Java | リフレクションを通じてクラスとメソッドを呼び出す場合の依存関係注入エラーのトラブルシューティングと解決

情報 2023-07-26 02:55:05 訪問数: null

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序章

  開発プロセス中、リフレクションを使用してクラスのメソッドを呼び出すときに依存性注入の問題が発生しました。この問題はデモを通じて再現および復元され、記録されました。

ベースコード

コントローラクラス

package com.test.selfcoding.controller;

import com.test.selfcoding.service.HelloWorldService;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.web.bind.annotation.GetMapping;
import org.springframework.web.bind.annotation.RequestMapping;
import org.springframework.web.bind.annotation.RestController;

/**
 * @Description controller
 * @Author LiaoJy
 * @Date 2023/6/22
 */
@RestController
@RequestMapping("/hello/world")
public class HelloWorldController {
    
    

    @Autowired
    private HelloWorldService helloWorldService;

    @GetMapping("")
    public String testGetHelloWorld() {
    
    
        return helloWorldService.getHelloWolrd();
    }

}

HelloWorldService クラス

package com.test.selfcoding.service.impl;

import com.test.selfcoding.service.HelloWorldService;
import com.test.selfcoding.utils.RandomStrUtils;
import com.test.selfcoding.utils.SpringContextUtil;
import lombok.SneakyThrows;
import lombok.extern.slf4j.Slf4j;
import org.springframework.stereotype.Service;

import java.lang.reflect.InvocationTargetException;
import java.lang.reflect.Method;

/**
 * @Description HelloWorldService
 * @Author LiaoJy
 * @Date 2023/6/22
 */
@Slf4j
@Service
public class HelloWorldService {
    
    

    public String getHelloWolrd() {
    
    
        String result = this.getStr("getHelloWolrd()");
        if (result.contains("hugh")) {
    
    
            String random = RandomStrUtils.getRandomStr(1);
            return result + random;
        }
        return "hi, someone, hello world!";
    }

    @SneakyThrows
    private String getStr(String methodName) {
    
    
        log.info("{} get str success.", methodName);
        return "hi " + this.getName() + " welcome!";
    }

    private String getName() throws ClassNotFoundException, NoSuchMethodException, InvocationTargetException, IllegalAccessException, InstantiationException {
    
    
        String classPath = "com.test.selfcoding.service.AaService";
        String methodName = "getBbStr";
        String param = "hugh";
        //TODO 反射调用AaService类
    }
}

AaService クラス

package com.test.selfcoding.service;

import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.stereotype.Service;

/**
 * @Description AaService
 * @Author LiaoJy
 * @Date 2023/6/22
 */
@Service
public class AaService {

    @Autowired
    private BbService bbService;

    public String getBbStr(String s) {
        return s + bbService.getBbStr();
    }

}

BbService クラス

package com.test.selfcoding.service;

import org.springframework.stereotype.Service;

/**
 * @Description BbService
 * @Author LiaoJy
 * @Date 2023/6/22
 */
@Service
public class BbService {

    public String getBbStr() {
        return ", hello world！";
    }

}

反省的な練習

反射的な呼び出し

helloWorldService クラスにリフレクション呼び出しを記述する

private String getName() throws ClassNotFoundException, NoSuchMethodException, InvocationTargetException, IllegalAccessException, InstantiationException {
    
    
    String classPath = "com.test.selfcoding.service.AaService";
    String methodName = "getBbStr";
    String param = "hugh";
    //反射
    Class clazz = Class.forName(classPath);
    Method method = clazz.getMethod(methodName, String.class);
    Object obj = SpringContextUtil.getBean(clazz);
    String result = (String) method.invoke(obj, param);
    System.out.println("result: " + result);
    return result;
}

エラー: インスタンス化されていません

  1. ブラウザのアクセスアドレス:http:localhost:8001/hello/world
    画像.png
  2. コンソールは次のエラーを報告します。java.lang.IllegalArgumentException: object is not an instance of declaring class
java.lang.IllegalArgumentException: object is not an instance of declaring class
	at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method) ~[na:1.8.0_301]
	at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:62) ~[na:1.8.0_301]
	at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43) ~[na:1.8.0_301]
	at java.lang.reflect.Method.invoke(Method.java:498) ~[na:1.8.0_301]
	at com.test.selfcoding.service.impl.HelloWorldServiceImpl.getName(HelloWorldServiceImpl.java:47) ~[classes/:na]
	at com.test.selfcoding.service.impl.HelloWorldServiceImpl.getStr(HelloWorldServiceImpl.java:37) ~[classes/:na]
	at com.test.selfcoding.service.impl.HelloWorldServiceImpl.getHelloWolrd(HelloWorldServiceImpl.java:26) ~[classes/:na]
	at com.test.selfcoding.controller.HelloWorldController.testGetHelloWorld(HelloWorldController.java:23) ~[classes/:na]
	at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method) ~[na:1.8.0_301]
	at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:62) ~[na:1.8.0_301]
	at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43) ~[na:1.8.0_301]
	at java.lang.reflect.Method.invoke(Method.java:498) ~[na:1.8.0_301]
	at org.springframework.web.method.support.InvocableHandlerMethod.doInvoke(InvocableHandlerMethod.java:205) ~[spring-web-5.3.21.jar:5.3.21]
	at org.springframework.web.method.support.InvocableHandlerMethod.invokeForRequest(InvocableHandlerMethod.java:150) ~[spring-web-5.3.21.jar:5.3.21]
	at org.springframework.web.servlet.mvc.method.annotation.ServletInvocableHandlerMethod.invokeAndHandle(ServletInvocableHandlerMethod.java:117) ~[spring-webmvc-5.3.21.jar:5.3.21]
	at org.springframework.web.servlet.mvc.method.annotation.RequestMappingHandlerAdapter.invokeHandlerMethod(RequestMappingHandlerAdapter.java:895) ~[spring-webmvc-5.3.21.jar:5.3.21]
	at org.springframework.web.servlet.mvc.method.annotation.RequestMappingHandlerAdapter.handleInternal(RequestMappingHandlerAdapter.java:808) ~[spring-webmvc-5.3.21.jar:5.3.21]
	at org.springframework.web.servlet.mvc.method.AbstractHandlerMethodAdapter.handle(AbstractHandlerMethodAdapter.java:87) ~[spring-webmvc-5.3.21.jar:5.3.21]
	at org.springframework.web.servlet.DispatcherServlet.doDispatch(DispatcherServlet.java:1067) ~[spring-webmvc-5.3.21.jar:5.3.21]
	at org.springframework.web.servlet.DispatcherServlet.doService(DispatcherServlet.java:963) ~[spring-webmvc-5.3.21.jar:5.3.21]
	at org.springframework.web.servlet.FrameworkServlet.processRequest(FrameworkServlet.java:1006) ~[spring-webmvc-5.3.21.jar:5.3.21]
	at org.springframework.web.servlet.FrameworkServlet.doGet(FrameworkServlet.java:898) ~[spring-webmvc-5.3.21.jar:5.3.21]
	at javax.servlet.http.HttpServlet.service(HttpServlet.java:655) ~[tomcat-embed-core-9.0.64.jar:4.0.FR]
	at org.springframework.web.servlet.FrameworkServlet.service(FrameworkServlet.java:883) ~[spring-webmvc-5.3.21.jar:5.3.21]
	at javax.servlet.http.HttpServlet.service(HttpServlet.java:764) ~[tomcat-embed-core-9.0.64.jar:4.0.FR]
	at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:227) ~[tomcat-embed-core-9.0.64.jar:9.0.64]
	at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:162) ~[tomcat-embed-core-9.0.64.jar:9.0.64]
	at org.apache.tomcat.websocket.server.WsFilter.doFilter(WsFilter.java:53) ~[tomcat-embed-websocket-9.0.64.jar:9.0.64]
	at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:189) ~[tomcat-embed-core-9.0.64.jar:9.0.64]
	at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:162) ~[tomcat-embed-core-9.0.64.jar:9.0.64]
	at org.springframework.web.filter.RequestContextFilter.doFilterInternal(RequestContextFilter.java:100) ~[spring-web-5.3.21.jar:5.3.21]
	at org.springframework.web.filter.OncePerRequestFilter.doFilter(OncePerRequestFilter.java:117) ~[spring-web-5.3.21.jar:5.3.21]
	at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:189) ~[tomcat-embed-core-9.0.64.jar:9.0.64]
	at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:162) ~[tomcat-embed-core-9.0.64.jar:9.0.64]
	at org.springframework.web.filter.FormContentFilter.doFilterInternal(FormContentFilter.java:93) ~[spring-web-5.3.21.jar:5.3.21]
	at org.springframework.web.filter.OncePerRequestFilter.doFilter(OncePerRequestFilter.java:117) ~[spring-web-5.3.21.jar:5.3.21]
	at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:189) ~[tomcat-embed-core-9.0.64.jar:9.0.64]
	at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:162) ~[tomcat-embed-core-9.0.64.jar:9.0.64]
	at org.springframework.web.filter.CharacterEncodingFilter.doFilterInternal(CharacterEncodingFilter.java:201) ~[spring-web-5.3.21.jar:5.3.21]
	at org.springframework.web.filter.OncePerRequestFilter.doFilter(OncePerRequestFilter.java:117) ~[spring-web-5.3.21.jar:5.3.21]
	at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:189) ~[tomcat-embed-core-9.0.64.jar:9.0.64]
	at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:162) ~[tomcat-embed-core-9.0.64.jar:9.0.64]
	at org.apache.catalina.core.StandardWrapperValve.invoke(StandardWrapperValve.java:197) ~[tomcat-embed-core-9.0.64.jar:9.0.64]
	at org.apache.catalina.core.StandardContextValve.invoke(StandardContextValve.java:97) [tomcat-embed-core-9.0.64.jar:9.0.64]
	at org.apache.catalina.authenticator.AuthenticatorBase.invoke(AuthenticatorBase.java:541) [tomcat-embed-core-9.0.64.jar:9.0.64]
	at org.apache.catalina.core.StandardHostValve.invoke(StandardHostValve.java:135) [tomcat-embed-core-9.0.64.jar:9.0.64]
	at org.apache.catalina.valves.ErrorReportValve.invoke(ErrorReportValve.java:92) [tomcat-embed-core-9.0.64.jar:9.0.64]
	at org.apache.catalina.core.StandardEngineValve.invoke(StandardEngineValve.java:78) [tomcat-embed-core-9.0.64.jar:9.0.64]
	at org.apache.catalina.connector.CoyoteAdapter.service(CoyoteAdapter.java:360) [tomcat-embed-core-9.0.64.jar:9.0.64]
	at org.apache.coyote.http11.Http11Processor.service(Http11Processor.java:399) [tomcat-embed-core-9.0.64.jar:9.0.64]
	at org.apache.coyote.AbstractProcessorLight.process(AbstractProcessorLight.java:65) [tomcat-embed-core-9.0.64.jar:9.0.64]
	at org.apache.coyote.AbstractProtocol$ConnectionHandler.process(AbstractProtocol.java:890) [tomcat-embed-core-9.0.64.jar:9.0.64]
	at org.apache.tomcat.util.net.NioEndpoint$SocketProcessor.doRun(NioEndpoint.java:1787) [tomcat-embed-core-9.0.64.jar:9.0.64]
	at org.apache.tomcat.util.net.SocketProcessorBase.run(SocketProcessorBase.java:49) [tomcat-embed-core-9.0.64.jar:9.0.64]
	at org.apache.tomcat.util.threads.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1191) [tomcat-embed-core-9.0.64.jar:9.0.64]
	at org.apache.tomcat.util.threads.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:659) [tomcat-embed-core-9.0.64.jar:9.0.64]
	at org.apache.tomcat.util.threads.TaskThread$WrappingRunnable.run(TaskThread.java:61) [tomcat-embed-core-9.0.64.jar:9.0.64]
	at java.lang.Thread.run(Thread.java:748) [na:1.8.0_301]

解決してみてください: インスタンス化

Class clazz = Class.forName(classPath);
Method method = clazz.getMethod(methodName, String.class);
Object obj = clazz.newInstance();
String result = (String) method.invoke(obj, param);

エラー: null ポインタ

  1. ブラウザのアクセスアドレス:http:localhost:8001/hello/world
    画像.png
  2. コンソールは次のエラーを報告します。java.lang.NullPointerException: null
java.lang.NullPointerException: null
	at com.test.selfcoding.service.AaService.getBbStr(AaService.java:18) ~[classes/:na]
	at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method) ~[na:1.8.0_301]
	at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:62) ~[na:1.8.0_301]
	at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43) ~[na:1.8.0_301]
	at java.lang.reflect.Method.invoke(Method.java:498) ~[na:1.8.0_301]
	at com.test.selfcoding.service.impl.HelloWorldServiceImpl.getName(HelloWorldServiceImpl.java:48) ~[classes/:na]
	at com.test.selfcoding.service.impl.HelloWorldServiceImpl.getStr(HelloWorldServiceImpl.java:37) ~[classes/:na]
	at com.test.selfcoding.service.impl.HelloWorldServiceImpl.getHelloWolrd(HelloWorldServiceImpl.java:26) ~[classes/:na]
	at com.test.selfcoding.controller.HelloWorldController.testGetHelloWorld(HelloWorldController.java:23) ~[classes/:na]
	at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method) ~[na:1.8.0_301]
	at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:62) ~[na:1.8.0_301]
	at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43) ~[na:1.8.0_301]
	at java.lang.reflect.Method.invoke(Method.java:498) ~[na:1.8.0_301]
	at org.springframework.web.method.support.InvocableHandlerMethod.doInvoke(InvocableHandlerMethod.java:205) ~[spring-web-5.3.21.jar:5.3.21]
	at org.springframework.web.method.support.InvocableHandlerMethod.invokeForRequest(InvocableHandlerMethod.java:150) ~[spring-web-5.3.21.jar:5.3.21]
	at org.springframework.web.servlet.mvc.method.annotation.ServletInvocableHandlerMethod.invokeAndHandle(ServletInvocableHandlerMethod.java:117) ~[spring-webmvc-5.3.21.jar:5.3.21]
	at org.springframework.web.servlet.mvc.method.annotation.RequestMappingHandlerAdapter.invokeHandlerMethod(RequestMappingHandlerAdapter.java:895) ~[spring-webmvc-5.3.21.jar:5.3.21]
	at org.springframework.web.servlet.mvc.method.annotation.RequestMappingHandlerAdapter.handleInternal(RequestMappingHandlerAdapter.java:808) ~[spring-webmvc-5.3.21.jar:5.3.21]
	at org.springframework.web.servlet.mvc.method.AbstractHandlerMethodAdapter.handle(AbstractHandlerMethodAdapter.java:87) ~[spring-webmvc-5.3.21.jar:5.3.21]
	at org.springframework.web.servlet.DispatcherServlet.doDispatch(DispatcherServlet.java:1067) ~[spring-webmvc-5.3.21.jar:5.3.21]
	at org.springframework.web.servlet.DispatcherServlet.doService(DispatcherServlet.java:963) ~[spring-webmvc-5.3.21.jar:5.3.21]
	at org.springframework.web.servlet.FrameworkServlet.processRequest(FrameworkServlet.java:1006) ~[spring-webmvc-5.3.21.jar:5.3.21]
	at org.springframework.web.servlet.FrameworkServlet.doGet(FrameworkServlet.java:898) ~[spring-webmvc-5.3.21.jar:5.3.21]
	at javax.servlet.http.HttpServlet.service(HttpServlet.java:655) ~[tomcat-embed-core-9.0.64.jar:4.0.FR]
	at org.springframework.web.servlet.FrameworkServlet.service(FrameworkServlet.java:883) ~[spring-webmvc-5.3.21.jar:5.3.21]
	at javax.servlet.http.HttpServlet.service(HttpServlet.java:764) ~[tomcat-embed-core-9.0.64.jar:4.0.FR]
	at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:227) ~[tomcat-embed-core-9.0.64.jar:9.0.64]
	at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:162) ~[tomcat-embed-core-9.0.64.jar:9.0.64]
	at org.apache.tomcat.websocket.server.WsFilter.doFilter(WsFilter.java:53) ~[tomcat-embed-websocket-9.0.64.jar:9.0.64]
	at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:189) ~[tomcat-embed-core-9.0.64.jar:9.0.64]
	at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:162) ~[tomcat-embed-core-9.0.64.jar:9.0.64]
	at org.springframework.web.filter.RequestContextFilter.doFilterInternal(RequestContextFilter.java:100) ~[spring-web-5.3.21.jar:5.3.21]
	at org.springframework.web.filter.OncePerRequestFilter.doFilter(OncePerRequestFilter.java:117) ~[spring-web-5.3.21.jar:5.3.21]
	at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:189) ~[tomcat-embed-core-9.0.64.jar:9.0.64]
	at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:162) ~[tomcat-embed-core-9.0.64.jar:9.0.64]
	at org.springframework.web.filter.FormContentFilter.doFilterInternal(FormContentFilter.java:93) ~[spring-web-5.3.21.jar:5.3.21]
	at org.springframework.web.filter.OncePerRequestFilter.doFilter(OncePerRequestFilter.java:117) ~[spring-web-5.3.21.jar:5.3.21]
	at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:189) ~[tomcat-embed-core-9.0.64.jar:9.0.64]
	at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:162) ~[tomcat-embed-core-9.0.64.jar:9.0.64]
	at org.springframework.web.filter.CharacterEncodingFilter.doFilterInternal(CharacterEncodingFilter.java:201) ~[spring-web-5.3.21.jar:5.3.21]
	at org.springframework.web.filter.OncePerRequestFilter.doFilter(OncePerRequestFilter.java:117) ~[spring-web-5.3.21.jar:5.3.21]
	at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:189) ~[tomcat-embed-core-9.0.64.jar:9.0.64]
	at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:162) ~[tomcat-embed-core-9.0.64.jar:9.0.64]
	at org.apache.catalina.core.StandardWrapperValve.invoke(StandardWrapperValve.java:197) ~[tomcat-embed-core-9.0.64.jar:9.0.64]
	at org.apache.catalina.core.StandardContextValve.invoke(StandardContextValve.java:97) [tomcat-embed-core-9.0.64.jar:9.0.64]
	at org.apache.catalina.authenticator.AuthenticatorBase.invoke(AuthenticatorBase.java:541) [tomcat-embed-core-9.0.64.jar:9.0.64]
	at org.apache.catalina.core.StandardHostValve.invoke(StandardHostValve.java:135) [tomcat-embed-core-9.0.64.jar:9.0.64]
	at org.apache.catalina.valves.ErrorReportValve.invoke(ErrorReportValve.java:92) [tomcat-embed-core-9.0.64.jar:9.0.64]
	at org.apache.catalina.core.StandardEngineValve.invoke(StandardEngineValve.java:78) [tomcat-embed-core-9.0.64.jar:9.0.64]
	at org.apache.catalina.connector.CoyoteAdapter.service(CoyoteAdapter.java:360) [tomcat-embed-core-9.0.64.jar:9.0.64]
	at org.apache.coyote.http11.Http11Processor.service(Http11Processor.java:399) [tomcat-embed-core-9.0.64.jar:9.0.64]
	at org.apache.coyote.AbstractProcessorLight.process(AbstractProcessorLight.java:65) [tomcat-embed-core-9.0.64.jar:9.0.64]
	at org.apache.coyote.AbstractProtocol$ConnectionHandler.process(AbstractProtocol.java:890) [tomcat-embed-core-9.0.64.jar:9.0.64]
	at org.apache.tomcat.util.net.NioEndpoint$SocketProcessor.doRun(NioEndpoint.java:1787) [tomcat-embed-core-9.0.64.jar:9.0.64]
	at org.apache.tomcat.util.net.SocketProcessorBase.run(SocketProcessorBase.java:49) [tomcat-embed-core-9.0.64.jar:9.0.64]
	at org.apache.tomcat.util.threads.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1191) [tomcat-embed-core-9.0.64.jar:9.0.64]
	at org.apache.tomcat.util.threads.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:659) [tomcat-embed-core-9.0.64.jar:9.0.64]
	at org.apache.tomcat.util.threads.TaskThread$WrappingRunnable.run(TaskThread.java:61) [tomcat-embed-core-9.0.64.jar:9.0.64]
	at java.lang.Thread.run(Thread.java:748) [na:1.8.0_301]

デバッグビュー

画像.png
bbService には注入されず、空です。

Bean が持っているかどうかを確認します。

起動時にコンテキスト内で beanFactory-"beanDefinitionMap" を表示します。

画像.png
aaService と bbService があります

画像.png

最終的解決

リフレクション呼び出し時にコンテキスト内で Bean を取得し、依存関係注入の問題を解決します。

SpringContextUtil ツールクラス


/**
 * @Description 上下文工具类
 * @Author LiaoJy
 * @Date 2023/6/22
 */
@Component
public class SpringContextUtil implements ApplicationContextAware {
    
    

    private static ApplicationContext applicationContext;

    @Override
    public void setApplicationContext(ApplicationContext applicationContext) throws BeansException {
    
    
        SpringContextUtil.applicationContext = applicationContext;
    }

    public static <T> T getBean(Class<T> clazz) {
    
    
        // 先判断是否存在上下文对象
        if (applicationContext == null) {
    
    
            return null;
        }
        return applicationContext.getBean(clazz);
    }

    public static <T> T getBean(String beanName, Class<T> clazz) {
    
    
        // 先判断是否存在上下文对象
        if (applicationContext == null) {
    
    
            return null;
        }
        return applicationContext.getBean(beanName, clazz);
    }

}

リフレクションが呼び出されたときにコンテキストを通じて Bean を取得します

Class clazz = Class.forName(classPath);
Method method = clazz.getMethod(methodName, String.class);
Object obj = SpringContextUtil.getBean(clazz);
String result = (String) method.invoke(obj, param);

演算結果

  1. ブラウザのアクセスアドレス:http:localhost:8001/hello/world
    画像.png
  2. コンソール情報
2023-06-22 18:07:29.189  INFO 19952 --- [nio-8001-exec-1] c.t.s.s.impl.HelloWorldServiceImpl       : getHelloWolrd() get str success.
result: hugh, hello world！

これまでのところ、問題は解決しました！

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