public long maxConnectionAgeMillis() {
        return get(MAX_CONNECTION_AGE_MILLIS);
    }
Returns the client-side max age of a connection for keep-alive in milliseconds.
If the value is greater than {@code 0}, a connection is disconnected after the specified
amount of the time since the connection was established.
core/src/main/java/com/linecorp/armeria/client/ClientFactoryOptions.java