Assertion.java

/*
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*/

package jdsl.core.ref;



/** 
 * Helps to check invariant conditions in program and check
 * correctness of implementation.  Warning: not thread safe. Undefined
 * behavior if several threads fail on assertion checks
 * simultaneously.
 *
 * @author Benety Goh (bg@cs.brown.edu)
 * @version JDSL 2.1.1 
 * @deprecated Starting with Java 2 version 1.4 assertions are part of
 * the language, and thus this class is no longer necessary.
 */
public final class Assertion {

  /** 
   * private constructor so that we can't instantiate this class
   */
  private Assertion () {}

  /**
   * Never use this method to indicate bad user input; this method is
   * for asserting internal correctness of the implementation only.
   *
   * @param mustBeTrue expression that is assumed to be true
   * @exception AssertionException If mustBeTrue is false
   */
  public static void check (boolean mustBeTrue) throws AssertionException {
    if (!mustBeTrue)
      // use default assertion failure description
      throw new AssertionException();
  }

  /** 
   * Never use this method to indicate bad user input; this method is
   * for asserting internal correctness of the implementation only.
   *
   * @param mustBeTrue expression that is assumed to be true
   * @param message description of the problem
   * @exception AssertionException If mustBeTrue is false
   */
  public static void check (boolean mustBeTrue, String message)
    throws AssertionException {
    if (!mustBeTrue) 
      throw new AssertionException( message );
  }

}