分类： Java
2022-08-19 14:27:13
public class DispatcherServlet extends HttpServlet {
private Map mapping = new HashMap();
@Override
protected void doGet(HttpServletRequest req, HttpServletResponse resp) throws ServletException, IOException {this.doPost(req,resp);}
@Override
protected void doPost(HttpServletRequest req, HttpServletResponse resp) throws ServletException, IOException {
try {
doDispatch(req,resp);
} catch (Exception e) {
resp.getWriter().write("500 Exception " + Arrays.toString(e.getStackTrace()));
}
}
private void doDispatch(HttpServletRequest req, HttpServletResponse resp) throws Exception {
String url = req.getRequestURI();
String contextPath = req.getContextPath();
url = url.replace(contextPath, "").replaceAll("/+", "/");
if(!this.mapping.containsKey(url)){resp.getWriter().write("404 Not Found!!");return;}
Method method = (Method) this.mapping.get(url);
Map params = req.getParameterMap();
method.invoke(this.mapping.get(method.getDeclaringClass().getName()),new Object[]{req,resp,params.get("name")[0]});
}
//当我晕车的时候，我就不去看源码了
//init方法肯定干得的初始化的工作
//inti首先我得初始化所有的相关的类，IOC容器、servletBean
@Override
public void init(ServletConfig config) throws ServletException {
InputStream is = null;
try{
Properties configContext = new Properties();
is = this.getClass().getClassLoader().getResourceAsStream(config.getInitParameter("contextConfigLocation"));
configContext.load(is);
String scanPackage = configContext.getProperty("scanPackage");
doScanner(scanPackage);
for (String className : mapping.keySet()) {
if(!className.contains(".")){continue;}
Class clazz = Class.forName(className);
if(clazz.isAnnotationPresent(Controller.class)){
mapping.put(className,clazz.newInstance());
String baseUrl = "";
if (clazz.isAnnotationPresent(RequestMapping.class)) {
RequestMapping requestMapping = clazz.getAnnotation(RequestMapping.class);
baseUrl = requestMapping.value();
}
Method[] methods = clazz.getMethods();
for (Method method : methods) {
if (!method.isAnnotationPresent(RequestMapping.class)) { continue; }
RequestMapping requestMapping = method.getAnnotation(RequestMapping.class);
String url =跟单网gendan5.com (baseUrl + "/" + requestMapping.value()).replaceAll("/+", "/");
mapping.put(url, method);
System.out.println("Mapped " + url + "," + method);
}
}else if(clazz.isAnnotationPresent(Service.class)){
Service service = clazz.getAnnotation(Service.class);
String beanName = service.value();
if("".equals(beanName)){beanName = clazz.getName();}
Object instance = clazz.newInstance();
mapping.put(beanName,instance);
for (Class i : clazz.getInterfaces()) {
mapping.put(i.getName(),instance);
}
}else {continue;}
}
for (Object object : mapping.values()) {
if(object == null){continue;}
Class clazz = object.getClass();
if(clazz.isAnnotationPresent(Controller.class)){
Field [] fields = clazz.getDeclaredFields();
for (Field field : fields) {
if(!field.isAnnotationPresent(Autowired.class)){continue; }
Autowired autowired = field.getAnnotation(Autowired.class);
String beanName = autowired.value();
if("".equals(beanName)){beanName = field.getType().getName();}
field.setAccessible(true);
try {
field.set(mapping.get(clazz.getName()),mapping.get(beanName));
} catch (IllegalAccessException e) {
e.printStackTrace();
}
}
}
}
} catch (Exception e) {
}finally {
if(is != null){
try {is.close();} catch (IOException e) {
e.printStackTrace();
}
}
}
System.out.print("MVC Framework is init");
}
private void doScanner(String scanPackage) {
URL url = this.getClass().getClassLoader().getResource("/" + scanPackage.replaceAll("\\.","/"));
File classDir = new File(url.getFile());
for (File file : classDir.listFiles()) {
if(file.isDirectory()){ doScanner(scanPackage + "." + file.getName());}else {
if(!file.getName().endsWith(".class")){continue;}
String clazzName = (scanPackage + "." + file.getName().replace(".class",""));
mapping.put(clazzName,null);
}
}
}
}
