storedlist.java

嵌入式数据库Berkeley DB-4.5.20源代码

            closeCursor(cursor);
            StoredIterator.close(i);
            throw handleException(e, doAutoCommit);
        }
    }

    /**
     * Returns true if this list contains the specified element.
     * This method conforms to the {@link List#contains} interface.
     *
     * @throws RuntimeExceptionWrapper if a {@link DatabaseException} is
     * thrown.
     */
    public boolean contains(Object value) {

        return containsValue(value);
    }

    /**
     * Returns the element at the specified position in this list.
     * This method conforms to the {@link List#get} interface.
     *
     * @throws RuntimeExceptionWrapper if a {@link DatabaseException} is
     * thrown.
     */
    public Object get(int index) {

        return super.get(new Long(index));
    }

    /**
     * Returns the index in this list of the first occurrence of the specified
     * element, or -1 if this list does not contain this element.
     * This method conforms to the {@link List#indexOf} interface.
     *
     * @throws RuntimeExceptionWrapper if a {@link DatabaseException} is
     * thrown.
     */
    public int indexOf(Object value) {

        return indexOf(value, true);
    }

    /**
     * Returns the index in this list of the last occurrence of the specified
     * element, or -1 if this list does not contain this element.
     * This method conforms to the {@link List#lastIndexOf} interface.
     *
     * @throws RuntimeExceptionWrapper if a {@link DatabaseException} is
     * thrown.
     */
    public int lastIndexOf(Object value) {

        return indexOf(value, false);
    }

    private int indexOf(Object value, boolean findFirst) {

        DataCursor cursor = null;
        try {
            cursor = new DataCursor(view, false);
            OperationStatus status = cursor.findValue(value, findFirst);
            return (status == OperationStatus.SUCCESS)
                    ? (cursor.getCurrentRecordNumber() - baseIndex)
                    : (-1);
        } catch (Exception e) {
            throw StoredContainer.convertException(e);
        } finally {
            closeCursor(cursor);
        }
    }

    int getIndexOffset() {

        return baseIndex;
    }

    /**
     * Returns a list iterator of the elements in this list (in proper
     * sequence).
     * The iterator will be read-only if the collection is read-only.
     * This method conforms to the {@link List#listIterator()} interface.
     *
     * <p>For information on cursor stability and iterator block size, see
     * {@link #iterator()}.</p>
     *
     * @return a {@link ListIterator} for this collection.
     *
     * @throws RuntimeExceptionWrapper if a {@link DatabaseException} is
     * thrown.
     *
     * @see #isWriteAllowed
     */
    public ListIterator listIterator() {

        return blockIterator();
    }

    /**
     * Returns a list iterator of the elements in this list (in proper
     * sequence), starting at the specified position in this list.
     * The iterator will be read-only if the collection is read-only.
     * This method conforms to the {@link List#listIterator(int)} interface.
     *
     * <p>For information on cursor stability and iterator block size, see
     * {@link #iterator()}.</p>
     *
     * @return a {@link ListIterator} for this collection.
     *
     * @throws RuntimeExceptionWrapper if a {@link DatabaseException} is
     * thrown.
     *
     * @see #isWriteAllowed
     */
    public ListIterator listIterator(int index) {

        BlockIterator i = blockIterator();
        if (i.moveToIndex(index)) {
            return i;
        } else {
            throw new IndexOutOfBoundsException(String.valueOf(index));
        }
    }

    /**
     * Removes the element at the specified position in this list (optional
     * operation).
     * This method conforms to the {@link List#remove(int)} interface.
     *
     * @throws UnsupportedOperationException if the collection is a sublist, or
     * if the collection is read-only.
     *
     * @throws RuntimeExceptionWrapper if a {@link DatabaseException} is
     * thrown.
     */
    public Object remove(int index) {

        try {
            Object[] oldVal = new Object[1];
            removeKey(new Long(index), oldVal);
            return oldVal[0];
        } catch (IllegalArgumentException e) {
            throw new IndexOutOfBoundsException(e.getMessage());
        }
    }

    /**
     * Removes the first occurrence in this list of the specified element
     * (optional operation).
     * This method conforms to the {@link List#remove(Object)} interface.
     *
     * @throws UnsupportedOperationException if the collection is a sublist, or
     * if the collection is read-only.
     *
     * @throws RuntimeExceptionWrapper if a {@link DatabaseException} is
     * thrown.
     */
    public boolean remove(Object value) {

        return removeValue(value);
    }

    /**
     * Replaces the element at the specified position in this list with the
     * specified element (optional operation).
     * This method conforms to the {@link List#set} interface.
     *
     * @throws UnsupportedOperationException if the collection is indexed, or
     * if the collection is read-only.
     *
     * @throws IllegalArgumentException if an entity value binding is used and
     * the primary key of the value given is different than the existing stored
     * primary key.
     *
     * @throws RuntimeExceptionWrapper if a {@link DatabaseException} is
     * thrown.
     */
    public Object set(int index, Object value) {

        try {
            return put(new Long(index), value);
        } catch (IllegalArgumentException e) {
            throw new IndexOutOfBoundsException(e.getMessage());
        }
    }

    /**
     * Returns a view of the portion of this list between the specified
     * fromIndex, inclusive, and toIndex, exclusive.
     * Note that add() and remove() may not be called for the returned sublist.
     * This method conforms to the {@link List#subList} interface.
     *
     * @throws RuntimeExceptionWrapper if a {@link DatabaseException} is
     * thrown.
     */
    public List subList(int fromIndex, int toIndex) {

        if (fromIndex < 0 || fromIndex > toIndex) {
            throw new IndexOutOfBoundsException(String.valueOf(fromIndex));
        }
        try {
            int newBaseIndex = baseIndex + fromIndex;
            return new StoredList(
                view.subView(new Long(fromIndex), true,
                             new Long(toIndex), false,
                             new IndexKeyBinding(newBaseIndex)),
                newBaseIndex);
        } catch (KeyRangeException e) {
            throw new IndexOutOfBoundsException(e.getMessage());
        } catch (Exception e) {
            throw StoredContainer.convertException(e);
        }
    }

    /**
     * Compares the specified object with this list for equality.
     * A value comparison is performed by this method and the stored values
     * are compared rather than calling the equals() method of each element.
     * This method conforms to the {@link List#equals} interface.
     *
     * @throws RuntimeExceptionWrapper if a {@link DatabaseException} is
     * thrown.
     */
    public boolean equals(Object other) {

        if (!(other instanceof List)) return false;
        List otherList = (List) other;
        StoredIterator i1 = null;
        ListIterator i2 = null;
        try {
            i1 = storedIterator();
            i2 = storedOrExternalListIterator(otherList);
            while (i1.hasNext()) {
                if (!i2.hasNext()) return false;
                if (i1.nextIndex() != i2.nextIndex()) return false;
                Object o1 = i1.next();
                Object o2 = i2.next();
                if (o1 == null) {
                    if (o2 != null) return false;
                } else {
                    if (!o1.equals(o2)) return false;
                }
            }
            if (i2.hasNext()) return false;
            return true;
        } finally {
            i1.close();
            StoredIterator.close(i2);
        }
    }

    /**
     * Returns a StoredIterator if the given collection is a StoredCollection,
     * else returns a regular/external ListIterator.  The iterator returned
     * should be closed with the static method StoredIterator.close(Iterator).
     */
    final ListIterator storedOrExternalListIterator(List list) {

        if (list instanceof StoredCollection) {
            return ((StoredCollection) list).storedIterator();
        } else {
            return list.listIterator();
        }
    }

    /*
     * Add this in to keep FindBugs from whining at us about implementing
     * equals(), but not hashCode().
     */
    public int hashCode() {
	return super.hashCode();
    }

    Object makeIteratorData(BaseIterator iterator,
                            DatabaseEntry keyEntry,
                            DatabaseEntry priKeyEntry,
                            DatabaseEntry valueEntry) {

        return view.makeValue(priKeyEntry, valueEntry);
    }

    boolean hasValues() {

        return true;
    }

    private static class IndexKeyBinding extends RecordNumberBinding {

        private int baseIndex;

        private IndexKeyBinding(int baseIndex) {

            this.baseIndex = baseIndex;
        }

        public Object entryToObject(DatabaseEntry data) {

            return new Long(entryToRecordNumber(data) - baseIndex);
        }

        public void objectToEntry(Object object, DatabaseEntry data) {

            recordNumberToEntry(((Number) object).intValue() + baseIndex,
                                data);
        }
    }
}