code: /*
   * Copyright (c) 2017-2018 The Regents of the University of California
   *
   * All rights reserved.
   *
   * Redistribution and use in source and binary forms, with or without
   * modification, are permitted provided that the following conditions are
   * met:
   *
   * 1. Redistributions of source code must retain the above copyright
   * notice, this list of conditions and the following disclaimer.
   *
   * 2. Redistributions in binary form must reproduce the above copyright
   * notice, this list of conditions and the following disclaimer in the
   * documentation and/or other materials provided with the distribution.
   *
   * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
   * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
   * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
   * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
   * HOLDER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
   * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
   * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
   * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
   * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
   * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
   * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
   */
  package edu.berkeley.cs.jqf.fuzz.ei;
  
  import java.util.Arrays;
  
  /**
   * A representation of an execution index sans the counts, equivalent to
   * a call stack.
   *
   * @author Rohan Padhye
   */
  public class ExecutionContext {
  
      private final int[] ec;
  
      /**
       * Create an execution context by extracting the call stack
       * from an execution index.
       *
       * @param executionIndex the execution index to copy call sites from
       */
      public ExecutionContext(ExecutionIndex executionIndex) {
          int[] ei = executionIndex.ei;
  
          // Take every even element from the execution index
          ec = new int[ei.length / 2];
          for (int i = 0; i < ec.length; i++) {
              ec[i] = ei[2*i];
          }
      }
  
      @Override
      public int hashCode() {
          return Arrays.hashCode(ec);
      }
  
      @Override
      public boolean equals(Object other) {
          if (other != null && other instanceof ExecutionContext) {
              return Arrays.equals(ec, ((ExecutionContext) other).ec);
          } else {
              return false;
          }
      }
  
      @Override
      public String toString() {
          return Arrays.toString(ec);
      }
  }
  