private TypeName asyncDependencyType(DependencyRequest dependency) {
TypeName keyName = TypeNames.forTypeMirror(dependency.key().type());
switch (dependency.kind()) {
case INSTANCE:
return keyName;
case PRODUCED:
return ParameterizedTypeName.create(ClassName.fromClass(Produced.class), keyName);
default:
throw new AssertionError();
}
}
@Override
ImmutableSet<JavaWriter> write(ClassName generatedTypeName, ProductionBinding binding) {
TypeMirror keyType =
binding.productionType().equals(Type.MAP)
? Util.getProvidedValueTypeOfMap(MoreTypes.asDeclared(binding.key().type()))
: binding.key().type();
TypeName providedTypeName = TypeNames.forTypeMirror(keyType);
TypeName futureTypeName =
ParameterizedTypeName.create(ClassName.fromClass(ListenableFuture.class), providedTypeName);
JavaWriter writer = JavaWriter.inPackage(generatedTypeName.packageName());
ClassWriter factoryWriter = writer.addClass(generatedTypeName.simpleName());
ConstructorWriter constructorWriter = factoryWriter.addConstructor();
constructorWriter.addModifiers(PUBLIC);
factoryWriter.addField(binding.bindingTypeElement(), "module").addModifiers(PRIVATE, FINAL);
constructorWriter.addParameter(binding.bindingTypeElement(), "module");
constructorWriter
.body()
.addSnippet("assert module != null;")
.addSnippet("this.module = module;");
factoryWriter.addField(Executor.class, "executor").addModifiers(PRIVATE, FINAL);
constructorWriter.addParameter(Executor.class, "executor");
constructorWriter
.body()
.addSnippet("assert executor != null;")
.addSnippet("this.executor = executor;");
factoryWriter.annotate(Generated.class).setValue(ComponentProcessor.class.getName());
factoryWriter.addModifiers(PUBLIC);
factoryWriter.addModifiers(FINAL);
factoryWriter.setSuperclass(
ParameterizedTypeName.create(AbstractProducer.class, providedTypeName));
MethodWriter getMethodWriter = factoryWriter.addMethod(futureTypeName, "compute");
getMethodWriter.annotate(Override.class);
getMethodWriter.addModifiers(PROTECTED);
final ImmutableMap<BindingKey, FrameworkField> fields =
SourceFiles.generateBindingFieldsForDependencies(
dependencyRequestMapper, binding.dependencies());
for (FrameworkField bindingField : fields.values()) {
TypeName fieldType = bindingField.frameworkType();
FieldWriter field = factoryWriter.addField(fieldType, bindingField.name());
field.addModifiers(PRIVATE, FINAL);
constructorWriter.addParameter(field.type(), field.name());
constructorWriter
.body()
.addSnippet("assert %s != null;", field.name())
.addSnippet("this.%1$s = %1$s;", field.name());
}
boolean returnsFuture = binding.bindingKind().equals(ProductionBinding.Kind.FUTURE_PRODUCTION);
ImmutableList<DependencyRequest> asyncDependencies =
FluentIterable.from(binding.dependencies())
.filter(
new Predicate<DependencyRequest>() {
@Override
public boolean apply(DependencyRequest dependency) {
return isAsyncDependency(dependency);
}
})
.toList();
for (DependencyRequest dependency : asyncDependencies) {
ParameterizedTypeName futureType =
ParameterizedTypeName.create(
ClassName.fromClass(ListenableFuture.class), asyncDependencyType(dependency));
String name = fields.get(dependency.bindingKey()).name();
Snippet futureAccess = Snippet.format("%s.get()", name);
getMethodWriter
.body()
.addSnippet(
"%s %sFuture = %s;",
futureType,
name,
dependency.kind().equals(DependencyRequest.Kind.PRODUCED)
? Snippet.format(
"%s.createFutureProduced(%s)",
ClassName.fromClass(Producers.class), futureAccess)
: futureAccess);
}
if (asyncDependencies.isEmpty()) {
ImmutableList.Builder<Snippet> parameterSnippets = ImmutableList.builder();
for (DependencyRequest dependency : binding.dependencies()) {
parameterSnippets.add(
frameworkTypeUsageStatement(
Snippet.format(fields.get(dependency.bindingKey()).name()), dependency.kind()));
}
final boolean wrapWithFuture = false; // since submitToExecutor will create the future
Snippet invocationSnippet =
getInvocationSnippet(wrapWithFuture, binding, parameterSnippets.build());
TypeName callableReturnType = returnsFuture ? futureTypeName : providedTypeName;
Snippet throwsClause = getThrowsClause(binding.thrownTypes());
Snippet callableSnippet =
Snippet.format(
Joiner.on('\n')
.join(
"new %1$s<%2$s>() {",
" @Override public %2$s call() %3$s{", " return %4$s;", " }", "}"),
ClassName.fromClass(Callable.class),
callableReturnType,
throwsClause,
invocationSnippet);
getMethodWriter
.body()
.addSnippet(
"%s future = %s.submitToExecutor(%s, executor);",
ParameterizedTypeName.create(
ClassName.fromClass(ListenableFuture.class), callableReturnType),
ClassName.fromClass(Producers.class),
callableSnippet);
getMethodWriter
.body()
.addSnippet(
"return %s;",
returnsFuture
? Snippet.format("%s.dereference(future)", ClassName.fromClass(Futures.class))
: "future");
} else {
final Snippet futureSnippet;
final Snippet transformSnippet;
if (asyncDependencies.size() == 1) {
DependencyRequest asyncDependency = Iterables.getOnlyElement(asyncDependencies);
futureSnippet =
Snippet.format("%s", fields.get(asyncDependency.bindingKey()).name() + "Future");
String argName = asyncDependency.requestElement().getSimpleName().toString();
ImmutableList.Builder<Snippet> parameterSnippets = ImmutableList.builder();
for (DependencyRequest dependency : binding.dependencies()) {
// We really want to compare instances here, because asyncDependency is an element in the
// set binding.dependencies().
if (dependency == asyncDependency) {
parameterSnippets.add(Snippet.format("%s", argName));
} else {
parameterSnippets.add(
frameworkTypeUsageStatement(
Snippet.format(fields.get(dependency.bindingKey()).name()), dependency.kind()));
}
}
boolean wrapWithFuture = !returnsFuture; // only wrap if we don't already have a future
Snippet invocationSnippet =
getInvocationSnippet(wrapWithFuture, binding, parameterSnippets.build());
Snippet throwsClause = getThrowsClause(binding.thrownTypes());
transformSnippet =
Snippet.format(
Joiner.on('\n')
.join(
"new %1$s<%2$s, %3$s>() {",
" @Override public %4$s apply(%2$s %5$s) %6$s{",
" return %7$s;",
" }",
"}"),
ClassName.fromClass(AsyncFunction.class),
asyncDependencyType(asyncDependency),
providedTypeName,
futureTypeName,
argName,
throwsClause,
invocationSnippet);
} else {
futureSnippet =
Snippet.format(
"%s.<%s>allAsList(%s)",
ClassName.fromClass(Futures.class),
ClassName.fromClass(Object.class),
Joiner.on(",")
.join(
FluentIterable.from(asyncDependencies)
.transform(
new Function<DependencyRequest, String>() {
@Override
public String apply(DependencyRequest dependency) {
return fields.get(dependency.bindingKey()).name() + "Future";
}
})));
ImmutableList<Snippet> parameterSnippets = getParameterSnippets(binding, fields, "args");
boolean wrapWithFuture = !returnsFuture; // only wrap if we don't already have a future
Snippet invocationSnippet =
getInvocationSnippet(wrapWithFuture, binding, parameterSnippets);
ParameterizedTypeName listOfObject =
ParameterizedTypeName.create(
ClassName.fromClass(List.class), ClassName.fromClass(Object.class));
Snippet throwsClause = getThrowsClause(binding.thrownTypes());
transformSnippet =
Snippet.format(
Joiner.on('\n')
.join(
"new %1$s<%2$s, %3$s>() {",
" @SuppressWarnings(\"unchecked\") // safe by specification",
" @Override public %4$s apply(%2$s args) %5$s{",
" return %6$s;",
" }",
"}"),
ClassName.fromClass(AsyncFunction.class),
listOfObject,
providedTypeName,
futureTypeName,
throwsClause,
invocationSnippet);
}
getMethodWriter
.body()
.addSnippet(
"return %s.%s(%s, %s, executor);",
ClassName.fromClass(Futures.class), "transform", futureSnippet, transformSnippet);
}
// TODO(gak): write a sensible toString
return ImmutableSet.of(writer);
}