类 ListTool

java.lang.Object
org.apache.velocity.tools.generic.ListTool

@Deprecated @DefaultKey("lists") public class ListTool extends Object
已过时。
Tool for working with Lists and arrays in Velocity templates.

With the release of Velocity 1.6, this class is largely obsolete since Velocity 1.6 now allows all List methods to be called on arrays within templates.

It provides a method to get and set specified elements. Also provides methods to perform the following actions to Lists and arrays:

  • Check if it is empty.
  • Check if it contains a certain element.

 Example uses:
  $primes                    -> new int[] {2, 3, 5, 7}
  $lists.size($primes)        -> 4
  $lists.get($primes, 2)      -> 5
  $lists.set($primes, 2, 1)   -> (primes[2] becomes 1)
  $lists.get($primes, 2)      -> 1
  $lists.isEmpty($primes)     -> false
  $lists.contains($primes, 7) -> true

 Example tools.xml config (if you want to use this with VelocityView):
 <tools>
   <toolbox scope="application">
     <tool class="org.apache.velocity.tools.generic.ListTool"/>
   </toolbox>
 </tools>
 

This tool is entirely threadsafe, and has no instance members. It may be used in any scope (request, session, or application).

从以下版本开始:
VelocityTools 1.2
版本:
$Id: $
作者:
Shinobu Kawai
  • 构造器详细资料

    • ListTool

      public ListTool()
      已过时。
  • 方法详细资料

    • get

      public Object get(Object list, int index)
      已过时。
      Gets the specified element of a List/array. It will return null under the following conditions:
      • list is null.
      • list is not a List/array.
      • list doesn't have an indexth value.
      参数:
      list - the List/array object.
      index - the index of the List/array to get.
      返回:
      the specified element of the List/array.
    • getFromArray

      private Object getFromArray(Object array, int index)
      已过时。
      Gets the specified element of an array.
      参数:
      array - the array object.
      index - the index of the array to get.
      返回:
      the specified element of the array.
    • set

      public Object set(Object list, int index, Object value)
      已过时。
      Sets the specified element of a List/array. It will return null under the following conditions:
      • list is null.
      • list is not a List/array.
      • list doesn't have an indexth value.
      参数:
      list - the List/array object.
      index - the index of the List/array to set.
      value - the element to set.
      返回:
      blank if set, null if not set.
    • setToArray

      private Object setToArray(Object array, int index, Object value)
      已过时。
      Sets the specified element of an array.
      参数:
      array - the array object.
      index - the index of the array to set.
      value - the element to set.
      返回:
      blank if set, null if not set.
    • size

      public Integer size(Object list)
      已过时。
      Gets the size of a List/array. It will return null under the following conditions:
      • list is null.
      • list is not a List/array.
      参数:
      list - the List object.
      返回:
      the size of the List.
    • isArray

      public boolean isArray(Object object)
      已过时。
      Checks if an object is an array.
      参数:
      object - the object to check.
      返回:
      true if the object is an array.
    • isList

      public boolean isList(Object object)
      已过时。
      Checks if an object is a List.
      参数:
      object - the object to check.
      返回:
      true if the object is a List.
    • isEmpty

      public Boolean isEmpty(Object list)
      已过时。
      Checks if a List/array is empty.
      参数:
      list - the List/array to check.
      返回:
      true if the List/array is empty.
    • contains

      public Boolean contains(Object list, Object element)
      已过时。
      Checks if a List/array contains a certain element.
      参数:
      list - the List/array to check.
      element - the element to check.
      返回:
      true if the List/array contains the element.
    • arrayContains

      private Boolean arrayContains(Object array, Object element)
      已过时。
      Checks if an array contains a certain element.
      参数:
      array - the array to check.
      element - the element to check.
      返回:
      true if the array contains the element.
    • equals

      private boolean equals(Object what, Object with)
      已过时。
      Check if two objects are equal.
      参数:
      what - an object
      with - another object.
      返回:
      true if the two objects are equal.