Class ComparatorHelper

java.lang.Object
com.tangosol.coherence.rest.util.ComparatorHelper

public class ComparatorHelper extends Object
ComparatorHelper is a utility class that provides a factory method used to create a java.util.Comparator instance from a string expression.

The string expression should be in the form of comma-separated values, where each value represents the name of property whose value is used as input to the Comparator#compare(Object, Object) method and an optional order string ("asc" or "desc"). If not specified, ascending order will be assumed.

For example, the string name:asc,dateOfBirth:desc will create the following comparator chain:

new ChainedComparator(new Comparator[]
    {
    new ExtractorComparator(new ReflectionExtractor("getName")),
    new InverseComparator(new ExtractorComparator(new ReflectionExtractor("getDateOfBirth")))
    });

Author:
ic 2011.06.30
  • Constructor Details

    • ComparatorHelper

      public ComparatorHelper()
  • Method Details

    • createComparator

      public static Comparator createComparator(String sExpr)
      Create a new Comparator from the specified string.
      Parameters:
      sExpr - a string expression representing a Comparator. Contains a list of property name/ordering pairs, separated by a colon. For example:
      • name:asc,dateOfBirth:desc
      • address.state,address.zip:desc
      Returns:
      Comparator representing specified string expression