ServletUtils工具类

import com.zcys.admin.common.responses.Response;
import lombok.extern.slf4j.Slf4j;
import org.springframework.http.MediaType;
import org.springframework.web.context.request.RequestAttributes;
import org.springframework.web.context.request.RequestContextHolder;
import org.springframework.web.context.request.ServletRequestAttributes;

import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
import javax.servlet.http.HttpSession;
import java.io.PrintWriter;
import java.io.UnsupportedEncodingException;
import java.net.URLDecoder;
import java.net.URLEncoder;
import java.nio.charset.StandardCharsets;
import java.util.Objects;

/**
 * 客户端响应工具类
 */
@Slf4j
public class ServletUtils {

    /**
     * 获取String参数
     */
    public static String getParameter(String name) {
        return getRequest().getParameter(name);
    }

    /**
     * 获取String参数
     */
    public static String getHeader(String name) {
        return getRequest().getHeader(name);
    }

    /**
     * 获取String参数
     */
    public static String getParameter(String name, String defaultValue) {
        return ConvertUtils.toStr(getRequest().getParameter(name), defaultValue);
    }

    /**
     * 获取Integer参数
     */
    public static Integer getParameterToInt(String name) {
        return ConvertUtils.toInt(getRequest().getParameter(name));
    }

    /**
     * 获取Integer参数
     */
    public static Integer getParameterToInt(String name, Integer defaultValue) {
        return ConvertUtils.toInt(getRequest().getParameter(name), defaultValue);
    }

    /**
     * 获取Boolean参数
     */
    public static Boolean getParameterToBool(String name) {
        return ConvertUtils.toBool(getRequest().getParameter(name));
    }

    /**
     * 获取Boolean参数
     */
    public static Boolean getParameterToBool(String name, Boolean defaultValue) {
        return ConvertUtils.toBool(getRequest().getParameter(name), defaultValue);
    }

    /**
     * 获取request
     */
    public static HttpServletRequest getRequest() {
        return getRequestAttributes().getRequest();
    }

    /**
     * 获取response
     */
    public static HttpServletResponse getResponse() {
        return getRequestAttributes().getResponse();
    }

    /**
     * 获取session
     */
    public static HttpSession getSession() {
        return getRequest().getSession();
    }

    public static ServletRequestAttributes getRequestAttributes() {
        RequestAttributes attributes = RequestContextHolder.getRequestAttributes();
        return (ServletRequestAttributes) attributes;
    }

    /**
     * 将字符串渲染到客户端
     *
     * @param response 渲染对象
     * @param failed   响应消息
     */
    public static void responseJson(HttpServletResponse response, Response<String> failed) {
        if (Objects.isNull(failed)) {
            return;
        }

        response.setCharacterEncoding(StandardCharsets.UTF_8.name());
        response.setContentType(MediaType.APPLICATION_JSON_VALUE);

        try (PrintWriter writer = response.getWriter()) {
            String json = JSONUtils.serialize(failed);
            writer.write(json);
            writer.flush();
        } catch (Exception e) {
            log.info("响应失败：", e);
        }
    }

    /**
     * 内容编码
     *
     * @param str 内容
     * @return 编码后的内容
     */
    public static String urlEncode(String str) {
        try {
            return URLEncoder.encode(str, StandardCharsets.UTF_8.name());
        } catch (UnsupportedEncodingException e) {
            log.info("内容编码失败：", e);
            return StringUtils.EMPTY;
        }
    }

    /**
     * 内容解码
     *
     * @param str 内容
     * @return 解码后的内容
     */
    public static String urlDecode(String str) {
        try {
            return URLDecoder.decode(str, StandardCharsets.UTF_8.name());
        } catch (UnsupportedEncodingException e) {
            log.info("内容解码失败：", e);
            return StringUtils.EMPTY;
        }
    }

}