Naming a method hashcode() or equal is either:

In both cases, the method should be renamed.

Noncompliant Code Example

public int hashcode() { /* ... */ }  // Noncompliant

public boolean equal(Object obj) { /* ... */ }  // Noncompliant

Compliant Solution

@Override
public int hashCode() { /* ... */ }

public boolean equals(Object obj) { /* ... */ }