private JsonRpcMethod ethGetBlockNumber() {
    final JsonRpcMethod method = methods.get(ETH_METHOD);
    assertThat(method).isNotNull();
    return method;
  }
The Boolean type second parameter, denotes whether to retrieve the complete transaction or just
the transaction hash.
ethereum/api/src/integration-test/java/org/hyperledger/besu/ethereum/api/jsonrpc/methods/fork/frontier/EthGetBlockByNumberIntegrationTest.java