finishing the guava ordering examples

This commit is contained in:
Eugen Paraschiv 2013-10-25 13:33:16 +03:00
parent 2a5442477d
commit 31de9bbf62
1 changed files with 52 additions and 0 deletions

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@ -1,5 +1,6 @@
package org.baeldung.guava.collections;
import static org.hamcrest.Matchers.equalTo;
import static org.hamcrest.Matchers.nullValue;
import static org.junit.Assert.assertFalse;
import static org.junit.Assert.assertThat;
@ -11,6 +12,7 @@ import java.util.List;
import org.junit.Test;
import com.google.common.base.Functions;
import com.google.common.collect.Lists;
import com.google.common.collect.Ordering;
import com.google.common.primitives.Ints;
@ -59,6 +61,16 @@ public class GuavaOrderingExamplesTest {
assertTrue(Ordering.natural().isOrdered(toSort));
}
// checking string ordering
@Test
public final void givenCollectionContainsDuplicates_whenCheckingStringOrdering_thenNo() {
final List<Integer> toSort = Arrays.asList(3, 5, 4, 2, 1, 2);
Collections.sort(toSort, Ordering.natural());
assertFalse(Ordering.natural().isStrictlyOrdered(toSort));
}
// custom - by length
@Test
@ -124,4 +136,44 @@ public class GuavaOrderingExamplesTest {
assertTrue(expectedOrder.isOrdered(toSort));
}
// binary search
@Test
public final void whenPerformingBinarySearch_thenFound() {
final List<Integer> toSort = Arrays.asList(1, 2, 11);
Collections.sort(toSort, Ordering.usingToString());
final int found = Ordering.usingToString().binarySearch(toSort, 2);
System.out.println(found);
}
// min/max without actually sorting
@Test
public final void whenFindingTheMinimalElementWithoutSorting_thenFound() {
final List<Integer> toSort = Arrays.asList(2, 1, 11, 100, 8, 14);
final int found = Ordering.natural().min(toSort);
assertThat(found, equalTo(1));
}
@Test
public final void whenFindingTheFirstFewElements_thenCorrect() {
final List<Integer> toSort = Arrays.asList(2, 1, 11, 100, 8, 14);
final List<Integer> leastOf = Ordering.natural().leastOf(toSort, 3);
final List<Integer> expected = Lists.newArrayList(1, 2, 8);
assertThat(expected, equalTo(leastOf));
}
// order the results of a Function
@Test
public final void givenListOfNumbers_whenRunningAToStringFunctionThenSorting_thenCorrect() {
final List<Integer> toSort = Arrays.asList(2, 1, 11, 100, 8, 14);
final Ordering<Object> ordering = Ordering.natural().onResultOf(Functions.toStringFunction());
final List<Integer> sortedCopy = ordering.sortedCopy(toSort);
final List<Integer> expected = Lists.newArrayList(1, 100, 11, 14, 2, 8);
assertThat(expected, equalTo(sortedCopy));
}
}