discover_by_testing_fixed.java

public final class Configuration {
    private final String agent;
    private final String header;
    private final String version;

    public Configuration(final Storage storage) {
        this.agent = storage.get(KEY_AGENT);
        this.version = storage.get(KEY_VERSION);
        this.header = storage.get(KEY_HEADER);
    }

    public boolean isValid() {
        if (agent.length() == 0) return false;
        if (version.length() == 0) return false;
        return header.length() != 0;
    }

    public String getAgent() {
        return agent;
    }

    public String getHeader() {
        return header + "/" + VERSION_PREFIX + this.version;
    }

    public String getVersion() {
        return version;
    }
}