listorderedmap.java

iBATIS似乎已远离众说纷纭的OR框架之列

    }
    
    /**
     * Gets the index of the specified key.
     * 
     * @param key  the key to find the index of
     * @return the index, or -1 if not found
     */
    public int indexOf(Object key) {
        return insertOrder.indexOf(key);
    }

    /**
     * Sets the value at the specified index.
     *
     * @param index  the index of the value to set
     * @return the previous value at that index
     * @throws IndexOutOfBoundsException if the index is invalid
     * @since Commons Collections 3.2
     */
    public Object setValue(int index, Object value) {
        Object key = insertOrder.get(index);
        return put(key, value);
    }

    /**
     * Puts a key-value mapping into the map at the specified index.
     * <p>
     * If the map already contains the key, then the original mapping
     * is removed and the new mapping added at the specified index.
     * The remove may change the effect of the index. The index is
     * always calculated relative to the original state of the map.
     * <p>
     * Thus the steps are: (1) remove the existing key-value mapping,
     * then (2) insert the new key-value mapping at the position it
     * would have been inserted had the remove not ocurred.
     *
     * @param index  the index at which the mapping should be inserted
     * @param key  the key
     * @param value  the value
     * @return the value previously mapped to the key
     * @throws IndexOutOfBoundsException if the index is out of range
     * @since Commons Collections 3.2
     */
    public Object put(int index, Object key, Object value) {
        Map m = getMap();
        if (m.containsKey(key)) {
            Object result = m.remove(key);
            int pos = insertOrder.indexOf(key);
            insertOrder.remove(pos);
            if (pos < index) {
                index--;
            }
            insertOrder.add(index, key);
            m.put(key, value);
            return result;
        } else {
            insertOrder.add(index, key);
            m.put(key, value);
            return null;
        }
    }

    /**
     * Removes the element at the specified index.
     *
     * @param index  the index of the object to remove
     * @return the removed value, or <code>null</code> if none existed
     * @throws IndexOutOfBoundsException if the index is invalid
     */
    public Object remove(int index) {
        return remove(get(index));
    }

    /**
     * Gets an unmodifiable List view of the keys which changes as the map changes.
     * <p>
     * The returned list is unmodifiable because changes to the values of
     * the list (using {@link java.util.ListIterator#set(Object)}) will
     * effectively remove the value from the list and reinsert that value at
     * the end of the list, which is an unexpected side effect of changing the
     * value of a list.  This occurs because changing the key, changes when the
     * mapping is added to the map and thus where it appears in the list.
     * <p>
     * An alternative to this method is to use the better named
     * {@link #keyList()} or {@link #keySet()}.
     *
     * @see #keyList()
     * @see #keySet()
     * @return The ordered list of keys.  
     */
    public List asList() {
        return keyList();
    }

    //-----------------------------------------------------------------------
    static class ValuesView extends AbstractList {
        private final ListOrderedMap parent;

        ValuesView(ListOrderedMap parent) {
            super();
            this.parent = parent;
        }

        public int size() {
            return this.parent.size();
        }

        public boolean contains(Object value) {
            return this.parent.containsValue(value);
        }

        public void clear() {
            this.parent.clear();
        }

        public Iterator iterator() {
            return new AbstractIteratorDecorator(parent.entrySet().iterator()) {
                public Object next() {
                    return ((Map.Entry) iterator.next()).getValue();
                }
            };
        }

        public Object get(int index) {
            return this.parent.getValue(index);
        }

        public Object set(int index, Object value) {
            return this.parent.setValue(index, value);
        }

        public Object remove(int index) {
            return this.parent.remove(index);
        }
    }

    //-----------------------------------------------------------------------
    static class KeySetView extends AbstractSet {
        private final ListOrderedMap parent;

        KeySetView(ListOrderedMap parent) {
            super();
            this.parent = parent;
        }

        public int size() {
            return this.parent.size();
        }

        public boolean contains(Object value) {
            return this.parent.containsKey(value);
        }

        public void clear() {
            this.parent.clear();
        }

        public Iterator iterator() {
            return new AbstractIteratorDecorator(parent.entrySet().iterator()) {
                public Object next() {
                    return ((Map.Entry) super.next()).getKey();
                }
            };
        }
    }

    //-----------------------------------------------------------------------    
    static class EntrySetView extends AbstractSet {
        private final ListOrderedMap parent;
        private final List insertOrder;
        private Set entrySet;

        public EntrySetView(ListOrderedMap parent, List insertOrder) {
            super();
            this.parent = parent;
            this.insertOrder = insertOrder;
        }

        private Set getEntrySet() {
            if (entrySet == null) {
                entrySet = parent.getMap().entrySet();
            }
            return entrySet;
        }
        
        public int size() {
            return this.parent.size();
        }
        public boolean isEmpty() {
            return this.parent.isEmpty();
        }

        public boolean contains(Object obj) {
            return getEntrySet().contains(obj);
        }

        public boolean containsAll(Collection coll) {
            return getEntrySet().containsAll(coll);
        }

        public boolean remove(Object obj) {
            if (obj instanceof Map.Entry == false) {
                return false;
            }
            if (getEntrySet().contains(obj)) {
                Object key = ((Map.Entry) obj).getKey();
                parent.remove(key);
                return true;
            }
            return false;
        }

        public void clear() {
            this.parent.clear();
        }
        
        public boolean equals(Object obj) {
            if (obj == this) {
                return true;
            }
            return getEntrySet().equals(obj);
        }
        
        public int hashCode() {
            return getEntrySet().hashCode();
        }

        public String toString() {
            return getEntrySet().toString();
        }
        
        public Iterator iterator() {
            return new ListOrderedIterator(parent, insertOrder);
        }
    }
    
    //-----------------------------------------------------------------------
    static class ListOrderedIterator extends AbstractIteratorDecorator {
        private final ListOrderedMap parent;
        private Object last = null;
        
        ListOrderedIterator(ListOrderedMap parent, List insertOrder) {
            super(insertOrder.iterator());
            this.parent = parent;
        }
        
        public Object next() {
            last = super.next();
            return new ListOrderedMapEntry(parent, last);
        }

        public void remove() {
            super.remove();
            parent.getMap().remove(last);
        }
    }
    
    //-----------------------------------------------------------------------
    static class ListOrderedMapEntry extends AbstractMapEntry {
        private final ListOrderedMap parent;
        
        ListOrderedMapEntry(ListOrderedMap parent, Object key) {
            super(key, null);
            this.parent = parent;
        }
        
        public Object getValue() {
            return parent.get(key);
        }

        public Object setValue(Object value) {
            return parent.getMap().put(key, value);
        }
    }

    //-----------------------------------------------------------------------
    static class ListOrderedMapIterator implements OrderedMapIterator, ResettableIterator {
        private final ListOrderedMap parent;
        private ListIterator iterator;
        private Object last = null;
        private boolean readable = false;
        
        ListOrderedMapIterator(ListOrderedMap parent) {
            super();
            this.parent = parent;
            this.iterator = parent.insertOrder.listIterator();
        }
        
        public boolean hasNext() {
            return iterator.hasNext();
        }
        
        public Object next() {
            last = iterator.next();
            readable = true;
            return last;
        }
        
        public boolean hasPrevious() {
            return iterator.hasPrevious();
        }
        
        public Object previous() {
            last = iterator.previous();
            readable = true;
            return last;
        }
        
        public void remove() {
            if (readable == false) {
                throw new IllegalStateException(AbstractHashedMap.REMOVE_INVALID);
            }
            iterator.remove();
            parent.map.remove(last);
            readable = false;
        }
        
        public Object getKey() {
            if (readable == false) {
                throw new IllegalStateException(AbstractHashedMap.GETKEY_INVALID);
            }
            return last;
        }

        public Object getValue() {
            if (readable == false) {
                throw new IllegalStateException(AbstractHashedMap.GETVALUE_INVALID);
            }
            return parent.get(last);
        }
        
        public Object setValue(Object value) {
            if (readable == false) {
                throw new IllegalStateException(AbstractHashedMap.SETVALUE_INVALID);
            }
            return parent.map.put(last, value);
        }
        
        public void reset() {
            iterator = parent.insertOrder.listIterator();
            last = null;
            readable = false;
        }
        
        public String toString() {
            if (readable == true) {
                return "Iterator[" + getKey() + "=" + getValue() + "]";
            } else {
                return "Iterator[]";
            }
        }
    }
    
}