
import java.util.List;
import java.util.UUID;

public class ObjectCollection<T extends Object> implements IObjectCollection<T>
{

  private final LimpetList<T> values = new LimpetList<T>();
  private String name;
  private String description = "";
  private final ICommand<?> precedent;
  private final List<ICommand<?>> dependents;
  private transient UUID uuid;

  // note: we make the change support listeners transient, since
  // they refer to UI elements that we don't persist
  private transient ListenerHelper _changeSupport;
  private IStoreGroup parent;

  public ObjectCollection(String name)
  {
    this(name, null);
  }

  public ObjectCollection(String name, ICommand<?> precedent)
  {
    this.name = name;
    this.precedent = precedent;
    dependents = new ArrayList<ICommand<?>>();

    // setup helpers
    initListeners();
  }

  @Override
  public int hashCode()
  {
    final int prime = 31;
    int result = 1;
    result = prime * result + getUUID().hashCode();
    return result;
  }

  @Override
  public boolean equals(Object obj)
  {
    if (this == obj)
    {
      return true;
    }
    if (obj == null)
    {
      return false;
    }
    if (getClass() != obj.getClass())
    {
      return false;
    }
    ObjectCollection<?> other = (ObjectCollection<?>) obj;
    if (!getUUID().equals(other.getUUID()))
    {
      return false;
    }
    return true;
  }

  @Override
  public UUID getUUID()
  {
    if (uuid == null)
    {
      uuid = UUID.randomUUID();
    }
    return uuid;
  }

  @Override
  @UIProperty(name = "Description", category = UIProperty.CATEGORY_LABEL)
  public String getDescription()
  {
    return description;
  }

  @Override
  public void setDescription(String description)
  {
    this.description = description;

    // tell anyone that wants to know
    _changeSupport.fireMetadataChange(this);
  }

  @Override
  public List<T> getValues()
  {
    return values;
  }

  @Override
  public void add(T value)
  {
    values.add(value);
  }

  @Override
  @UIProperty(name = "Size", category = UIProperty.CATEGORY_LABEL)
  public int getValuesCount()
  {
    return values.size();
  }

  @Override
  @UIProperty(name = "Name", category = UIProperty.CATEGORY_LABEL)
  public String getName()
  {
    return name;
  }

  @Override
  public boolean isQuantity()
  {
    return false;
  }

  @Override
  public boolean isTemporal()
  {
    return false;
  }

  @Override
  public ICommand<?> getPrecedent()
  {
    return precedent;
  }

  @Override
  public List<ICommand<?>> getDependents()
  {
    return dependents;
  }

  @Override
  public void addDependent(ICommand<?> command)
  {
    dependents.add(command);
  }

  @Override
  public void setName(String name)
  {
    this.name = name;

    // tell anyone that wants to know
    _changeSupport.fireMetadataChange(this);
  }

  protected void initListeners()
  {
    if (_changeSupport == null)
    {
      _changeSupport = new ListenerHelper();
    }
  }

  @Override
  public void addChangeListener(IChangeListener listener)
  {
    initListeners();

    _changeSupport.add(listener);
  }

  @Override
  public void removeChangeListener(IChangeListener listener)
  {
    initListeners();

    _changeSupport.remove(listener);
  }

  @Override
  public IStoreGroup getParent()
  {
    return parent;
  }

  @Override
  public void setParent(IStoreGroup parent)
  {
    this.parent = parent;
  }

  @Override
  public void fireDataChanged()
  {
    if (_changeSupport != null)
    {
      // tell any standard listeners
      _changeSupport.fireDataChange(this);
    }

    // now tell the dependents
    Iterator<ICommand<?>> iter = dependents.iterator();
    while (iter.hasNext())
    {
      ICommand<?> iC = (ICommand<?>) iter.next();
      iC.dataChanged(this);
    }
  }

  @Override
  public Class<?> storedClass()
  {
    @SuppressWarnings("unchecked")
    final Class<? extends ObjectCollection<?>> thisClass =
        (Class<? extends ObjectCollection<?>>) getClass();
    final Type superType = thisClass.getGenericSuperclass();
    if (superType instanceof ParameterizedType)
    {
      final ParameterizedType parameterizedType = (ParameterizedType) superType;
      Type theItem = parameterizedType.getActualTypeArguments()[0];
      if (theItem instanceof Class<?>)
      {
        return (Class<?>) theItem;
      }
      else
      {
        return null;
      }
    }
    else
    {
      return null;
    }
  }

  @Override
  public boolean hasChildren()
  {
    return getValuesCount() > 0;
  }

  @Override
  public void beingDeleted()
  {
    if (_changeSupport != null)
    {
      // tell any standard listeners
      _changeSupport.beingDeleted(this);
    }

    // now tell the dependents
    Iterator<ICommand<?>> iter = dependents.iterator();
    while (iter.hasNext())
    {
      ICommand<?> iC = (ICommand<?>) iter.next();
      iC.collectionDeleted(this);
    }

  }

  public void fireMetadataChanged()
  {
    if (_changeSupport != null)
    {
      // tell any standard listeners
      _changeSupport.fireMetadataChange(this);
    }
  }

  @Override
  public void clear()
  {
    clearQuiet();
    fireDataChanged();
  }

  @Override
  public void clearQuiet()
  {
    values.clear();
  }

}