multikeymap.java

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     * 
     * @param key1  the first key
     * @param key2  the second key
     * @param key3  the third key
     * @param key4  the fourth key
     * @param key5  the fifth key
     * @return the value mapped to the removed key, null if key not in map
     */
    public Object remove(Object key1, Object key2, Object key3, Object key4, Object key5) {
        int hashCode = hash(key1, key2, key3, key4, key5);
        int index = map.hashIndex(hashCode, map.data.length);
        AbstractHashedMap.HashEntry entry = map.data[index];
        AbstractHashedMap.HashEntry previous = null;
        while (entry != null) {
            if (entry.hashCode == hashCode && isEqualKey(entry, key1, key2, key3, key4, key5)) {
                Object oldValue = entry.getValue();
                map.removeMapping(entry, index, previous);
                return oldValue;
            }
            previous = entry;
            entry = entry.next;
        }
        return null;
    }

    /**
     * Gets the hash code for the specified multi-key.
     * 
     * @param key1  the first key
     * @param key2  the second key
     * @param key3  the third key
     * @param key4  the fourth key
     * @param key5  the fifth key
     * @return the hash code
     */
    protected int hash(Object key1, Object key2, Object key3, Object key4, Object key5) {
        int h = 0;
        if (key1 != null) {
            h ^= key1.hashCode();
        }
        if (key2 != null) {
            h ^= key2.hashCode();
        }
        if (key3 != null) {
            h ^= key3.hashCode();
        }
        if (key4 != null) {
            h ^= key4.hashCode();
        }
        if (key5 != null) {
            h ^= key5.hashCode();
        }
        h += ~(h << 9);
        h ^=  (h >>> 14);
        h +=  (h << 4);
        h ^=  (h >>> 10);
        return h;
    }

    /**
     * Is the key equal to the combined key.
     * 
     * @param entry  the entry to compare to
     * @param key1  the first key
     * @param key2  the second key
     * @param key3  the third key
     * @param key4  the fourth key
     * @param key5  the fifth key
     * @return true if the key matches
     */
    protected boolean isEqualKey(AbstractHashedMap.HashEntry entry, Object key1, Object key2, Object key3, Object key4, Object key5) {
        MultiKey multi = (MultiKey) entry.getKey();
        return
            multi.size() == 5 &&
            (key1 == null ? multi.getKey(0) == null : key1.equals(multi.getKey(0))) &&
            (key2 == null ? multi.getKey(1) == null : key2.equals(multi.getKey(1))) &&
            (key3 == null ? multi.getKey(2) == null : key3.equals(multi.getKey(2))) &&
            (key4 == null ? multi.getKey(3) == null : key4.equals(multi.getKey(3))) &&
            (key5 == null ? multi.getKey(4) == null : key5.equals(multi.getKey(4)));
    }

    //-----------------------------------------------------------------------
    /**
     * Removes all mappings where the first key is that specified.
     * <p>
     * This method removes all the mappings where the <code>MultiKey</code>
     * has one or more keys, and the first matches that specified.
     * 
     * @param key1  the first key
     * @return true if any elements were removed
     */
    public boolean removeAll(Object key1) {
        boolean modified = false;
        MapIterator it = mapIterator();
        while (it.hasNext()) {
            MultiKey multi = (MultiKey) it.next();
            if (multi.size() >= 1 &&
                (key1 == null ? multi.getKey(0) == null : key1.equals(multi.getKey(0)))) {
                it.remove();
                modified = true;
            }
        }
        return modified;
    }

    /**
     * Removes all mappings where the first two keys are those specified.
     * <p>
     * This method removes all the mappings where the <code>MultiKey</code>
     * has two or more keys, and the first two match those specified.
     * 
     * @param key1  the first key
     * @param key2  the second key
     * @return true if any elements were removed
     */
    public boolean removeAll(Object key1, Object key2) {
        boolean modified = false;
        MapIterator it = mapIterator();
        while (it.hasNext()) {
            MultiKey multi = (MultiKey) it.next();
            if (multi.size() >= 2 &&
                (key1 == null ? multi.getKey(0) == null : key1.equals(multi.getKey(0))) &&
                (key2 == null ? multi.getKey(1) == null : key2.equals(multi.getKey(1)))) {
                it.remove();
                modified = true;
            }
        }
        return modified;
    }

    /**
     * Removes all mappings where the first three keys are those specified.
     * <p>
     * This method removes all the mappings where the <code>MultiKey</code>
     * has three or more keys, and the first three match those specified.
     * 
     * @param key1  the first key
     * @param key2  the second key
     * @param key3  the third key
     * @return true if any elements were removed
     */
    public boolean removeAll(Object key1, Object key2, Object key3) {
        boolean modified = false;
        MapIterator it = mapIterator();
        while (it.hasNext()) {
            MultiKey multi = (MultiKey) it.next();
            if (multi.size() >= 3 &&
                (key1 == null ? multi.getKey(0) == null : key1.equals(multi.getKey(0))) &&
                (key2 == null ? multi.getKey(1) == null : key2.equals(multi.getKey(1))) &&
                (key3 == null ? multi.getKey(2) == null : key3.equals(multi.getKey(2)))) {
                it.remove();
                modified = true;
            }
        }
        return modified;
    }

    /**
     * Removes all mappings where the first four keys are those specified.
     * <p>
     * This method removes all the mappings where the <code>MultiKey</code>
     * has four or more keys, and the first four match those specified.
     * 
     * @param key1  the first key
     * @param key2  the second key
     * @param key3  the third key
     * @param key4  the fourth key
     * @return true if any elements were removed
     */
    public boolean removeAll(Object key1, Object key2, Object key3, Object key4) {
        boolean modified = false;
        MapIterator it = mapIterator();
        while (it.hasNext()) {
            MultiKey multi = (MultiKey) it.next();
            if (multi.size() >= 4 &&
                (key1 == null ? multi.getKey(0) == null : key1.equals(multi.getKey(0))) &&
                (key2 == null ? multi.getKey(1) == null : key2.equals(multi.getKey(1))) &&
                (key3 == null ? multi.getKey(2) == null : key3.equals(multi.getKey(2))) &&
                (key4 == null ? multi.getKey(3) == null : key4.equals(multi.getKey(3)))) {
                it.remove();
                modified = true;
            }
        }
        return modified;
    }

    //-----------------------------------------------------------------------
    /**
     * Check to ensure that input keys are valid MultiKey objects.
     * 
     * @param key  the key to check
     */
    protected void checkKey(Object key) {
        if (key == null) {
            throw new NullPointerException("Key must not be null");
        }
        if (key instanceof MultiKey == false) {
            throw new ClassCastException("Key must be a MultiKey");
        }
    }

    /**
     * Clones the map without cloning the keys or values.
     *
     * @return a shallow clone
     */
    public Object clone() {
        return new MultiKeyMap((AbstractHashedMap) map.clone());
    }

    /**
     * Puts the key and value into the map, where the key must be a non-null
     * MultiKey object.
     * 
     * @param key  the non-null MultiKey object
     * @param value  the value to store
     * @return the previous value for the key
     * @throws NullPointerException if the key is null
     * @throws ClassCastException if the key is not a MultiKey
     */
    public Object put(Object key, Object value) {
        checkKey(key);
        return map.put(key, value);
    }

    /**
     * Copies all of the keys and values from the specified map to this map.
     * Each key must be non-null and a MultiKey object.
     * 
     * @param mapToCopy  to this map
     * @throws NullPointerException if the mapToCopy or any key within is null
     * @throws ClassCastException if any key in mapToCopy is not a MultiKey
     */
    public void putAll(Map mapToCopy) {
        for (Iterator it = mapToCopy.keySet().iterator(); it.hasNext();) {
            Object key = it.next();
            checkKey(key);
        }
        map.putAll(mapToCopy);
    }

    //-----------------------------------------------------------------------
    public MapIterator mapIterator() {
        return map.mapIterator();
    }

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

    public boolean isEmpty() {
        return map.isEmpty();
    }

    public boolean containsKey(Object key) {
        return map.containsKey(key);
    }

    public boolean containsValue(Object value) {
        return map.containsValue(value);
    }

    public Object get(Object key) {
        return map.get(key);
    }

    public Object remove(Object key) {
        return map.remove(key);
    }

    public void clear() {
        map.clear();
    }

    public Set keySet() {
        return map.keySet();
    }

    public Collection values() {
        return map.values();
    }

    public Set entrySet() {
        return map.entrySet();
    }

    public boolean equals(Object obj) {
        if (obj == this) {
            return true;
        }
        return map.equals(obj);
    }

    public int hashCode() {
        return map.hashCode();
    }

    public String toString() {
        return map.toString();
    }

}