closurecomparatortest.groovy

来自「Groovy动态语言 运行在JVM中的动态语言 可以方便的处理业务逻辑变化大的业」· GROOVY 代码 · 共 96 行

/*
 $Id: ClosureComparatorTest.groovy 3827 2006-06-09 13:50:11Z tug $

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 */

/**
 * Tests for ClosureComparator
 *
 * @author Alexey Verkhovsky
 * @version $Revision: 3827 $
 */
 class ClosureComparatorTest extends GroovyTestCase {


  public void testClosureComparatorForGroovyObjects() {

    def comparator = new ClosureComparator() { one, another ->
      one.greaterThan(another)
    }

    def one = new ComparableFoo(5)
    def another = new ComparableFoo(-5)

    assertEquals(10, comparator.compare(one, another))
    assertEquals(0, comparator.compare(one, one))
    assertEquals(-10, comparator.compare(another, one))

  }

  public void testClosureComparatorForNumericTypes() {

    def comparator = new ClosureComparator() { one, another ->
      one - another
    }

    assertEquals(1, comparator.compare(Integer.MAX_VALUE, Integer.MAX_VALUE-1))
    assertEquals(0, comparator.compare(Double.MIN_VALUE, Double.MIN_VALUE))
    assertEquals(-1, comparator.compare(Long.MIN_VALUE, Long.MIN_VALUE+1))
  }

}

class ComparableFoo {
  long value

  public ComparableFoo(long theValue) {
    this.value = theValue
  }

  def greaterThan(anotherFoo) {
    return (this.value - anotherFoo.value)
  }
}