java - 如何摆脱PlaceHistoryMapper

有没有办法不在Places中定义所有PlaceHistoryMapper？
此时，我使用Generator来自动生成所有位置的列表，但我不确定这是否正确。

public class AppPlaceHistoryMapper extends AbstractPlaceHistoryMapper<Object> {

    @Override
    protected PrefixAndToken getPrefixAndToken(Place place) {
        if (place instanceof AbstractPlace) {
            return new PrefixAndToken(((AbstractPlace) place).getName(), ((AbstractPlace) place).getTokenizer()
                    .getToken((AbstractPlace) place));
        }
        throw new RuntimeException("Invalid place: " + place);
    }

    /**
     * This method will be overrided by the gwt-generated class, so any changes made in it will not be executed
     *
     * @see PlaceMapperGenerator
     */
    @Override
    protected PlaceTokenizer<?> getTokenizer(String prefix) {
        AbstractPlace[] places = {/* List of places generated by PlaceMapperGenerator */};
        for (AbstractPlace p : places) {
            if (p.getName().equals(prefix)) {
                return p.getTokenizer();
            }
        }
        throw new RuntimeException("Unable to find place for provided prefix: " + prefix);
    }
}

发电机：

public class PlaceMapperGenerator extends Generator {

    // @formatter:off
    private static final String GENERATED_METHOD_TEMPLATE =
            "protected com.google.gwt.place.shared.PlaceTokenizer<?> getTokenizer(String prefix) {" +
                "AbstractPlace[] places = { %s };" +
                "for (AbstractPlace p : places) {" +
                    "if (p.getName().equals(prefix)) {" +
                        "return p.getTokenizer();" +
                    "}" +
                "}" +
                "throw new RuntimeException(\"Unable to find place for provided prefix: \" + prefix);" +
            "}"
    ; // @formatter:on

    @Override
    public String generate(TreeLogger logger, GeneratorContext context, String typeName) {
        JClassType type;
        try {
            type = context.getTypeOracle().getType(typeName);
        } catch (NotFoundException e) {
            throw new RuntimeException(e);
        }
        String implTypeName = type.getSimpleSourceName() + "Impl";
        String implPackageName = type.getPackage().getName();
        ClassSourceFileComposerFactory composerFactory = new ClassSourceFileComposerFactory(implPackageName,
                implTypeName);
        composerFactory.setSuperclass(AppPlaceHistoryMapper.class.getName());
        @SuppressWarnings("resource")
        PrintWriter printWriter = context.tryCreate(logger, implPackageName, implTypeName);
        if (printWriter != null) {
            SourceWriter sourceWriter = composerFactory.createSourceWriter(context, printWriter);
            sourceWriter.print(GENERATED_METHOD_TEMPLATE, getPlaces(context));
            sourceWriter.commit(logger);
            printWriter.close();
        }
        return composerFactory.getCreatedClassName();
    }

    private static String getPlaces(GeneratorContext context) {
        JPackage[] packages = context.getTypeOracle().getPackages();
        List<String> places = new ArrayList<String>();
        for (JPackage p : packages) {
            if (p.getName().startsWith(AbstractPlace.class.getPackage().getName())) {
                JClassType[] types = p.getTypes();
                for (JClassType type : types) {
                    if (type.getSuperclass() != null
                            && type.getSuperclass().getQualifiedSourceName().equals(AbstractPlace.class.getName())) {
                        places.add("new " + type.getQualifiedSourceName() + "()");
                    }
                }
            }
        }
        return places.toString().replaceAll("^\\[|\\]$", "");
    }
}

最佳答案

我担心，在不维护列表的情况下，找出应用程序中的位置和标记器的唯一方法是使用像您这样的生成器。
无论如何，我将使用@WithTokenizers注释，让gwt生成您的PlaceHistoryMapper来查看gwt mvpdev-guide

@WithTokenizers({HelloPlace.Tokenizer.class, GoodbyePlace.Tokenizer.class})
public interface AppPlaceHistoryMapper extends PlaceHistoryMapper {}

我在我的应用程序中所做的是使用一个脚本来生成活动、视图、位置，并基于模板更新gin模块和映射器。