/*
* Copyright 2013 Google Inc.
*
* 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.gwt.dev.cfg;
import com.google.gwt.core.ext.Generator;
import com.google.gwt.core.ext.GeneratorContext;
import com.google.gwt.core.ext.TreeLogger;
import com.google.gwt.core.ext.UnableToCompleteException;
import com.google.gwt.core.ext.linker.PropertyProviderGenerator;
import com.google.gwt.core.ext.linker.impl.StandardConfigurationProperty;
import com.google.gwt.core.ext.linker.impl.StandardLinkerContext;
import com.google.gwt.dev.jjs.InternalCompilerException;
import com.google.gwt.thirdparty.guava.common.collect.Lists;
import com.google.gwt.thirdparty.guava.common.collect.Sets;
import java.io.PrintWriter;
import java.util.ArrayList;
import java.util.Arrays;
import java.util.Collection;
import java.util.List;
import java.util.Map.Entry;
import java.util.Set;
import java.util.SortedSet;
import java.util.TreeSet;
/**
* Generator used to generate a class unique to the current module which has a register() function
* that when invoked will register the given property provider implementations with a global
* registry.<br />
*
* The resulting class is expected to be invoked at runtime as part of per module bootstrapping and
* before anything that might depend on property lookups (like GWT.create() calls).
*/
public class PropertyProviderRegistratorGenerator extends Generator {
/**
* The extension for all generated property provider registrator classes. Is exposed publicly so
* others can filter using the extension.
*/
public static final String PROPERTY_PROVIDER_REGISTRATOR_SUFFIX =
"PropertyProviderRegistrator";
private static final String PACKAGE_PATH = "com.google.gwt.lang";
private static SortedSet<com.google.gwt.core.ext.linker.ConfigurationProperty> toLinkerStyle(
SortedSet<ConfigurationProperty> configurationProperties) {
SortedSet<com.google.gwt.core.ext.linker.ConfigurationProperty> linkerConfigurationProperties =
new TreeSet<com.google.gwt.core.ext.linker.ConfigurationProperty>(
StandardLinkerContext.CONFIGURATION_PROPERTY_COMPARATOR);
for (ConfigurationProperty configurationProperty : configurationProperties) {
linkerConfigurationProperties.add(new StandardConfigurationProperty(configurationProperty));
}
return linkerConfigurationProperties;
}
private SortedSet<com.google.gwt.core.ext.linker.ConfigurationProperty> configurationProperties;
private Collection<BindingProperty> newBindingProperties;
private Set<String> propertyProviderClassNames = Sets.newHashSet();
/**
* Constructs a PropertyProviderRegistratorGenerator that is able to generate a property provider
* registrator for all of the given a collection of binding properties.<br />
*
* The provided binding properties are expected to all have been created by the current module but
* the provided configuration properties should be all that have been created by the entire
* current dependency tree.
*/
public PropertyProviderRegistratorGenerator(Collection<BindingProperty> newBindingProperties,
SortedSet<ConfigurationProperty> configurationProperties) {
this.newBindingProperties = newBindingProperties;
this.configurationProperties = toLinkerStyle(configurationProperties);
}
@Override
public String generate(TreeLogger logger, GeneratorContext context, String moduleName)
throws UnableToCompleteException {
String typeName = moduleName.replace(".", "_").replace("-", "_") + "_"
+ PROPERTY_PROVIDER_REGISTRATOR_SUFFIX;
PrintWriter out = context.tryCreate(logger, PACKAGE_PATH, typeName);
if (out != null) {
out.println("package " + PACKAGE_PATH + ";");
out.println("import com.google.gwt.lang.RuntimePropertyRegistry;");
out.println(
"import com.google.gwt.lang.RuntimePropertyRegistry.PropertyValueProvider;");
out.println("public class " + typeName + " {");
for (BindingProperty bindingProperty : newBindingProperties) {
// If nothing about the binding property was set or created in the current module.
if (bindingProperty.getTargetLibraryDefinedValues().isEmpty()) {
// Then its previously created property provider is still valid.
continue;
}
createPropertyProviderClass(logger, out, bindingProperty);
}
// TODO(stalcup): create configuration property providers.
out.println(" public static void register() {");
for (String propertyProviderClassName : propertyProviderClassNames) {
out.println(" RuntimePropertyRegistry.registerPropertyValueProvider(new "
+ propertyProviderClassName + "());");
}
// TODO(stalcup): register configuration property providers.
out.println(" }");
out.println("}");
context.commit(logger, out);
} else {
// Must have been a cache hit.
}
return PACKAGE_PATH + "." + typeName;
}
private void createConditionTreeGetter(PrintWriter out, BindingProperty bindingProperty) {
List<Entry<Condition, SortedSet<String>>> entries = new ArrayList<
Entry<Condition, SortedSet<String>>>(bindingProperty.getConditionalValues().entrySet());
List<Entry<Condition, SortedSet<String>>> prioritizedEntries = Lists.reverse(entries);
out.println(" public native String getValue() /*-{");
boolean alwaysReturnsAValue = false;
for (Entry<Condition, SortedSet<String>> entry : prioritizedEntries) {
Condition condition = entry.getKey();
SortedSet<String> propertyValue = entry.getValue();
String conditionSource = condition.toSource();
if (!conditionSource.isEmpty() && !conditionSource.equals("true")) {
out.println(" if (" + conditionSource + ") {");
out.println(" return \"" + propertyValue.iterator().next() + "\";");
out.println(" }");
} else {
alwaysReturnsAValue = true;
out.println(" return \"" + propertyValue.iterator().next() + "\";");
}
}
if (!alwaysReturnsAValue) {
out.println(" throw @java.lang.RuntimeException::new(Ljava/lang/String;)"
+ "(\"No known value for property " + bindingProperty.getName() + "\");");
}
out.println(" }-*/;");
}
private void createConstrainedValueGetter(PrintWriter out, BindingProperty bindingProperty) {
out.println(" public String getValue() {");
out.println(" return \"" + bindingProperty.getConstrainedValue() + "\";");
out.println(" }");
}
private void createPropertyProviderClass(
TreeLogger logger, PrintWriter out, BindingProperty bindingProperty) {
String bindingPropertyClassName = "PropertyValueProvider" + propertyProviderClassNames.size();
propertyProviderClassNames.add(bindingPropertyClassName);
out.println(
" private static class " + bindingPropertyClassName + " extends PropertyValueProvider {");
out.println(" public String getName() {");
out.println(" return \"" + bindingProperty.getName() + "\";");
out.println(" }");
// There are four different ways that modules can register the runtime provider for binding
// properties and the order of precedence is very particular and important.
if (bindingProperty.getConstrainedValue() != null) {
createConstrainedValueGetter(out, bindingProperty);
} else if (bindingProperty.isDerived()) {
createConditionTreeGetter(out, bindingProperty);
} else if (bindingProperty.getProviderGenerator() != null) {
createPropertyProviderGeneratorGetter(logger, out, bindingProperty);
} else if (bindingProperty.getProvider() != null) {
createProviderGetter(out, bindingProperty);
} else {
throw new InternalCompilerException("Failed to locate the runtime provider for "
+ "binding property '" + bindingProperty.getName() + "'");
}
out.println(" }");
}
private void createPropertyProviderGeneratorGetter(
TreeLogger logger, PrintWriter out, BindingProperty bindingProperty) {
out.print(" public native String getValue() /*-");
out.print(generateValue(logger, bindingProperty).trim());
out.println("-*/;");
}
private void createProviderGetter(PrintWriter out, BindingProperty bindingProperty) {
out.print(" public native String getValue() /*-");
out.print(bindingProperty.getProvider().getBody().trim());
out.print("-*/;");
}
private String generateValue(TreeLogger logger, BindingProperty bindingProperty) {
PropertyProviderGenerator propertyProviderGenerator;
try {
propertyProviderGenerator = bindingProperty.getProviderGenerator().newInstance();
} catch (IllegalAccessException e) {
throw new InternalCompilerException("Failed to instantiate property provider generator "
+ bindingProperty.getProviderGenerator());
} catch (InstantiationException e) {
throw new InternalCompilerException("Failed to instantiate property provider generator "
+ bindingProperty.getProviderGenerator());
}
try {
return propertyProviderGenerator.generate(logger,
Sets.newTreeSet(Arrays.asList(bindingProperty.getDefinedValues())),
bindingProperty.getFallback(), configurationProperties);
} catch (UnableToCompleteException e) {
throw new InternalCompilerException("Failed to run property provider generator "
+ bindingProperty.getProviderGenerator());
}
}
}