assertTrue(transformer.isValidUrl("http://www.example.com"));
        assertTrue(transformer.isValidUrl("http://www.example.com/aaa"));
        assertTrue(transformer.isValidUrl("https://www.example.com"));
        assertTrue(transformer.isValidUrl("://www.example.com"));
        assertTrue(transformer.isValidUrl("//www.example.com"));

        assertFalse(transformer.isValidUrl(null));

<!DOCTYPE components PUBLIC "-//DBFLUTE//DTD LastaDi 1.0//EN"
	"http://dbflute.org/meta/lastadi10.dtd">
<components namespace="fessCrawler">
	<include path="crawler/container.xml" />
	<include path="crawler/transformer.xml" />

	<component name="ruleManager" class="org.codelibs.fess.crawler.rule.impl.RuleManagerImpl" instance="prototype">
		<postConstruct name="addRule">
			<arg>sitemapsRule</arg>
		</postConstruct>

    // objectKeyed = transformEntries(map6, transformer);
    // objectKeyed = transformEntries(map8, transformer);
    // objectKeyed = transformEntries(map9, transformer);
    // numberKeyed = transformEntries(map8, transformer);
    // numberKeyed = transformEntries(map9, transformer);

    // Can't loosen the value type:
    // Map<Number, Number> looseValued1 = transformEntries(map5, transformer);

    TransformedEntriesMap(
        Map<K, V1> fromMap, EntryTransformer<? super K, ? super V1, V2> transformer) {
      this.fromMap = checkNotNull(fromMap);
      this.transformer = checkNotNull(transformer);
    }

    @Override
    public int size() {
      return fromMap.size();
    }

    @Override
    public boolean containsKey(@Nullable Object key) {

    TransformedEntriesMap(
        Map<K, V1> fromMap, EntryTransformer<? super K, ? super V1, V2> transformer) {
      this.fromMap = checkNotNull(fromMap);
      this.transformer = checkNotNull(transformer);
    }

    @Override
    public int size() {
      return fromMap.size();
    }

    @Override
    public boolean containsKey(@Nullable Object key) {

```

### Key Design Patterns

- **Factory**: `CrawlerClientFactory`, `ExtractorFactory` - protocol/format-specific component selection
- **Strategy**: `CrawlerClient`, `Extractor`, `Transformer` - pluggable implementations
- **Builder**: `RequestDataBuilder`, `ExtractorBuilder` - fluent construction
- **Template Method**: `AbstractCrawlerClient`, `AbstractExtractor` - common logic with overrides

        output.cancel(false);
        throw new SomeUncheckedException();
      }
    }
    Transformer transformer = new Transformer();
    SettableFuture<Object> input = SettableFuture.create();

    ListenableFuture<Object> output = transform(input, transformer, directExecutor());
    transformer.output = output;

    input.set("foo");
    assertTrue(output.isCancelled());
  }

        output.cancel(false);
        throw new SomeUncheckedException();
      }
    }
    Transformer transformer = new Transformer();
    SettableFuture<Object> input = SettableFuture.create();

    ListenableFuture<Object> output = transform(input, transformer, directExecutor());
    transformer.output = output;

    input.set("foo");
    assertTrue(output.isCancelled());
  }

Existing Groovy methods will not be removed immediately.

## Consequences

* If we would have used `Closure`, we must instead use `Action<T>`, `Spec<T>`, `Callable<T>`, or `Transformer<OUT, IN>`.
* We need to ensure all APIs that are exposed in the Groovy DSL go through runtime decoration.
Runtime decoration mixes in methods that use Groovy Closures to maintain consistent behavior in Groovy DSL.

                        + responseProcessor + ", url: " + url);
            }
            final Transformer transformer = ((DefaultResponseProcessor) responseProcessor).getTransformer();
            final ResultData resultData = transformer.transform(responseData);
            final Object rawData = resultData.getRawData();
            if (rawData != null) {