| /* |
| * Copyright (C) 2007 The Android Open Source Project |
| * |
| * Licensed under the Apache License, Version 2.0 (the "License"); |
| * you may not use this file except in compliance with the License. |
| * You may obtain a copy of the License at |
| * |
| * http://www.apache.org/licenses/LICENSE-2.0 |
| * |
| * Unless required by applicable law or agreed to in writing, software |
| * distributed under the License is distributed on an "AS IS" BASIS, |
| * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. |
| * See the License for the specific language governing permissions and |
| * limitations under the License. |
| */ |
| |
| package com.android.dx.rop.cst; |
| |
| /** |
| * Interface for constant pools, which are, more or less, just lists of |
| * {@link Constant} objects. |
| */ |
| public interface ConstantPool { |
| /** |
| * Get the "size" of the constant pool. This corresponds to the |
| * class file field {@code constant_pool_count}, and is in fact |
| * always at least one more than the actual size of the constant pool, |
| * as element {@code 0} is always invalid. |
| * |
| * @return {@code >= 1;} the size |
| */ |
| public int size(); |
| |
| /** |
| * Get the {@code n}th entry in the constant pool, which must |
| * be valid. |
| * |
| * @param n {@code n >= 0, n < size();} the constant pool index |
| * @return {@code non-null;} the corresponding entry |
| * @throws IllegalArgumentException thrown if {@code n} is |
| * in-range but invalid |
| */ |
| public Constant get(int n); |
| |
| /** |
| * Get the {@code n}th entry in the constant pool, which must |
| * be valid unless {@code n == 0}, in which case {@code null} |
| * is returned. |
| * |
| * @param n {@code n >= 0, n < size();} the constant pool index |
| * @return {@code null-ok;} the corresponding entry, if {@code n != 0} |
| * @throws IllegalArgumentException thrown if {@code n} is |
| * in-range and non-zero but invalid |
| */ |
| public Constant get0Ok(int n); |
| |
| /** |
| * Get the {@code n}th entry in the constant pool, or |
| * {@code null} if the index is in-range but invalid. In |
| * particular, {@code null} is returned for index {@code 0} |
| * as well as the index after any entry which is defined to take up |
| * two slots (that is, {@code Long} and {@code Double} |
| * entries). |
| * |
| * @param n {@code n >= 0, n < size();} the constant pool index |
| * @return {@code null-ok;} the corresponding entry, or {@code null} if |
| * the index is in-range but invalid |
| */ |
| public Constant getOrNull(int n); |
| } |