MemoizedByte.java

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 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
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 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
 * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
 * version 2 for more details (a copy is included in the LICENSE file that
 * accompanied this code).
 *
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 * 2 along with this work; if not, write to the Free Software Foundation,
 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
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package sun.jvm.hotspot.utilities.memo;

/** A memoized byte. Override {@link #computeValue} in subclasses;
    call {@link #getValue} in using code. */

public abstract class MemoizedByte {
  private boolean computed;
  private byte value;

  /** Should compute the value of this memoized object. This will only
      be called once, upon the first call to {@link #getValue}. */
  protected abstract byte computeValue();

  /** Public accessor for the memoized value. */
  public byte getValue() {
    if (!computed) {
      value = computeValue();
      computed = true;
    }
    return value;
  }
}