package username.linear;

import java.io.PrintWriter;
import java.math.BigInteger;

/**
 * A generic assistant that helps test linear structures.
 * To use the tester, try something like the following
 *
 * <pre>
 * LinearTesterHelper assistant =
 *   new LinearTesterHelper(new LinearStructureOfYourChoice<String>());
 * assistant.runEmptyTest();
 * assistant.runPutTest();
 * assistant.runEmptyTest();
 * assistant.runGetTest();
 * assistant.runEmptyTest();
 * assistant.runSimpleTest();
 * assistant.runSimpleTest();
 * assistant.runClearTest();
 * assistant.runSimpleTest();
 * </pre>
 *
 * You can replicate that with
 *
 * <pre>
 * LinearTesterHelper assistant =
 *   new LinearTesterHelper(new LinearStructureOfYourChoice<String>());
 * assistant.runStandardTests();
 * </pre>
 *
 * @author Samuel A. Rebelsky
 * @version 1.1 of March 2006
 */
public class LinearTesterHelper
{
  // +--------+------------------------------------------------------------
  // | Fields |
  // +--------+

  /** The linear structure we're testing. */
  LinearStructure<String> victim;

  /** The PrintWriter used for output. */
  PrintWriter pen;


  // +-------------+-------------------------------------------------------
  // | Construtors |
  // +-------------+

  /**
   * Build a new tester for a particular linear structure.
   */
  public LinearTesterHelper(LinearStructure<String> _victim)
  {
    this.victim = _victim;
    this.pen = new PrintWriter(System.out, true);
  } // LinearTesterHelper(LinearStructure)


  // +---------+-----------------------------------------------------------
  // | Methods |
  // +---------+

  /**
   * Test the isEmpty method.
   */
  public void runEmptyTest()
  {
    this.pen.println("Testing isEmpty");
    if (this.victim.isEmpty()) {
      this.pen.println("  The structure is empty.");
    }
    else {
      this.pen.println("  The structure is not empty.");
    }
  } // runEmptyTest()

  /**
   * Test the put method.  The method should succeed.
   */
  public void runPutTest()
  {
    this.pen.println("Putting 'Alpha'");
    this.victim.put("Alpha");
    this.pen.println("  Done.");
  } // testPut()

  /**
   * Test the get method.  This method should succeed.
   */
  public void runGetTest()
  {
    this.pen.println("Getting a value");
    this.pen.println("  Got: " + this.victim.get());
  } // testGet()

  /**
   * Add a few values, remove fewer values.  It's helpful
   * to call this a few times to verify that we can continue
   * building upon the structure after removal.  It's also
   * helpful to call this after runClearTest to make sure that
   * that method works.
   */
  public void runSimpleTest()
  {
    this.pen.println("Adding five elements");
    for (int i = 0; i < 5; i++) {
      String istr = Integer.toString(i);
      this.pen.println("  Adding " + istr);
      this.victim.put(istr);
    } // for
    this.pen.println("Removing three elements");
    for (int i = 0; i < 3; i++) {
      this.pen.println("  Removing: " + this.victim.get());
    } // for
  } // runSimpleTest()

  /**
   * Remove all values from the linear structure.
   */
  public void runClearTest()
  {
    this.pen.println("Removing all elements.");
    while (!this.victim.isEmpty()) {
      this.pen.println("  Removing: " + this.victim.get());
    } // while
  } // runClearTest

  /**
   * The standard set of tests.
   */
  public void runStandardTests()
  {
    this.runEmptyTest();
    this.runPutTest();
    this.runEmptyTest();
    this.runGetTest();
    this.runEmptyTest();
    this.runSimpleTest();
    this.runSimpleTest();
    this.runClearTest();
    this.runSimpleTest();
  } // runStandardTests()
} // class LinearTesterHelper