springboot手动动态注入controller和service方式

目录

• 手动动态注入controller和service
• 在controller中使用参数
• 说明

手动动态注入controller和service

package test;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.beans.factory.config.BeanDefinition;
import org.springframework.beans.factory.support.BeanDefinitionBuilder;
import org.springframework.beans.factory.support.DefaultListableBeanFactory;
import org.springframework.boot.SpringApplication;
import org.springframework.boot.autoconfigure.SpringBootApplication;
import org.springframework.context.ApplicationContext;
import org.springframework.context.ConfigurableApplicationContext;
import org.springframework.core.io.FileSystemResource;
import org.springframework.core.io.FileSystemResourceLoader;
import org.springframework.stereotype.Component;
import org.springframework.util.ClassUtils;
import org.springframework.util.ReflectionUtils;
import org.springframework.util.StringUtils;
import org.springframework.web.servlet.mvc.method.RequestMappingInfo;
import org.springframework.web.servlet.mvc.method.annotation.RequestMappingHandlerMapping;
import java.io.File;
import java.io.FileInputStream;
import java.io.FileNotFoundException;
import java.io.IOException;
import java.lang.reflect.InvocationTargetException;
import java.lang.reflect.Method;
import java.net.MalformedURLException;
import java.net.URL;
import java.net.URLClassLoader;
@SpringBootApplication
@Component
public class ApplicationBootstrap {
    static ApplicationContext applicationContext;
    static String file = "F:\\download\\apache-maven-3.3.9-bin\\repository\\org\\example\\springboot-test-common\\1.0-SNAPSHOT\\" +
            "springboot-test-common-1.0-SNAPSHOT.jar";
    public static void main(String[] args) throws Exception {
        applicationContext = SpringApplication.run(ApplicationBootstrap.class, args);
        String clazzName = "test1.controller.MyTestController1";
        String clazzName1 = "test1.service.MyTestServiceImpl";
        registerBean(clazzName1);
        registerBean(clazzName);
        registerController(StringUtils.uncapitalize(clazzName.substring(clazzName.lastIndexOf(".") + 1)));
    }
    public static void registerBean(String clazzName) throws Exception{
        URL url = new File(file).toURI().toURL();
//        URLClassLoader loader = (URLClassLoader) ApplicationBootstrap.class.getClassLoader();
//        Method add = URLClassLoader.class.getDeclaredMethod("addURL", new Class[] { URL.class });
//        add.setAccessible(true);
//        add.invoke(loader, url);
        URLClassLoader loader = new URLClassLoader(new URL[]{url});
//        String clazzName = "test1.controller.MyTestController1";
        Class<?> clazz = loader.loadClass(clazzName);
//        applicationContext.getClassLoader().loadClass("test.MyController");
//        DefaultListableBeanFactory factory = (DefaultListableBeanFactory) applicationContext.getAutowireCapableBeanFactory();
        BeanDefinitionBuilder beanDefinitionBuilder = BeanDefinitionBuilder.genericBeanDefinition(clazz);
        BeanDefinition beanDefinition = beanDefinitionBuilder.getRawBeanDefinition();
        //设置当前bean定义对象是单利的
        beanDefinition.setScope("singleton");
        //将变量首字母置小写
        String beanName = StringUtils.uncapitalize(clazzName);
        beanName =  beanName.substring(beanName.lastIndexOf(".")+1);
        beanName = StringUtils.uncapitalize(beanName);
        //将applicationContext转换为ConfigurableApplicationContext
        ConfigurableApplicationContext configurableApplicationContext = (ConfigurableApplicationContext) applicationContext;
        // 获取bean工厂并转换为DefaultListableBeanFactory
        DefaultListableBeanFactory defaultListableBeanFactory = (DefaultListableBeanFactory) configurableApplicationContext.getBeanFactory();
        defaultListableBeanFactory.registerBeanDefinition(beanName, beanDefinition);
    }
    /**
     * 注册Controller
     * @param controllerBeanName
     * @throws Exception
     */
    public static void registerController(String controllerBeanName) throws Exception{
        final RequestMappingHandlerMapping requestMappingHandlerMapping=
                applicationContext.getBean(RequestMappingHandlerMapping.class);
        if(requestMappingHandlerMapping!=null){
            String handler=controllerBeanName;
            Object controller= applicationContext.getBean(handler);
            if(controller==null){
                return;
            }
//            unregisterController(controllerBeanName);
            //注册Controller
            Method method=requestMappingHandlerMapping.getClass().getSuperclass().getSuperclass().
                    getDeclaredMethod("detectHandlerMethods",Object.class);
            //将private改为可使用
            method.setAccessible(true);
            method.invoke(requestMappingHandlerMapping,handler);
        }
    }
    /**
     * 去掉Controller的Mapping
     * @param controllerBeanName
     */
    public static void unregisterController(String controllerBeanName){
        final RequestMappingHandlerMapping requestMappingHandlerMapping=(RequestMappingHandlerMapping)
                applicationContext.getBean("requestMappingHandlerMapping");
        if(requestMappingHandlerMapping!=null){
            String handler=controllerBeanName;
            Object controller= applicationContext.getBean(handler);
            if(controller==null){
                return;
            }
            final Class<?> targetClass=controller.getClass();
            ReflectionUtils.doWithMethods(targetClass, new ReflectionUtils.MethodCallback() {
                public void doWith(Method method) {
                    Method specificMethod = ClassUtils.getMostSpecificMethod(method, targetClass);
                    try {
                        Method createMappingMethod = RequestMappingHandlerMapping.class.
                                getDeclaredMethod("getMappingForMethod", Method.class, Class.class);
                        createMappingMethod.setAccessible(true);
                        RequestMappingInfo requestMappingInfo =(RequestMappingInfo)
                                createMappingMethod.invoke(requestMappingHandlerMapping,specificMethod,targetClass);
                        if(requestMappingInfo != null) {
                            requestMappingHandlerMapping.unregisterMapping(requestMappingInfo);
                        }
                    }catch (Exception e){
                        e.printStackTrace();
                    }
                }
            }, ReflectionUtils.USER_DECLARED_METHODS);
        }
    }
}

在controller中使用参数

说明

控制器中使用参数有很多种方式，直接上代码，在代码注释中进行说明

package com.mzj.springboot.actionpai.controller; 
import com.mzj.springboot.actionpai.common.User;
import org.springframework.web.bind.annotation.*;
 
import javax.servlet.http.HttpServletRequest;
import java.util.List;
 
@RestController
public class HelloWorldController3 {
 
    //----------------------方法1、获取路径中的值----------------------------
    /**
     * URL：http://localhost:8081/addUser0/MAZHONGJIA
     *
     * @param username
     * @return
     */
    @GetMapping("/addUser0/{username}")
    public String addUser0(@PathVariable String username) {
        System.out.println("username : " + username);
        return "success0";
    }
 
    //----------------------方法2、获取路径中的参数----------------------------
    /**
     * URL：http://localhost:8081/addUser1?username=mazhongjia
     *
     * @param username
     * @return
     */
    @GetMapping("/addUser1")
    public String addUser1(String username) {
        System.out.println("username : " + username);
        return "success1";
    }
 
    //----------------------方法3、通过bean接收HTTP提交的对象----------------------------
    /**
     * URL：http://localhost:8081/addUser2?username=mazhongjia&age=33
     *
     * @param user
     * @return
     */
    @GetMapping("/addUser2")
    public String addUser2(User user) {
        System.out.println("user ... " + user);
        return "success2";
    }
 
    //----------------------方法4、通过HttpServletRequest接收参数----------------------------
    /**
     * URL：http://localhost:8081/addUser3?username=mazhongjia
     *
     * @param request
     * @return
     */
    @GetMapping("/addUser3")
    public String addUser3(HttpServletRequest request) {
        System.out.println("username ... " + request.getParameter("username"));
        return "success3";
    }
 
    //----------------------方法5、用@RequestParam绑定入参----------------------------
    /**
     * 通过@RequestParam注解绑定入参
     * <p>
     * URL：http://localhost:8081/addUser1?username=mazhongjia
     *
     * @param username
     * @return
     */
    @GetMapping("/addUser4")
    public String addUser4(@RequestParam String username) {
        System.out.println("username : " + username);
        return "success4";
    }
 
    //----------------------方法6、用@RequestBody接收JSON数据----------------------------
    /**
     * URL：http://localhost:8081/addUser5
     * BODY：
     * [
     * {
     * "username": "mazhongjia",
     * "age": "35"
     * },
     * {
     * "username": "huan",
     * "age": "31"
     * }
     * ]
     * <p>
     * 通过@RequestBody接收JSON入参，同时需要设置http的header中Content-Type属性值为【application/json;charset=UTF-8】
     *
     * @param userList
     * @return
     */
    @PostMapping("/addUser5")
    public String addUser5(@RequestBody List<User> userList) {
        System.out.println("userList : " + userList);
        return "success5";
    }
 
    //----------------------方法7、用@ModelAttribute注解获取参数----------------------------
    /**
     * URL：http://localhost:8081/addUser6?username=mazhong&age=35
     * <p>
     * 通过@ModelAttribute注解，从Model、Form或者URL请求参数中获取属性值，上面的URL演示从URL参数中取值
     *
     * @param user
     * @return
     */
    @PostMapping("/addUser6")
    public String addUser6(@ModelAttribute("user") User user) {
        System.out.println("user ... " + user);
        return "success6";
    }
 
    /**
     * URL：http://localhost:8081/addUser7
     * <p>
     * 通过@ModelAttribute注解，从Model、Form或者URL请求参数中获取属性值，上面的URL演示从Model中取值
     *
     * @param user
     * @return
     */
    @PostMapping("/addUser7")
    public String addUser7(@ModelAttribute("user") User user) {
        System.out.println("user7 ... " + user);
        return "success7";
    }
    @ModelAttribute("user")
    public User addAccount() {
        return new User("jz", 55);
    } 
}

除了上面的方式外，还有：上传文件MultipartFile、上传图片，这里省略。

以上为个人经验，希望能给大家一个参考，也希望大家多多支持我们。