java - 如何覆盖 Tapestry AlertManager

Question

我创建了扩展警报管理器:界面

public interface AlertManagerExt extends AlertManager {
    void successCode(String messageCode, Object... args);
    void infoCode(String messageCode, Object... args);
    void warnCode(String messageCode, Object... args);
    void errorCode(String messageCode, Object... args);
}

和实现

public class AlertManagerExtImpl extends AlertManagerImpl implements AlertManagerExt {

    private final Messages messages;

    public AlertManagerExtImpl(ApplicationStateManager asm, Request request, AjaxResponseRenderer ajaxResponseRenderer,
            PerthreadManager perThreadManager, Messages messages) {
        super(asm, request, ajaxResponseRenderer, perThreadManager);
        this.messages = messages;
    }

    @Override
    public void successCode(String messageCode, Object... args) {
        success(getMessage(messageCode, args));
    }

    @Override
    public void infoCode(String messageCode, Object... args) {
        info(getMessage(messageCode, args));
    }

    @Override
    public void warnCode(String messageCode, Object... args) {
        warn(getMessage(messageCode, args));
    }

    @Override
    public void errorCode(String messageCode, Object... args) {
        error(getMessage(messageCode, args));
    }

    protected String getMessage(String code, Object... args) {
        if (args.length > 0) {
            return messages.format(code, args);
        }
        return messages.get(code);
    }
}

当我尝试通过 Binder 绑定(bind)它时:

binder.bind(AlertManagerExt.class, AlertManagerExtImpl.class);

我遇到异常:

java.lang.RuntimeException: Service interface org.apache.tapestry5.alerts.AlertManager is matched by 2 services: AlertManager, AlertManagerExtImpl.  Automatic dependency resolution requires that exactly one service implement the interface.
at org.apache.tapestry5.ioc.internal.RegistryImpl.getServiceByTypeAlone(RegistryImpl.java:789)
at org.apache.tapestry5.ioc.internal.RegistryImpl.getServiceByTypeAndMarkers(RegistryImpl.java:797)
at org.apache.tapestry5.ioc.internal.RegistryImpl.getService(RegistryImpl.java:755)

我知道我可以复制并粘贴 AlertManager 中的所有方法并且不扩展它。但可能有更好的方法吗？

Answer 1

这是因为当您尝试仅按接口(interface)类型@Inject 时，Tapestry IoC 会尝试查找实现接口(interface)的所有服务。您的新 AlertManagerExt 也实现了 AlertManager 因此存在歧义。

这通常可以通过显式指定服务 ID 或标记注释来解决，但这不适用于您的情况，因为 Tapestry 的核心代码已经通过接口(interface) @Injecting AlertManager仅。