1/*
2 * Copyright (C) 2007 The Android Open Source Project
3 *
4 * Licensed under the Apache License, Version 2.0 (the "License");
5 * you may not use this file except in compliance with the License.
6 * You may obtain a copy of the License at
7 *
8 *      http://www.apache.org/licenses/LICENSE-2.0
9 *
10 * Unless required by applicable law or agreed to in writing, software
11 * distributed under the License is distributed on an "AS IS" BASIS,
12 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
13 * See the License for the specific language governing permissions and
14 * limitations under the License.
15 */
16
17package com.android.dx.rop.type;
18
19/**
20 * List of {@link Type} instances (or of things that contain types).
21 */
22public interface TypeList {
23    /**
24     * Returns whether this instance is mutable. Note that the
25     * {@code TypeList} interface itself doesn't provide any
26     * means of mutation, but that doesn't mean that there isn't an
27     * extra-interface way of mutating an instance.
28     *
29     * @return {@code true} if this instance is mutable or
30     * {@code false} if it is immutable
31     */
32    public boolean isMutable();
33
34    /**
35     * Gets the size of this list.
36     *
37     * @return {@code >= 0;} the size
38     */
39    public int size();
40
41    /**
42     * Gets the indicated element. It is an error to call this with the
43     * index for an element which was never set; if you do that, this
44     * will throw {@code NullPointerException}.
45     *
46     * @param n {@code >= 0, < size();} which element
47     * @return {@code non-null;} the indicated element
48     */
49    public Type getType(int n);
50
51    /**
52     * Gets the number of 32-bit words required to hold instances of
53     * all the elements of this list. This is a sum of the widths (categories)
54     * of all the elements.
55     *
56     * @return {@code >= 0;} the required number of words
57     */
58    public int getWordCount();
59
60    /**
61     * Returns a new instance which is identical to this one, except that
62     * the given item is appended to the end and it is guaranteed to be
63     * immutable.
64     *
65     * @param type {@code non-null;} item to append
66     * @return {@code non-null;} an appropriately-constructed instance
67     */
68    public TypeList withAddedType(Type type);
69}
70