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BAEL-6838-index-of-set-element (#14747)

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Co-authored-by: Bhaskar <bhaskar.dastidar@freshworks.com>
This commit is contained in:
Bhaskar Ghosh Dastidar 2023-09-12 06:07:38 +05:30 committed by GitHub
parent 6978371d17
commit 42188fdc2d
4 changed files with 132 additions and 0 deletions
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6
core-java-modules/core-java-collections-set-2/pom.xml
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@ -20,6 +20,12 @@
<version>${junit-platform.version}</version> <version>${junit-platform.version}</version>
<scope>test</scope> <scope>test</scope>
</dependency> </dependency>
<dependency>
<groupId>org.apache.commons</groupId>
<artifactId>commons-collections4</artifactId>
<version>4.4</version>
</dependency>
<dependency> <dependency>
<groupId>org.testng</groupId> <groupId>org.testng</groupId>
<artifactId>testng</artifactId> <artifactId>testng</artifactId>

13
core-java-modules/core-java-collections-set-2/src/main/java/com/baeldung/indexawareset/IndexOfElementsInSet.java Normal file
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@ -0,0 +1,13 @@
package com.baeldung.indexawareset;
import java.util.ArrayList;
import java.util.List;
import java.util.Set;
public class IndexOfElementsInSet<E> {
public int getIndexOf(Set<E> set, E element) {
List<E> arrayList = new ArrayList<>();
arrayList.addAll(set);
return arrayList.indexOf(element);
}
}

20
core-java-modules/core-java-collections-set-2/src/main/java/com/baeldung/indexawareset/InsertionIndexAwareSet.java Normal file
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@ -0,0 +1,20 @@
package com.baeldung.indexawareset;
import java.util.LinkedHashSet;
public class InsertionIndexAwareSet<E> extends LinkedHashSet<E> {
public InsertionIndexAwareSet() {
super();
}
public int getIndexOf(E element) {
int index = 0;
for (E current : this) {
if (current.equals(element)) {
return index;
}
index++;
}
return -1;
}
}

93
core-java-modules/core-java-collections-set-2/src/test/java/com/baeldung/indexawareset/IndexOfSetElementsUsingListUnitTest.java Normal file
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@ -0,0 +1,93 @@
package com.baeldung.indexawareset;
import java.util.HashSet;
import java.util.LinkedHashSet;
import java.util.Set;
import java.util.TreeSet;
import org.apache.commons.collections4.set.ListOrderedSet;
import org.junit.Assert;
import org.junit.Test;
public class IndexOfSetElementsUsingListUnitTest {
@Test
public void givenHashSet_whenIndexOfElement_thenGivesIndex() {
Set<Integer> set = new HashSet<>();
set.add(100);
set.add(20);
set.add(300);
set.add(0);
set.add(-1);
set.add(300);
IndexOfElementsInSet<Integer> integerIndexOfElementsInSet = new IndexOfElementsInSet<>();
int index100 = integerIndexOfElementsInSet.getIndexOf(set, 100);
Assert.assertEquals(index100, integerIndexOfElementsInSet.getIndexOf(set, 100));
Assert.assertEquals(-1, integerIndexOfElementsInSet.getIndexOf(set, 12));
}
@Test
public void givenLinkedHashSet_whenIndexOfElement_thenGivesIndex() {
Set<Integer> set = new LinkedHashSet<>();
set.add(100);
set.add(20);
set.add(300);
set.add(0);
set.add(-1);
set.add(300);
IndexOfElementsInSet<Integer> integerIndexOfElementsInSet = new IndexOfElementsInSet<>();
Assert.assertEquals(0, integerIndexOfElementsInSet.getIndexOf(set, 100));
}
@Test
public void givenTreeSet_whenIndexOfElement_thenGivesIndex() {
Set<Integer> set = new TreeSet<>();
set.add(100);
set.add(20);
set.add(300);
set.add(0);
set.add(-1);
set.add(300);
IndexOfElementsInSet<Integer> integerIndexOfElementsInSet = new IndexOfElementsInSet<>();
Assert.assertEquals(0, integerIndexOfElementsInSet.getIndexOf(set, -1));
Assert.assertEquals(3, integerIndexOfElementsInSet.getIndexOf(set, 100));
}
@Test
public void givenIndexAwareSet_whenIndexOfElement_thenGivesIndex() {
InsertionIndexAwareSet<Integer> set = new InsertionIndexAwareSet<>();
set.add(100);
set.add(20);
set.add(300);
Assert.assertEquals(0, set.getIndexOf(100));
Assert.assertEquals(2, set.getIndexOf(300));
Assert.assertEquals(-1, set.getIndexOf(0));
}
@Test
public void givenIndexAwareSetWithStrings_whenIndexOfElement_thenGivesIndex() {
InsertionIndexAwareSet<String> set = new InsertionIndexAwareSet<>();
set.add("Go");
set.add("Java");
set.add("Scala");
set.add("Python");
Assert.assertEquals(0, set.getIndexOf("Go"));
Assert.assertEquals(2, set.getIndexOf("Scala"));
Assert.assertEquals(-1, set.getIndexOf("C++"));
}
@Test
public void givenListOrderedSet_whenIndexOfElement_thenGivesIndex() {
ListOrderedSet<Integer> set = new ListOrderedSet<>();
set.add(12);
set.add(0);
set.add(-1);
set.add(50);
Assert.assertEquals(0, set.indexOf(12));
Assert.assertEquals(2, set.indexOf(-1));
Assert.assertEquals(-1, set.indexOf(100));
}
}