proguard.analysis.cpa.jvm.witness.JvmStackLocation Maven / Gradle / Ivy

Go to download

Show more of this group Show more artifacts with this name
Show all versions of proguard-core Show documentation

ProGuardCORE is a free library to read, analyze, modify, and write Java class files.

There is a newer version: 9.1.6

/*
 * ProGuardCORE -- library to process Java bytecode.
 *
 * Copyright (c) 2002-2022 Guardsquare NV
 *
 * 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 proguard.analysis.cpa.jvm.witness;

import java.util.Objects;
import proguard.analysis.cpa.defaults.LatticeAbstractState;
import proguard.analysis.cpa.jvm.state.JvmAbstractState;

/**
 * The {@link JvmStackLocation} is a memory location at the operand stack. Indexing starts from the
 * top of the stack.
 *
 * @author Dmitry Ivanov
 */
public class JvmStackLocation extends JvmMemoryLocation {

  public final int index;

  /**
   * Create a stack location.
   *
   * @param index a stack element index from the top
   */
  public JvmStackLocation(int index) {
    this.index = index;
  }

  // implementations for MemoryLocation

  @Override
  public  T extractValueOrDefault(
      JvmAbstractState abstractState, T defaultValue) {
    return (T) abstractState.peekOrDefault(index, defaultValue);
  }

  /** Returns the stack index from the top. */
  public int getIndex() {
    return index;
  }

  // implementations for Object

  @Override
  public boolean equals(Object obj) {
    if (!(obj instanceof JvmStackLocation)) {
      return false;
    }
    JvmStackLocation other = (JvmStackLocation) obj;
    return index == other.index;
  }

  @Override
  public int hashCode() {
    return Objects.hash(index);
  }

  @Override
  public String toString() {
    return "JvmStackLocation(" + index + ")";
  }
}