### Question:
ChatMessage { public boolean equalContent(ChatMessage o) { if (groupId != o.groupId) return false; if (userId != o.userId) return false; if (content != null ? !content.equals(o.content) : o.content != null) { return false; } return timeSent != null ? timeSent.equals(o.timeSent) : o.timeSent == null; } ChatMessage(int groupId,
                       String content,
                       int userId,
                       String username,
                       Date timeSent); int getMessageId(); void setMessageId(int messageId); int getGroupId(); void setGroupId(int groupId); String getContent(); void setContent(String content); int getUserId(); void setUserId(int userId); String getUsername(); void setUsername(String username); Date getTimeSent(); void setTimeSent(Date timeSent); boolean equalContent(ChatMessage o); @Override boolean equals(Object o); @Override int hashCode();  }### Answer:
@Test public void equalContent() throws Exception { assertTrue("same message", message1.equalContent(message1)); assertTrue("different messages", message1.equalContent(message3)); }