SpringBoot配置自定義攔截器實現過程詳解

package net.lesscoding.interceptor;
import javax.servlet.ReadListener;
import javax.servlet.ServletInputStream;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletRequestWrapper;
import java.io.*;
/**
 *  由於流隻能讀取一次，所以使用此包裝類對HttpServletRequest對象進行包裝，讀取完之後再將
 *  內容塞回去，不影響後續springmvc的參數處理。
 */
public class RequestWrapper extends HttpServletRequestWrapper {
    private String body;
    public RequestWrapper(HttpServletRequest request) {
        super(request);
        if (request.getHeader("Content-Type") != null
                && request.getHeader("Content-Type").contains("multipart/form-data")){
            try{
                request.getParts();
            }catch (Exception e){
                e.printStackTrace();
            }
        }
        StringBuilder stringBuilder = new StringBuilder();
        try (InputStream inputStream = request.getInputStream();
             BufferedReader bufferedReader = new BufferedReader(new InputStreamReader(inputStream))){
            char[] charBuffer = new char[128];
            int bytesRead = -1;
            while ((bytesRead = bufferedReader.read(charBuffer)) > 0) {
                stringBuilder.append(charBuffer, 0, bytesRead);
            }
        }catch (NullPointerException ex){
            stringBuilder.append("");
        } catch (Exception ex) {
        }
        body = stringBuilder.toString();
    }
    @Override
    public ServletInputStream getInputStream() throws IOException {
        final ByteArrayInputStream byteArrayInputStream = new ByteArrayInputStream(body.getBytes());
        ServletInputStream servletInputStream = new ServletInputStream() {
            @Override
            public boolean isFinished() {
                return false;
            }
            @Override
            public boolean isReady() {
                return false;
            }
            @Override
            public void setReadListener(ReadListener readListener) {
            }
            @Override
            public int read() throws IOException {
                return byteArrayInputStream.read();
            }
        };
        return servletInputStream;

    }
    @Override
    public BufferedReader getReader() throws IOException {
        return new BufferedReader(new InputStreamReader(this.getInputStream()));
    }
    public String getBody() {
        return body;
    }
    public void setBody(String body) {
        this.body = body;
    }
}

package net.lesscoding.filter;
import net.lesscoding.interceptor.RequestWrapper;
import javax.servlet.*;
import javax.servlet.http.HttpServletRequest;
import java.io.IOException;
/**
 * @apiNote 傳遞request的過濾器
 */
public class RepeatedlyReadFilter implements Filter {
    @Override
    public void init(FilterConfig filterConfig) throws ServletException {
    }
    @Override
    public void doFilter(ServletRequest request, ServletResponse response, FilterChain chain) throws IOException, ServletException {
        ServletRequest requestWrapper = null;
        if(request instanceof HttpServletRequest){
            requestWrapper = new RequestWrapper((HttpServletRequest) request);
        }
        chain.doFilter( requestWrapper == null ? request : requestWrapper,response );
    }
    @Override
    public void destroy() {
    }
}

package net.lesscoding.interceptor;
import cn.hutool.core.util.StrUtil;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.context.annotation.Configuration;
import org.springframework.data.redis.core.RedisTemplate;
import org.springframework.web.servlet.HandlerInterceptor;
import org.springframework.web.servlet.ModelAndView;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
import java.util.concurrent.TimeUnit;
/**
 * @apiNote 登錄攔截器
 */
@Configuration
public class LoginInterceptor implements HandlerInterceptor {
    @Autowired
    private RedisTemplate redisTemplate;
    @Override
    public boolean preHandle(HttpServletRequest request, HttpServletResponse response, Object handler) throws Exception {
        String token = request.getHeader("AccessToken");
        String redisToken = String.valueOf(redisTemplate.opsForValue().get(token));
        if(StrUtil.isBlank(redisToken)){
            throw new RuntimeException("token失效,請重新登錄");
        }
        // 這裡為瞭方便 成功之後就刷新在redis中的時間
        redisTemplate.opsForValue().set("token",redisToken,30, TimeUnit.MINUTES);
        return true;
    }
    @Override
    public void postHandle(HttpServletRequest request, HttpServletResponse response, Object handler, ModelAndView modelAndView) throws Exception {
    }
    @Override
    public void afterCompletion(HttpServletRequest request, HttpServletResponse response, Object handler, Exception ex) throws Exception {
    }
}

package net.lesscoding.config;
import lombok.extern.slf4j.Slf4j;
import net.lesscoding.common.Result;
import net.lesscoding.common.ResultFactory;
import org.springframework.web.bind.annotation.ExceptionHandler;
import org.springframework.web.bind.annotation.RestControllerAdvice;
/**
 * @apiNote 全局異常處理器
 */
@RestControllerAdvice
@Slf4j
public class GlobalExceptionHandler {
    @ExceptionHandler(value = RuntimeException.class)
    public Result runtimeExceptionHandler(RuntimeException e){
        e.printStackTrace();
        log.error("{}", e.getMessage());
        return ResultFactory.buildThrowable(e);
    }
    @ExceptionHandler(value = Exception.class)
    public Result exceptionHandler(Exception e){
        e.printStackTrace();
        log.error("{}", e.getMessage());
        return ResultFactory.buildThrowable(e);
    }
    @ExceptionHandler(value = Throwable.class)
    public Result exceptionHandler(Throwable t){
        t.printStackTrace();
        log.error("{}", t.getMessage());
        return ResultFactory.buildThrowable(t);
    }
}

package net.lesscoding.config;
import net.lesscoding.filter.RepeatedlyReadFilter;
import net.lesscoding.interceptor.LoginInterceptor;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.boot.web.servlet.FilterRegistrationBean;
import org.springframework.context.annotation.Bean;
import org.springframework.context.annotation.Configuration;
import org.springframework.web.servlet.config.annotation.InterceptorRegistry;
import org.springframework.web.servlet.config.annotation.WebMvcConfigurer;
/**
 * @apiNote 對項目進行配置攔截器
 */
@Configuration
public class LoginConfiguration implements WebMvcConfigurer {
    @Autowired
    private LoginInterceptor loginInterceptor;
    @Bean
    public FilterRegistrationBean repeatedlyReadFilter(){
        FilterRegistrationBean registration = new FilterRegistrationBean();
        RepeatedlyReadFilter repeatedlyReadFilter = new RepeatedlyReadFilter();
        registration.setFilter(repeatedlyReadFilter);
        registration.addUrlPatterns("/*");
        return registration;
    }
    @Override
    public void addInterceptors(InterceptorRegistry registry) {
        registry.addInterceptor(loginInterceptor)
                // 攔截所有請求
                .addPathPatterns("/**")
                // 排除登錄註冊修改密碼等接口
                .excludePathPatterns("/oauth/**","/login/**","logout/**","/common/**", "options","/try/**","/user/updatePwd")
                // 判處swagger等接口
                .excludePathPatterns("/doc.html","/swagger-resources/**", "/webjars/**", "/v2/**", "/swagger-ui.html/**","/favicon.ico")
        ;
    }
}