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1 – InterceptorProcessor ARouter to explain
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2 – AutowiredProcessor ARouter interpretation
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3 _routeprocessor ARouter interpretation
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4 _core Arouter explanation
Autowired
@Target({ElementType.FIELD})
@Retention(RetentionPolicy.CLASS)
public @interface Autowired {
// Mark param's name or service name.
String name(a) default "";
// If required, app will be crash when value is null.
// Primitive type wont be check!
boolean required(a) default false;
// Description of the field
String desc(a) default "";
}
Copy the codeAn overview of the
The use of Autowired is to inject fields, or else use methods like getIntent().getintextra (). This will also generate a new class in which the injected operations will operate. Like the following classes
Break down
The 1-interceptorProcessor is provided by the ARouter InterceptorProcessor, but it is also provided by the ARouter InterceptorProcessor. The 1-interceptorProcessor is provided by the ARouter InterceptorProcessor, but it is also provided by the ARouter InterceptorProcessor.
// Autowired annotations are applied to fields in a class or interface, where the key in the HashMap is the class or interface and the value is the Autowired annotated element in the class
private Map<TypeElement, List<Element>> parentAndChild = new HashMap<>();
public boolean process(Set<? extends TypeElement> set, RoundEnvironment roundEnvironment) {
if (CollectionUtils.isNotEmpty(set)) {
try {
this.categories(roundEnvironment.getElementsAnnotatedWith(Autowired.class));
this.generateHelper();
} catch (Exception var4) {
this.logger.error(var4);
}
return true;
} else {
return false; }}// Elements in the method are field elements, which are usually in the class or interface
private void categories(Set<? extends Element> elements) throws IllegalAccessException {
if (CollectionUtils.isNotEmpty(elements)) {
for (Element element : elements) {
// Get the class or interface of this field
TypeElement enclosingElement = (TypeElement) element.getEnclosingElement();
// This class or interface cannot be private
if (element.getModifiers().contains(Modifier.PRIVATE)) {
throw new IllegalAccessException("The inject fields CAN NOT BE 'private'!!! please check field ["
+ element.getSimpleName() + "] in class [" + enclosingElement.getQualifiedName() + "]");
}
if (parentAndChild.containsKey(enclosingElement)) { // Has categries
parentAndChild.get(enclosingElement).add(element);
} else {
List<Element> childs = new ArrayList<>();
childs.add(element);
parentAndChild.put(enclosingElement, childs);
}
}
logger.info("categories finished."); }}Copy the code
ParentAndChild is a collection of all Autowired annotated fields in a class.
package com.alibaba.android.arouter.facade.template;
public interface ISyringe {
void inject(Object target);
}
Copy the codeprivate void generateHelper(a) throws IOException, IllegalAccessException {
// Prepare some elements first
// com.alibaba.android.arouter.facade.template.ISyringe
TypeElement type_ISyringe = elementUtils.getTypeElement(ISYRINGE);
/ / com. Alibaba. Android. Arouter. Facade. Service. This is a IProvider SerializationService, behind us
TypeElement type_JsonService = elementUtils.getTypeElement(JSON_SERVICE);
// com.alibaba.android.arouter.facade.template.IProvider
TypeMirror iProvider = elementUtils.getTypeElement(Consts.IPROVIDER).asType();
// android.app.Activity
TypeMirror activityTm = elementUtils.getTypeElement(Consts.ACTIVITY).asType();
// android.app.Fragment
TypeMirror fragmentTm = elementUtils.getTypeElement(Consts.FRAGMENT).asType();
// android.support.v4.app.Fragment
TypeMirror fragmentTmV4 = elementUtils.getTypeElement(Consts.FRAGMENT_V4).asType();
// Build input param name.
// The method parameter type and parameter name
ParameterSpec objectParamSpec = ParameterSpec.builder(TypeName.OBJECT, "target").build();
if (MapUtils.isNotEmpty(parentAndChild)) {
// Iterate over a field with an Autowired annotation inside each class
for (Map.Entry<TypeElement, List<Element>> entry : parentAndChild.entrySet()) {
// Build method : 'inject'
// Build a method, public void inject(Object target)
MethodSpec.Builder injectMethodBuilder = MethodSpec.methodBuilder(METHOD_INJECT)
.addAnnotation(Override.class)
.addModifiers(PUBLIC)
.addParameter(objectParamSpec);
TypeElement parent = entry.getKey();
List<Element> childs = entry.getValue();
// The fully qualified name of the class
String qualifiedName = parent.getQualifiedName().toString();
// Class package name
String packageName = qualifiedName.substring(0, qualifiedName.lastIndexOf("."));
$$ARouter$$Autowired $$ARouter$$Autowired
String fileName = parent.getSimpleName() + NAME_OF_AUTOWIRED;
// Build a class that implements the ISyringe interface. Access is public
TypeSpec.Builder helper = TypeSpec.classBuilder(fileName)
.addJavadoc(WARNING_TIPS)
.addSuperinterface(ClassName.get(type_ISyringe))
.addModifiers(PUBLIC);
// Add a member variable serializationService
FieldSpec jsonServiceField = FieldSpec.builder(TypeName.get(type_JsonService.asType()), "serializationService", Modifier.PRIVATE).build();
helper.addField(jsonServiceField);
// Inside the inject method
// serializationService = ARouter.getInstance().navigation(SerializationService.class);
// serializationService serializes objects and converts them to JSON for delivery
injectMethodBuilder.addStatement("serializationService = $T.getInstance().navigation($T.class)", ARouterClass, ClassName.get(type_JsonService));
injectMethodBuilder.addStatement("$T substitute = ($T)target", ClassName.get(parent), ClassName.get(parent));
// Generate method body, start inject.
for (Element element : childs) {
Autowired fieldConfig = element.getAnnotation(Autowired.class);
// The element name
String fieldName = element.getSimpleName().toString();
if (types.isSubtype(element.asType(), iProvider)) { // It's provider
If element is a subclass of IProvider
if ("".equals(fieldConfig.name())) { // User has not set service path, then use byType.
// Getter
// substitute.{fieldName} = arouter.getInstance ().navigation({elementClass}.class),{} indicates placeholder
injectMethodBuilder.addStatement(
"substitute." + fieldName + " = $T.getInstance().navigation($T.class)",
ARouterClass,
ClassName.get(element.asType())
);
} else { // use byName
// Getter
// substitute.{fieldName} =({elementClass}) ARouter.getInstance().build({ConfigName}).navigation()
injectMethodBuilder.addStatement(
"substitute." + fieldName + " = ($T)$T.getInstance().build($S).navigation()",
ClassName.get(element.asType()),
ARouterClass,
fieldConfig.name()
);
}
// Validator
if (fieldConfig.required()) {
// If required is true, check for null after injection
injectMethodBuilder.beginControlFlow("if (substitute." + fieldName + " == null)");
injectMethodBuilder.addStatement(
"throw new RuntimeException(\"The field '" + fieldName + "' is null, in class '\" + $T.class.getName() + \"! \ ")", ClassName.get(parent)); injectMethodBuilder.endControlFlow(); }}else { // It's normal intent value
String originalValue = "substitute." + fieldName;
String statement = "substitute." + fieldName + "=" + buildCastCode(element) + "substitute.";
boolean isActivity = false;
if (types.isSubtype(parent.asType(), activityTm)) { // Activity, then use getIntent()
Age = substitute. GetIntent (). GetIntExtra ("age", substitute. Age);
isActivity = true;
statement += "getIntent().";
} else if (types.isSubtype(parent.asType(), fragmentTm) || types.isSubtype(parent.asType(), fragmentTmV4)) { // Fragment, then use getArguments()
// Analogs substitute.name = substitute.getarguments ().getString("name", substitute.name);
statement += "getArguments().";
} else {
throw new IllegalAccessException("The field [" + fieldName + "] need autowired from intent, its parent must be activity or fragment!");
}
statement = buildStatement(originalValue, statement, typeUtils.typeExchange(element), isActivity, isKtClass(parent));
if (statement.startsWith("serializationService.")) { // Not mortals
injectMethodBuilder.beginControlFlow("if (null ! = serializationService)");
injectMethodBuilder.addStatement(
"substitute." + fieldName + "=" + statement,
(StringUtils.isEmpty(fieldConfig.name()) ? fieldName : fieldConfig.name()),
ClassName.get(element.asType())
);
injectMethodBuilder.nextControlFlow("else");
injectMethodBuilder.addStatement(
"$T.e(\"" + Consts.TAG + "\", \"You want automatic inject the field '" + fieldName + "' in class '$T' , then you should implement 'SerializationService' to support object auto inject! \ ")", AndroidLog, ClassName.get(parent));
injectMethodBuilder.endControlFlow();
} else {
injectMethodBuilder.addStatement(statement, StringUtils.isEmpty(fieldConfig.name()) ? fieldName : fieldConfig.name());
}
// Validator
if(fieldConfig.required() && ! element.asType().getKind().isPrimitive()) {// Primitive wont be check.
injectMethodBuilder.beginControlFlow("if (null == substitute." + fieldName + ")");
injectMethodBuilder.addStatement(
"$T.e(\"" + Consts.TAG + "\", \"The field '" + fieldName + "' is null, in class '\" + $T.class.getName() + \"! \ ")", AndroidLog, ClassName.get(parent));
injectMethodBuilder.endControlFlow();
}
}
}
helper.addMethod(injectMethodBuilder.build());
// Generate autowire helper
JavaFile.builder(packageName, helper.build()).build().writeTo(mFiler);
logger.info("> > >" + parent.getSimpleName() + " has been processed, " + fileName + " has been generated. <<<");
}
logger.info(">>> Autowired processor stop. <<<"); }}Copy the codeThe resulting class looks something like this
