关于 springboot 启动流程和配置原理 很久就写了，不过没有详细补充 ,现在补充 —— 2023-08-05
启动原理
@SpringBootApplication
public class Start {
public static void main(String[] args) {
SpringApplication.run(Start.class, args);
}
}
SpringApplication
public SpringApplication(ResourceLoader resourceLoader, Class<?>... primarySources) {
this.sources = new LinkedHashSet(); //
this.bannerMode = Mode.CONSOLE;// 控制banner
this.logStartupInfo = true;// 是否启动日志
this.addCommandLineProperties = true; // 读取命令行配置
this.addConversionService = true; //添加转换器
this.headless = true; //
this.registerShutdownHook = true; // 注册重启
this.additionalProfiles = Collections.emptySet();// 读取配置环境
this.isCustomEnvironment = false;// 是否是自定义环境
this.lazyInitialization = false; // 是否懒加载
this.applicationContextFactory = ApplicationContextFactory.DEFAULT;
this.applicationStartup = ApplicationStartup.DEFAULT; // ApplicationStartup DEFAULT = new DefaultApplicationStartup();
this.resourceLoader = resourceLoader;// 资源加载器
Assert.notNull(primarySources, "PrimarySources must not be null");
this.primarySources = new LinkedHashSet(Arrays.asList(primarySources)); // 主程序
this.webApplicationType = WebApplicationType.deduceFromClasspath();// SERVLET||REACTIVE; 是servlet还是reactive环境
// BootstrapRegistryInitializer
this.bootstrapRegistryInitializers = new ArrayList(this.getSpringFactoriesInstances(BootstrapRegistryInitializer.class));
// ApplicationContextInitializer
this.setInitializers(this.getSpringFactoriesInstances(ApplicationContextInitializer.class));
// ApplicationListener
this.setListeners(this.getSpringFactoriesInstances(ApplicationListener.class));
this.mainApplicationClass = this.deduceMainApplicationClass();
}
BootstrapRegistryInitializer
BootstrapRegistryInitializer 是一个函数是接口
@FunctionalInterface
public interface BootstrapRegistryInitializer {
void initialize(BootstrapRegistry registry);
}
org.springframework.boot.BootstrapRegistry 接口
getSpringFactoriesInstances
private <T> Collection<T> getSpringFactoriesInstances(Class<T> type) {
return getSpringFactoriesInstances(type, new Class<?>[] {});
}
private <T> Collection<T> getSpringFactoriesInstances(Class<T> type, Class<?>[] parameterTypes, Object... args) {
ClassLoader classLoader = getClassLoader();
// 使用 set 结构去重
Set<String> names = new LinkedHashSet<>(SpringFactoriesLoader.loadFactoryNames(type, classLoader));
List<T> instances = createSpringFactoriesInstances(type, parameterTypes, classLoader, args, names);
// 加载完毕后排序
AnnotationAwareOrderComparator.sort(instances);
return instances;
}
加载工厂中组件实现方式
org.springframework.core.io.support.SpringFactoriesLoader#loadSpringFactories
// 1、加载配置
private static Map<String, List<String>> loadSpringFactories(ClassLoader classLoader) {
Map<String, List<String>> result = (Map)cache.get(classLoader);
if (result != null) {
return result;
} else {
HashMap result = new HashMap();
try {
//核心 从这里知道读取配置文件位置 默认
Enumeration urls = classLoader.getResources("META-INF/spring.factories");
// ... 这里省略迭代器遍历注册
// result.replaceAll 该函数的作用是对每个值进行去重，并将去重后的结果存储为一个不可修改的列表。最后，replaceAll 方法使用这个函数的结果来替换原始的键值对中的值
result.replaceAll((factoryType, implementations) -> {
return (List)implementations.stream().distinct().collect(Collectors.collectingAndThen(Collectors.toList(), Collections::unmodifiableList));
});
// 添加到缓存中 下次读取先获取类加载器 通过类加载器获取 map 结构再获取 bean
// cache 结构
// static final Map<ClassLoader, Map<String, List<String>>> cache = new ConcurrentReferenceHashMap<>();
cache.put(classLoader, result);
return result;
} catch (IOException var14) {
// 错误异常信息
}
}
}
加载的配置文件
spring-boot:2.7.1.META-INF\spring.factorie
org.springframework.context.ApplicationContextInitializer=\
org.springframework.boot.context.ConfigurationWarningsApplicationContextInitializer,\
org.springframework.boot.context.ContextIdApplicationContextInitializer,\
org.springframework.boot.context.config.DelegatingApplicationContextInitializer,\
org.springframework.boot.rsocket.context.RSocketPortInfoApplicationContextInitializer,\
org.springframework.boot.web.context.ServerPortInfoApplicationContextInitializer
像 BootstrapRegistryInitializer
另外几个配置是从其他配置文件中读取的
例如
createSpringFactoriesInstances
``org.springframework.core.io.support.SpringFactoriesLoader#createSpringFactoriesInstances 构建实例对象
// 2、获取构造器实例
private <T> List<T> createSpringFactoriesInstances(Class<T> type, Class<?>[] parameterTypes, ClassLoader classLoader, Object[] args, Set<String> names) {
List<T> instances = new ArrayList(names.size());
Iterator var7 = names.iterator();
while(var7.hasNext()) {
String name = (String)var7.next();
try {
// 通过类名反射机制调用，读取Class<T> class
Class<?> instanceClass = ClassUtils.forName(name, classLoader);
Assert.isAssignable(type, instanceClass);
Constructor<?> constructor = instanceClass.getDeclaredConstructor(parameterTypes);
// 通过 BeanUtils 提供静态方法 instantiateClass ()
// 通过构造函数 和参数 构造一个实例对象
// 最终调用的是
T instance = BeanUtils.instantiateClass(constructor, args);
// 添加到构造器中
instances.add(instance);
} catch (Throwable var12) {
// throw error
}
}
// 返回
return instances;
}
// 排序 通过debug这里调用的是Integer类型排序方法 List<Integer> list
public static void sort(List<?> list) {
if (list.size() > 1) {
list.sort(INSTANCE);
}
}
需要注意的是 BeanUtils.instantiateClass 最终调用的是java.lang.Class#form0 由 底层实现
private static native Class<?> forName0(String name, boolean initialize,
ClassLoader loader,
Class<?> caller)
throws ClassNotFoundException;
AnnotationAwareOrderComparator
加载实例完毕后是由 org.springframework.core.annotation.AnnotationAwareOrderComparator
public class AnnotationAwareOrderComparator extends OrderComparator {
public static final AnnotationAwareOrderComparator INSTANCE = new AnnotationAwareOrderComparator();
public static void sort(List<?> list) {
if (list.size() > 1) {
// 采用单例模式实现
// 比较器由 OrderComparator 实现
list.sort(INSTANCE);
}
}
}
比较器实现 org.springframework.core.OrderComparator#doCompare()
private int doCompare(@Nullable Object o1, @Nullable Object o2, @Nullable OrderSourceProvider sourceProvider) {
// PriorityOrdered 是一种优先级排序
boolean p1 = (o1 instanceof PriorityOrdered);
boolean p2 = (o2 instanceof PriorityOrdered);
// 逆序
if (p1 && !p2) {
return -1;
}
// 顺序
else if (p2 && !p1) {
return 1;
}
int i1 = getOrder(o1, sourceProvider);
int i2 = getOrder(o2, sourceProvider);
// 最终交给 Integer 的比较器排序
return Integer.compare(i1, i2);
}
ApplicationContextInitializer
同 BootstrapRegistryInitializer加载原理
ApplicationListener
同 BootstrapRegistryInitializer加载原理
总结
run
执行流程
public ConfigurableApplicationContext run(String... args) {
// 初次启动时间
long startTime = System.nanoTime();
// 默认上下文环境
DefaultBootstrapContext bootstrapContext = this.createBootstrapContext();
ConfigurableApplicationContext context = null;
this.configureHeadlessProperty();
SpringApplicationRunListeners listeners = this.getRunListeners(args);
listeners.starting(bootstrapContext, this.mainApplicationClass);
try {
ApplicationArguments applicationArguments = new DefaultApplicationArguments(args);
// 加载配置文件
ConfigurableEnvironment environment = this.prepareEnvironment(listeners, bootstrapContext, applicationArguments);
this.configureIgnoreBeanInfo(environment);
// 图形 Banner
Banner printedBanner = this.printBanner(environment);
context = this.createApplicationContext();
context.setApplicationStartup(this.applicationStartup);
this.prepareContext(bootstrapContext, context, environment, listeners, applicationArguments, printedBanner);
// 加载所有注解使用的扫描的组件
this.refreshContext(context);
// 刷新
this.afterRefresh(context, applicationArguments);
Duration timeTakenToStartup = Duration.ofNanos(System.nanoTime() - startTime);
if (this.logStartupInfo) {
(new StartupInfoLogger(this.mainApplicationClass)).logStarted(this.getApplicationLog(), timeTakenToStartup);
}
// 启动 listener
listeners.started(context, timeTakenToStartup);
// 加载完毕处理 调用函数是接口 ApplicationRunner run 方法
// ApplicationRunner
// CommandLineRunner
this.callRunners(context, applicationArguments);
} catch (Throwable var12) {
// 启动失败调用 ApplicationEventPublisher 接口实现
// 事件推送
this.handleRunFailure(context, var12, listeners);
throw new IllegalStateException(var12);
}
try {
Duration timeTakenToReady = Duration.ofNanos(System.nanoTime() - startTime);
// 加载完毕 事件通过 doWithListeners 触发
listeners.ready(context, timeTakenToReady);
return context;
} catch (Throwable var11) {
this.handleRunFailure(context, var11, (SpringApplicationRunListeners)null);
throw new IllegalStateException(var11);
}
}
createBootstrapContext
private DefaultBootstrapContext createBootstrapContext() {
DefaultBootstrapContext bootstrapContext = new DefaultBootstrapContext();
this.bootstrapRegistryInitializers.forEach((initializer) -> initializer.initialize(bootstrapContext));
return bootstrapContext;
}
configureHeadlessProperty
private void configureHeadlessProperty() {
System.setProperty(SYSTEM_PROPERTY_JAVA_AWT_HEADLESS,
System.getProperty(SYSTEM_PROPERTY_JAVA_AWT_HEADLESS, Boolean.toString(this.headless)));
}
getRunListeners
private SpringApplicationRunListeners getRunListeners(String[] args) {
Class<?>[] types = new Class<?>[] { SpringApplication.class, String[].class };
return new SpringApplicationRunListeners(logger,
// 获取 SpringApplicationRunListener 类型 侦听器， 在构造函数创建时候已经调用了
//
getSpringFactoriesInstances(SpringApplicationRunListener.class, types, this, args),
this.applicationStartup);
}
获取 侦听器，这次走缓存
listeners.starting
启动侦听器经过这里 org.springframework.boot.SpringApplicationRunListeners
void starting(ConfigurableBootstrapContext bootstrapContext, Class<?> mainApplicationClass) {
doWithListeners("spring.boot.application.starting", (listener) -> listener.starting(bootstrapContext),
(step) -> {
if (mainApplicationClass != null) {
step.tag("mainApplicationClass", mainApplicationClass.getName());
}
});
}
@Override
public void starting(ConfigurableBootstrapContext bootstrapContext) {
this.initialMulticaster
.multicastEvent(new ApplicationStartingEvent(bootstrapContext, this.application, this.args));
}
最终触发事件 org.springframework.context.event.SimpleApplicationEventMulticaster
private void doInvokeListener(ApplicationListener listener, ApplicationEvent event) {
try {
listener.onApplicationEvent(event);
}
catch (ClassCastException ex) {
// 异常处理
}
}
org.springframework.boot.context.logging.LoggingApplicationListener#onApplicationEvent
@Override
public void onApplicationEvent(ApplicationEvent event) {
if (event instanceof ApplicationStartingEvent) {
onApplicationStartingEvent((ApplicationStartingEvent) event);
}
else if (event instanceof ApplicationEnvironmentPreparedEvent) {
onApplicationEnvironmentPreparedEvent((ApplicationEnvironmentPreparedEvent) event);
}
else if (event instanceof ApplicationPreparedEvent) {
onApplicationPreparedEvent((ApplicationPreparedEvent) event);
}
else if (event instanceof ContextClosedEvent) {
onContextClosedEvent((ContextClosedEvent) event);
}
else if (event instanceof ApplicationFailedEvent) {
onApplicationFailedEvent();
}
}
DefaultApplicationArguments
默认参数类 org.springframework.boot.DefaultApplicationArguments
此构造函数作用是保存命令参数 如 java -jar -Dspring.xxxx.yyy=cccc mmm.jar 获取参数信息
public DefaultApplicationArguments(String... args) {
Assert.notNull(args, "Args must not be null");
this.source = new Source(args);
this.args = args;
}
prepareEnvironment
配置文件加载在这个逻辑中
private ConfigurableEnvironment prepareEnvironment(SpringApplicationRunListeners listeners,
DefaultBootstrapContext bootstrapContext, ApplicationArguments applicationArguments) {
// 获取配置环境 默认是 servlet
ConfigurableEnvironment environment = getOrCreateEnvironment();
// 环境参数处理
configureEnvironment(environment, applicationArguments.getSourceArgs());
ConfigurationPropertySources.attach(environment);
// 启动配置文件的侦听器
// 读取配置文件
listeners.environmentPrepared(bootstrapContext, environment);
// 默认配置文件合并
DefaultPropertiesPropertySource.moveToEnd(environment);
Assert.state(!environment.containsProperty("spring.main.environment-prefix"),
"Environment prefix cannot be set via properties.");
// 配置内容绑定到 SpringApplication 这个类中
bindToSpringApplication(environment);
// 非自定义环境
if (!this.isCustomEnvironment) {
environment = convertEnvironment(environment);
}
// 所有配置内容合并
ConfigurationPropertySources.attach(environment);
return environment;
}
获取 web 环境
private ConfigurableEnvironment getOrCreateEnvironment() {
if (this.environment != null) {
return this.environment;
}
// 如果不做默认配置 默认是 SERVLET
switch (this.webApplicationType) {
// 默认 servelt 环境
case SERVLET:
return new ApplicationServletEnvironment();
// 响应式编程
case REACTIVE:
return new ApplicationReactiveWebEnvironment();
default:
return new ApplicationEnvironment();
}
}
配置文件加载流程
void environmentPrepared(ConfigurableBootstrapContext bootstrapContext, ConfigurableEnvironment environment) {
doWithListeners("spring.boot.application.environment-prepared",
(listener) -> listener.environmentPrepared(bootstrapContext, environment));
}
org.springframework.boot.env.EnvironmentPostProcessorApplicationListener#onApplicationEnvironmentPreparedEvent()
private void onApplicationEnvironmentPreparedEvent(ApplicationEnvironmentPreparedEvent event) {
ConfigurableEnvironment environment = event.getEnvironment();
SpringApplication application = event.getSpringApplication();
for (EnvironmentPostProcessor postProcessor : getEnvironmentPostProcessors(application.getResourceLoader(),
event.getBootstrapContext())) {
postProcessor.postProcessEnvironment(environment, application);
}
}
org.springframework.core.env.#addFirst
public void addFirst(PropertySource<?> propertySource) {
synchronized (this.propertySourceList) {
removeIfPresent(propertySource);
// 添加第一个位置
this.propertySourceList.add(0, propertySource);
}
}
第一个配置类包括所有内容
configureIgnoreBeanInfo
private void configureIgnoreBeanInfo(ConfigurableEnvironment environment) {
if (System.getProperty(CachedIntrospectionResults.IGNORE_BEANINFO_PROPERTY_NAME) == null) {
Boolean ignore = environment.getProperty("spring.beaninfo.ignore", Boolean.class, Boolean.TRUE);
System.setProperty(CachedIntrospectionResults.IGNORE_BEANINFO_PROPERTY_NAME, ignore.toString());
}
}
printBanner
private Banner printBanner(ConfigurableEnvironment environment) {
// 如果 Banner.Mode.OFF 将不会打印Banner内容
// 默认为 CONOSLE 也就是输出
if (this.bannerMode == Banner.Mode.OFF) {
return null;
}
ResourceLoader resourceLoader = (this.resourceLoader != null) ? this.resourceLoader
: new DefaultResourceLoader(null);
SpringApplicationBannerPrinter bannerPrinter = new SpringApplicationBannerPrinter(resourceLoader, this.banner);
if (this.bannerMode == Mode.LOG) {
return bannerPrinter.print(environment, this.mainApplicationClass, logger);
}
return bannerPrinter.print(environment, this.mainApplicationClass, System.out);
}
org.springframework.boot.SpringApplicationBannerPrinter#print
阅读上面内容知道一下内容
- 指定位置信息
- 指定图片位置信息
- 默认为
banner.txt - 图片格式
Banner print(Environment environment, Class<?> sourceClass, PrintStream out) {
Banner banner = getBanner(environment);
banner.printBanner(environment, sourceClass, out);
return new PrintedBanner(banner, sourceClass);
}
org.springframework.boot.SpringBootBanner
默认Banner 内容
class SpringBootBanner implements Banner {
private static final String[] BANNER = { "", " . ____ _ __ _ _",
" /\\\\ / ___'_ __ _ _(_)_ __ __ _ \\ \\ \\ \\", "( ( )\\___ | '_ | '_| | '_ \\/ _` | \\ \\ \\ \\",
" \\\\/ ___)| |_)| | | | | || (_| | ) ) ) )", " ' |____| .__|_| |_|_| |_\\__, | / / / /",
" =========|_|==============|___/=/_/_/_/" };
private static final String SPRING_BOOT = " :: Spring Boot :: ";
private static final int STRAP_LINE_SIZE = 42;
@Override
public void printBanner(Environment environment, Class<?> sourceClass, PrintStream printStream) {
for (String line : BANNER) {
// 输出 BANNER
printStream.println(line);
}
// 获取版本号信息
String version = SpringBootVersion.getVersion();
version = (version != null) ? " (v" + version + ")" : "";
StringBuilder padding = new StringBuilder();
while (padding.length() < STRAP_LINE_SIZE - (version.length() + SPRING_BOOT.length())) {
padding.append(" ");
}
// 最终经过 打印流输出 上面内容
printStream.println(AnsiOutput.toString(AnsiColor.GREEN, SPRING_BOOT, AnsiColor.DEFAULT, padding.toString(),
AnsiStyle.FAINT, version));
printStream.println();
}
}
createApplicationContext
org.springframework.boot.ApplicationContextFactory
获取服务器环境 默认是 servlet环境
ApplicationContextFactory DEFAULT = (webApplicationType) -> {
try {
for (ApplicationContextFactory candidate : SpringFactoriesLoader
.loadFactories(ApplicationContextFactory.class, ApplicationContextFactory.class.getClassLoader())) {
ConfigurableApplicationContext context = candidate.create(webApplicationType);
if (context != null) {
return context;
}
}
return new AnnotationConfigApplicationContext();
}
catch (Exception ex) {
// hanlder error
}
};
重写接口两个类
setApplicationStartup
设置
prepareContext
private void prepareContext(ConfigurableApplicationContext context, ConfigurableEnvironment environment,
SpringApplicationRunListeners listeners, ApplicationArguments applicationArguments, Banner printedBanner) {
// 上下文中设置环境
context.setEnvironment(environment);
// 上下文处理
postProcessApplicationContext(context);
// 初始化
applyInitializers(context);
// 监听器中放入上下文
listeners.contextPrepared(context);
if (this.logStartupInfo) {
logStartupInfo(context.getParent() == null);
logStartupProfileInfo(context);
}
// Add boot specific singleton beans
ConfigurableListableBeanFactory beanFactory = context.getBeanFactory();
// 单例对象注册
beanFactory.registerSingleton("springApplicationArguments", applicationArguments);
if (printedBanner != null) {
beanFactory.registerSingleton("springBootBanner", printedBanner);
}
if (beanFactory instanceof DefaultListableBeanFactory) {
((DefaultListableBeanFactory) beanFactory)
.setAllowBeanDefinitionOverriding(this.allowBeanDefinitionOverriding);
}
if (this.lazyInitialization) {
context.addBeanFactoryPostProcessor(new LazyInitializationBeanFactoryPostProcessor());
}
// Load the sources
Set<Object> sources = getAllSources();
Assert.notEmpty(sources, "Sources must not be empty");
// 加载上下文
load(context, sources.toArray(new Object[0]));
// 监听器做加载上下文操作
listeners.contextLoaded(context);
}
注册类型转换器
refreshContext
核心实现 org.springframework.context.support.AbstractApplicationContext.refresh()
@Override
public void refresh() throws BeansException, IllegalStateException {
synchronized (this.startupShutdownMonitor) {
StartupStep contextRefresh = this.applicationStartup.start("spring.context.refresh");
// Prepare this context for refreshing.
prepareRefresh();
// Tell the subclass to refresh the internal bean factory.
ConfigurableListableBeanFactory beanFactory = obtainFreshBeanFactory();
// Prepare the bean factory for use in this context.
prepareBeanFactory(beanFactory);
try {
// Allows post-processing of the bean factory in context subclasses.
postProcessBeanFactory(beanFactory);
StartupStep beanPostProcess = this.applicationStartup.start("spring.context.beans.post-process");
// Invoke factory processors registered as beans in the context.
invokeBeanFactoryPostProcessors(beanFactory);
// Register bean processors that intercept bean creation.
registerBeanPostProcessors(beanFactory);
beanPostProcess.end();
// Initialize message source for this context.
initMessageSource();
// Initialize event multicaster for this context.
initApplicationEventMulticaster();
// Initialize other special beans in specific context subclasses.
onRefresh();
// Check for listener beans and register them.
registerListeners();
// Instantiate all remaining (non-lazy-init) singletons.
finishBeanFactoryInitialization(beanFactory);
// Last step: publish corresponding event.
finishRefresh();
}
catch (BeansException ex) {
if (logger.isWarnEnabled()) {
logger.warn("Exception encountered during context initialization - " +
"cancelling refresh attempt: " + ex);
}
// Destroy already created singletons to avoid dangling resources.
destroyBeans();
// Reset 'active' flag.
cancelRefresh(ex);
// Propagate exception to caller.
throw ex;
}
finally {
// Reset common introspection caches in Spring's core, since we
// might not ever need metadata for singleton beans anymore...
resetCommonCaches();
contextRefresh.end();
}
}
}
afterRefresh
这个方法什么都没写 为以后拓展需要
protected void afterRefresh(ConfigurableApplicationContext context, ApplicationArguments args) {
}
started
任务开始启动中...
void started(ConfigurableApplicationContext context, Duration timeTaken) {
doWithListeners("spring.boot.application.started", (listener) -> listener.started(context, timeTaken));
}
由 org.springframework.boot.context.event.EventPublishingRunListener#started()实现
@Override
public void started(ConfigurableApplicationContext context, Duration timeTaken) {
// 发布事件
context.publishEvent(new ApplicationStartedEvent(this.application, this.args, context, timeTaken));
// 发布事件
AvailabilityChangeEvent.publish(context, LivenessState.CORRECT);
}
实现类
callRunners
private void callRunners(ApplicationContext context, ApplicationArguments args) {
List<Object> runners = new ArrayList<>();
// 从容器工厂中获取 ApplicationRunner 和 CommandLineRunner 的子类对象
runners.addAll(context.getBeansOfType(ApplicationRunner.class).values());
runners.addAll(context.getBeansOfType(CommandLineRunner.class).values());
// 排序下
AnnotationAwareOrderComparator.sort(runners);
// 执行 run
for (Object runner : new LinkedHashSet<>(runners)) {
if (runner instanceof ApplicationRunner) {
callRunner((ApplicationRunner) runner, args);
}
if (runner instanceof CommandLineRunner) {
callRunner((CommandLineRunner) runner, args);
}
}
}
// // org.springframework.boot.CommandLineRunner
@FunctionalInterface
public interface ApplicationRunner {
void run(ApplicationArguments args) throws Exception;
}
// org.springframework.boot.CommandLineRunner
@FunctionalInterface
public interface CommandLineRunner {
void run(String... args) throws Exception;
}
org.springframework.boot.SpringApplication.callRunner
private void callRunner(ApplicationRunner runner, ApplicationArguments args) {
try {
// 调用接口
(runner).run(args);
}
catch (Exception ex) {
throw new IllegalStateException("Failed to execute ApplicationRunner", ex);
}
}
private void callRunner(CommandLineRunner runner, ApplicationArguments args) {
try {
// 调用接口
(runner).run(args.getSourceArgs());
}
catch (Exception ex) {
throw new IllegalStateException("Failed to execute CommandLineRunner", ex);
}
}
handleRunFailure
private void handleRunFailure(ConfigurableApplicationContext context, Throwable exception,
SpringApplicationRunListeners listeners) {
try {
try {
handleExitCode(context, exception);
if (listeners != null) {
listeners.failed(context, exception);
}
}
finally {
reportFailure(getExceptionReporters(context), exception);
if (context != null) {
context.close();
shutdownHook.deregisterFailedApplicationContext(context);
}
}
}
catch (Exception ex) {
logger.warn("Unable to close ApplicationContext", ex);
}
ReflectionUtils.rethrowRuntimeException(exception);
}
private void handleExitCode(ConfigurableApplicationContext context, Throwable exception) {
// 获取错误 code
int exitCode = getExitCodeFromException(context, exception);
// 为什么是 不等于 0 ？
// 因为系统认为 System.exit(0) 是强制退出
if (exitCode != 0) {
if (context != null) {
// 发布错误 event
context.publishEvent(new ExitCodeEvent(context, exitCode));
}
SpringBootExceptionHandler handler = getSpringBootExceptionHandler();
if (handler != null) {
// 注册错误 code
handler.registerExitCode(exitCode);
}
}
}
ready
执行到这里基本上就完毕了，ready 意为就绪
void ready(ConfigurableApplicationContext context, Duration timeTaken) {
doWithListeners("spring.boot.application.ready", (listener) -> listener.ready(context, timeTaken));
}
doWithListeners
private void doWithListeners(String stepName, Consumer<SpringApplicationRunListener> listenerAction,
Consumer<StartupStep> stepAction) {
StartupStep step = this.applicationStartup.start(stepName);
// 触发 监听器 事件
this.listeners.forEach(listenerAction);
if (stepAction != null) {
// 触发事件
stepAction.accept(step);
}
// 结束
step.end();
}
所有组件经过org.springframework.context.annotation.ConfigurationClassBeanDefinitionReader方法加载注册组件
org.springframework.beans.factory.support.DefaultListableBeanFactory
registerBeanDefinition(definitionHolder.getBeanName(), definitionHolder.getBeanDefinition())
自动配置原理
思考问题
了解自动配置之前你可以思考以下问题
- 组件是如何注册的呢？如果让你来实现你扫描组件你会如何实现？需要注意哪些需求？
- 批量注册
使用中只需要在主类中使用 @SpringBootApplication 注解就可以扫描该类包下 所有注册的组件，注册组件
SpringBootApplication
// ... 常见省略
@SpringBootConfiguration
@EnableAutoConfiguration
@ComponentScan(
excludeFilters = {@Filter(
type = FilterType.CUSTOM,
classes = {TypeExcludeFilter.class}
), @Filter(
type = FilterType.CUSTOM,
classes = {AutoConfigurationExcludeFilter.class}
)}
)
public @interface SpringBootApplication {
@AliasFor(annotation = EnableAutoConfiguration.class)
Class<?>[] exclude() default {};
@AliasFor(annotation = EnableAutoConfiguration.class)
String[] excludeName() default {};
@AliasFor(annotation = ComponentScan.class,attribute = "basePackages")
String[] scanBasePackages() default {};
@AliasFor(annotation = ComponentScan.class,attribute = "basePackageClasses")
Class<?>[] scanBasePackageClasses() default {};
@AliasFor(annotation = ComponentScan.class,attribute = "nameGenerator")
Class<? extends BeanNameGenerator> nameGenerator() default BeanNameGenerator.class;
@AliasFor(annotation = Configuration.class)
boolean proxyBeanMethods() default true;
}
核心注解是
-
@SpringBootConfiguration- 本质是一个配置类
-
@EnableAutoConfiguration- 自动配置核心
EnableAutoConfiguration
@Target({ElementType.TYPE})
@Retention(RetentionPolicy.RUNTIME)
@Documented
@Inherited
@AutoConfigurationPackage
@Import({AutoConfigurationImportSelector.class})
public @interface EnableAutoConfiguration {
String ENABLED_OVERRIDE_PROPERTY = "spring.boot.enableautoconfiguration";
Class<?>[] exclude() default {};
String[] excludeName() default {};
}
核心是@Import({AutoConfigurationImportSelector.class}) ，将 AutoConfigurationImportSelector 注入实现了自动配置，也就是说 AutoConfigurationImportSelector 类具有自动注入组件功能，下面看看
AutoConfigurationImportSelector 类的实现吧
AutoConfigurationImportSelector
processConfigBeanDefinitions
解析配置文件类
org.springframework.context.annotation.ConfigurationClassPostProcessor#postProcessBeanDefinitionRegistry()
核心实现部分
public void processConfigBeanDefinitions(BeanDefinitionRegistry registry) {
List<BeanDefinitionHolder> configCandidates = new ArrayList<>();
// 获取所有已注册的 bean 的 name
String[] candidateNames = registry.getBeanDefinitionNames();
for (String beanName : candidateNames) {
// 通过 name 从 工厂中获取 bean
BeanDefinition beanDef = registry.getBeanDefinition(beanName);
// public static final String CONFIGURATION_CLASS_ATTRIBUTE =
//Conventions.getQualifiedAttributeName(ConfigurationClassPostProcessor.class, "configurationClass");
if (beanDef.getAttribute(ConfigurationClassUtils.CONFIGURATION_CLASS_ATTRIBUTE) != null) {
// ...
}
// 是不是配置类
else if (ConfigurationClassUtils.checkConfigurationClassCandidate(beanDef, this.metadataReaderFactory)) {
configCandidates.add(new BeanDefinitionHolder(beanDef, beanName));
}
}
// Return immediately if no @Configuration classes were found
if (configCandidates.isEmpty()) {
return;
}
// 根据条件排序
configCandidates.sort((bd1, bd2) -> {
int i1 = ConfigurationClassUtils.getOrder(bd1.getBeanDefinition());
int i2 = ConfigurationClassUtils.getOrder(bd2.getBeanDefinition());
return Integer.compare(i1, i2);
});
// Detect any custom bean name generation strategy supplied through the enclosing application context
SingletonBeanRegistry sbr = null;
if (registry instanceof SingletonBeanRegistry) {
sbr = (SingletonBeanRegistry) registry;
if (!this.localBeanNameGeneratorSet) {
BeanNameGenerator generator = (BeanNameGenerator) sbr.getSingleton(
AnnotationConfigUtils.CONFIGURATION_BEAN_NAME_GENERATOR);
if (generator != null) {
this.componentScanBeanNameGenerator = generator;
this.importBeanNameGenerator = generator;
}
}
}
// 运行环境判断
// 没有赋值一个默认环境
if (this.environment == null) {
this.environment = new StandardEnvironment();
}
// 解析所有配置类
ConfigurationClassParser parser = new ConfigurationClassParser(
this.metadataReaderFactory, this.problemReporter, this.environment,
this.resourceLoader, this.componentScanBeanNameGenerator, registry);
// 去重
Set<BeanDefinitionHolder> candidates = new LinkedHashSet<>(configCandidates);
Set<ConfigurationClass> alreadyParsed = new HashSet<>(configCandidates.size());
// 开始遍历所有配置类
do {
StartupStep processConfig = this.applicationStartup.start("spring.context.config-classes.parse");
// 核心逻辑
parser.parse(candidates);
// 校验
parser.validate();
// 获取所有配置类
Set<ConfigurationClass> configClasses = new LinkedHashSet<>(parser.getConfigurationClasses());
// 释放缓存
configClasses.removeAll(alreadyParsed);
// Read the model and create bean definitions based on its content
if (this.reader == null) {
this.reader = new ConfigurationClassBeanDefinitionReader(
registry, this.sourceExtractor, this.resourceLoader, this.environment,
this.importBeanNameGenerator, parser.getImportRegistry());
}
// reader 读取
// org.springframework.context.annotation.ConfigurationClassBeanDefinitionReader
this.reader.loadBeanDefinitions(configClasses);
alreadyParsed.addAll(configClasses);
processConfig.tag("classCount", () -> String.valueOf(configClasses.size())).end();
candidates.clear();
if (registry.getBeanDefinitionCount() > candidateNames.length) {
String[] newCandidateNames = registry.getBeanDefinitionNames();
Set<String> oldCandidateNames = new HashSet<>(Arrays.asList(candidateNames));
Set<String> alreadyParsedClasses = new HashSet<>();
for (ConfigurationClass configurationClass : alreadyParsed) {
alreadyParsedClasses.add(configurationClass.getMetadata().getClassName());
}
for (String candidateName : newCandidateNames) {
if (!oldCandidateNames.contains(candidateName)) {
BeanDefinition bd = registry.getBeanDefinition(candidateName);
if (ConfigurationClassUtils.checkConfigurationClassCandidate(bd, this.metadataReaderFactory) &&
!alreadyParsedClasses.contains(bd.getBeanClassName())) {
candidates.add(new BeanDefinitionHolder(bd, candidateName));
}
}
}
candidateNames = newCandidateNames;
}
}
// ...
}
parse
org.springframework.context.annotation.ConfigurationClassParser$DeferredImportSelectorGrouping#getImports
public Iterable<Group.Entry> getImports() {
for (DeferredImportSelectorHolder deferredImport : this.deferredImports) {
// 开始执行解析
this.group.process(deferredImport.getConfigurationClass().getMetadata(),
deferredImport.getImportSelector());
}
return this.group.selectImports();
}
可以看到类型是org.springframework.boot.autoconfigure.AutoConfigurationImportSelector$AutoConfigurationGroup
org.springframework.boot.autoconfigure.AutoConfigurationImportSelector$AutoConfigurationGroup#parse()
@Override
public void process(AnnotationMetadata annotationMetadata, DeferredImportSelector deferredImportSelector) {
// ...
AutoConfigurationEntry autoConfigurationEntry = ((AutoConfigurationImportSelector) deferredImportSelector)
// 读取配置信息
.getAutoConfigurationEntry(annotationMetadata);
this.autoConfigurationEntries.add(autoConfigurationEntry);
for (String importClassName : autoConfigurationEntry.getConfigurations()) {
this.entries.putIfAbsent(importClassName, annotationMetadata);
}
}
org.springframework.boot.autoconfigure.AutoConfigurationImportSelector#getAutoConfigurationEntry
判断是否开启了自动配置类注解
protected boolean isEnabled(AnnotationMetadata metadata) {
if (getClass() == AutoConfigurationImportSelector.class) {
return getEnvironment().getProperty(EnableAutoConfiguration.ENABLED_OVERRIDE_PROPERTY, Boolean.class, true);
}
return true;
}
读取的自动配置类
protected AutoConfigurationEntry getAutoConfigurationEntry(AnnotationMetadata annotationMetadata) {
if (!isEnabled(annotationMetadata)) {
return EMPTY_ENTRY;
}
AnnotationAttributes attributes = getAttributes(annotationMetadata);
// 加载 工厂中所有自动配置类
List<String> configurations = getCandidateConfigurations(annotationMetadata, attributes);
// 去重
configurations = removeDuplicates(configurations);
// 获取排除的类型
Set<String> exclusions = getExclusions(annotationMetadata, attributes);
// 排除 需要排除的类型
checkExcludedClasses(configurations, exclusions);
// 清空 释放内存
configurations.removeAll(exclusions);
// 获取过滤信息
configurations = getConfigurationClassFilter().filter(configurations);
fireAutoConfigurationImportEvents(configurations, exclusions);
return new AutoConfigurationEntry(configurations, exclusions);
}
经过筛选之后可以看到
``org.springframework.boot.autoconfigure.AutoConfigurationImportSelector#getCandidateConfigurations`
`
protected List<String> getCandidateConfigurations(AnnotationMetadata metadata, AnnotationAttributes attributes) {
// 获取 EnableAutoConfiguration.class bean
// 这就是为什么自动配置必须要使用 @EnableAutoConfiguration 这个注解了
List<String> configurations = SpringFactoriesLoader.loadFactoryNames(getSpringFactoriesLoaderFactoryClass(),
getBeanClassLoader());
// 断言部分 ...
return configurations;
}
org.springframework.boot.autoconfigure.AutoConfigurationImportSelector#getCandidateConfigurations
// 这就是为什么自动配置必须要使用 @EnableAutoConfiguration 这个注解了
protected Class<?> getSpringFactoriesLoaderFactoryClass() {
return EnableAutoConfiguration.class;
}
org.springframework.boot.autoconfigure.AutoConfigurationImportSelector#fireAutoConfigurationImportEvents
private void fireAutoConfigurationImportEvents(List<String> configurations, Set<String> exclusions) {
// 获取自动配置类的监听器
List<AutoConfigurationImportListener> listeners = getAutoConfigurationImportListeners();
if (!listeners.isEmpty()) {
// 获取 event
AutoConfigurationImportEvent event = new AutoConfigurationImportEvent(this, configurations, exclusions);
for (AutoConfigurationImportListener listener : listeners) {
invokeAwareMethods(listener);
listener.onAutoConfigurationImportEvent(event);
}
}
}
org.springframework.boot.autoconfigure.AutoConfigurationImportSelector#invokeAwareMethods
调用不同类型 event
private void invokeAwareMethods(Object instance) {
if (instance instanceof Aware) {
if (instance instanceof BeanClassLoaderAware) {
((BeanClassLoaderAware) instance).setBeanClassLoader(this.beanClassLoader);
}
if (instance instanceof BeanFactoryAware) {
((BeanFactoryAware) instance).setBeanFactory(this.beanFactory);
}
if (instance instanceof EnvironmentAware) {
((EnvironmentAware) instance).setEnvironment(this.environment);
}
if (instance instanceof ResourceLoaderAware) {
((ResourceLoaderAware) instance).setResourceLoader(this.resourceLoader);
}
}
}
selectImports
@Override
public Iterable<Entry> selectImports() {
// 非空
if (this.autoConfigurationEntries.isEmpty()) {
return Collections.emptyList();
}
// 一下所有都是根据条件注解过滤
Set<String> allExclusions = this.autoConfigurationEntries.stream()
.map(AutoConfigurationEntry::getExclusions).flatMap(Collection::stream).collect(Collectors.toSet());
//
Set<String> processedConfigurations = this.autoConfigurationEntries.stream()
.map(AutoConfigurationEntry::getConfigurations).flatMap(Collection::stream)
.collect(Collectors.toCollection(LinkedHashSet::new));
processedConfigurations.removeAll(allExclusions);
// 排序
return sortAutoConfigurations(processedConfigurations, getAutoConfigurationMetadata()).stream()
.map((importClassName) -> new Entry(this.entries.get(importClassName), importClassName))
.collect(Collectors.toList());
}
validate
校验核心逻辑
void validate(ProblemReporter problemReporter) {
// A configuration class may not be final (CGLIB limitation) unless it declares proxyBeanMethods=false
Map<String, Object> attributes = this.metadata.getAnnotationAttributes(Configuration.class.getName());
// 获取 proxyBeanMethods 属性
if (attributes != null && (Boolean) attributes.get("proxyBeanMethods")) {
// proxyBeanMethods 为 true 才执行下面逻辑
if (this.metadata.isFinal()) {
problemReporter.error(new FinalConfigurationProblem());
}
for (BeanMethod beanMethod : this.beanMethods) {
// 校验 有 BeanMethod类实现
beanMethod.validate(problemReporter);
}
}
}
org.springframework.context.annotation.BeanMethod#validate
@Override
public void validate(ProblemReporter problemReporter) {
// 对于静态的方法直接返回
if (getMetadata().isStatic()) {
return;
}
// 包含有配置类注解 Configuration.class
if (this.configurationClass.getMetadata().isAnnotated(Configuration.class.getName()))
{
// 重写
if (!getMetadata().isOverridable()) {
problemReporter.error(new NonOverridableMethodError());
}
}
}
readaer
public void loadBeanDefinitions(Set<ConfigurationClass> configurationModel) {
TrackedConditionEvaluator trackedConditionEvaluator = new TrackedConditionEvaluator();
for (ConfigurationClass configClass : configurationModel) {
loadBeanDefinitionsForConfigurationClass(configClass, trackedConditionEvaluator);
}
}
org.springframework.context.annotation.ConfigurationClassBeanDefinitionReader
这个类负责处理 配置的各种属性
- 别名
- ref
- autowire
核心方法是``org.springframework.context.annotation.ConfigurationClassBeanDefinitionReaderloadBeanDefinitionsForBeanMethod`
随便贴点吧文章来源：https://www.toymoban.com/news/detail-424489.html
private void loadBeanDefinitionsForBeanMethod(BeanMethod beanMethod) {
ConfigurationClass configClass = beanMethod.getConfigurationClass();
MethodMetadata metadata = beanMethod.getMetadata();
String methodName = metadata.getMethodName();
// Do we need to mark the bean as skipped by its condition?
if (this.conditionEvaluator.shouldSkip(metadata, ConfigurationPhase.REGISTER_BEAN)) {
configClass.skippedBeanMethods.add(methodName);
return;
}
if (configClass.skippedBeanMethods.contains(methodName)) {
return;
}
AnnotationAttributes bean = AnnotationConfigUtils.attributesFor(metadata, Bean.class);
Assert.state(bean != null, "No @Bean annotation attributes");
// Consider name and any aliases
List<String> names = new ArrayList<>(Arrays.asList(bean.getStringArray("name")));
String beanName = (!names.isEmpty() ? names.remove(0) : methodName);
// 别名组件
for (String alias : names) {
this.registry.registerAlias(beanName, alias);
}
// Has this effectively been overridden before (e.g. via XML)?
if (isOverriddenByExistingDefinition(beanMethod, beanName)) {
if (beanName.equals(beanMethod.getConfigurationClass().getBeanName())) {
// ...
}
return;
}
ConfigurationClassBeanDefinition beanDef = new ConfigurationClassBeanDefinition(configClass, metadata, beanName);
beanDef.setSource(this.sourceExtractor.extractSource(metadata, configClass.getResource()));
if (metadata.isStatic()) {
// static @Bean method
if (configClass.getMetadata() instanceof StandardAnnotationMetadata) {
beanDef.setBeanClass(((StandardAnnotationMetadata) configClass.getMetadata()).getIntrospectedClass());
}
else {
beanDef.setBeanClassName(configClass.getMetadata().getClassName());
}
beanDef.setUniqueFactoryMethodName(methodName);
}
else {
// instance @Bean method
beanDef.setFactoryBeanName(configClass.getBeanName());
beanDef.setUniqueFactoryMethodName(methodName);
}
if (metadata instanceof StandardMethodMetadata) {
beanDef.setResolvedFactoryMethod(((StandardMethodMetadata) metadata).getIntrospectedMethod());
}
beanDef.setAutowireMode(AbstractBeanDefinition.AUTOWIRE_CONSTRUCTOR);
beanDef.setAttribute(org.springframework.beans.factory.annotation.RequiredAnnotationBeanPostProcessor.
SKIP_REQUIRED_CHECK_ATTRIBUTE, Boolean.TRUE);
AnnotationConfigUtils.processCommonDefinitionAnnotations(beanDef, metadata);
Autowire autowire = bean.getEnum("autowire");
if (autowire.isAutowire()) {
beanDef.setAutowireMode(autowire.value());
}
boolean autowireCandidate = bean.getBoolean("autowireCandidate");
if (!autowireCandidate) {
beanDef.setAutowireCandidate(false);
}
String initMethodName = bean.getString("initMethod");
if (StringUtils.hasText(initMethodName)) {
beanDef.setInitMethodName(initMethodName);
}
String destroyMethodName = bean.getString("destroyMethod");
beanDef.setDestroyMethodName(destroyMethodName);
// Consider scoping
ScopedProxyMode proxyMode = ScopedProxyMode.NO;
AnnotationAttributes attributes = AnnotationConfigUtils.attributesFor(metadata, Scope.class);
if (attributes != null) {
beanDef.setScope(attributes.getString("value"));
proxyMode = attributes.getEnum("proxyMode");
if (proxyMode == ScopedProxyMode.DEFAULT) {
proxyMode = ScopedProxyMode.NO;
}
}
// ref
BeanDefinition beanDefToRegister = beanDef;
if (proxyMode != ScopedProxyMode.NO) {
BeanDefinitionHolder proxyDef = ScopedProxyCreator.createScopedProxy(
new BeanDefinitionHolder(beanDef, beanName), this.registry,
proxyMode == ScopedProxyMode.TARGET_CLASS);
beanDefToRegister = new ConfigurationClassBeanDefinition(
(RootBeanDefinition) proxyDef.getBeanDefinition(), configClass, metadata, beanName);
}
this.registry.registerBeanDefinition(beanName, beanDefToRegister);
}
AutoConfigurationImportSelector 补充
标志位信息
标志位数字，JMV加载后的标志位 由 org.springframework.asm.Opcodes，由于存放在接口中的常量，天然是静态方法文章来源地址https://www.toymoban.com/news/detail-424489.html
public interface Opcodes {
// ASM API versions.
int ASM4 = 4 << 16 | 0 << 8;
int ASM5 = 5 << 16 | 0 << 8;
int ASM6 = 6 << 16 | 0 << 8;
int ASM7 = 7 << 16 | 0 << 8;
int ASM8 = 8 << 16 | 0 << 8;
int ASM9 = 9 << 16 | 0 << 8;
int SOURCE_DEPRECATED = 0x100;
int SOURCE_MASK = SOURCE_DEPRECATED;
int V1_1 = 3 << 16 | 45;
int V1_2 = 0 << 16 | 46;
int V1_3 = 0 << 16 | 47;
int V1_4 = 0 << 16 | 48;
int V1_5 = 0 << 16 | 49;
int V1_6 = 0 << 16 | 50;
int V1_7 = 0 << 16 | 51;
int V1_8 = 0 << 16 | 52;
int V9 = 0 << 16 | 53;
int V10 = 0 << 16 | 54;
int V11 = 0 << 16 | 55;
int V12 = 0 << 16 | 56;
int V13 = 0 << 16 | 57;
int V14 = 0 << 16 | 58;
int V15 = 0 << 16 | 59;
int V16 = 0 << 16 | 60;
int V17 = 0 << 16 | 61;
int V18 = 0 << 16 | 62;
int V19 = 0 << 16 | 63;
/**
* Version flag indicating that the class is using 'preview' features.
*
* <p>{@code version & V_PREVIEW == V_PREVIEW} tests if a version is flagged with {@code
* V_PREVIEW}.
*/
int V_PREVIEW = 0xFFFF0000;
// Access flags values, defined in
// - https://docs.oracle.com/javase/specs/jvms/se9/html/jvms-4.html#jvms-4.1-200-E.1
// - https://docs.oracle.com/javase/specs/jvms/se9/html/jvms-4.html#jvms-4.5-200-A.1
// - https://docs.oracle.com/javase/specs/jvms/se9/html/jvms-4.html#jvms-4.6-200-A.1
// - https://docs.oracle.com/javase/specs/jvms/se9/html/jvms-4.html#jvms-4.7.25
int ACC_PUBLIC = 0x0001; // class, field, method
int ACC_PRIVATE = 0x0002; // class, field, method
int ACC_PROTECTED = 0x0004; // class, field, method
int ACC_STATIC = 0x0008; // field, method
int ACC_FINAL = 0x0010; // class, field, method, parameter
int ACC_SUPER = 0x0020; // class
int ACC_SYNCHRONIZED = 0x0020; // method
int ACC_OPEN = 0x0020; // module
int ACC_TRANSITIVE = 0x0020; // module requires
int ACC_VOLATILE = 0x0040; // field
int ACC_BRIDGE = 0x0040; // method
int ACC_STATIC_PHASE = 0x0040; // module requires
int ACC_VARARGS = 0x0080; // method
int ACC_TRANSIENT = 0x0080; // field
int ACC_NATIVE = 0x0100; // method
int ACC_INTERFACE = 0x0200; // class
int ACC_ABSTRACT = 0x0400; // class, method
int ACC_STRICT = 0x0800; // method
int ACC_SYNTHETIC = 0x1000; // class, field, method, parameter, module *
int ACC_ANNOTATION = 0x2000; // class
int ACC_ENUM = 0x4000; // class(?) field inner
int ACC_MANDATED = 0x8000; // field, method, parameter, module, module *
int ACC_MODULE = 0x8000; // class
// ASM specific access flags.
// WARNING: the 16 least significant bits must NOT be used, to avoid conflicts with standard
// access flags, and also to make sure that these flags are automatically filtered out when
// written in class files (because access flags are stored using 16 bits only).
int ACC_RECORD = 0x10000; // class
int ACC_DEPRECATED = 0x20000; // class, field, method
// Possible values for the type operand of the NEWARRAY instruction.
// See https://docs.oracle.com/javase/specs/jvms/se9/html/jvms-6.html#jvms-6.5.newarray.
int T_BOOLEAN = 4;
int T_CHAR = 5;
int T_FLOAT = 6;
int T_DOUBLE = 7;
int T_BYTE = 8;
int T_SHORT = 9;
int T_INT = 10;
int T_LONG = 11;
// Possible values for the reference_kind field of CONSTANT_MethodHandle_info structures.
// See https://docs.oracle.com/javase/specs/jvms/se9/html/jvms-4.html#jvms-4.4.8.
int H_GETFIELD = 1;
int H_GETSTATIC = 2;
int H_PUTFIELD = 3;
int H_PUTSTATIC = 4;
int H_INVOKEVIRTUAL = 5;
int H_INVOKESTATIC = 6;
int H_INVOKESPECIAL = 7;
int H_NEWINVOKESPECIAL = 8;
int H_INVOKEINTERFACE = 9;
// ASM specific stack map frame types, used in {@link ClassVisitor#visitFrame}.
/** An expanded frame. See {@link ClassReader#EXPAND_FRAMES}. */
int F_NEW = -1;
/** A compressed frame with complete frame data. */
int F_FULL = 0;
/**
* A compressed frame where locals are the same as the locals in the previous frame, except that
* additional 1-3 locals are defined, and with an empty stack.
*/
int F_APPEND = 1;
/**
* A compressed frame where locals are the same as the locals in the previous frame, except that
* the last 1-3 locals are absent and with an empty stack.
*/
int F_CHOP = 2;
/**
* A compressed frame with exactly the same locals as the previous frame and with an empty stack.
*/
int F_SAME = 3;
/**
* A compressed frame with exactly the same locals as the previous frame and with a single value
* on the stack.
*/
int F_SAME1 = 4;
// Standard stack map frame element types, used in {@link ClassVisitor#visitFrame}.
Integer TOP = Frame.ITEM_TOP;
Integer INTEGER = Frame.ITEM_INTEGER;
Integer FLOAT = Frame.ITEM_FLOAT;
Integer DOUBLE = Frame.ITEM_DOUBLE;
Integer LONG = Frame.ITEM_LONG;
Integer NULL = Frame.ITEM_NULL;
Integer UNINITIALIZED_THIS = Frame.ITEM_UNINITIALIZED_THIS;
// The JVM opcode values (with the MethodVisitor method name used to visit them in comment, and
// where '-' means 'same method name as on the previous line').
// See https://docs.oracle.com/javase/specs/jvms/se9/html/jvms-6.html.
int NOP = 0; // visitInsn
int ACONST_NULL = 1; // -
int ICONST_M1 = 2; // -
int ICONST_0 = 3; // -
int ICONST_1 = 4; // -
int ICONST_2 = 5; // -
int ICONST_3 = 6; // -
int ICONST_4 = 7; // -
int ICONST_5 = 8; // -
int LCONST_0 = 9; // -
int LCONST_1 = 10; // -
int FCONST_0 = 11; // -
int FCONST_1 = 12; // -
int FCONST_2 = 13; // -
int DCONST_0 = 14; // -
int DCONST_1 = 15; // -
int BIPUSH = 16; // visitIntInsn
int SIPUSH = 17; // -
int LDC = 18; // visitLdcInsn
int ILOAD = 21; // visitVarInsn
int LLOAD = 22; // -
int FLOAD = 23; // -
int DLOAD = 24; // -
int ALOAD = 25; // -
int IALOAD = 46; // visitInsn
int LALOAD = 47; // -
int FALOAD = 48; // -
int DALOAD = 49; // -
int AALOAD = 50; // -
int BALOAD = 51; // -
int CALOAD = 52; // -
int SALOAD = 53; // -
int ISTORE = 54; // visitVarInsn
int LSTORE = 55; // -
int FSTORE = 56; // -
int DSTORE = 57; // -
int ASTORE = 58; // -
int IASTORE = 79; // visitInsn
int LASTORE = 80; // -
int FASTORE = 81; // -
int DASTORE = 82; // -
int AASTORE = 83; // -
int BASTORE = 84; // -
int CASTORE = 85; // -
int SASTORE = 86; // -
int POP = 87; // -
int POP2 = 88; // -
int DUP = 89; // -
int DUP_X1 = 90; // -
int DUP_X2 = 91; // -
int DUP2 = 92; // -
int DUP2_X1 = 93; // -
int DUP2_X2 = 94; // -
int SWAP = 95; // -
int IADD = 96; // -
int LADD = 97; // -
int FADD = 98; // -
int DADD = 99; // -
int ISUB = 100; // -
int LSUB = 101; // -
int FSUB = 102; // -
int DSUB = 103; // -
int IMUL = 104; // -
int LMUL = 105; // -
int FMUL = 106; // -
int DMUL = 107; // -
int IDIV = 108; // -
int LDIV = 109; // -
int FDIV = 110; // -
int DDIV = 111; // -
int IREM = 112; // -
int LREM = 113; // -
int FREM = 114; // -
int DREM = 115; // -
int INEG = 116; // -
int LNEG = 117; // -
int FNEG = 118; // -
int DNEG = 119; // -
int ISHL = 120; // -
int LSHL = 121; // -
int ISHR = 122; // -
int LSHR = 123; // -
int IUSHR = 124; // -
int LUSHR = 125; // -
int IAND = 126; // -
int LAND = 127; // -
int IOR = 128; // -
int LOR = 129; // -
int IXOR = 130; // -
int LXOR = 131; // -
int IINC = 132; // visitIincInsn
int I2L = 133; // visitInsn
int I2F = 134; // -
int I2D = 135; // -
int L2I = 136; // -
int L2F = 137; // -
int L2D = 138; // -
int F2I = 139; // -
int F2L = 140; // -
int F2D = 141; // -
int D2I = 142; // -
int D2L = 143; // -
int D2F = 144; // -
int I2B = 145; // -
int I2C = 146; // -
int I2S = 147; // -
int LCMP = 148; // -
int FCMPL = 149; // -
int FCMPG = 150; // -
int DCMPL = 151; // -
int DCMPG = 152; // -
int IFEQ = 153; // visitJumpInsn
int IFNE = 154; // -
int IFLT = 155; // -
int IFGE = 156; // -
int IFGT = 157; // -
int IFLE = 158; // -
int IF_ICMPEQ = 159; // -
int IF_ICMPNE = 160; // -
int IF_ICMPLT = 161; // -
int IF_ICMPGE = 162; // -
int IF_ICMPGT = 163; // -
int IF_ICMPLE = 164; // -
int IF_ACMPEQ = 165; // -
int IF_ACMPNE = 166; // -
int GOTO = 167; // -
int JSR = 168; // -
int RET = 169; // visitVarInsn
int TABLESWITCH = 170; // visiTableSwitchInsn
int LOOKUPSWITCH = 171; // visitLookupSwitch
int IRETURN = 172; // visitInsn
int LRETURN = 173; // -
int FRETURN = 174; // -
int DRETURN = 175; // -
int ARETURN = 176; // -
int RETURN = 177; // -
int GETSTATIC = 178; // visitFieldInsn
int PUTSTATIC = 179; // -
int GETFIELD = 180; // -
int PUTFIELD = 181; // -
int INVOKEVIRTUAL = 182; // visitMethodInsn
int INVOKESPECIAL = 183; // -
int INVOKESTATIC = 184; // -
int INVOKEINTERFACE = 185; // -
int INVOKEDYNAMIC = 186; // visitInvokeDynamicInsn
int NEW = 187; // visitTypeInsn
int NEWARRAY = 188; // visitIntInsn
int ANEWARRAY = 189; // visitTypeInsn
int ARRAYLENGTH = 190; // visitInsn
int ATHROW = 191; // -
int CHECKCAST = 192; // visitTypeInsn
int INSTANCEOF = 193; // -
int MONITORENTER = 194; // visitInsn
int MONITOREXIT = 195; // -
int MULTIANEWARRAY = 197; // visitMultiANewArrayInsn
int IFNULL = 198; // visitJumpInsn
int IFNONNULL = 199; // -
}
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