这里续写上一章博客（110章博客）：
现在我们来学习一下高级的技术，前面的mvc知识，我们基本可以在67章博客及其后面相关的博客可以学习到，现在开始学习精髓：
< packaging> </ packaging> < dependencies> < dependency> < groupId> </ groupId> < artifactId> </ artifactId> < version> </ version> </ dependency> < dependency> < groupId> </ groupId> < artifactId> </ artifactId> < version> </ version> </ dependency> < dependency> < groupId> </ groupId> < artifactId> </ artifactId> < version> </ version> </ dependency> < dependency> < groupId> </ groupId> < artifactId> </ artifactId> < version> </ version> </ dependency> < dependency> < groupId> </ groupId> < artifactId> </ artifactId> < version> </ version> </ dependency> </ dependencies> <?xml version="1.0" encoding="UTF-8"?>
< web-appxmlns = " http://xmlns.jcp.org/xml/ns/javaee" xmlns: xsi= " http://www.w3.org/2001/XMLSchema-instance" xsi: schemaLocation= " http://xmlns.jcp.org/xml/ns/javaee http://xmlns.jcp.org/xml/ns/javaee/web-app_4_0.xsd" version = " 4.0" > < servlet> < servlet-name> </ servlet-name> < servlet-class> </ servlet-class> < init-param> < param-name> </ param-name> < param-value> </ param-value> </ init-param> </ servlet> < servlet-mapping> < servlet-name> </ servlet-name> < url-pattern> </ url-pattern> </ servlet-mapping> </ web-app> <%@ page contentType="text/html;charset=UTF-8" language="java" %>
<html>
<head>
<title>Title</title>
</head>
<body>
<script src="https://code.jquery.com/jquery-3.6.0.min.js"></script>
<button id="btn">ajax提交</button>
<script>
$("#btn").click(function () {
let url = 'test/in';
let data = '[{"id":1,"username":"张三"},{"id":2,"username":"李四"}]';
$.ajax({
type: 'POST',//大小写可以忽略
url: url,
data: data,
contentType: 'application/json;charset=utf-8',
success: function (data) {
console.log(data);
alert(data)
}
})
})
</script>
</body>
</html>
< beansxmlns = " http://www.springframework.org/schema/beans" xmlns: mvc= " http://www.springframework.org/schema/mvc" xmlns: context= " http://www.springframework.org/schema/context" xmlns: xsi= " http://www.w3.org/2001/XMLSchema-instance" xsi: schemaLocation= " http://www.springframework.org/schema/beans
http://www.springframework.org/schema/beans/spring-beans.xsd
http://www.springframework.org/schema/context
http://www.springframework.org/schema/context/spring-context.xsd
http://www.springframework.org/schema/mvc
http://www.springframework.org/schema/mvc/spring-mvc.xsd" > < context: component-scanbase-package = " com.controller" /> < mvc: annotation-driven> </ mvc: annotation-driven> </ beans> package com. entity ;
public class User {
String id;
String username;
public String getId ( ) {
return id;
}
public void setId ( String id) {
this . id = id;
}
public String getUsername ( ) {
return username;
}
public void setUsername ( String username) {
this . username = username;
}
@Override
public String toString ( ) {
return "User{" +
"id='" + id + '\'' +
", username='" + username + '\'' +
'}' ;
}
}
package com. controller ;
import com. entity. User ;
import org. springframework. stereotype. Controller ;
import org. springframework. web. bind. annotation. RequestBody ;
import org. springframework. web. bind. annotation. RequestMapping ;
import org. springframework. web. bind. annotation. ResponseBody ;
import java. util. List ;
@Controller
@RequestMapping ( "/test" )
public class test {
@RequestMapping ( "in" )
@ResponseBody
public List < User > ajax ( @RequestBody List < User > ) {
System . out. println ( list) ;
return list;
}
}
package com. Interceptor ;
import org. springframework. web. servlet. HandlerInterceptor ;
public class MyInterceptor implements HandlerInterceptor {
}
package org. springframework. web. servlet ;
import javax. servlet. http. HttpServletRequest ;
import javax. servlet. http. HttpServletResponse ;
import org. springframework. lang. Nullable ;
public interface HandlerInterceptor {
default boolean preHandle ( HttpServletRequest request, HttpServletResponse response, Object handler) throws Exception {
return true ;
}
default void postHandle ( HttpServletRequest request, HttpServletResponse response, Object handler, @Nullable ModelAndView modelAndView) throws Exception {
}
default void afterCompletion ( HttpServletRequest request, HttpServletResponse response, Object handler, @Nullable Exception ex) throws Exception {
}
}
package com. Interceptor ;
import org. springframework. web. servlet. HandlerInterceptor ;
import org. springframework. web. servlet. ModelAndView ;
import javax. servlet. http. HttpServletRequest ;
import javax. servlet. http. HttpServletResponse ;
public class MyInterceptor implements HandlerInterceptor {
@Override
public boolean preHandle ( HttpServletRequest request, HttpServletResponse response, Object handler) throws Exception {
System . out. println ( handler) ;
System . out. println ( "Handler业务逻辑执行之前拦截一次，我是第一次" ) ;
return true ;
}
@Override
public void postHandle ( HttpServletRequest request, HttpServletResponse response, Object handler, ModelAndView modelAndView) throws Exception {
System . out. println ( handler) ;
System . out. println ( modelAndView) ;
System . out. println ( "在Handler逻辑执行完毕但未跳转页面之前拦截一次，我是第二次" ) ;
}
@Override
public void afterCompletion ( HttpServletRequest request, HttpServletResponse response, Object handler, Exception ex) throws Exception {
System . out. println ( handler) ;
System . out. println ( ex) ;
System . out. println ( "在跳转页面之后拦截一次，我是第三次" ) ;
}
}
< mvc: interceptors> < mvc: interceptor> < mvc: mappingpath = " /**" /> < beanclass = " com.Interceptor.MyInterceptor" > </ bean> </ mvc: interceptor> </ mvc: interceptors> < mvc: interceptors> < beanclass = " com.Interceptor.MyInterceptor" > </ bean> </ mvc: interceptors>
< mvc: interceptors> < mvc: interceptor> < mvc: mappingpath = " /**" /> < beanclass = " com.Interceptor.MyInterceptor" > </ bean> </ mvc: interceptor> </ mvc: interceptors> < mvc: interceptors> < mvc: interceptor> < mvc: mappingpath = " /**" /> < mvc: exclude-mappingpath = " /demo/**" /> < beanclass = " com.Interceptor.MyInterceptor" > </ bean> </ mvc: interceptor> </ mvc: interceptors>
<%@ page contentType="text/html;charset=UTF-8" language="java" %>
<html>
<head>
<title>Title</title>
</head>
<body>
<%
System.out.println(1);
%>
1
</script>
</body>
</html>
<%
System.out.println(1);
%>
< beanid = " viewResolver" class = " org.springframework.web.servlet.view.InternalResourceViewResolver" > < propertyname = " prefix" value = " /" > </ property> < propertyname = " suffix" value = " .jsp" > </ property> </ bean> @RequestMapping ( "ix" )
public String ix ( ) {
return "test" ;
}
public String ix ( String a, Integer b) {
@RequestMapping ( "ix" )
public void ix ( String a, Integer b) {
}
@RequestMapping ( "ix" )
public String ix ( String a, Integer b) throws IOException {
return null ;
}
@RequestMapping ( "ix" )
public void ix ( String a, Integer b, HttpServletResponse mm) throws IOException {
mm. setContentType ( "text/html;charset=utf-8" ) ;
PrintWriter writer = mm. getWriter ( ) ;
writer. println ( "哈哈哈" ) ;
}
@RequestMapping ( "ix" )
public void ix ( String a, Integer b, HttpServletResponse mm) throws IOException {
}
package com. Interceptor ;
import org. springframework. web. servlet. HandlerInterceptor ;
import org. springframework. web. servlet. ModelAndView ;
import javax. servlet. http. HttpServletRequest ;
import javax. servlet. http. HttpServletResponse ;
public class MyInterceptor1 implements HandlerInterceptor {
@Override
public boolean preHandle ( HttpServletRequest request, HttpServletResponse response, Object
handler) throws Exception {
System . out. println ( "preHandle1...." ) ;
return true ;
}
@Override
public void postHandle ( HttpServletRequest request, HttpServletResponse response, Object handler,
ModelAndView modelAndView) throws Exception {
System . out. println ( "postHandle1...." ) ;
}
@Override
public void afterCompletion ( HttpServletRequest request, HttpServletResponse response, Object
handler, Exception ex) throws Exception {
System . out. println ( "afterCompletion1...." ) ;
}
}
package com. Interceptor ;
import org. springframework. web. servlet. HandlerInterceptor ;
import org. springframework. web. servlet. ModelAndView ;
import javax. servlet. http. HttpServletRequest ;
import javax. servlet. http. HttpServletResponse ;
public class MyInterceptor2 implements HandlerInterceptor {
@Override
public boolean preHandle ( HttpServletRequest request, HttpServletResponse response, Object
handler) throws Exception {
System . out. println ( "preHandle2...." ) ;
return true ;
}
@Override
public void postHandle ( HttpServletRequest request, HttpServletResponse response, Object handler,
ModelAndView modelAndView) throws Exception {
System . out. println ( "postHandle2...." ) ;
}
@Override
public void afterCompletion ( HttpServletRequest request, HttpServletResponse response, Object
handler, Exception ex) throws Exception {
System . out. println ( "afterCompletion2...." ) ;
}
}
< mvc: interceptors> < mvc: interceptor> < mvc: mappingpath = " /**" /> < beanclass = " com.Interceptor.MyInterceptor1" > </ bean> </ mvc: interceptor> < mvc: interceptor> < mvc: mappingpath = " /**" /> < beanclass = " com.Interceptor.MyInterceptor2" > </ bean> </ mvc: interceptor> </ mvc: interceptors> < beanid = " viewResolver" class = " org.springframework.web.servlet.view.InternalResourceViewResolver" > < propertyname = " prefix" value = " /" > </ property> < propertyname = " suffix" value = " .jsp" > </ property> </ bean> @RequestMapping ( "ix" )
public String ix ( String a, Integer b) throws IOException {
return "test" ;
}
< mvc: interceptors> < mvc: interceptor> < mvc: mappingpath = " /**" /> < beanclass = " com.Interceptor.MyInterceptor2" > </ bean> </ mvc: interceptor> < mvc: interceptor> < mvc: mappingpath = " /**" /> < beanclass = " com.Interceptor.MyInterceptor1" > </ bean> </ mvc: interceptor> </ mvc: interceptors>
package com. Interceptor ;
import org. springframework. web. servlet. HandlerInterceptor ;
import org. springframework. web. servlet. ModelAndView ;
import javax. servlet. http. HttpServletRequest ;
import javax. servlet. http. HttpServletResponse ;
public class MyInterceptor3 implements HandlerInterceptor {
@Override
public boolean preHandle ( HttpServletRequest request, HttpServletResponse response, Object
handler) throws Exception {
System . out. println ( "preHandle3...." ) ;
return false ;
}
@Override
public void postHandle ( HttpServletRequest request, HttpServletResponse response, Object handler,
ModelAndView modelAndView) throws Exception {
System . out. println ( "postHandle3...." ) ;
}
@Override
public void afterCompletion ( HttpServletRequest request, HttpServletResponse response, Object
handler, Exception ex) throws Exception {
System . out. println ( "afterCompletion3...." ) ;
}
}
< mvc: interceptors> < mvc: interceptor> < mvc: mappingpath = " /**" /> < beanclass = " com.Interceptor.MyInterceptor1" > </ bean> </ mvc: interceptor> < mvc: interceptor> < mvc: mappingpath = " /**" /> < beanclass = " com.Interceptor.MyInterceptor3" > </ bean> </ mvc: interceptor> < mvc: interceptor> < mvc: mappingpath = " /**" /> < beanclass = " com.Interceptor.MyInterceptor2" > </ bean> </ mvc: interceptor> </ mvc: interceptors>
< mvc: interceptors> < mvc: interceptor> < mvc: mappingpath = " /**" /> < beanclass = " com.Interceptor.MyInterceptor1" > </ bean> </ mvc: interceptor> < mvc: interceptor> < mvc: mappingpath = " /**" /> < beanclass = " com.Interceptor.MyInterceptor2" > </ bean> </ mvc: interceptor> < mvc: interceptor> < mvc: mappingpath = " /**" /> < beanclass = " com.Interceptor.MyInterceptor3" > </ bean> </ mvc: interceptor> </ mvc: interceptors>
< dependency> < groupId> </ groupId> < artifactId> </ artifactId> < version> </ version> </ dependency> < beanid = " multipartResolver" class = " org.springframework.web.multipart.commons.CommonsMultipartResolver" > < propertyname = " maxUploadSize" value = " 1000000000" /> </ bean> <%@ page contentType="text/html;charset=UTF-8" language="java" %>
<html>
<head>
<title>Title</title>
</head>
<body>
<form method="post" enctype="multipart/form-data" action="demo/upload">
<input type="file" name="uploadFile"/>
<input type="submit" value="上传"/>
</form>
</body>
</html>
package com. controller ;
import org. springframework. stereotype. Controller ;
import org. springframework. web. bind. annotation. RequestMapping ;
import org. springframework. web. multipart. MultipartFile ;
import javax. servlet. http. HttpServletRequest ;
import java. io. File ;
import java. io. IOException ;
import java. text. SimpleDateFormat ;
import java. util. Date ;
import java. util. UUID ;
@Controller
@RequestMapping ( "/demo" )
public class FileController {
@RequestMapping ( "upload" )
public String upload ( MultipartFile uploadFile, HttpServletRequest request) throws IOException {
String originalFilename = uploadFile. getOriginalFilename ( ) ;
String extendName =
originalFilename. substring ( originalFilename. lastIndexOf ( "." ) + 1 , originalFilename. length ( ) ) ;
String uuid = UUID . randomUUID ( ) . toString ( ) ;
String newName = uuid + "." + extendName;
String realPath =
request. getSession ( ) . getServletContext ( ) . getRealPath ( "/" ) ;
System . out. println ( realPath) ;
String datePath = new SimpleDateFormat ( "yyyy-MM-dd" ) . format ( new Date ( ) ) ;
File floder = new File ( realPath + "/" + datePath) ;
if ( ! floder. exists ( ) ) {
floder. mkdirs ( ) ;
}
uploadFile. transferTo ( new File ( floder, newName) ) ;
return "success" ;
}
}
<%@ page contentType="text/html;charset=UTF-8" language="java" %>
<html>
<head>
<title>Title</title>
</head>
<body>
1
</body>
</html>
<?xml version="1.0" encoding="UTF-8"?>
< web-appxmlns = " http://xmlns.jcp.org/xml/ns/javaee" xmlns: xsi= " http://www.w3.org/2001/XMLSchema-instance" xsi: schemaLocation= " http://xmlns.jcp.org/xml/ns/javaee http://xmlns.jcp.org/xml/ns/javaee/web-app_4_0.xsd" version = " 4.0" > < servlet> < servlet-name> </ servlet-name> < servlet-class> </ servlet-class> </ servlet> < servlet-mapping> < servlet-name> </ servlet-name> < url-pattern> </ url-pattern> </ servlet-mapping> </ web-app> @Override
public void service ( ServletRequest servletRequest, ServletResponse servletResponse) throws ServletException , IOException {
String realPath = servletRequest. getServletContext ( ) . getRealPath ( "/" ) ;
System . out. println ( realPath) ;
}
F : \xianmu\out\artifacts\xianmu_Web_exploded\
C : \Users \33988 \AppData \Local \JetBrains \IntelliJIdea2021 .3 \tomcat\062 b022d- 1657 - 4d 8 b- b4e9- da3eeae3d227\conf\Catalina \localhost
<?xml version="1.0" encoding="UTF-8"?>
< projectxmlns = " http://maven.apache.org/POM/4.0.0" xmlns: xsi= " http://www.w3.org/2001/XMLSchema-instance" xsi: schemaLocation= " http://maven.apache.org/POM/4.0.0 http://maven.apache.org/xsd/maven-4.0.0.xsd" > < modelVersion> </ modelVersion> < groupId> </ groupId> < artifactId> </ artifactId> < version> </ version> < properties> < maven.compiler.source> </ maven.compiler.source> < maven.compiler.target> </ maven.compiler.target> </ properties> </ project>
< packaging> </ packaging>
< dependencies> < dependency> < groupId> </ groupId> < artifactId> </ artifactId> < version> </ version> < scope> </ scope> </ dependency> </ dependencies>
< Contextpath = " /maven" docBase = " F:\maven\target\maven-1.0-SNAPSHOT.war" /> F : \Program Files \apache- tomcat- 8.5 .50 \webapps\maven\
< Contextpath = " /maven" docBase = " F:\maven\target\maven-1.0-SNAPSHOT" /> F:\maven\target\maven-1.0-SNAPSHOT\
<Context path="/xianmu" docBase="F:\xianmu\out\artifacts\xianmu_Web_exploded" />
F:\xianmu\out\artifacts\xianmu_Web_exploded\
String realPath = servletRequest. getServletContext ( ) . getRealPath ( "/" ) ;
String realPath = servletRequest. getServletContext ( ) . getRealPath ( "" ) ;
package com. controller ;
import org. springframework. stereotype. Controller ;
import org. springframework. web. bind. annotation. RequestMapping ;
import org. springframework. web. multipart. MultipartFile ;
import javax. servlet. http. HttpServletRequest ;
import java. io. File ;
import java. io. IOException ;
import java. text. SimpleDateFormat ;
import java. util. Date ;
import java. util. UUID ;
@Controller
@RequestMapping ( "/demo" )
public class FileController {
@RequestMapping ( "upload" )
public String upload ( MultipartFile uploadFile, HttpServletRequest request) throws IOException {
String originalFilename = uploadFile. getOriginalFilename ( ) ;
String extendName =
originalFilename. substring ( originalFilename. lastIndexOf ( "." ) + 1 , originalFilename. length ( ) ) ;
String uuid = UUID . randomUUID ( ) . toString ( ) ;
String newName = uuid + "." + extendName;
String realPath =
request. getSession ( ) . getServletContext ( ) . getRealPath ( "/" ) ;
System . out. println ( realPath) ;
String datePath = new SimpleDateFormat ( "yyyy-MM-dd" ) . format ( new Date ( ) ) ;
File floder = new File ( realPath + "/" + datePath) ;
if ( ! floder. exists ( ) ) {
floder. mkdirs ( ) ;
}
uploadFile. transferTo ( new File ( floder, newName) ) ;
return "success" ;
}
}
package com. controller ;
import org. springframework. stereotype. Controller ;
import org. springframework. web. bind. annotation. ControllerAdvice ;
import org. springframework. web. bind. annotation. ExceptionHandler ;
import org. springframework. web. bind. annotation. RequestMapping ;
import org. springframework. web. servlet. ModelAndView ;
import javax. servlet. http. HttpServletResponse ;
import java. io. IOException ;
@Controller
public class GlobalExceptionResolver {
@ExceptionHandler ( ArithmeticException . class )
public ModelAndView handleException ( ArithmeticException exception, HttpServletResponse response) {
ModelAndView modelAndView = new ModelAndView ( ) ;
modelAndView. addObject ( "msg" , exception. getMessage ( ) ) ;
modelAndView. setViewName ( "error" ) ;
return modelAndView;
}
@RequestMapping ( "err" )
public String ix ( String a, Integer b) throws IOException {
System . out. println ( 1 ) ;
int i = 1 / 0 ;
return "err" ;
}
}
<%@ page contentType="text/html;charset=UTF-8" language="java" %>
<html>
<head>
<title>Title</title>
</head>
<body>
错误是：${msg}
</body>
</html>
modelAndView. addObject ( "msg" , exception. getMessage ( ) ) ;
modelAndView. setViewName ( "error" ) ;
@ExceptionHandler ( ArithmeticException . class )
public ModelAndView handleException ( ArithmeticException exception, HttpServletResponse response) {
ModelAndView modelAndView = new ModelAndView ( ) ;
modelAndView. addObject ( "msg" , exception. getMessage ( ) ) ;
modelAndView. setViewName ( "error" ) ;
return modelAndView;
}
@ExceptionHandler ( ArithmeticException . class )
public ModelAndView handleException1 ( ArithmeticException exception, HttpServletResponse response) {
ModelAndView modelAndView = new ModelAndView ( ) ;
modelAndView. addObject ( "msg" , exception. getMessage ( ) + "22" ) ;
modelAndView. setViewName ( "error" ) ;
return modelAndView;
}
package com. controller ;
import org. springframework. stereotype. Controller ;
import org. springframework. web. bind. annotation. ExceptionHandler ;
import org. springframework. web. servlet. ModelAndView ;
import javax. servlet. http. HttpServletResponse ;
@Controller
public class Global {
@ExceptionHandler ( ArithmeticException . class )
public ModelAndView handleException ( ArithmeticException exception, HttpServletResponse response) {
ModelAndView modelAndView = new ModelAndView ( ) ;
modelAndView. addObject ( "msg" , exception. getMessage ( ) ) ;
modelAndView. setViewName ( "error" ) ;
return modelAndView;
}
}
package com. controller ;
import org. springframework. stereotype. Controller ;
import org. springframework. web. bind. annotation. ControllerAdvice ;
import org. springframework. web. bind. annotation. ExceptionHandler ;
import org. springframework. web. servlet. ModelAndView ;
import javax. servlet. http. HttpServletResponse ;
@ControllerAdvice
@Controller
public class Global {
@ExceptionHandler ( ArithmeticException . class )
public ModelAndView handleException ( ArithmeticException exception, HttpServletResponse response) {
ModelAndView modelAndView = new ModelAndView ( ) ;
modelAndView. addObject ( "msg" , exception. getMessage ( ) ) ;
modelAndView. setViewName ( "error" ) ;
return modelAndView;
}
}
package com. controller ;
import org. springframework. stereotype. Controller ;
import org. springframework. web. bind. annotation. RequestMapping ;
@Controller
public class Redirect {
@RequestMapping ( "/re" )
public String re ( ) {
return "redirect:ree?name=" + 1 ;
}
@RequestMapping ( "/ree" )
public String ree ( String name) {
System . out. println ( name) ;
System . out. println ( 1 ) ;
return "ree" ;
}
}
@RequestMapping ( "/reee" )
public String reee ( RedirectAttributes redirectAttributes, HttpSession session) {
redirectAttributes. addFlashAttribute ( "name" , "22" ) ;
Object name = session. getAttribute ( "name" ) ;
System . out. println ( name) ;
return "redirect:reeee?name=" + 1 ;
}
@RequestMapping ( "/reeee" )
public String reeee ( String name, HttpSession session, @ModelAttribute ( "name" ) String na, ModelAndView modelAndView) {
System . out. println ( modelAndView) ;
System . out. println ( na) ;
String name2 = ( String ) session. getAttribute ( "name" ) ;
System . out. println ( name2) ;
System . out. println ( 44444444 ) ;
System . out. println ( name) ;
Object name1 = session. getAttribute ( "name" ) ;
System . out. println ( name1) ;
return "ree" ;
}
< web-app> </ web-app> < dependencies> < dependency> < groupId> </ groupId> < artifactId> </ artifactId> < version> </ version> < scope> </ scope> </ dependency> </ dependencies> package com. mvc. framework ;
import javax. servlet. http. HttpServlet ;
public class DispatcherServlet extends HttpServlet {
}
<?xml version="1.0" encoding="UTF-8"?>
< web-appxmlns = " http://xmlns.jcp.org/xml/ns/javaee" xmlns: xsi= " http://www.w3.org/2001/XMLSchema-instance" xsi: schemaLocation= " http://xmlns.jcp.org/xml/ns/javaee
http://xmlns.jcp.org/xml/ns/javaee/web-app_4_0.xsd" version = " 4.0" > < display-name> </ display-name> < servlet> < servlet-name> </ servlet-name> < servlet-class> </ servlet-class> </ servlet> < servlet-mapping> < servlet-name> </ servlet-name> < url-pattern> </ url-pattern> </ servlet-mapping> </ web-app> package com. mvc. framework. annotations ;
import java. lang. annotation. * ;
@Documented
@Target ( ElementType . TYPE )
@Retention ( RetentionPolicy . RUNTIME )
public @interface Controller {
String value ( ) default "" ;
}
package com. mvc. framework. annotations ;
import java. lang. annotation. * ;
@Documented
@Target ( ElementType . TYPE )
@Retention ( RetentionPolicy . RUNTIME )
public @interface Service {
String value ( ) default "" ;
}
package com. mvc. framework. annotations ;
import java. lang. annotation. * ;
@Documented
@Target ( { ElementType . TYPE , ElementType . METHOD } )
@Retention ( RetentionPolicy . RUNTIME )
public @interface RequestMapping {
String value ( ) default "" ;
}
package com. mvc. framework. annotations ;
import java. lang. annotation. * ;
@Documented
@Target ( ElementType . FIELD )
@Retention ( RetentionPolicy . RUNTIME )
public @interface Autowired {
String value ( ) default "" ;
}
package com. mvc. framework. service ;
public interface DemoService {
String get ( String name) ;
}
package com. mvc. framework. service. impl ;
import com. mvc. framework. service. DemoService ;
public class DemoServiceImpl implements DemoService {
@Override
public String get ( String name) {
System . out. println ( "打印：" + name) ;
return name;
}
}
package com. mvc. framework. servlet ;
import javax. servlet. ServletException ;
import javax. servlet. http. HttpServlet ;
import javax. servlet. http. HttpServletRequest ;
import javax. servlet. http. HttpServletResponse ;
import java. io. IOException ;
public class DispatcherServlet extends HttpServlet {
@Override
public void init ( ServletConfig config) throws ServletException {
}
@Override
protected void doGet ( HttpServletRequest req, HttpServletResponse resp) throws ServletException , IOException {
doPost ( req, resp) ;
}
@Override
protected void doPost ( HttpServletRequest req, HttpServletResponse resp) throws ServletException , IOException {
}
}
@Override
public void init ( ServletConfig config) throws ServletException {
}
< beans> < component-scanbase-package = " com.mvc.framework" /> </ beans> <?xml version="1.0" encoding="UTF-8"?>
< web-appxmlns = " http://xmlns.jcp.org/xml/ns/javaee" xmlns: xsi= " http://www.w3.org/2001/XMLSchema-instance" xsi: schemaLocation= " http://xmlns.jcp.org/xml/ns/javaee
http://xmlns.jcp.org/xml/ns/javaee/web-app_4_0.xsd" version = " 4.0" > < display-name> </ display-name> < servlet> < servlet-name> </ servlet-name> < servlet-class> </ servlet-class> < init-param> < param-name> </ param-name> < param-value> </ param-value> </ init-param> </ servlet> < servlet-mapping> < servlet-name> </ servlet-name> < url-pattern> </ url-pattern> </ servlet-mapping> </ web-app> package com. mvc. framework. servlet ;
import javax. servlet. ServletConfig ;
import javax. servlet. ServletException ;
import javax. servlet. http. HttpServlet ;
import javax. servlet. http. HttpServletRequest ;
import javax. servlet. http. HttpServletResponse ;
import java. io. IOException ;
public class DispatcherServlet extends HttpServlet {
@Override
public void init ( ServletConfig config) throws ServletException {
String contextConfigLocation = config. getInitParameter ( "contextConfigLocation" ) ;
String s = doLoadconfig ( contextConfigLocation) ;
doScan ( s) ;
doInstance ( ) ;
doAutoWired ( ) ;
initHandlerMapping ( ) ;
System . out. println ( "初始化完成...，等待请求与映射匹配了" ) ;
}
private void initHandlerMapping ( ) {
}
private void doAutoWired ( ) {
}
private void doInstance ( ) {
}
private void doScan ( String path) {
}
private String doLoadconfig ( String contextConfigLocation) {
return "" ;
}
@Override
protected void doGet ( HttpServletRequest req, HttpServletResponse resp) throws ServletException , IOException {
doPost ( req, resp) ;
}
@Override
protected void doPost ( HttpServletRequest req, HttpServletResponse resp) throws ServletException , IOException {
}
}
< dependency> < groupId> </ groupId> < artifactId> </ artifactId> < version> </ version> </ dependency> < dependency> < groupId> </ groupId> < artifactId> </ artifactId> < version> </ version> </ dependency> package com. mvc. framework. controller ;
import com. mvc. framework. annotations. Autowired ;
import com. mvc. framework. annotations. Controller ;
import com. mvc. framework. annotations. RequestMapping ;
import com. mvc. framework. service. DemoService ;
import javax. servlet. http. HttpServletRequest ;
import javax. servlet. http. HttpServletResponse ;
@Controller
@RequestMapping ( "/demo" )
public class DemoController {
@Autowired
private DemoService demoService;
@RequestMapping ( "/query" )
public String query ( HttpServletRequest request, HttpServletResponse response, String name) {
String s = demoService. get ( name) ;
return s;
}
}
package com. mvc. framework. servlet ;
import com. mvc. framework. annotations. Autowired ;
import com. mvc. framework. annotations. Controller ;
import com. mvc. framework. annotations. RequestMapping ;
import com. mvc. framework. annotations. Service ;
import org. dom4j. Document ;
import org. dom4j. Element ;
import org. dom4j. io. SAXReader ;
import javax. servlet. ServletConfig ;
import javax. servlet. ServletException ;
import javax. servlet. http. HttpServlet ;
import javax. servlet. http. HttpServletRequest ;
import javax. servlet. http. HttpServletResponse ;
import java. io. File ;
import java. io. IOException ;
import java. io. InputStream ;
import java. lang. reflect. Field ;
import java. lang. reflect. Method ;
import java. net. URLDecoder ;
import java. nio. charset. StandardCharsets ;
import java. util. ArrayList ;
import java. util. HashMap ;
import java. util. List ;
import java. util. Map ;
public class DispatcherServlet extends HttpServlet {
private static List < String > = new ArrayList < > ( ) ;
private static Map < String , Object > = new HashMap < > ( ) ;
private static List < String > = new ArrayList < > ( ) ;
private static Map < String , Method > = new HashMap < > ( ) ;
@Override
public void init ( ServletConfig config) {
String contextConfigLocation = config. getInitParameter ( "contextConfigLocation" ) ;
String s = doLoadconfig ( contextConfigLocation) ;
doScan ( s) ;
doInstance ( ) ;
doAutoWired ( ) ;
initHandlerMapping ( ) ;
System . out. println ( "初始化完成...，等待请求与映射匹配了" ) ;
}
private void initHandlerMapping ( ) {
if ( map. isEmpty ( ) ) {
return ;
}
for ( Map. Entry < String , Object > : map. entrySet ( ) ) {
Class < ? > = entry. getValue ( ) . getClass ( ) ;
if ( aClass. isAnnotationPresent ( Controller . class ) ) {
String baseUrl = "" ;
if ( aClass. isAnnotationPresent ( RequestMapping . class ) ) {
String value = aClass. getAnnotation ( RequestMapping . class ) . value ( ) ;
baseUrl += value;
}
Method [ ] methods = aClass. getMethods ( ) ;
for ( int j = 0 ; j < methods. length; j++ ) {
Method method = methods[ j] ;
if ( method. isAnnotationPresent ( RequestMapping . class ) ) {
RequestMapping annotation = method. getAnnotation ( RequestMapping . class ) ;
String value = annotation. value ( ) ;
String url = baseUrl;
url += value;
handlerMapping. put ( url, method) ;
}
}
}
}
}
private void doAutoWired ( ) {
if ( map. isEmpty ( ) ) {
return ;
}
for ( Map. Entry < String , Object > : map. entrySet ( ) ) {
try {
doObjectDependancy ( entry. getValue ( ) ) ;
} catch ( Exception e) {
e. printStackTrace ( ) ;
}
}
}
private static void doObjectDependancy ( Object object) {
Field [ ] declaredFields = object. getClass ( ) . getDeclaredFields ( ) ;
if ( declaredFields == null || declaredFields. length == 0 ) {
return ;
}
for ( int i = 0 ; i < declaredFields. length; i++ ) {
Field declaredField = declaredFields[ i] ;
if ( ! declaredField. isAnnotationPresent ( Autowired . class ) ) {
continue ;
}
if ( fieldsAlreayProcessed. contains ( object. getClass ( ) . getName ( ) + "." + declaredField. getName ( ) ) ) {
continue ;
}
Object dependObject = null ;
Autowired annotation = declaredField. getAnnotation ( Autowired . class ) ;
String value = annotation. value ( ) ;
if ( "" . equals ( value. trim ( ) ) ) {
dependObject = map. get ( declaredField. getType ( ) . getName ( ) ) ;
if ( dependObject == null ) {
dependObject = map. get ( lowerFirst ( declaredField. getType ( ) . getSimpleName ( ) ) ) ;
}
} else {
dependObject = map. get ( value+ declaredField. getType ( ) . getName ( ) ) ;
}
fieldsAlreayProcessed. add ( object. getClass ( ) . getName ( ) + "." + declaredField. getName ( ) ) ;
if ( dependObject != null ) {
doObjectDependancy ( dependObject) ;
}
declaredField. setAccessible ( true ) ;
try {
declaredField. set ( object, dependObject) ;
} catch ( Exception e) {
e. printStackTrace ( ) ;
}
}
}
private void doInstance ( ) {
if ( classNames. size ( ) == 0 ) return ;
if ( classNames. size ( ) <= 0 ) return ;
try {
for ( int i = 0 ; i < classNames. size ( ) ; i++ ) {
String className = classNames. get ( i) ;
Class < ? > = Class . forName ( className) ;
if ( aClass. isAnnotationPresent ( Controller . class ) ) {
String simpleName = aClass. getSimpleName ( ) ;
String s = lowerFirst ( simpleName) ;
Object o = aClass. newInstance ( ) ;
map. put ( s, o) ;
}
if ( aClass. isAnnotationPresent ( Service . class ) ) {
String beanName = aClass. getAnnotation ( Service . class ) . value ( ) ;
Object o = aClass. newInstance ( ) ;
int ju = 0 ;
if ( "" . equals ( beanName. trim ( ) ) ) {
beanName = lowerFirst ( aClass. getSimpleName ( ) ) ;
} else {
ju= 1 ;
}
if ( ju== 1 ) {
UtilGetClassInterfaces . getkeyClass ( beanName, aClass, map, o) ;
} else {
map. put ( beanName, o) ;
}
Class < ? > [ ] interfaces = aClass. getInterfaces ( ) ;
if ( interfaces != null && interfaces. length > 0 ) {
for ( int j = 0 ; j < interfaces. length; j++ ) {
Class < ? > = interfaces[ j] ;
map. put ( anInterface. getName ( ) , aClass. newInstance ( ) ) ;
}
}
}
}
} catch ( Exception e) {
e. printStackTrace ( ) ;
}
}
private static String lowerFirst ( String str) {
char [ ] chars = str. toCharArray ( ) ;
if ( 'A' <= chars[ 0 ] && chars[ 0 ] <= 'Z' ) {
chars[ 0 ] += 32 ;
}
return String . valueOf ( chars) ;
}
private void doScan ( String scanPackage) {
try {
String scanPackagePath = Thread . currentThread ( ) . getContextClassLoader ( ) . getResource ( "" ) . getPath ( ) + scanPackage. replaceAll ( "\\." , "/" ) ;
scanPackagePath = URLDecoder . decode ( scanPackagePath, StandardCharsets . UTF_8 . toString ( ) ) ;
File pack = new File ( scanPackagePath) ;
File [ ] files = pack. listFiles ( ) ;
for ( File file : files) {
if ( file. isDirectory ( ) ) {
doScan ( scanPackage + "." + file. getName ( ) ) ;
continue ;
}
if ( file. getName ( ) . endsWith ( ".class" ) ) {
String className = scanPackage + "." + file. getName ( ) . replaceAll ( ".class" , "" ) ;
classNames. add ( className) ;
}
}
} catch ( Exception e) {
e. printStackTrace ( ) ;
}
}
private String doLoadconfig ( String contextConfigLocation) {
InputStream resourceAsStream = DispatcherServlet . class . getClassLoader ( ) . getResourceAsStream ( contextConfigLocation) ;
SAXReader saxReader = new SAXReader ( ) ;
try {
Document document = saxReader. read ( resourceAsStream) ;
Element rootElement = document. getRootElement ( ) ;
Element element = ( Element ) rootElement. selectSingleNode ( "//component-scan" ) ;
String attribute = element. attributeValue ( "base-package" ) ;
return attribute;
} catch ( Exception e) {
e. printStackTrace ( ) ;
}
return "" ;
}
@Override
protected void doGet ( HttpServletRequest req, HttpServletResponse resp) throws ServletException , IOException {
doPost ( req, resp) ;
}
@Override
protected void doPost ( HttpServletRequest req, HttpServletResponse resp) throws ServletException , IOException {
System . out. println ( "请求资源的路径为：" + req. getRequestURI ( ) ) ;
System . out. println ( "请求资源的完整路径为：" + req. getRequestURL ( ) ) ;
String requestURI = req. getRequestURI ( ) ;
Method method = handlerMapping. get ( requestURI) ;
}
}
package com. mvc. framework. servlet ;
public class a extends b implements f {
public static void main ( String [ ] args) {
getkeyClass ( a. class ) ;
}
private static void getkeyClass ( Class a) {
Class superclass = a. getSuperclass ( ) ;
if ( "java.lang.Object" . equals ( superclass. getName ( ) ) ) {
System . out. println ( a. getName ( ) ) ;
} else {
System . out. println ( a. getName ( ) ) ;
getkeyClass ( superclass) ;
}
Class [ ] interfaces = a. getInterfaces ( ) ;
for ( Class anInterface : interfaces) {
getkeyInterface ( anInterface) ;
}
}
private static void getkeyInterface ( Class a) {
Class [ ] interfaces1 = a. getInterfaces ( ) ;
if ( interfaces1. length <= 0 ) {
System . out. println ( a. getName ( ) ) ;
return ;
}
System . out. println ( a. getName ( ) ) ;
Class aClass = interfaces1[ 0 ] ;
getkeyInterface ( aClass) ;
}
}
package com. mvc. framework. servlet ;
public class b implements c{
}
package com. mvc. framework. servlet ;
public interface c extends d{
}
package com. mvc. framework. servlet ;
public interface d {
}
package com. mvc. framework. servlet ;
public interface f extends g{
}
package com. mvc. framework. servlet ;
public interface g {
}
dependObject = map. get ( value+ declaredField. getType ( ) . getName ( ) ) ;
package com. mvc. framework. util ;
import java. util. Map ;
public class UtilGetClassInterfaces {
public static void getkeyClass ( String beanName, Class a, Map map, Object o) {
Class superclass = a. getSuperclass ( ) ;
if ( "java.lang.Object" . equals ( superclass. getName ( ) ) ) {
map. put ( beanName + a. getName ( ) , o) ;
} else {
map. put ( beanName + a. getName ( ) , o) ;
getkeyClass ( beanName, superclass, map, o) ;
}
Class [ ] interfaces = a. getInterfaces ( ) ;
for ( Class anInterface : interfaces) {
getkeyInterface ( beanName, anInterface, map, o) ;
}
}
private static void getkeyInterface ( String beanName, Class a, Map map, Object o) {
Class [ ] interfaces1 = a. getInterfaces ( ) ;
if ( interfaces1. length <= 0 ) {
map. put ( beanName + a. getName ( ) , o) ;
return ;
}
map. put ( beanName + a. getName ( ) , o) ;
Class aClass = interfaces1[ 0 ] ;
getkeyInterface ( beanName, aClass, map, o) ;
}
}
if ( ju== 1 ) {
UtilGetClassInterfaces . getkeyClass ( beanName, aClass, map, o) ;
} else {
map. put ( beanName, o) ;
}
String requestURI = req. getRequestURI ( ) ;
String contextPath = req. getContextPath ( ) ;
System . out. println ( "项目名称：" + contextPath) ;
String substring = requestURI. substring ( contextPath. length ( ) , requestURI. length ( ) ) ;
System . out. println ( "拿取的路径：" + substring) ;
Method method = handlerMapping. get ( substring) ;
String value = aClass. getAnnotation ( RequestMapping . class ) . value ( ) ;
if ( "/" . equals ( value. substring ( 0 , 1 ) ) == false ) {
value = "/" + value;
}
String value = annotation. value ( ) ;
if ( "/" . equals ( value. substring ( 0 , 1 ) ) == false ) {
value = "/" + value;
}
package com. mvc. framework. servlet ;
import java. lang. reflect. Method ;
public class a {
public void fa ( String a, Integer b) {
System . out. println ( 1 + a + b) ;
}
public void fb ( ) {
System . out. println ( 1 ) ;
}
public static void main ( String [ ] args) {
try {
Class < a> = a. class ;
a a = aClass. newInstance ( ) ;
Method [ ] methods = aClass. getMethods ( ) ;
for ( int i = 0 ; i < methods. length; i++ ) {
System . out. println ( methods[ i] . getName ( ) ) ;
}
Method fa = aClass. getMethod ( "fb" ) ;
fa. invoke ( a) ;
Method fb = aClass. getMethod ( "fa" , String . class , Integer . class ) ;
fb. invoke ( a, "2" , 1 ) ;
} catch ( Exception e) {
e. printStackTrace ( ) ;
}
}
}
package com. mvc. framework. pojo ;
import java. lang. reflect. Method ;
import java. util. HashMap ;
import java. util. Map ;
import java. util. regex. Pattern ;
public class Handler {
private Object controller;
private Method method;
private Pattern pattern;
private Map < String , Integer > ;
public Handler ( Object controller, Method method, Pattern pattern) {
this . controller = controller;
this . method = method;
this . pattern = pattern;
this . paramIndexMapping = new HashMap < > ( ) ;
}
public Object getController ( ) {
return controller;
}
public void setController ( Object controller) {
this . controller = controller;
}
public Method getMethod ( ) {
return method;
}
public void setMethod ( Method method) {
this . method = method;
}
public Pattern getPattern ( ) {
return pattern;
}
public void setPattern ( Pattern pattern) {
this . pattern = pattern;
}
public Map < String , Integer > getParamIndexMapping ( ) {
return paramIndexMapping;
}
public void setParamIndexMapping ( Map < String , Integer > ) {
this . paramIndexMapping = paramIndexMapping;
}
}
private List < Handler > = new ArrayList < > ( ) ;
package com. mvc. framework. servlet ;
import java. util. regex. Matcher ;
import java. util. regex. Pattern ;
public class a {
public static void main ( String [ ] args) {
String a = "[0-9]{3}" ;
String b = "122" ;
CharSequence aa = b;
System . out. println ( b. matches ( a) ) ;
Pattern pattern = Pattern . compile ( "[0-9]{3}" ) ;
Matcher m = pattern. matcher ( "122" ) ;
boolean matches = m. matches ( ) ;
System . out. println ( matches) ;
System . out. println ( pattern) ;
}
}
if ( method. isAnnotationPresent ( RequestMapping . class ) ) {
RequestMapping annotation = method. getAnnotation ( RequestMapping . class ) ;
String value = annotation. value ( ) ;
if ( "/" . equals ( value. substring ( 0 , 1 ) ) == false ) {
value = "/" + value;
}
String url = baseUrl;
url += value;
Handler handler = new Handler ( entry. getValue ( ) , method, Pattern . compile ( url) ) ;
Parameter [ ] parameters = method. getParameters ( ) ;
for ( int i = 0 ; i < parameters. length; i++ ) {
Parameter parameter = parameters[ i] ;
if ( parameter. getType ( ) == HttpServletRequest . class || parameter. getType ( ) == HttpServletResponse . class ) {
handler. getParamIndexMapping ( ) . put ( parameter. getType ( ) . getSimpleName ( ) , i) ;
} else {
handler. getParamIndexMapping ( ) . put ( parameter. getName ( ) , i) ;
}
}
handlerMapping. add ( handler) ;
}
package com. mvc. framework. servlet ;
import java. lang. reflect. Method ;
public class a {
public void fa ( String a, Integer b, int j) {
}
public static void main ( String [ ] args) throws Exception {
Class < a> = a. class ;
Method fa = aClass. getMethod ( "fa" , String . class , Integer . class , int . class ) ;
Class < ? > [ ] parameterTypes = fa. getParameterTypes ( ) ;
for ( int i = 0 ; i < parameterTypes. length; i++ ) {
Class < ? > = parameterTypes[ i] ;
System . out. println ( parameterType. getSimpleName ( ) ) ;
}
}
}
@Override
protected void doPost ( HttpServletRequest req, HttpServletResponse resp) throws ServletException , IOException {
Handler handler = getHandler ( req) ;
if ( handler == null ) {
resp. getWriter ( ) . write ( "404 not found" ) ;
return ;
}
Class < ? > [ ] parameterTypes = handler. getMethod ( ) . getParameterTypes ( ) ;
Object [ ] objects = new Object [ parameterTypes. length] ;
int [ ] ii = new int [ parameterTypes. length] ;
Map < String , String [ ] > parameterMap = req. getParameterMap ( ) ;
Set < Map. Entry < String , String [ ] >> entries = parameterMap. entrySet ( ) ;
for ( Map. Entry < String , String [ ] > param : entries) {
String value = "" ;
for ( int i = 0 ; i < param. getValue ( ) . length; i++ ) {
if ( i >= param. getValue ( ) . length - 1 ) {
value = param. getValue ( ) [ i] ;
continue ;
}
value = param. getValue ( ) [ i] + "," ;
}
if ( ! handler. getParamIndexMapping ( ) . containsKey ( param. getKey ( ) ) ) {
continue ;
}
Integer integer = handler. getParamIndexMapping ( ) . get ( param. getKey ( ) ) ;
if ( "String" . equals ( parameterTypes[ integer] . getSimpleName ( ) ) ) {
objects[ integer] = value;
}
if ( "Integer" . equals ( parameterTypes[ integer] . getSimpleName ( ) ) || "int" . equals ( parameterTypes[ integer] . getSimpleName ( ) ) ) {
value = value. split ( "," ) [ 0 ] ;
Integer i = null ;
try {
i = Integer . parseInt ( value) ;
} catch ( Exception e) {
e. printStackTrace ( ) ;
throw new RuntimeException ( "String转换Integet报错，参数名称是：" + param. getKey ( ) ) ;
}
objects[ integer] = i;
}
ii[ integer] = 1 ;
}
Integer integer = handler. getParamIndexMapping ( ) . get ( HttpServletRequest . class . getSimpleName ( ) ) ;
objects[ integer] = req;
ii[ integer] = 1 ;
integer = handler. getParamIndexMapping ( ) . get ( HttpServletResponse . class . getSimpleName ( ) ) ;
objects[ integer] = resp;
ii[ integer] = 1 ;
for ( int i = 0 ; i < ii. length; i++ ) {
if ( ii[ i] == 0 ) {
if ( "int" . equals ( parameterTypes[ i] . getSimpleName ( ) ) ) {
objects[ i] = 0 ;
}
}
}
try {
handler. getMethod ( ) . invoke ( handler. getController ( ) , objects) ;
} catch ( Exception e) {
e. printStackTrace ( ) ;
}
}
private Handler getHandler ( HttpServletRequest req) {
if ( handlerMapping. isEmpty ( ) ) {
return null ;
}
String requestURI = req. getRequestURI ( ) ;
String contextPath = req. getContextPath ( ) ;
String substring = requestURI. substring ( contextPath. length ( ) , requestURI. length ( ) ) ;
for ( Handler handler : handlerMapping) {
Matcher matcher = handler. getPattern ( ) . matcher ( substring) ;
if ( ! matcher. matches ( ) ) {
continue ;
}
return handler;
}
return null ;
}
package com. mvc. framework. controller ;
import com. mvc. framework. annotations. Autowired ;
import com. mvc. framework. annotations. Controller ;
import com. mvc. framework. annotations. RequestMapping ;
import com. mvc. framework. service. DemoService ;
import javax. servlet. http. HttpServletRequest ;
import javax. servlet. http. HttpServletResponse ;
@Controller
@RequestMapping ( "/demo" )
public class DemoController {
@Autowired
private DemoService demoService;
@RequestMapping ( "/query" )
public String query ( HttpServletRequest request, HttpServletResponse response, String name) {
String s = demoService. get ( name) ;
return s;
}
}
@RequestMapping ( "/query" )
public String query ( HttpServletRequest request, HttpServletResponse response, String name) {
System . out. println ( request) ;
System . out. println ( response) ;
String s = demoService. get ( name) ;
return s;
}
package com. mvc. framework. service. impl ;
import com. mvc. framework. annotations. Service ;
import com. mvc. framework. service. DemoService ;
@Service
public class DemoServiceImpl implements DemoService {
@Override
public String get ( String name) {
System . out. println ( "打印：" + name) ;
return name;
}
}
if ( parameter. getType ( ) == HttpServletRequest . class || parameter. getType ( ) == HttpServletResponse . class ) {
handler. getParamIndexMapping ( ) . put ( parameter. getType ( ) . getSimpleName ( ) , i) ;
} else {
handler. getParamIndexMapping ( ) . put ( parameter. getName ( ) , i) ;
}
package com. mvc. framework. servlet ;
import java. lang. reflect. Method ;
import java. lang. reflect. Parameter ;
public class a {
public void fa ( String nam2, String name1) {
}
public void fb ( String nam2, String name1) {
}
public static void main ( String [ ] args) {
Class < a> = a. class ;
Method [ ] fa = aClass. getMethods ( ) ;
for ( int i = 0 ; i < fa. length; i++ ) {
Method method = fa[ i] ;
System . out. println ( method. getName ( ) ) ;
Parameter [ ] parameters = method. getParameters ( ) ;
for ( int ii = 0 ; ii < parameters. length; ii++ ) {
Parameter parameter = parameters[ ii] ;
System . out. println ( parameter. getName ( ) ) ;
}
}
}
}
- parameters，编译选项
< build> < plugins> < plugin> < groupId> </ groupId> < artifactId> </ artifactId> < version> </ version> < configuration> < source> </ source> < target> </ target> < compilerArguments> < parameters/> </ compilerArguments> </ configuration> </ plugin> </ plugins> </ build> spring是使用字节码分析库（如 ASM）来动态分析类文件，而不依赖于编译器生成的字节码，这种技术使 Spring 能够获取参数名称，因为他是直接分析文件的，也就可以说，他内部的代码是相当于跳过了操作了-parameters选项，而访问并处理字节码文件（实际上再怎么处理字节码文件中都会保留原始参数名称，否则的话，也不可能使用该名称的变量了，他只是不让你直接获取即可，那么如果说选项中他-parameters是解决某一个开关导致的不让获取，那么spring是直接从文件找，也自然就跳过了这个开关）
public class ceshi {
public static void main ( String [ ] args) {
for ( String arg : args) {
System . out. println ( arg) ;
}
}
}
< dependency> < groupId> </ groupId> < artifactId> </ artifactId> < version> </ version> </ dependency> < build> < plugins> < plugin> < groupId> </ groupId> < artifactId> </ artifactId> < version> </ version> < configuration> < source> </ source> < target> </ target> < compilerArguments> < parameters/> </ compilerArguments> </ configuration> </ plugin> </ plugins> </ build> package com. mvc. framework. servlet ;
import java. lang. reflect. Method ;
import java. lang. reflect. Parameter ;
public class a {
public void fa ( String nam2, String name1) {
}
public void fb ( String nam2, String name1) {
}
public static void main ( String [ ] args) {
Class < a> = a. class ;
Method [ ] fa = aClass. getMethods ( ) ;
for ( int i = 0 ; i < fa. length; i++ ) {
Method method = fa[ i] ;
System . out. println ( method. getName ( ) ) ;
Parameter [ ] parameters = method. getParameters ( ) ;
for ( int ii = 0 ; ii < parameters. length; ii++ ) {
Parameter parameter = parameters[ ii] ;
System . out. println ( parameter. getName ( ) ) ;
}
}
}
}
package com. mvc. framework. config ;
import org. objectweb. asm. ClassVisitor ;
import org. objectweb. asm. Label ;
import org. objectweb. asm. MethodVisitor ;
import org. objectweb. asm. Opcodes ;
import java. util. HashMap ;
import java. util. Map ;
public class ParameterNameVisitor extends ClassVisitor {
private String methodName;
private Map map;
public ParameterNameVisitor ( String methodName) {
super ( Opcodes . ASM7 ) ;
this . methodName = methodName;
}
@Override
public MethodVisitor visitMethod ( int access, String name, String descriptor, String signature, String [ ] exceptions) {
if ( name. equals ( methodName) ) {
return new MethodParameterVisitor ( ) ;
}
return null ;
}
public Map getParameterNames ( ) {
return map;
}
class MethodParameterVisitor extends MethodVisitor {
public MethodParameterVisitor ( ) {
super ( Opcodes . ASM7 ) ;
}
@Override
public void visitLocalVariable ( String name, String descriptor, String signature, Label start, Label end, int index) {
if ( index >= 0 ) {
if ( map == null ) {
map = new HashMap < > ( ) ;
}
map. put ( index - 1 , name) ;
}
}
}
}
package com. mvc. framework. config ;
import org. objectweb. asm. * ;
import java. util. Map ;
public class ParameterNameExtractor {
public static Map getParameterNames ( String className, String methodName) throws Exception {
ClassReader reader = new ClassReader ( className) ;
ParameterNameVisitor visitor = new ParameterNameVisitor ( methodName) ;
reader. accept ( visitor, 0 ) ;
return visitor. getParameterNames ( ) ;
}
}
package com. mvc. framework. servlet ;
import com. mvc. framework. config. ParameterNameExtractor ;
import java. util. Map ;
public class a {
String name;
public a ( String name) {
this . name = name;
}
public a ( String name, String j) {
this . name = name;
}
public void fa ( String nam2, String name1) {
}
public void fb ( String nam2, String name1) {
}
public static void main ( String [ ] args) throws Exception {
String className = "com.mvc.framework.servlet.a" ;
String methodName = "fa" ;
Map map = ParameterNameExtractor . getParameterNames ( className, methodName) ;
for ( int i = 0 ; i < map. size ( ) ; i++ ) {
System . out. println ( "参数列表的位置：" + i + "，名称是: " + map. get ( i) ) ;
}
methodName = "fb" ;
map = ParameterNameExtractor . getParameterNames ( className, methodName) ;
for ( int i = 0 ; i < map. size ( ) ; i++ ) {
System . out. println ( "参数列表的位置：" + i + "，名称是: " + map. get ( i) ) ;
}
}
}
Map < String , String > = null ;
try {
prmap = ParameterNameExtractor . getParameterNames ( aClass. getName ( ) , method. getName ( ) ) ;
} catch ( Exception e) {
e. printStackTrace ( ) ;
}
Parameter [ ] parameters = method. getParameters ( ) ;
for ( int i = 0 ; i < parameters. length; i++ ) {
Parameter parameter = parameters[ i] ;
if ( parameter. getType ( ) == HttpServletRequest . class || parameter. getType ( ) == HttpServletResponse . class ) {
handler. getParamIndexMapping ( ) . put ( parameter. getType ( ) . getSimpleName ( ) , i) ;
} else {
handler. getParamIndexMapping ( ) . put ( prmap. get ( i) , i) ;
}
}
handlerMapping. add ( handler) ;
package com. mvc. framework. servlet ;
import com. mvc. framework. config. ParameterNameExtractor ;
import java. util. Map ;
public class a {
public static void main ( String [ ] args) throws Exception {
String className = "com.mvc.framework.controller.DemoController" ;
String methodName = "query" ;
Map map = ParameterNameExtractor . getParameterNames ( className, methodName) ;
for ( int i = 0 ; i < map. size ( ) ; i++ ) {
System . out. println ( "参数列表的位置：" + i + "，名称是: " + map. get ( i) ) ;
}
}
}
@Override
public void init ( ServletConfig config) {
String className = "com.mvc.framework.controller.DemoController" ;
String methodName = "query" ;
Map map = ParameterNameExtractor . getParameterNames ( className, methodName) ;
for ( int i = 0 ; i < map. size ( ) ; i++ ) {
System . out. println ( "参数列表的位置：" + i + "，名称是: " + map. get ( i) ) ;
}
}
public ClassReader ( String className) throws IOException {
this ( readStream ( ClassLoader . getSystemResourceAsStream ( className. replace ( '.' , '/' ) + ".class" ) , true ) ) ;
}
private static byte [ ] readStream ( InputStream inputStream, boolean close) throws IOException {
if ( inputStream == null ) {
throw new IOException ( "Class not found" ) ;
} else {
. . .
private void initHandlerMapping ( ServletConfig config) {
String ba = aClass. getName ( ) . replace ( '.' , '/' ) + ".class" ;
prmap = ParameterNameExtractor . getParameterNames ( config. getServletContext ( ) . getRealPath ( "/" ) + "WEB-INF\\classes\\" + ba, method. getName ( ) ) ;
InputStream inputStream = new FileInputStream ( className) ;
ClassReader reader = new ClassReader ( inputStream) ;
