Merge remote-tracking branch 'origin/main'

mihxil-math/src/main/java/org/meeuw/math/CollectionUtils.java

@@ -18,6 +18,8 @@
 import java.util.*;
 import java.util.function.Supplier;
 
+import org.checkerframework.checker.nullness.qual.NonNull;
+import org.checkerframework.checker.nullness.qual.Nullable;
 import org.meeuw.math.operators.OperatorInterface;
 
 import static java.util.Collections.unmodifiableNavigableSet;
@@ -82,4 +84,36 @@ public V get() {
             }
         };
     }
+
+
+    /**
+     * Wraps the given set in a new set, with the same elements.
+     * <p>
+     * The only difference will be that its {@link Set#contains(Object)} will simply return {@code false} if the argument is {@code null}.
+     * @since 0.12
+     */
+    public static <P> Set<@NonNull P> nullSafeSet(@NonNull final Set<@NonNull P> set) {
+        return new AbstractSet<P>() {
+            @Override
+            public @NonNull Iterator<P> iterator() {
+                return set.iterator();
+            }
+
+            @Override
+            public int size() {
+                return set.size();
+            }
+
+            @Override
+            public boolean add(@NonNull P o) {
+                return set.add(o);
+            }
+
+            @Override
+            public boolean contains(@Nullable Object o) {
+                return o != null && set.contains(o);
+            }
+        };
+    }
+
 }

mihxil-math/src/test/java/org/meeuw/test/math/CollectionUtilsTest.java

@@ -15,16 +15,20 @@
  */
 package org.meeuw.test.math;
 
-import java.util.ArrayList;
-import java.util.List;
+import lombok.SneakyThrows;
+
+import java.util.*;
 import java.util.concurrent.*;
 import java.util.concurrent.atomic.AtomicInteger;
 import java.util.function.Supplier;
-import lombok.SneakyThrows;
-import static org.assertj.core.api.Assertions.assertThat;
+
 import org.junit.jupiter.api.Test;
+
 import org.meeuw.math.CollectionUtils;
 
+import static org.assertj.core.api.Assertions.assertThat;
+import static org.assertj.core.api.Assertions.assertThatThrownBy;
+
 public class CollectionUtilsTest {
 
     @Test
@@ -42,6 +46,7 @@ public Integer get() {
         Supplier<Integer> memoize = CollectionUtils.memoize(sup);
         ExecutorService executor = Executors.newFixedThreadPool(10);
 
+
         List<Future<Integer>> f = new ArrayList<>();
         for (int i = 0; i < 5; i++) {
             f.add(executor.submit(new Callable<Integer>() {
@@ -56,4 +61,24 @@ public Integer call() {
         }
         executor.shutdown();
     }
+
+
+    @Test
+    void nullSafeSet() {
+        Set<String> set = Set.of("a", "b");
+
+        assertThatThrownBy(() -> set.contains(null)).isInstanceOf(NullPointerException.class);
+
+        Set<String> nullSafeSet = CollectionUtils.nullSafeSet(set);
+
+        assertThat(nullSafeSet.contains(null)).isFalse();
+        assertThat(nullSafeSet.contains("a")).isTrue();
+
+        assertThat(nullSafeSet.size()).isEqualTo(2);
+
+        assertThatThrownBy(() -> nullSafeSet.add(null)).isInstanceOf(UnsupportedOperationException.class);
+
+        assertThat(nullSafeSet.iterator()).asList().containsExactly("a", "b");
+    }
+
 }

pom.xml

@@ -38,11 +38,11 @@
     <!-- test dependencies -->
     <junit.version>5.10.1</junit.version>
     <jacoco.version>0.8.11</jacoco.version>
-    <assertj.version>3.24.2</assertj.version>
+    <assertj.version>3.25.2</assertj.version>
     <jqwik.version>1.7.4</jqwik.version> <!-- 1.8 is out, but fails a lot of things related to generics? -->
     <reflections.version>0.10.2</reflections.version>
-    <hibernate-validator.version>7.0.5.Final</hibernate-validator.version>
-    <log4j.version>2.21.1</log4j.version>
+    <hibernate-validator.version>8.0.1.Final</hibernate-validator.version>
+    <log4j.version>2.22.1</log4j.version>
 
   </properties>