Package org.apache.velocity.tools.generic

Class AlternatorTool

  • @DefaultKey("alternator")
public class AlternatorTool
extends SafeConfig
    Simple tool to provide easy in-template instantiation of Alternators from varying "list" types or individual arguments.

    Example Use: 

     tools.xml...
 <tools>
   <toolbox scope="application">
     <tool class="org.apache.velocity.tools.generic.AlternatorTool"/>
   </toolbox>
 </tools>

 template...
 #set( $color = $alternator.auto('red', 'blue') )
 ## use manual alternation for this one
 #set( $style = $alternator.manual('hip','fly','groovy') )
 #foreach( $i in [1..5] )
   Number $i is $color and $style. I dig $style.next numbers.
 #end *

 output...
   Number 1 is red and hip. I dig hip numbers.
   Number 2 is blue and fly. I dig fly numbers.
   Number 3 is red and groovy. I dig groovy numbers.
   Number 4 is blue and hip. I dig hip numbers.
   Number 5 is red and fly. I dig fly numbers.

    Since:
    Velocity Tools 1.2
    Version:
    $Revision$ $Date$

    • Constructor Detail

      • AlternatorTool

        public AlternatorTool()

    • Method Detail

      • configure

        protected void configure​(ValueParser parser)
        Looks for a default auto-alternate value in the given params, if not, set the default to true.
        Overrides:
        configure in class SafeConfig

      • getAutoAlternateDefault

        public boolean getAutoAlternateDefault()
        Returns true if the default for auto-alternating is true.
        Since:
        VelocityTools 1.3

      • setAutoAlternateDefault

        protected void setAutoAlternateDefault​(boolean bool)
        Sets the default for auto-alternating.
        Since:
        VelocityTools 1.3

      • make

        public Alternator make​(boolean auto,
                       Object... list)
        Returns a new Alternator for the specified list with the specified automatic shifting preference.
        Parameters:
        auto - See Alternator.setAuto(boolean auto).
        list - The list of elements to alternate.

      • auto

        public Alternator auto​(Object... list)
        Make an automatic Alternator from the specified objects.
        Returns:
        a new, automatic Alternator with the specified values or null if there are none specified.
        Since:
        VelocityTools 1.3

      • manual

        public Alternator manual​(Object... list)
        Make a manual Alternator from the specified objects.
        Returns:
        a new, manual Alternator with the values in the array or null if the array is null.
        Since:
        VelocityTools 1.3