Question

根据this answer我尝试编写代码：

POJO：

class MyBean{

    public String getValueName() {
        return valueName;
    }

    public void setValueName(String valueName) {
        this.valueName = valueName;
    }

    String valueName;
}

控制器内部：

    @ModelAttribute
    public MyBean createMyBean() {
        return new MyBean();
    }
    @RequestMapping(value = "/getMyBean", method = RequestMethod.GET)
    public String getMyBean(@ModelAttribute MyBean myBean) {
        System.out.println(myBean.getValueName());
        return "pathToJsp";
    }

web.xml配置：

<filter>
    <filter-name>caseInsensitiveFilter</filter-name>
    <filter-class>com.terminal.interceptor.CaseInsensitiveRequestFilter</filter-class>
</filter>

<filter-mapping>
    <filter-name>caseInsensitiveFilter</filter-name>
    <url-pattern>/*</url-pattern>
</filter-mapping>

过滤器：

@Component
public class CaseInsensitiveRequestFilter extends OncePerRequestFilter {
    @Override
    protected void doFilterInternal(HttpServletRequest request, HttpServletResponse response, FilterChain filterChain) throws ServletException, IOException {
        filterChain.doFilter(new CaseInsensitiveHttpServletRequestWrapper(request), response);
    }

    private static class CaseInsensitiveHttpServletRequestWrapper extends HttpServletRequestWrapper {

        private final LinkedCaseInsensitiveMap params = new LinkedCaseInsensitiveMap();

        /**
         * Constructs a request object wrapping the given request.
         *
         * @param request
         * @throws IllegalArgumentException if the request is null
         */
        private CaseInsensitiveHttpServletRequestWrapper(HttpServletRequest request) {
            super(request);
            params.putAll(request.getParameterMap());
        }

        @Override
        public String getParameter(String name) {
            String[] values = getParameterValues(name);
            if (values == null || values.length == 0) {
                return null;
            }
            return values[0];
        }

        @Override
        public Map getParameterMap() {
            return Collections.unmodifiableMap(this.params);
        }

        @Override
        public Enumeration getParameterNames() {
            return Collections.enumeration(this.params.keySet());
        }

        @Override
        public String[] getParameterValues(String name) {
            return (String[]) params.get(name);
        }
    }
}

在调试中我看到调用过滤器方法但我无法实现case insentive get parameters mapping。

例如localhost:8081/getMyBean?valueName=trololo有效但localhost:8081/getMyBean?valuename=trololo - 不是

Answer 1

我相信你的问题是public static void main (String[]args) { ArrayList<Integer> answers = new ArrayList<Integer>(); int temp = 0; int result = 0; for (int i = 100; i <= 999; i++){ for (int z = 100; z <= 999; z++){ int prod = i * z; result = pal(prod); answers.add(result); } } int answer = Collections.max(answers); System.out.println(answer); } public static int pal(int n){ int palindrome; //You could place it here. String temp2 = String.valueOf(n); for (int i = 0; i < temp2.length()/2; i++){ if (temp2.charAt(i) != temp2.charAt(temp2.length()-1-i)) { palindrome = Integer.parseInt(temp2); return palindrome; } } return palindrome; } }。您要求Spring将参数映射到@ModelAttribute对象，并且此对象内的属性为MyBean。

为了让Spring将params反映到对象中，它需要处于正确的情况。

您有两个选择：

将MyBean对象中的属性名称更改为valueName，将所有属性名称更改为小写，它应该在您的解决方案的帮助下工作。
删除valuename并为每个属性添加@ModelAttribute。如果你有很多道具，这可能会很痛苦。

Answer 2

实际上，您必须根据bean变量名更改CaseInsensitiveRequestFilter类中的内容。在您的情况下，变量是valueName，因此对于每个请求，它将根据您的变量setter方法驼峰案例注入转换它，然后根据您的请求进行匹配。只需尝试自定义要求：

package biz.deinum.web.filter;

import java.io.IOException;
import java.util.Collections;
import java.util.Enumeration;
import java.util.HashMap;
import java.util.Iterator;
import java.util.Map;
import java.util.Map.Entry;
import java.util.Set;

import javax.servlet.FilterChain;
import javax.servlet.ServletException;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletRequestWrapper;
import javax.servlet.http.HttpServletResponse;

import org.springframework.util.LinkedCaseInsensitiveMap;
import org.springframework.web.filter.OncePerRequestFilter;

public class CaseInsensitiveRequestFilter extends OncePerRequestFilter {
    @Override
    protected void doFilterInternal(HttpServletRequest request, HttpServletResponse response, FilterChain filterChain) throws ServletException, IOException {
        filterChain.doFilter(new CaseInsensitiveHttpServletRequestWrapper(request), response);
    }

    private static class CaseInsensitiveHttpServletRequestWrapper extends HttpServletRequestWrapper {

        private final LinkedCaseInsensitiveMap<String[]> params = new LinkedCaseInsensitiveMap<>();

        private CaseInsensitiveHttpServletRequestWrapper(HttpServletRequest request) {
            super(request);
            Map<String, String[]> map = request.getParameterMap();
            Set set = map.entrySet();
            Iterator it = set.iterator();
            Map<String, String[]> tempMap = new HashMap<String, String[]>(); 
            while (it.hasNext()) {
                Map.Entry<String, String[]> entry = (Entry<String, String[]>) it.next();
                String key = entry.getKey();
                // Keep your parameter bean name here in your case it is "valueName"
                String beanParamaterName = "valueName";
                if(key.equalsIgnoreCase(beanParamaterName)){
                    tempMap.put(key.toLowerCase(), entry.getValue());
                }
            }
            params.putAll(tempMap);
        }

        @Override
        public String getParameter(String name) {
            String[] values = getParameterValues(name);
            System.out.println(values.toString()+"-");
            if (values == null || values.length == 0) {
                return null;
            }
            return values[0];
        }

        @Override
        public Map<String, String[]> getParameterMap() {
            return Collections.unmodifiableMap(this.params);
        }

        @Override
        public Enumeration<String> getParameterNames() {
            return Collections.enumeration(this.params.keySet());
        }

        @Override
        public String[] getParameterValues(String name) {
            System.out.println(name);
            return (String[])params.get(name);
        }
    }
}

春天的mvc。不区分大小写的get参数映射

2 个答案: