Java代碼
  1. <s:bean?name= "org.apache.struts2.util.Counter" ?id= "counter" >????
  2. ??<s:param?name="first"?value="1"?/>????
  3. ??<s:param?name="last"?value="10"?/>????
  4. ??<s:iterator>????
  5. ????counter:<s:property?value="current-1"/>????
  6. ??</s:iterator>????
  7. </s:bean>????

其中first屬性指定循環起始值，last指定循環終止值，其它相關屬性可以查看org.apache.struts2.util.Counter類源碼。在下面迭代器中輸入循環的當前值，即：current-1

Counter類源碼
  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. }?