前端传输数据到后台对参数进行去除空格处理

前端传输数据到后台对参数进行去除空格处理：
参考文章忘记出自哪里了，记录一下方便自己以后查看

import javax.servlet.*;
import javax.servlet.http.HttpServletRequest;
import java.io.IOException;

/**
 * Repeatable 过滤器
 */
public class ParamsFilter implements Filter {

    @Override
    public void doFilter(ServletRequest arg0, ServletResponse arg1, FilterChain arg2) throws IOException, ServletException {
        ParameterRequestWrapper parmsRequest = new ParameterRequestWrapper((HttpServletRequest)arg0);
        arg2.doFilter(parmsRequest, arg1);
    }

    @Override
    public void init(FilterConfig arg0) throws ServletException {

    }

    @Override
    public void destroy() {

    }

}

import org.springframework.boot.web.servlet.FilterRegistrationBean;
import org.springframework.context.annotation.Bean;
import org.springframework.context.annotation.Configuration;

import javax.servlet.DispatcherType;

@Configuration
public class FilterRegistre {


    @Bean
    public FilterRegistrationBean parmsFilterRegistration() {
        FilterRegistrationBean registration = new FilterRegistrationBean();
        registration.setDispatcherTypes(DispatcherType.REQUEST);
        registration.setFilter(new ParamsFilter());
        registration.addUrlPatterns("/*");
        registration.setName("paramsFilter");
        registration.setOrder(Integer.MAX_VALUE - 1);
        return registration;
    }
}

import com.alibaba.fastjson.JSON;
import org.apache.commons.io.IOUtils;
import org.springframework.http.HttpHeaders;
import org.springframework.http.MediaType;
import org.springframework.util.StringUtils;

import javax.servlet.ReadListener;
import javax.servlet.ServletInputStream;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletRequestWrapper;
import java.io.ByteArrayInputStream;
import java.io.IOException;
import java.util.HashMap;
import java.util.Iterator;
import java.util.Map;
import java.util.Set;

/**
 * 过滤请求参数前后空格
 *
 */
public class ParameterRequestWrapper extends HttpServletRequestWrapper {

    private Map<String, String[]> params = new HashMap<String, String[]>();

    public ParameterRequestWrapper(HttpServletRequest request) {
        // 将request交给父类，以便于调用对应方法的时候，将其输出，其实父亲类的实现方式和第一种new的方式类似
        super(request);
        //将参数表，赋予给当前的Map以便于持有request中的参数
        Map<String, String[]> requestMap = request.getParameterMap();
        //System.out.println("转化前参数：" + JSON.toJSONString(requestMap));
        this.params.putAll(requestMap);
        this.modifyParameterValues();
        //System.out.println("转化后参数：" + JSON.toJSONString(params));
    }

    /**
     * 重写getInputStream方法  post类型的请求参数必须通过流才能获取到值
     */
    @Override
    public ServletInputStream getInputStream() throws IOException {
        //非json类型，直接返回
        if (!super.getHeader(HttpHeaders.CONTENT_TYPE).equalsIgnoreCase(MediaType.APPLICATION_JSON_VALUE)) {
            return super.getInputStream();
        }
        //为空，直接返回
        String json = IOUtils.toString(super.getInputStream(), "utf-8");
        if (StringUtils.isEmpty(json)) {
            return super.getInputStream();
        }

       /*
        * 只拦截 map 类型json数据，对于数组类型json数据放行
    */
        final char[] strChar = json.substring(0, 1).toCharArray();
        final char firstChar = strChar[0];
        if(firstChar == '{'){
            Map<String, Object> map = (Map<String, Object>) JSON.parse(json);
            map.forEach((key,value)->{
                System.out.println(key+":"+value);
                if (value instanceof String){
                    value=((String) value).trim();
                    map.put(key, value);
                }
            });

            ByteArrayInputStream bis = new ByteArrayInputStream(JSON.toJSONString(map).getBytes("utf-8"));
            return new MyServletInputStream(bis);
        }else {
            ByteArrayInputStream bis = new ByteArrayInputStream(json.getBytes("utf-8"));
            return new MyServletInputStream(bis);
        }

}

    /**
     * 将parameter的值去除空格后重写回去
     */
    public void modifyParameterValues() {
        Set<String> set = params.keySet();
        Iterator<String> it = set.iterator();
        while (it.hasNext()) {
            String key = (String) it.next();
            String[] values = params.get(key);
            values[0] = values[0].trim();
            params.put(key, values);
        }
    }

    /**
     * 重写getParameter 参数从当前类中的map获取
     */
    @Override
    public String getParameter(String name) {
        String[] values = params.get(name);
        if (values == null || values.length == 0) {
            return null;
        }
        return values[0];
    }

    /**
     * 重写getParameterValues
     */
    public String[] getParameterValues(String name) {//同上
        return params.get(name);
    }

    class MyServletInputStream extends ServletInputStream {
        private ByteArrayInputStream bis;

        public MyServletInputStream(ByteArrayInputStream bis) {
            this.bis = bis;
        }

        @Override
        public boolean isFinished() {
            return true;
        }

        @Override
        public boolean isReady() {
            return true;
        }

        @Override
        public void setReadListener(ReadListener listener) {

        }

        @Override
        public int read() throws IOException {
            return bis.read();
        }
    }

}