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    1   /*
    2    * $Id: Counter.java 471756 2006-11-06 15:01:43Z husted $
    3    *
    4    * Licensed to the Apache Software Foundation (ASF) under one
    5    * or more contributor license agreements.  See the NOTICE file
    6    * distributed with this work for additional information
    7    * regarding copyright ownership.  The ASF licenses this file
    8    * to you under the Apache License, Version 2.0 (the
    9    * "License"); you may not use this file except in compliance
    10   * with the License.  You may obtain a copy of the License at
    11   *
    12   *  http://www.apache.org/licenses/LICENSE-2.0
    13   *
    14   * Unless required by applicable law or agreed to in writing,
    15   * software distributed under the License is distributed on an
    16   * "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
    17   * KIND, either express or implied.  See the License for the
    18   * specific language governing permissions and limitations
    19   * under the License.
    20   */
    21  package org.apache.struts2.util;
    22
    23  import java.io.Serializable;
    24
    25
    26  /***
    27   * A bean that can be used to keep track of a counter.
    28   * <p/>
    29   * Since it is an Iterator it can be used by the iterator tag
    30   *
    31   */
    32  public class Counter implements java.util.Iterator, Serializable {
    33
    34      private static final long serialVersionUID = 2796965884308060179L;
    35
    36      boolean wrap = false;
    37
    38      // Attributes ----------------------------------------------------
    39      long first = 1;
    40      long current = first;
    41      long interval = 1;
    42      long last = -1;
    43
    44
    45      public void setAdd(long addition) {
    46          current += addition;
    47      }
    48
    49      public void setCurrent(long current) {
    50          this.current = current;
    51      }
    52
    53      public long getCurrent() {
    54          return current;
    55      }
    56
    57      public void setFirst(long first) {
    58          this.first = first;
    59          current = first;
    60      }
    61
    62      public long getFirst() {
    63          return first;
    64      }
    65
    66      public void setInterval(long interval) {
    67          this.interval = interval;
    68      }
    69
    70      public long getInterval() {
    71          return interval;
    72      }
    73
    74      public void setLast(long last) {
    75          this.last = last;
    76      }
    77
    78      public long getLast() {
    79          return last;
    80      }
    81
    82      // Public --------------------------------------------------------
    83      public long getNext() {
    84          long next = current;
    85          current += interval;
    86
    87          if (wrap && (current > last)) {
    88              current -= ((1 + last) - first);
    89          }
    90
    91          return next;
    92      }
    93
    94      public long getPrevious() {
    95          current -= interval;
    96
    97          if (wrap && (current < first)) {
    98              current += (last - first + 1);
    99          }
    100
    101         return current;
    102     }
    103
    104     public void setWrap(boolean wrap) {
    105         this.wrap = wrap;
    106     }
    107
    108     public boolean isWrap() {
    109         return wrap;
    110     }
    111
    112     public boolean hasNext() {
    113         return ((last == -1) || wrap) ? true : (current <= last);
    114     }
    115
    116     public Object next() {
    117         return new Long(getNext());
    118     }
    119
    120     public void remove() {
    121         // Do nothing
    122     }
    123 }