ClassWithoutHashCodeInHashStructureCheck.java

import java.util.HashMap;
import java.util.HashSet;
import java.util.Hashtable;
import java.util.LinkedHashMap;
import java.util.Map;
import java.util.Set;
import java.util.TreeMap;
import java.util.TreeSet;

class Test<K> {
  Map<A, Object> m1 = new HashMap<>(); // Compliant
  Map<B, Object> m2 = new Hashtable<>(); // Noncompliant {{Add a "hashCode()" method to "B" or remove it from this hash.}}
  Map<C, Object> m3 = new LinkedHashMap<>(); // Compliant
  Map<D, Object> m4 = new LinkedHashMap<>(); // Compliant

  Set<A> s1 = new HashSet<>(); // Compliant
  Set<B> s2 = new TreeSet<>(); // Compliant
  Set<B> s3 = new HashSet<>(); // Noncompliant {{Add a "hashCode()" method to "B" or remove it from this hash.}}
  Set<C> s4 = new HashSet<>(); // Compliant
  Set<K> s5 = new HashSet<K>(); // Compliant
  Set s6 = new HashSet(); // Compliant
}

class A {
  boolean equals = false;
  boolean equals(Object o1, object o2) { return false; }
  boolean equals(A a) { return false; }
}

class B {
  @Override
  public boolean equals(Object obj) { return false; }

  int hashCode = 1;
  int hashCode(int i) { return 0; }
}

class C {
  @Override
  public int hashCode() { return 0; }
}

class D {
  @Override
  public boolean equals(Object obj) { return false; }

  @Override
  public int hashCode() { return 0; }
}