| // Copyright 2018 The Feed Authors. |
| // |
| // Licensed under the Apache License, Version 2.0 (the "License"); |
| // you may not use this file except in compliance with the License. |
| // You may obtain a copy of the License at |
| // |
| // http://www.apache.org/licenses/LICENSE-2.0 |
| // |
| // Unless required by applicable law or agreed to in writing, software |
| // distributed under the License is distributed on an "AS IS" BASIS, |
| // WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. |
| // See the License for the specific language governing permissions and |
| // limitations under the License. |
| |
| package com.google.android.libraries.feed.piet; |
| |
| import static com.google.search.now.ui.piet.ErrorsProto.ErrorCode.ERR_BINDING_VALUE_TYPE_MISMATCH; |
| import static com.google.search.now.ui.piet.ErrorsProto.ErrorCode.ERR_DUPLICATE_BINDING_VALUE; |
| import static com.google.search.now.ui.piet.ErrorsProto.ErrorCode.ERR_DUPLICATE_STYLE; |
| import static com.google.search.now.ui.piet.ErrorsProto.ErrorCode.ERR_DUPLICATE_TEMPLATE; |
| import static com.google.search.now.ui.piet.ErrorsProto.ErrorCode.ERR_MISSING_BINDING_VALUE; |
| import static com.google.search.now.ui.piet.ErrorsProto.ErrorCode.ERR_MISSING_TEMPLATE; |
| |
| import android.support.annotation.VisibleForTesting; |
| import android.view.View; |
| import com.google.android.libraries.feed.api.host.config.DebugBehavior; |
| import com.google.android.libraries.feed.common.logging.Logger; |
| import com.google.android.libraries.feed.piet.DebugLogger.MessageType; |
| import com.google.android.libraries.feed.piet.host.ActionHandler; |
| import com.google.android.libraries.feed.piet.host.HostBindingProvider; |
| import com.google.search.now.ui.piet.ActionsProto.Actions; |
| import com.google.search.now.ui.piet.BindingRefsProto.ActionsBindingRef; |
| import com.google.search.now.ui.piet.BindingRefsProto.ChunkedTextBindingRef; |
| import com.google.search.now.ui.piet.BindingRefsProto.CustomBindingRef; |
| import com.google.search.now.ui.piet.BindingRefsProto.ElementBindingRef; |
| import com.google.search.now.ui.piet.BindingRefsProto.GridCellWidthBindingRef; |
| import com.google.search.now.ui.piet.BindingRefsProto.ImageBindingRef; |
| import com.google.search.now.ui.piet.BindingRefsProto.LogDataBindingRef; |
| import com.google.search.now.ui.piet.BindingRefsProto.ParameterizedTextBindingRef; |
| import com.google.search.now.ui.piet.BindingRefsProto.StyleBindingRef; |
| import com.google.search.now.ui.piet.BindingRefsProto.TemplateBindingRef; |
| import com.google.search.now.ui.piet.BindingRefsProto.VisibilityBindingRef; |
| import com.google.search.now.ui.piet.ElementsProto.BindingContext; |
| import com.google.search.now.ui.piet.ElementsProto.BindingValue; |
| import com.google.search.now.ui.piet.ElementsProto.GridCellWidth; |
| import com.google.search.now.ui.piet.ElementsProto.Visibility; |
| import com.google.search.now.ui.piet.ErrorsProto.ErrorCode; |
| import com.google.search.now.ui.piet.ImagesProto.Image; |
| import com.google.search.now.ui.piet.ImagesProto.ImageSource; |
| import com.google.search.now.ui.piet.LogDataProto.LogData; |
| import com.google.search.now.ui.piet.PietProto.Frame; |
| import com.google.search.now.ui.piet.PietProto.PietSharedState; |
| import com.google.search.now.ui.piet.PietProto.Stylesheet; |
| import com.google.search.now.ui.piet.PietProto.Template; |
| import com.google.search.now.ui.piet.StylesProto.BoundStyle; |
| import com.google.search.now.ui.piet.StylesProto.Style; |
| import com.google.search.now.ui.piet.StylesProto.StyleIdsStack; |
| import java.util.ArrayList; |
| import java.util.Collections; |
| import java.util.HashMap; |
| import java.util.List; |
| import java.util.Map; |
| |
| /** |
| * This is a {@link FrameContext} that is bound. Binding means we have a {@code Frame}, an optional |
| * map of {@code BindingValues} and a {@code StyleProvider}. |
| */ |
| class FrameContext { |
| private static final String TAG = "FrameContext"; |
| |
| @VisibleForTesting final PietStylesHelper stylesHelper; |
| private final List<PietSharedState> pietSharedStates; |
| private final DebugBehavior debugBehavior; |
| private final DebugLogger debugLogger; |
| private final ActionHandler actionHandler; |
| private final HostProviders hostProviders; |
| private final HostBindingProvider hostBindingProvider; |
| private final Map<String, Template> templates; |
| |
| // List of stylesheets for each Template that could be affected by media queries. |
| private final Map<Template, List<Stylesheet>> templateMediaQueryStylesheets; |
| |
| // This is the Frame which contains all the slices being processed. |
| private final Frame currentFrame; |
| |
| // The Current Stylesheet as a map from style_id to Style. |
| private final Map<String, Style> stylesheet; |
| |
| // The in-scope bindings as a map from state_id to binding value |
| private final Map<String, BindingValue> bindingValues; |
| |
| // The base / default style; set to default instance for Frame or childDefaultStyleId for Template |
| private final Style baseStyle; |
| |
| // The root view of this frame. |
| private final View frameView; |
| |
| /** Initialize a FrameContext for the first time from a top-level Frame. */ |
| @VisibleForTesting |
| FrameContext( |
| Frame frame, |
| Map<String, Style> stylesheet, |
| List<PietSharedState> pietSharedStates, |
| PietStylesHelper pietStylesHelper, |
| DebugBehavior debugBehavior, |
| DebugLogger debugLogger, |
| ActionHandler actionHandler, |
| HostProviders hostProviders, |
| View frameView) { |
| this( |
| frame, |
| stylesheet, |
| new ThrowingEmptyMap(), |
| pietSharedStates, |
| pietStylesHelper, |
| debugBehavior, |
| debugLogger, |
| actionHandler, |
| hostProviders, |
| new NoKeyOverwriteHashMap<>("Template", ERR_DUPLICATE_TEMPLATE), |
| frameView); |
| |
| stylesHelper.addSharedStateTemplatesToFrame(templates); |
| if (frame.getTemplatesCount() > 0) { |
| for (Template template : frame.getTemplatesList()) { |
| if (pietStylesHelper.areMediaQueriesMet(template.getConditionsList())) { |
| templates.put(template.getTemplateId(), template); |
| } |
| } |
| } |
| } |
| |
| /** Set up a new FrameContext; typically called to copy an existing FrameContext. */ |
| FrameContext( |
| Frame frame, |
| Map<String, Style> stylesheet, |
| Map<String, BindingValue> bindingValues, |
| List<PietSharedState> pietSharedStates, |
| PietStylesHelper pietStylesHelper, |
| DebugBehavior debugBehavior, |
| DebugLogger debugLogger, |
| ActionHandler actionHandler, |
| HostProviders hostProviders, |
| Map<String, Template> templates, |
| View frameView) { |
| currentFrame = frame; |
| this.stylesheet = stylesheet; |
| this.bindingValues = bindingValues; |
| this.baseStyle = Style.getDefaultInstance(); |
| this.stylesHelper = pietStylesHelper; |
| this.pietSharedStates = pietSharedStates; |
| this.debugBehavior = debugBehavior; |
| this.debugLogger = debugLogger; |
| this.actionHandler = actionHandler; |
| this.hostProviders = hostProviders; |
| this.hostBindingProvider = hostProviders.getHostBindingProvider(); |
| this.templates = templates; |
| this.frameView = frameView; |
| this.templateMediaQueryStylesheets = new HashMap<>(); |
| } |
| |
| /** |
| * Creates a {@link FrameContext} and constructs the stylesheets from the frame and the list of |
| * {@link PietSharedState}. Any errors found with the styling will be reported. |
| */ |
| public static FrameContext createFrameContext( |
| Frame frame, |
| List<PietSharedState> pietSharedStates, |
| PietStylesHelper pietStylesHelper, |
| DebugBehavior debugBehavior, |
| DebugLogger debugLogger, |
| ActionHandler actionHandler, |
| HostProviders hostProviders, |
| View frameView) { |
| NoKeyOverwriteHashMap<String, Style> styleMap = null; |
| if (frame.hasStylesheets()) { |
| styleMap = pietStylesHelper.getStylesheetMap(frame.getStylesheets(), debugLogger); |
| } |
| |
| if (styleMap == null) { |
| styleMap = new NoKeyOverwriteHashMap<>("Style", ERR_DUPLICATE_STYLE); |
| } |
| return new FrameContext( |
| frame, |
| styleMap, |
| pietSharedStates, |
| pietStylesHelper, |
| debugBehavior, |
| debugLogger, |
| actionHandler, |
| hostProviders, |
| frameView); |
| } |
| |
| /** Return any of the template's stylesheets that could be affected by a MediaQuery. */ |
| List<Stylesheet> getMediaQueryStylesheets(Template template) { |
| if (templateMediaQueryStylesheets.containsKey(template)) { |
| return templateMediaQueryStylesheets.get(template); |
| } |
| |
| ArrayList<Stylesheet> mediaQueryStylesheets = new ArrayList<>(); |
| |
| for (Stylesheet stylesheet : template.getStylesheets().getStylesheetsList()) { |
| if (stylesheet.getConditionsCount() > 0) { |
| mediaQueryStylesheets.add(stylesheet); |
| } |
| } |
| for (String stylesheetId : template.getStylesheets().getStylesheetIdsList()) { |
| Stylesheet stylesheet = stylesHelper.getStylesheet(stylesheetId); |
| if (stylesheet != null && stylesheet.getConditionsCount() > 0) { |
| mediaQueryStylesheets.add(stylesheet); |
| } |
| } |
| |
| mediaQueryStylesheets.trimToSize(); |
| List<Stylesheet> mediaQueryStylesheetsImmutable = |
| Collections.unmodifiableList(mediaQueryStylesheets); |
| |
| templateMediaQueryStylesheets.put(template, mediaQueryStylesheetsImmutable); |
| |
| return mediaQueryStylesheetsImmutable; |
| } |
| |
| /** |
| * Creates a new FrameContext which is scoped properly for the Template. The Frame's stylesheet is |
| * discarded and replaced by the Template's stylesheet. In addition, a Template can define a root |
| * level style which applies to all child elements. |
| */ |
| FrameContext createTemplateContext(Template template, BindingContext bindingContext) { |
| Map<String, BindingValue> bindingValues = createBindingValueMap(bindingContext); |
| Map<String, Style> localStylesheet = |
| stylesHelper.getStylesheetMap(template.getStylesheets(), getDebugLogger()); |
| |
| return new FrameContext( |
| currentFrame, |
| localStylesheet, |
| bindingValues, |
| pietSharedStates, |
| stylesHelper, |
| debugBehavior, |
| debugLogger, |
| actionHandler, |
| hostProviders, |
| templates, |
| frameView); |
| } |
| |
| public DebugBehavior getDebugBehavior() { |
| return debugBehavior; |
| } |
| |
| public DebugLogger getDebugLogger() { |
| return debugLogger; |
| } |
| |
| public Frame getFrame() { |
| return currentFrame; |
| } |
| |
| public ActionHandler getActionHandler() { |
| return actionHandler; |
| } |
| |
| public Template getTemplate(String templateId) { |
| Template template = templates.get(templateId); |
| if (template == null) { |
| throw new PietFatalException( |
| ERR_MISSING_TEMPLATE, |
| reportMessage( |
| MessageType.ERROR, |
| ERR_MISSING_TEMPLATE, |
| String.format("Template '%s' not found", templateId))); |
| } |
| return template; |
| } |
| |
| public List<PietSharedState> getPietSharedStates() { |
| return pietSharedStates; |
| } |
| |
| /** Return a {@link StyleProvider} for the style. */ |
| public StyleProvider makeStyleFor(StyleIdsStack styles) { |
| return new StyleProvider( |
| PietStylesHelper.mergeStyleIdsStack(baseStyle, styles, stylesheet, this), |
| hostProviders.getAssetProvider()); |
| } |
| |
| /** |
| * Return a {@link GridCellWidth} for the binding if there is one defined; otherwise returns |
| * {@code null}. |
| */ |
| /*@Nullable*/ |
| GridCellWidth getGridCellWidthFromBinding(GridCellWidthBindingRef binding) { |
| BindingValue bindingValue = bindingValues.get(binding.getBindingId()); |
| // Purposefully check for host binding and overwrite here as we want to perform the hasCellWidth |
| // checks on host binding. This allows the host to act more like the server. |
| if (bindingValue != null && bindingValue.hasHostBindingData()) { |
| bindingValue = hostBindingProvider.getGridCellWidthBindingForValue(bindingValue); |
| } |
| return bindingValue == null || !bindingValue.hasCellWidth() |
| ? null |
| : bindingValue.getCellWidth(); |
| } |
| |
| /** |
| * Return an {@link Actions} for the binding if there is one defined; otherwise returns the |
| * default instance. |
| */ |
| Actions getActionsFromBinding(ActionsBindingRef binding) { |
| BindingValue bindingValue = bindingValues.get(binding.getBindingId()); |
| if (bindingValue != null && bindingValue.hasHostBindingData()) { |
| bindingValue = hostBindingProvider.getActionsBindingForValue(bindingValue); |
| } |
| if (bindingValue == null) { |
| return Actions.getDefaultInstance(); |
| } |
| if (!bindingValue.hasActions()) { |
| Logger.w( |
| TAG, |
| reportMessage( |
| MessageType.WARNING, |
| ERR_BINDING_VALUE_TYPE_MISMATCH, |
| String.format("No actions found for binding %s", binding.getBindingId()))); |
| } |
| return bindingValue.getActions(); |
| } |
| |
| /** |
| * Return a {@link BoundStyle} for the binding if there is one defined; otherwise returns the |
| * default instance. |
| */ |
| BoundStyle getStyleFromBinding(StyleBindingRef binding) { |
| return getStyleFromBinding(binding, bindingValues); |
| } |
| |
| /** |
| * Return a {@link BoundStyle} for the binding if there is one defined; otherwise returns the |
| * default instance. |
| */ |
| BoundStyle getStyleFromBinding(StyleBindingRef binding, Map<String, BindingValue> bindingValues) { |
| BindingValue bindingValue = bindingValues.get(binding.getBindingId()); |
| if (bindingValue != null && bindingValue.hasHostBindingData()) { |
| bindingValue = hostBindingProvider.getStyleBindingForValue(bindingValue); |
| } |
| if (bindingValue == null) { |
| return BoundStyle.getDefaultInstance(); |
| } |
| if (!bindingValue.hasBoundStyle()) { |
| Logger.w( |
| TAG, |
| reportMessage( |
| MessageType.WARNING, |
| ERR_BINDING_VALUE_TYPE_MISMATCH, |
| String.format("No style found for binding %s", binding.getBindingId()))); |
| } |
| return bindingValue.getBoundStyle(); |
| } |
| |
| /** Returns the {@link BindingValue} for the BindingRef; otherwise returns null. */ |
| /*@Nullable*/ |
| Visibility getVisibilityFromBinding(VisibilityBindingRef binding) { |
| BindingValue bindingValue = bindingValues.get(binding.getBindingId()); |
| if (bindingValue != null && bindingValue.hasHostBindingData()) { |
| bindingValue = hostBindingProvider.getVisibilityBindingForValue(bindingValue); |
| } |
| if (bindingValue == null) { |
| return null; |
| } else if (!bindingValue.hasVisibility()) { |
| Logger.w( |
| TAG, |
| reportMessage( |
| MessageType.WARNING, |
| ERR_BINDING_VALUE_TYPE_MISMATCH, |
| String.format("No visibility found for binding %s", binding.getBindingId()))); |
| return null; |
| } else { |
| return bindingValue.getVisibility(); |
| } |
| } |
| |
| Image filterImageSourcesByMediaQueryCondition(Image image) { |
| Image.Builder imageBuilder = image.toBuilder().clearSources(); |
| for (ImageSource source : image.getSourcesList()) { |
| if (stylesHelper.areMediaQueriesMet(source.getConditionsList())) { |
| imageBuilder.addSources(source); |
| } |
| } |
| return imageBuilder.build(); |
| } |
| |
| /** |
| * Returns the {@link BindingValue} for the BindingRef; throws IllegalStateException if binding id |
| * does not point to a template resource. |
| */ |
| BindingValue getTemplateInvocationBindingValue(TemplateBindingRef binding) { |
| BindingValue bindingValue = getBindingValue(binding.getBindingId()); |
| if (bindingValue.hasHostBindingData()) { |
| bindingValue = hostBindingProvider.getTemplateBindingForValue(bindingValue); |
| } |
| if (!bindingValue.hasTemplateInvocation() && !binding.getIsOptional()) { |
| throw new PietFatalException( |
| ERR_MISSING_BINDING_VALUE, |
| reportMessage( |
| MessageType.ERROR, |
| ERR_MISSING_BINDING_VALUE, |
| String.format("Template binding not found for %s", binding.getBindingId()))); |
| } else { |
| return bindingValue; |
| } |
| } |
| |
| /** |
| * Returns the {@link BindingValue} for the BindingRef; throws IllegalStateException if binding id |
| * does not point to a custom element resource. |
| */ |
| BindingValue getCustomElementBindingValue(CustomBindingRef binding) { |
| BindingValue bindingValue = getBindingValue(binding.getBindingId()); |
| if (bindingValue.hasHostBindingData()) { |
| bindingValue = hostBindingProvider.getCustomElementDataBindingForValue(bindingValue); |
| } |
| if (!bindingValue.hasCustomElementData() && !binding.getIsOptional()) { |
| throw new PietFatalException( |
| ERR_MISSING_BINDING_VALUE, |
| reportMessage( |
| MessageType.ERROR, |
| ERR_MISSING_BINDING_VALUE, |
| String.format("Custom element binding not found for %s", binding.getBindingId()))); |
| } else { |
| return bindingValue; |
| } |
| } |
| |
| /** |
| * Returns the {@link BindingValue} for the BindingRef; throws IllegalStateException if binding id |
| * does not point to a chunked text resource. |
| */ |
| BindingValue getChunkedTextBindingValue(ChunkedTextBindingRef binding) { |
| BindingValue bindingValue = getBindingValue(binding.getBindingId()); |
| if (bindingValue.hasHostBindingData()) { |
| bindingValue = hostBindingProvider.getChunkedTextBindingForValue(bindingValue); |
| } |
| if (!bindingValue.hasChunkedText() && !binding.getIsOptional()) { |
| throw new PietFatalException( |
| ERR_MISSING_BINDING_VALUE, |
| reportMessage( |
| MessageType.ERROR, |
| ERR_MISSING_BINDING_VALUE, |
| String.format("Chunked text binding not found for %s", binding.getBindingId()))); |
| } else { |
| return bindingValue; |
| } |
| } |
| |
| /** |
| * Returns the {@link BindingValue} for the BindingRef; throws IllegalStateException if binding id |
| * does not point to a parameterized text resource. |
| */ |
| BindingValue getParameterizedTextBindingValue(ParameterizedTextBindingRef binding) { |
| BindingValue bindingValue = getBindingValue(binding.getBindingId()); |
| if (bindingValue.hasHostBindingData()) { |
| bindingValue = hostBindingProvider.getParameterizedTextBindingForValue(bindingValue); |
| } |
| if (!bindingValue.hasParameterizedText() && !binding.getIsOptional()) { |
| throw new PietFatalException( |
| ERR_MISSING_BINDING_VALUE, |
| reportMessage( |
| MessageType.ERROR, |
| ERR_MISSING_BINDING_VALUE, |
| String.format( |
| "Parameterized text binding not found for %s", binding.getBindingId()))); |
| } else { |
| return bindingValue; |
| } |
| } |
| |
| /** |
| * Returns the {@link BindingValue} for the BindingRef; throws IllegalStateException if binding id |
| * does not point to a image resource. |
| */ |
| BindingValue getImageBindingValue(ImageBindingRef binding) { |
| BindingValue bindingValue = getBindingValue(binding.getBindingId()); |
| if (bindingValue.hasHostBindingData()) { |
| bindingValue = hostBindingProvider.getImageBindingForValue(bindingValue); |
| } |
| if (!bindingValue.hasImage() && !binding.getIsOptional()) { |
| throw new PietFatalException( |
| ERR_MISSING_BINDING_VALUE, |
| reportMessage( |
| MessageType.ERROR, |
| ERR_MISSING_BINDING_VALUE, |
| String.format("Image binding not found for %s", binding.getBindingId()))); |
| } else { |
| return bindingValue; |
| } |
| } |
| |
| /** |
| * Returns the {@link BindingValue} for the BindingRef; throws IllegalStateException if binding id |
| * does not point to an Element. |
| */ |
| BindingValue getElementBindingValue(ElementBindingRef binding) { |
| BindingValue bindingValue = getBindingValue(binding.getBindingId()); |
| if (bindingValue.hasHostBindingData()) { |
| bindingValue = hostBindingProvider.getElementBindingForValue(bindingValue); |
| } |
| if (!bindingValue.hasElement() && !binding.getIsOptional()) { |
| throw new PietFatalException( |
| ERR_MISSING_BINDING_VALUE, |
| reportMessage( |
| MessageType.ERROR, |
| ERR_MISSING_BINDING_VALUE, |
| String.format("Element binding not found for %s", binding.getBindingId()))); |
| } else { |
| return bindingValue; |
| } |
| } |
| |
| /** |
| * Return an {@link LogData} for the binding if there is one defined; otherwise returns the |
| * default instance. |
| */ |
| /*@Nullable*/ |
| LogData getLogDataFromBinding(LogDataBindingRef binding) { |
| BindingValue bindingValue = bindingValues.get(binding.getBindingId()); |
| if (bindingValue != null && bindingValue.hasHostBindingData()) { |
| bindingValue = hostBindingProvider.getLogDataBindingForValue(bindingValue); |
| } |
| if (bindingValue == null) { |
| return null; |
| } |
| if (!bindingValue.hasLogData()) { |
| Logger.w( |
| TAG, |
| reportMessage( |
| MessageType.WARNING, |
| ERR_BINDING_VALUE_TYPE_MISMATCH, |
| String.format("No logData found for binding %s", binding.getBindingId()))); |
| return null; |
| } |
| return bindingValue.getLogData(); |
| } |
| |
| /** Returns the root view of this Frame. */ |
| View getFrameView() { |
| return frameView; |
| } |
| |
| private BindingValue getBindingValue(String bindingId) { |
| BindingValue returnValue = bindingValues.get(bindingId); |
| if (returnValue == null) { |
| return BindingValue.getDefaultInstance(); |
| } |
| return returnValue; |
| } |
| |
| /** |
| * Report user errors in frames. This will return the fully formed error so it can be logged at |
| * the site of the error. |
| */ |
| public String reportMessage(@MessageType int messageType, String message) { |
| String e = String.format("[%s] %s", currentFrame.getTag(), message); |
| debugLogger.recordMessage(messageType, e); |
| return e; |
| } |
| |
| /** |
| * Report user errors in frames. This will return the fully formed error so it can be logged at |
| * the site of the error. |
| */ |
| public String reportMessage(@MessageType int messageType, ErrorCode errorCode, String message) { |
| String e = String.format("[%s] %s", currentFrame.getTag(), message); |
| debugLogger.recordMessage(messageType, errorCode, e); |
| return e; |
| } |
| |
| private Map<String, BindingValue> createBindingValueMap(BindingContext bindingContext) { |
| Map<String, BindingValue> bindingValueMap = |
| new NoKeyOverwriteHashMap<>("BindingValue", ERR_DUPLICATE_BINDING_VALUE); |
| for (BindingValue bindingValue : bindingContext.getBindingValuesList()) { |
| if (bindingValue.hasBindingIdFromTranscludingTemplate()) { |
| BindingValue parentBindingValue = |
| bindingValues.get(bindingValue.getBindingIdFromTranscludingTemplate()); |
| if (parentBindingValue == null) { |
| reportMessage( |
| MessageType.ERROR, |
| ERR_MISSING_BINDING_VALUE, |
| String.format( |
| "Parent binding value '%s' not found", |
| bindingValue.getBindingIdFromTranscludingTemplate())); |
| } else { |
| BindingValue bindingValueForChild = |
| parentBindingValue.toBuilder().setBindingId(bindingValue.getBindingId()).build(); |
| bindingValueMap.put(bindingValue.getBindingId(), bindingValueForChild); |
| } |
| } else { |
| bindingValueMap.put(bindingValue.getBindingId(), bindingValue); |
| } |
| } |
| return bindingValueMap; |
| } |
| |
| /** Map that throws whenever you try to look anything up in it. */ |
| private static class ThrowingEmptyMap extends HashMap<String, BindingValue> { |
| @Override |
| public BindingValue get(/*@Nullable*/ Object key) { |
| throw new PietFatalException( |
| ErrorCode.ERR_MISSING_BINDING_VALUE, |
| "Looking up bindings not supported in this context; no BindingValues defined."); |
| } |
| } |
| } |
