1579d7739c53a2707ad711a2d2cae46d7d782f06Jesse Wilson/* 2579d7739c53a2707ad711a2d2cae46d7d782f06Jesse Wilson * Copyright (C) 2007 The Android Open Source Project 3579d7739c53a2707ad711a2d2cae46d7d782f06Jesse Wilson * 4579d7739c53a2707ad711a2d2cae46d7d782f06Jesse Wilson * Licensed under the Apache License, Version 2.0 (the "License"); 5579d7739c53a2707ad711a2d2cae46d7d782f06Jesse Wilson * you may not use this file except in compliance with the License. 6579d7739c53a2707ad711a2d2cae46d7d782f06Jesse Wilson * You may obtain a copy of the License at 7579d7739c53a2707ad711a2d2cae46d7d782f06Jesse Wilson * 8579d7739c53a2707ad711a2d2cae46d7d782f06Jesse Wilson * http://www.apache.org/licenses/LICENSE-2.0 9579d7739c53a2707ad711a2d2cae46d7d782f06Jesse Wilson * 10579d7739c53a2707ad711a2d2cae46d7d782f06Jesse Wilson * Unless required by applicable law or agreed to in writing, software 11579d7739c53a2707ad711a2d2cae46d7d782f06Jesse Wilson * distributed under the License is distributed on an "AS IS" BASIS, 12579d7739c53a2707ad711a2d2cae46d7d782f06Jesse Wilson * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. 13579d7739c53a2707ad711a2d2cae46d7d782f06Jesse Wilson * See the License for the specific language governing permissions and 14579d7739c53a2707ad711a2d2cae46d7d782f06Jesse Wilson * limitations under the License. 15579d7739c53a2707ad711a2d2cae46d7d782f06Jesse Wilson */ 16579d7739c53a2707ad711a2d2cae46d7d782f06Jesse Wilson 17579d7739c53a2707ad711a2d2cae46d7d782f06Jesse Wilsonpackage com.android.dx.rop.cst; 18579d7739c53a2707ad711a2d2cae46d7d782f06Jesse Wilson 19579d7739c53a2707ad711a2d2cae46d7d782f06Jesse Wilson/** 20579d7739c53a2707ad711a2d2cae46d7d782f06Jesse Wilson * Interface for constant pools, which are, more or less, just lists of 21579d7739c53a2707ad711a2d2cae46d7d782f06Jesse Wilson * {@link Constant} objects. 22579d7739c53a2707ad711a2d2cae46d7d782f06Jesse Wilson */ 23579d7739c53a2707ad711a2d2cae46d7d782f06Jesse Wilsonpublic interface ConstantPool { 24579d7739c53a2707ad711a2d2cae46d7d782f06Jesse Wilson /** 25579d7739c53a2707ad711a2d2cae46d7d782f06Jesse Wilson * Get the "size" of the constant pool. This corresponds to the 26579d7739c53a2707ad711a2d2cae46d7d782f06Jesse Wilson * class file field {@code constant_pool_count}, and is in fact 27579d7739c53a2707ad711a2d2cae46d7d782f06Jesse Wilson * always at least one more than the actual size of the constant pool, 28579d7739c53a2707ad711a2d2cae46d7d782f06Jesse Wilson * as element {@code 0} is always invalid. 29579d7739c53a2707ad711a2d2cae46d7d782f06Jesse Wilson * 30579d7739c53a2707ad711a2d2cae46d7d782f06Jesse Wilson * @return {@code >= 1;} the size 31579d7739c53a2707ad711a2d2cae46d7d782f06Jesse Wilson */ 32579d7739c53a2707ad711a2d2cae46d7d782f06Jesse Wilson public int size(); 33579d7739c53a2707ad711a2d2cae46d7d782f06Jesse Wilson 34579d7739c53a2707ad711a2d2cae46d7d782f06Jesse Wilson /** 35579d7739c53a2707ad711a2d2cae46d7d782f06Jesse Wilson * Get the {@code n}th entry in the constant pool, which must 36579d7739c53a2707ad711a2d2cae46d7d782f06Jesse Wilson * be valid. 37579d7739c53a2707ad711a2d2cae46d7d782f06Jesse Wilson * 38579d7739c53a2707ad711a2d2cae46d7d782f06Jesse Wilson * @param n {@code n >= 0, n < size();} the constant pool index 39579d7739c53a2707ad711a2d2cae46d7d782f06Jesse Wilson * @return {@code non-null;} the corresponding entry 40579d7739c53a2707ad711a2d2cae46d7d782f06Jesse Wilson * @throws IllegalArgumentException thrown if {@code n} is 41579d7739c53a2707ad711a2d2cae46d7d782f06Jesse Wilson * in-range but invalid 42579d7739c53a2707ad711a2d2cae46d7d782f06Jesse Wilson */ 43579d7739c53a2707ad711a2d2cae46d7d782f06Jesse Wilson public Constant get(int n); 44579d7739c53a2707ad711a2d2cae46d7d782f06Jesse Wilson 45579d7739c53a2707ad711a2d2cae46d7d782f06Jesse Wilson /** 46579d7739c53a2707ad711a2d2cae46d7d782f06Jesse Wilson * Get the {@code n}th entry in the constant pool, which must 47579d7739c53a2707ad711a2d2cae46d7d782f06Jesse Wilson * be valid unless {@code n == 0}, in which case {@code null} 48579d7739c53a2707ad711a2d2cae46d7d782f06Jesse Wilson * is returned. 49579d7739c53a2707ad711a2d2cae46d7d782f06Jesse Wilson * 50579d7739c53a2707ad711a2d2cae46d7d782f06Jesse Wilson * @param n {@code n >= 0, n < size();} the constant pool index 51579d7739c53a2707ad711a2d2cae46d7d782f06Jesse Wilson * @return {@code null-ok;} the corresponding entry, if {@code n != 0} 52579d7739c53a2707ad711a2d2cae46d7d782f06Jesse Wilson * @throws IllegalArgumentException thrown if {@code n} is 53579d7739c53a2707ad711a2d2cae46d7d782f06Jesse Wilson * in-range and non-zero but invalid 54579d7739c53a2707ad711a2d2cae46d7d782f06Jesse Wilson */ 55579d7739c53a2707ad711a2d2cae46d7d782f06Jesse Wilson public Constant get0Ok(int n); 56579d7739c53a2707ad711a2d2cae46d7d782f06Jesse Wilson 57579d7739c53a2707ad711a2d2cae46d7d782f06Jesse Wilson /** 58579d7739c53a2707ad711a2d2cae46d7d782f06Jesse Wilson * Get the {@code n}th entry in the constant pool, or 59579d7739c53a2707ad711a2d2cae46d7d782f06Jesse Wilson * {@code null} if the index is in-range but invalid. In 60579d7739c53a2707ad711a2d2cae46d7d782f06Jesse Wilson * particular, {@code null} is returned for index {@code 0} 61579d7739c53a2707ad711a2d2cae46d7d782f06Jesse Wilson * as well as the index after any entry which is defined to take up 62579d7739c53a2707ad711a2d2cae46d7d782f06Jesse Wilson * two slots (that is, {@code Long} and {@code Double} 63579d7739c53a2707ad711a2d2cae46d7d782f06Jesse Wilson * entries). 64579d7739c53a2707ad711a2d2cae46d7d782f06Jesse Wilson * 65579d7739c53a2707ad711a2d2cae46d7d782f06Jesse Wilson * @param n {@code n >= 0, n < size();} the constant pool index 66579d7739c53a2707ad711a2d2cae46d7d782f06Jesse Wilson * @return {@code null-ok;} the corresponding entry, or {@code null} if 67579d7739c53a2707ad711a2d2cae46d7d782f06Jesse Wilson * the index is in-range but invalid 68579d7739c53a2707ad711a2d2cae46d7d782f06Jesse Wilson */ 69579d7739c53a2707ad711a2d2cae46d7d782f06Jesse Wilson public Constant getOrNull(int n); 70579d7739c53a2707ad711a2d2cae46d7d782f06Jesse Wilson} 71