Groovy example source code file (ClosureComparatorTest.groovy)

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Java - Groovy tags/keywords

closurecomparator, closurecomparator, closurecomparatortest, closurecomparatortest, comparablefoo, comparablefoo, groovytestcase, groovytestcase

The Groovy ClosureComparatorTest.groovy source code

/*
 * Copyright 2003-2011 the original author or authors.
 *
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 *     http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */
package groovy

/**
 * Tests for ClosureComparator
 *
 * @author Alexey Verkhovsky
 * @version $Revision: 21515 $
 */
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)
    }
}