Merge pull request #5454 from danielguedesb/master

BAEL-2242
This commit is contained in:
José Carlos Valero Sánchez 2018-10-17 20:10:16 +01:00 committed by GitHub
commit a470906e66
No known key found for this signature in database
GPG Key ID: 4AEE18F83AFDEB23
5 changed files with 175 additions and 0 deletions

View File

@ -0,0 +1,19 @@
package com.baeldung.removal;
import java.util.ArrayList;
import java.util.Collection;
public class CollectionRemoveIf {
public static void main(String args[]) {
Collection<String> names = new ArrayList<>();
names.add("John");
names.add("Ana");
names.add("Mary");
names.add("Anthony");
names.add("Mark");
names.removeIf(e -> e.startsWith("A"));
System.out.println(String.join(",", names));
}
}

View File

@ -0,0 +1,28 @@
package com.baeldung.removal;
import java.util.ArrayList;
import java.util.Collection;
import java.util.Iterator;
public class Iterators {
public static void main(String args[]) {
Collection<String> names = new ArrayList<>();
names.add("John");
names.add("Ana");
names.add("Mary");
names.add("Anthony");
names.add("Mark");
Iterator<String> i = names.iterator();
while (i.hasNext()) {
String e = i.next();
if (e.startsWith("A")) {
i.remove();
}
}
System.out.println(String.join(",", names));
}
}

View File

@ -0,0 +1,23 @@
package com.baeldung.removal;
import java.util.ArrayList;
import java.util.Collection;
import java.util.stream.Collectors;
public class StreamFilterAndCollector {
public static void main(String args[]) {
Collection<String> names = new ArrayList<>();
names.add("John");
names.add("Ana");
names.add("Mary");
names.add("Anthony");
names.add("Mark");
Collection<String> filteredCollection = names
.stream()
.filter(e -> !e.startsWith("A"))
.collect(Collectors.toList());
System.out.println(String.join(",", filteredCollection));
}
}

View File

@ -0,0 +1,28 @@
package com.baeldung.removal;
import java.util.ArrayList;
import java.util.Collection;
import java.util.List;
import java.util.Map;
import java.util.stream.Collectors;
public class StreamPartitioningBy {
public static void main(String args[]) {
Collection<String> names = new ArrayList<>();
names.add("John");
names.add("Ana");
names.add("Mary");
names.add("Anthony");
names.add("Mark");
Map<Boolean, List<String>> classifiedElements = names
.stream()
.collect(Collectors.partitioningBy((String e) -> !e.startsWith("A")));
String matching = String.join(",", classifiedElements.get(Boolean.TRUE));
String nonMatching = String.join(",", classifiedElements.get(Boolean.FALSE));
System.out.println("Matching elements: " + matching);
System.out.println("Non matching elements: " + nonMatching);
}
}

View File

@ -0,0 +1,77 @@
package com.baeldung.removal;
import org.junit.Before;
import org.junit.Test;
import java.util.*;
import java.util.stream.Collectors;
import static org.hamcrest.Matchers.is;
import static org.junit.Assert.assertThat;
public class RemovalUnitTest {
Collection<String> names;
Collection<String> expected;
Collection<String> removed;
@Before
public void setupTestData() {
names = new ArrayList<>();
expected = new ArrayList<>();
removed = new ArrayList<>();
names.add("John");
names.add("Ana");
names.add("Mary");
names.add("Anthony");
names.add("Mark");
expected.add("John");
expected.add("Mary");
expected.add("Mark");
removed.add("Ana");
removed.add("Anthony");
}
@Test
public void givenCollectionOfNames_whenUsingIteratorToRemoveAllNamesStartingWithLetterA_finalListShouldContainNoNamesStartingWithLetterA() {
Iterator<String> i = names.iterator();
while (i.hasNext()) {
String e = i.next();
if (e.startsWith("A")) {
i.remove();
}
}
assertThat(names, is(expected));
}
@Test
public void givenCollectionOfNames_whenUsingRemoveIfToRemoveAllNamesStartingWithLetterA_finalListShouldContainNoNamesStartingWithLetterA() {
names.removeIf(e -> e.startsWith("A"));
assertThat(names, is(expected));
}
@Test
public void givenCollectionOfNames_whenUsingStreamToFilterAllNamesStartingWithLetterA_finalListShouldContainNoNamesStartingWithLetterA() {
Collection<String> filteredCollection = names
.stream()
.filter(e -> !e.startsWith("A"))
.collect(Collectors.toList());
assertThat(filteredCollection, is(expected));
}
@Test
public void givenCollectionOfNames_whenUsingStreamAndPartitioningByToFindNamesThatStartWithLetterA_shouldFind3MatchingAnd2NonMatching() {
Map<Boolean, List<String>> classifiedElements = names
.stream()
.collect(Collectors.partitioningBy((String e) -> !e.startsWith("A")));
assertThat(classifiedElements.get(Boolean.TRUE), is(expected));
assertThat(classifiedElements.get(Boolean.FALSE), is(removed));
}
}