前面學了rpc的filter,那麼這模塊就簡單了
dubbo-filter-cache和dubbo-filter-validation
dubbo-filter-cache
通過判斷是否命中緩存,來決定是否都cache
public Result invoke(Invoker<?> invoker, Invocation invocation) throws RpcException {
if (cacheFactory != null && ConfigUtils.isNotEmpty(invoker.getUrl().getMethodParameter(invocation.getMethodName(), Constants.CACHE_KEY))) {
Cache cache = cacheFactory.getCache(invoker.getUrl().addParameter(Constants.METHOD_KEY, invocation.getMethodName()));
if (cache != null) {
String key = StringUtils.toArgumentString(invocation.getArguments());
if (cache != null && key != null) {
Object value = cache.get(key);
if (value != null) {
return new RpcResult(value);
}
Result result = invoker.invoke(invocation);
if (! result.hasException()) {
cache.put(key, result.getValue());
}
return result;
}
}
}
return invoker.invoke(invocation);
}
dubbo-filter-validation
同樣,利用Validator 的validate的方法, 如果校驗不過,直接報異常。
public Result invoke(Invoker<?> invoker, Invocation invocation) throws RpcException {
if (validation != null && ! invocation.getMethodName().startsWith("$")
&& ConfigUtils.isNotEmpty(invoker.getUrl().getMethodParameter(invocation.getMethodName(), Constants.VALIDATION_KEY))) {
try {
Validator validator = validation.getValidator(invoker.getUrl());
if (validator != null) {
validator.validate(invocation.getMethodName(), invocation.getParameterTypes(), invocation.getArguments());
}
} catch (RpcException e) {
throw e;
} catch (Throwable t) {
throw new RpcException(t.getMessage(), t);
}
}
return invoker.invoke(invocation);
}