typedhashmap.java

来自「有关编译器的编译器.」· Java 代码 · 共 170 行

/* * * * * * * * * * * * * * * * * * * * * * * * * * * * * * *
 * This file is part of SableCC.                             *
 * See the file "LICENSE" for copyright information and the  *
 * terms and conditions for copying, distribution and        *
 * modification of SableCC.                                  *
 * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * */

package org.sablecc.sablecc;

import java.util.*;

public class TypedHashMap extends HashMap
{
  private Cast keyCast;
  private Cast valueCast;
  private Set entries;

  public TypedHashMap()
  {
    super();

    keyCast = NoCast.instance;
    valueCast = NoCast.instance;
  }

  public TypedHashMap(Map map)
  {
    super();

    keyCast = NoCast.instance;
    valueCast = NoCast.instance;

    Iterator entryIter = map.entrySet().iterator();
    while (entryIter.hasNext())
    {
      Map.Entry entry = (Map.Entry) entryIter.next();
      this.put(entry.getKey(),entry.getValue());
    }

  }

  public TypedHashMap(Cast keyCast, Cast valueCast)
  {
    super();

    this.keyCast = keyCast;
    this.valueCast = valueCast;
  }

  public Object clone()
  {
    return new TypedHashMap(this, keyCast, valueCast);
  }

  public TypedHashMap(Map map, Cast keyCast, Cast valueCast)
  {
    super();

    this.keyCast = keyCast;
    this.valueCast = valueCast;

    Iterator entryIter = map.entrySet().iterator();
    while (entryIter.hasNext())
    {
      Map.Entry entry = (Map.Entry) entryIter.next();
      this.put(entry.getKey(),entry.getValue());
    }

  }

  public Cast getKeyCast()
  {
    return keyCast;
  }

  public Cast getValueCast()
  {
    return valueCast;
  }

  public Set entrySet()
  {
    if(entries == null)
    {
      entries = new EntrySet(super.entrySet());
    }

    return entries;
  }

  public Object put(Object key, Object value)
  {
    return super.put(keyCast.cast(key), valueCast.cast(value));
  }

  private class EntrySet extends AbstractSet
  {
    private Set set
      ;

    EntrySet(Set set
              )
    {
      this.set = set
                   ;
    }

    public int size()
    {
      return set.size();
    }

    public Iterator iterator()
    {
      return new EntryIterator(set.iterator());
    }
  }

  private class EntryIterator implements Iterator
  {
    private Iterator iterator;

    EntryIterator(Iterator iterator)
    {
      this.iterator = iterator;
    }

    public boolean hasNext()
    {
      return iterator.hasNext();
    }

    public Object next()
    {
      return new TypedEntry((Map.Entry) iterator.next());
    }

    public void remove
      ()
    {
      iterator.remove();
    }
  }

  private class TypedEntry implements Map.Entry
  {
    private Map.Entry entry;

    TypedEntry(Map.Entry entry)
    {
      this.entry = entry;
    }

    public Object getKey()
    {
      return entry.getKey();
    }

    public Object getValue()
    {
      return entry.getValue();
    }

    public Object setValue(Object value)
    {
      return entry.setValue(valueCast.cast(value));
    }
  }
}