| /* |
| * 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.cf.code; |
| |
| import com.android.dx.util.IntList; |
| import com.android.dx.util.MutabilityControl; |
| |
| /** |
| * List of (value, target) mappings representing the choices of a |
| * {@code tableswitch} or {@code lookupswitch} instruction. It |
| * also holds the default target for the switch. |
| */ |
| public final class SwitchList extends MutabilityControl { |
| /** {@code non-null;} list of test values */ |
| private final IntList values; |
| |
| /** |
| * {@code non-null;} list of targets corresponding to the test values; there |
| * is always one extra element in the target list, to hold the |
| * default target |
| */ |
| private final IntList targets; |
| |
| /** ultimate size of the list */ |
| private int size; |
| |
| /** |
| * Constructs an instance. |
| * |
| * @param size {@code >= 0;} the number of elements to be in the table |
| */ |
| public SwitchList(int size) { |
| super(true); |
| this.values = new IntList(size); |
| this.targets = new IntList(size + 1); |
| this.size = size; |
| } |
| |
| /** {@inheritDoc} */ |
| @Override |
| public void setImmutable() { |
| values.setImmutable(); |
| targets.setImmutable(); |
| super.setImmutable(); |
| } |
| |
| /** |
| * Gets the size of the list. |
| * |
| * @return {@code >= 0;} the list size |
| */ |
| public int size() { |
| return size; |
| } |
| |
| /** |
| * Gets the indicated test value. |
| * |
| * @param n {@code >= 0;}, < size(); which index |
| * @return the test value |
| */ |
| public int getValue(int n) { |
| return values.get(n); |
| } |
| |
| /** |
| * Gets the indicated target. Asking for the target at {@code size()} |
| * returns the default target. |
| * |
| * @param n {@code >= 0, <= size();} which index |
| * @return {@code >= 0;} the target |
| */ |
| public int getTarget(int n) { |
| return targets.get(n); |
| } |
| |
| /** |
| * Gets the default target. This is just a shorthand for |
| * {@code getTarget(size())}. |
| * |
| * @return {@code >= 0;} the default target |
| */ |
| public int getDefaultTarget() { |
| return targets.get(size); |
| } |
| |
| /** |
| * Gets the list of all targets. This includes one extra element at the |
| * end of the list, which holds the default target. |
| * |
| * @return {@code non-null;} the target list |
| */ |
| public IntList getTargets() { |
| return targets; |
| } |
| |
| /** |
| * Gets the list of all case values. |
| * |
| * @return {@code non-null;} the case value list |
| */ |
| public IntList getValues() { |
| return values; |
| } |
| |
| /** |
| * Sets the default target. It is only valid to call this method |
| * when all the non-default elements have been set. |
| * |
| * @param target {@code >= 0;} the absolute (not relative) default target |
| * address |
| */ |
| public void setDefaultTarget(int target) { |
| throwIfImmutable(); |
| |
| if (target < 0) { |
| throw new IllegalArgumentException("target < 0"); |
| } |
| |
| if (targets.size() != size) { |
| throw new RuntimeException("non-default elements not all set"); |
| } |
| |
| targets.add(target); |
| } |
| |
| /** |
| * Adds the given item. |
| * |
| * @param value the test value |
| * @param target {@code >= 0;} the absolute (not relative) target address |
| */ |
| public void add(int value, int target) { |
| throwIfImmutable(); |
| |
| if (target < 0) { |
| throw new IllegalArgumentException("target < 0"); |
| } |
| |
| values.add(value); |
| targets.add(target); |
| } |
| |
| /** |
| * Shrinks this instance if possible, removing test elements that |
| * refer to the default target. This is only valid after the instance |
| * is fully populated, including the default target (naturally). |
| */ |
| public void removeSuperfluousDefaults() { |
| throwIfImmutable(); |
| |
| int sz = size; |
| |
| if (sz != (targets.size() - 1)) { |
| throw new IllegalArgumentException("incomplete instance"); |
| } |
| |
| int defaultTarget = targets.get(sz); |
| int at = 0; |
| |
| for (int i = 0; i < sz; i++) { |
| int target = targets.get(i); |
| if (target != defaultTarget) { |
| if (i != at) { |
| targets.set(at, target); |
| values.set(at, values.get(i)); |
| } |
| at++; |
| } |
| } |
| |
| if (at != sz) { |
| values.shrink(at); |
| targets.set(at, defaultTarget); |
| targets.shrink(at + 1); |
| size = at; |
| } |
| } |
| } |