使用SpringBoot使用过滤器去除@RequestBody参数两端的空格
使用SpringBoot使用过滤器去除@RequestBody参数两端的空格；一般我们去普通的请求我们都会对请求参数进行验证。Java也提供了@notNull和@notBlank这种验证方式，但是对@RequestBody 这种只能验证是不是非空，对数据两端的空格未进行处理，同时大家也不想遍历一遍参数然后再处理再封装到对象中，正好项目中有这个需要，所以就参考别的做了Post请求中针对application/json格式的有@RequestBody注解的参数进行了去空格处理
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第一步：编写一个配置信息
ParamsFilterConfig.java
package com.codepeople.framework.config;
import javax.servlet.DispatcherType;
import org.springframework.boot.web.servlet.FilterRegistrationBean;
import org.springframework.context.annotation.Bean;
import org.springframework.context.annotation.Configuration;
import com.ruoyi.framework.filter.ParamsFilter;
/**
* @ClassName: ParamsFilterConfig
* @Description: SpringBoot中去除@RequestBody中前后端空格
* @Author 刘 仁
* @DateTime 2020-7-23 10:07:02
*/
@Configuration
public class ParamsFilterConfig {
@Bean
public FilterRegistrationBean paramsFilterRegistration() {
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;
}
}
第二步：编写ParamsFilter过滤器
ParamsFilter.java
package com.kelan.framework.filter;
/**
* @ClassName: ParamsFilter
* @Description:
* @Author 刘 仁
* @DateTime 2021-4-9 10:49:46
*/
import java.io.IOException;
import javax.servlet.DispatcherType;
import javax.servlet.Filter;
import javax.servlet.FilterChain;
import javax.servlet.FilterConfig;
import javax.servlet.ServletException;
import javax.servlet.ServletRequest;
import javax.servlet.ServletResponse;
import javax.servlet.annotation.WebFilter;
import javax.servlet.http.HttpServletRequest;
import org.springframework.core.annotation.Order;
import org.springframework.stereotype.Component;
@Component
@WebFilter(urlPatterns = "/**", filterName = "ParamsFilter", dispatcherTypes = DispatcherType.REQUEST)
@Order(value = 1)
public class ParamsFilter implements Filter {
@Override
public void doFilter(ServletRequest request, ServletResponse response, FilterChain chain)
throws IOException, ServletException {
ParameterRequestWrapper parmsRequest = new ParameterRequestWrapper((HttpServletRequest) request);
chain.doFilter(parmsRequest, response);
}
@Override
public void init(FilterConfig filterConfig) throws ServletException {
}
@Override
public void destroy() {
}
}
第三步：实现ParameterRequestWrapper
ParameterRequestWrapper.java
package com.codepeople.framework.filter;
import java.io.ByteArrayInputStream;
import java.io.IOException;
import java.util.HashMap;
import java.util.Iterator;
import java.util.Map;
import java.util.Set;
import javax.servlet.ReadListener;
import javax.servlet.ServletInputStream;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletRequestWrapper;
import org.apache.commons.io.IOUtils;
import org.apache.commons.lang3.StringUtils;
import org.springframework.http.HttpHeaders;
import org.springframework.http.MediaType;
import com.alibaba.fastjson.JSON;
import com.codepeople.framework.util.StringJsonUtils;
public class ParameterRequestWrapper extends HttpServletRequestWrapper {
private Map<String , String[]> params = new HashMap<>();
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();
this.params.putAll(requestMap);
this.modifyParameterValues();
}
/**
* 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();
}
System.out.println("去除POST请求数据两端的空格前参数："+json);
Map<String,Object> map= StringJsonUtils.jsonStringToMap(json);
System.out.println("去除POST请求数据两端的空格后参数："+JSON.toJSONString(map));
ByteArrayInputStream bis = new ByteArrayInputStream(JSON.toJSONString(map).getBytes("utf-8"));
return new MyServletInputStream(bis);
}
/**
* @Title: modifyParameterValues
* @Description: 将parameter的值去除空格后重写回去
* @DateTime 2020-7-23 10:31:12
*/
public void modifyParameterValues(){
Set<String> set = params.keySet();
Iterator<String> it = set.iterator();
while(it.hasNext()){
String key= it.next();
String[] values = params.get(key);
values[0] = values[0].trim();
params.put(key, values);
}
}
@Override
public String getParameter(String name) {
String[]values = params.get(name);
if(values == null || values.length == 0) {
return null;
}
return values[0];
}
/**
* @Title: getParameterValues
* @Description: 重写getParameterValues
* @DateTime 2020-7-23 10:31:12
*/
@Override
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(){
return bis.read();
}
}
}
第四步：利用fastjson实现json字符串转map功能
package com.codepeople.framework.util;
import java.util.ArrayList;
import java.util.HashMap;
import java.util.Iterator;
import java.util.List;
import java.util.Map;
import com.alibaba.fastjson.JSONArray;
import com.alibaba.fastjson.JSONObject;
/**
* @ClassName: StringJsonUtils
* @Description:
* @Author 刘 仁
* @DateTime 2020-7-23 10:26:28
*/
public class StringJsonUtils {
/**
* @Title: jsonStringToMap
* @Description: 把jsonString转为Map
* @Author 刘 仁
* @DateTime 2020-7-23 10:27:11
* @param jsonString
* @return
*/
public static Map<String, Object> jsonStringToMap(String jsonString) {
Map<String, Object> map = new HashMap<>();
JSONObject jsonObject = JSONObject.parseObject(jsonString);
for (Object k : jsonObject.keySet()) {
Object o = jsonObject.get(k);
if (o instanceof JSONArray) {
List<Map<String, Object>> list = new ArrayList<>();
Iterator<Object> it = ((JSONArray) o).iterator();
while (it.hasNext()) {
Object obj = it.next();
list.add(jsonStringToMap(obj.toString()));
}
map.put(k.toString(), list);
} else if (o instanceof JSONObject) {
// 如果内层是json对象的话，继续解析
map.put(k.toString(), jsonStringToMap(o.toString()));
} else {
// 如果内层是普通对象的话，直接放入map中
// map.put(k.toString(), o.toString().trim());
if (o instanceof String) {
map.put(k.toString(), o.toString().trim());
} else {
map.put(k.toString(), o);
}
}
}
return map;
}
}
主要引入的包
<!--常用工具类 -->
<dependency>
<groupId>org.apache.commons</groupId>
<artifactId>commons-lang3</artifactId>
</dependency>
<!-- 阿里JSON解析器 -->
<dependency>
<groupId>com.alibaba</groupId>
<artifactId>fastjson</artifactId>
</dependency>
<!-- io常用工具类 -->
<dependency>
<groupId>commons-io</groupId>
<artifactId>commons-io</artifactId>
</dependency>
<!-- servlet包 -->
<dependency>
<groupId>javax.servlet</groupId>
<artifactId>javax.servlet-api</artifactId>
</dependency>
测试日志
11:28:07.995 [http-nio-80-exec-17] INFO c.r.f.f.ParameterRequestWrapper - [getInputStream,54] - 去除POST请求数据两端的空格前参数：{
"idNumber": "110101201003073036",
"password": " 123456 "
}
11:28:07.997 [http-nio-80-exec-17] INFO c.r.f.f.ParameterRequestWrapper - [getInputStream,56] - 去除POST请求数据两端的空格后参数：{"password":"123456","idNumber":"110101201003073036"}
如果Filter未生效则可以直接在Springboot启动类上增加如下注解
@ServletComponentScan(basePackages = "full.package.path")
##例如
@ServletComponentScan(basePackages = "com.kelan.framework.filter")
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