src/main/java/org/fest/assertions/internal/Objects.java
public void assertNotSame(Description description, Object actual, Object other) {
    if (actual == other) {
      String format = "expected not same:<%s>";
      throw failures.failure(description, new BasicErrorMessageFactory(format, actual));
    }
  }
public void assertNotSame(Description description, Object actual, Object other) {
    if (actual == other) {
      String format = "expected not same:<%s>";
      throw failures.failure(description, new BasicErrorMessageFactory(format, actual));
    }
  }
Asserts that two objects do not refer to the same instance.

@param description the description of the <em>actual</em> object.
@param actual the <em>actual</em> object.
@param other the object to compare {@code actual} to.
@throws AssertionError if the given objects refer to the same instance.