Code examples for the articl on Apache bags (#2671)
This commit is contained in:
adamd1985
Grzegorz Piwowarek
parent
2beb5f012c
commit
8bf825d046
|
|
@ -1,85 +1,111 @@
|
|||
package com.baeldung.commons.collections4;
|
||||
|
||||
import java.util.ArrayList;
|
||||
import java.util.List;
|
||||
|
||||
import org.apache.commons.collections4.Bag;
|
||||
import org.apache.commons.collections4.bag.CollectionBag;
|
||||
import org.apache.commons.collections4.bag.HashBag;
|
||||
import org.apache.commons.collections4.bag.TreeBag;
|
||||
import org.junit.Assert;
|
||||
import org.junit.Before;
|
||||
import org.apache.commons.collections4.SortedBag;
|
||||
import org.apache.commons.collections4.bag.*;
|
||||
import org.junit.Test;
|
||||
|
||||
import java.util.ArrayList;
|
||||
import java.util.Arrays;
|
||||
import java.util.Collection;
|
||||
|
||||
import static org.hamcrest.MatcherAssert.assertThat;
|
||||
import static org.hamcrest.Matchers.not;
|
||||
import static org.hamcrest.core.Is.is;
|
||||
import static org.hamcrest.core.IsEqual.equalTo;
|
||||
|
||||
public class BagTests {
|
||||
|
||||
Bag<String> baseBag;
|
||||
TreeBag<String> treeBag;
|
||||
|
||||
@Before
|
||||
public void before() {
|
||||
baseBag = new HashBag<String>();
|
||||
treeBag = new TreeBag<String>();
|
||||
treeBag = new TreeBag<String>();
|
||||
}
|
||||
|
||||
@Test
|
||||
public void whenAdd_thenRemoveFromBaseBag_thenContainsCorrect() {
|
||||
baseBag.add("apple", 2);
|
||||
baseBag.add("lemon", 6);
|
||||
baseBag.add("lime");
|
||||
|
||||
baseBag.remove("lemon");
|
||||
Assert.assertEquals(3, baseBag.size());
|
||||
Assert.assertFalse(baseBag.contains("lemon"));
|
||||
|
||||
Assert.assertTrue(baseBag.uniqueSet().contains("apple"));
|
||||
|
||||
List<String> containList = new ArrayList<String>();
|
||||
containList.add("apple");
|
||||
containList.add("lemon");
|
||||
containList.add("lime");
|
||||
Assert.assertFalse(baseBag.containsAll(containList));
|
||||
}
|
||||
|
||||
@Test
|
||||
public void whenAdd_thenRemoveFromBaseCollectionBag_thenContainsCorrect() {
|
||||
baseBag.add("apple", 2);
|
||||
baseBag.add("lemon", 6);
|
||||
baseBag.add("lime");
|
||||
|
||||
CollectionBag<String> baseCollectionBag = new CollectionBag<String>(
|
||||
baseBag);
|
||||
|
||||
baseCollectionBag.remove("lemon");
|
||||
Assert.assertEquals(8, baseCollectionBag.size());
|
||||
Assert.assertTrue(baseCollectionBag.contains("lemon"));
|
||||
|
||||
baseCollectionBag.remove("lemon",1);
|
||||
Assert.assertEquals(7, baseCollectionBag.size());
|
||||
|
||||
Assert.assertTrue(baseBag.uniqueSet().contains("apple"));
|
||||
|
||||
List<String> containList = new ArrayList<String>();
|
||||
containList.add("apple");
|
||||
containList.add("lemon");
|
||||
containList.add("lime");
|
||||
Assert.assertTrue(baseBag.containsAll(containList));
|
||||
}
|
||||
|
||||
@Test
|
||||
public void whenAddtoTreeBag_thenRemove_thenContainsCorrect() {
|
||||
treeBag.add("banana", 8);
|
||||
treeBag.add("apple", 2);
|
||||
treeBag.add("lime");
|
||||
|
||||
Assert.assertEquals(11, treeBag.size());
|
||||
Assert.assertEquals("apple", treeBag.first());
|
||||
Assert.assertEquals("lime", treeBag.last());
|
||||
|
||||
treeBag.remove("apple");
|
||||
Assert.assertEquals(9, treeBag.size());
|
||||
Assert.assertEquals("banana", treeBag.first());
|
||||
|
||||
}
|
||||
|
||||
@Test
|
||||
public void givenMultipleCopies_whenAdded_theCountIsKept() {
|
||||
Bag<Integer> bag = new HashBag<>(
|
||||
Arrays.asList(new Integer[] { 1, 2, 3, 3, 3, 1, 4 }));
|
||||
|
||||
assertThat(bag.getCount(1), equalTo(2));
|
||||
}
|
||||
|
||||
@Test
|
||||
public void givenBag_whenBagAddAPILikeCollectionAPI_thenFalse() {
|
||||
Collection<Integer> collection = new ArrayList<>();
|
||||
|
||||
// Collection contract defines that add() should return true
|
||||
assertThat(collection.add(9), is(true));
|
||||
|
||||
// Even when element is already in the collection
|
||||
collection.add(1);
|
||||
assertThat(collection.add(1), is(true));
|
||||
|
||||
Bag<Integer> bag = new HashBag<>();
|
||||
|
||||
// Bag returns true on adding a new element
|
||||
assertThat(bag.add(9), is(true));
|
||||
|
||||
bag.add(1);
|
||||
// But breaks the contract with false when it has to increment the count
|
||||
assertThat(bag.add(1), is(not(true)));
|
||||
}
|
||||
|
||||
@Test
|
||||
public void givenDecoratedBag_whenBagAddAPILikeCollectionAPI_thenTrue() {
|
||||
Bag<Integer> bag = CollectionBag.collectionBag(new HashBag<>());
|
||||
|
||||
bag.add(1);
|
||||
// This time the behavior is compliant to the Java Collection
|
||||
assertThat(bag.add(1), is((true)));
|
||||
}
|
||||
|
||||
@Test
|
||||
public void givenAdd_whenCountOfElementsDefined_thenCountAreAdded() {
|
||||
Bag<Integer> bag = new HashBag<>();
|
||||
|
||||
// Adding 1 for 5 times
|
||||
bag.add(1, 5);
|
||||
assertThat(bag.getCount(1), equalTo(5));
|
||||
}
|
||||
|
||||
@Test
|
||||
public void givenMultipleCopies_whenRemove_allAreRemoved() {
|
||||
Bag<Integer> bag = new HashBag<>(
|
||||
Arrays.asList(new Integer[] { 1, 2, 3, 3, 3, 1, 4 }));
|
||||
|
||||
// From 3 we delete 1, 2 remain
|
||||
bag.remove(3, 1);
|
||||
assertThat(bag.getCount(3), equalTo(2));
|
||||
|
||||
// From 2 we delete all
|
||||
bag.remove(1);
|
||||
assertThat(bag.getCount(1), equalTo(0));
|
||||
}
|
||||
|
||||
@Test
|
||||
public void givenTree_whenDuplicateElementsAdded_thenSort() {
|
||||
TreeBag<Integer> bag = new TreeBag<>(
|
||||
Arrays.asList(new Integer[] { 7, 5, 1, 7, 2, 3, 3, 3, 1, 4, 7 }));
|
||||
|
||||
assertThat(bag.first(), equalTo(1));
|
||||
assertThat(bag.getCount(bag.first()), equalTo(2));
|
||||
assertThat(bag.last(), equalTo(7));
|
||||
assertThat(bag.getCount(bag.last()), equalTo(3));
|
||||
}
|
||||
|
||||
@Test
|
||||
public void givenDecoratedTree_whenTreeAddAPILikeCollectionAPI_thenTrue() {
|
||||
SortedBag<Integer> bag = CollectionSortedBag
|
||||
.collectionSortedBag(new TreeBag<>());
|
||||
|
||||
bag.add(1);
|
||||
assertThat(bag.add(1), is((true)));
|
||||
}
|
||||
|
||||
@Test
|
||||
public void givenSortedBag_whenDuplicateElementsAdded_thenSort() {
|
||||
SynchronizedSortedBag<Integer> bag = SynchronizedSortedBag
|
||||
.synchronizedSortedBag(new TreeBag<>(
|
||||
Arrays.asList(new Integer[] { 7, 5, 1, 7, 2, 3, 3, 3, 1, 4, 7 })));
|
||||
|
||||
assertThat(bag.first(), equalTo(1));
|
||||
assertThat(bag.getCount(bag.first()), equalTo(2));
|
||||
assertThat(bag.last(), equalTo(7));
|
||||
assertThat(bag.getCount(bag.last()), equalTo(3));
|
||||
}
|
||||
}
|
||||
|
|
|
|||
Loading…
Reference in New Issue