### Question:
BitcoinSerializer extends MessageSerializer { @Override public boolean equals(Object o) { if (this == o) return true; if (o == null || !(o instanceof BitcoinSerializer)) return false; BitcoinSerializer other = (BitcoinSerializer) o; return Objects.equals(params, other.params) && protocolVersion == other.protocolVersion && parseRetain == other.parseRetain; } BitcoinSerializer(NetworkParameters params, boolean parseRetain);  BitcoinSerializer(NetworkParameters params, int protocolVersion, boolean parseRetain); @Override BitcoinSerializer withProtocolVersion(int protocolVersion); @Override int getProtocolVersion(); @Override void serialize(String name, byte[] message, OutputStream out); @Override void serialize(Message message, OutputStream out); @Override Message deserialize(ByteBuffer in); @Override BitcoinPacketHeader deserializeHeader(ByteBuffer in); @Override Message deserializePayload(BitcoinPacketHeader header, ByteBuffer in); NetworkParameters getParameters(); @Override AddressMessage makeAddressMessage(byte[] payloadBytes, int length); @Override Message makeAlertMessage(byte[] payloadBytes); @Override Block makeBlock(final byte[] payloadBytes, final int offset, final int length); @Override Message makeBloomFilter(byte[] payloadBytes); @Override FilteredBlock makeFilteredBlock(byte[] payloadBytes); @Override InventoryMessage makeInventoryMessage(byte[] payloadBytes, int length); @Override Transaction makeTransaction(byte[] payloadBytes, int offset, int length, byte[] hashFromHeader); @Override void seekPastMagicBytes(ByteBuffer in); @Override boolean isParseRetainMode(); @Override boolean equals(Object o); @Override int hashCode();  }### Answer:
@Test public void testEquals() { assertTrue(MAINNET.getDefaultSerializer().equals(MAINNET.getDefaultSerializer())); assertFalse(MAINNET.getDefaultSerializer().equals(TestNet3Params.get().getDefaultSerializer())); assertFalse(MAINNET.getDefaultSerializer().equals(MAINNET.getDefaultSerializer().withProtocolVersion(0))); }