java spring boot 过滤器重写请求参数、添加参数、修改参数、json参数
目录
一、普通参数:ParameterRequestWrapper
二、HttpHelper请求处理字符串工具类
三、实体json参数：RequestWrapper
四、过滤器：PostFilter
五、Controller
一、普通参数:ParameterRequestWrapper
| import javax.servlet.http.HttpServletRequest; import javax.servlet.http.HttpServletRequestWrapper; import java.util.Enumeration; import java.util.Map; import java.util.Vector; /** * 普通参数设置 * */ public class ParameterRequestWrapper extends HttpServletRequestWrapper { private Map params; public ParameterRequestWrapper(HttpServletRequest request, Map newParams) { super(request); this.params = newParams; } @Override public Map getParameterMap() { return params; } @Override public Enumeration getParameterNames() { Vector l = new Vector(params.keySet()); return l.elements(); } @Override public String[] getParameterValues(String name) { Object v = params.get(name); if (v == null) { return null; } else if (v instanceof String[]) { return (String[]) v; } else if (v instanceof String) { return new String[]{(String) v}; } else { return new String[]{v.toString()}; } } @Override public String getParameter(String name) { Object v = params.get(name); if (v == null) { return null; } else if (v instanceof String[]) { String[] strArr = (String[]) v; if (strArr.length > 0) { return strArr[0]; } else { return null; } } else if (v instanceof String) { return (String) v; } else { return v.toString(); } } } |
二、HttpHelper请求处理字符串工具类
| import javax.servlet.ServletRequest; import java.io.BufferedReader; import java.io.IOException; import java.io.InputStream; import java.io.InputStreamReader; import java.nio.charset.Charset; /** * 请求处理工具类 * */ public class HttpHelper { public static String getBodyString(ServletRequest request) { StringBuilder sb = new StringBuilder(); InputStream inputStream = null; BufferedReader reader = null; try { inputStream = request.getInputStream(); reader = new BufferedReader(new InputStreamReader(inputStream, Charset.forName("UTF-8"))); String line = ""; while ((line = reader.readLine()) != null) { sb.append(line); } } catch (IOException e) { LogUtils.error(e); } finally { if (inputStream != null) { try { inputStream.close(); } catch (IOException e) { LogUtils.error(e); } } if (reader != null) { try { reader.close(); } catch (IOException e) { LogUtils.error(e); } } } return sb.toString()/*.replaceAll(" ","")*/; } } |
三、实体json参数：RequestWrapper
| import com.hean.iot.platform.utils.HttpHelper; import javax.servlet.ServletInputStream; import javax.servlet.http.HttpServletRequest; import javax.servlet.http.HttpServletRequestWrapper; import java.io.BufferedReader; import java.io.ByteArrayInputStream; import java.io.IOException; import java.io.InputStreamReader; import java.nio.charset.Charset; /** * 请求参数重写 * */ public class RequestWrapper extends HttpServletRequestWrapper { private byte[] body; public RequestWrapper(HttpServletRequest request) { super(request); body = HttpHelper.getBodyString(request).getBytes(Charset.forName("UTF-8")); } @Override public BufferedReader getReader() throws IOException { return new BufferedReader(new InputStreamReader(getInputStream())); } /** * 重写获取 输入流的方法，保证流可写可读多次 * @return * @throws IOException */ @Override public ServletInputStream getInputStream() throws IOException { final ByteArrayInputStream bais = new ByteArrayInputStream(body); return new ServletInputStream() { @Override public int read() throws IOException { return bais.read(); } }; } public byte[] getBody() { return body; } public void setBody(byte[] body) { this.body = body; } } |
四、过滤器：PostFilter
| import com.alibaba.fastjson.JSON; import com.alibaba.fastjson.JSONObject; import com.hean.iot.platform.model.RequestWrapper; import com.hean.iot.platform.session.SessionBeanService; import org.springframework.context.annotation.Configuration; import javax.servlet.*; import javax.servlet.annotation.WebFilter; import javax.servlet.http.HttpServletRequest; import java.io.BufferedReader; import java.io.IOException; import java.util.HashMap; /** * 过滤器 * */ @Configuration @WebFilter(filterName = "authFilter", urlPatterns = {"/*"}) public class PostFilter implements Filter { @Override public void doFilter(ServletRequest request, ServletResponse response, FilterChain chain) throws IOException, ServletException { /* * @Date: 2021/1/18 14:59 * Step 1: 重写 RequestWrapper，重写获取流的方法 */ RequestWrapper requestWrapper = new RequestWrapper((HttpServletRequest) request); /* * @Date: 2021/1/18 14:59 * Step 2: 读取输入流，将所需信息写入 * json形式参数填充（这里新增customerId的键值） */ StringBuffer buffer = new StringBuffer(); String line = null; BufferedReader reader = null; reader = requestWrapper.getReader(); while ((line = reader.readLine()) != null) { buffer.append(line); } JSONObject object = JSON.parseObject(buffer.toString()); object.put("customerId", SessionBeanService.getCustomerId()); requestWrapper.setBody(object.toString().getBytes()); /* * @Date: 2021/1/18 15:00 * Step 3: 普通形式参数填充（这里新增customerId的键值） */ HashMap parameterMap = new HashMap(requestWrapper.getParameterMap()); parameterMap.put("customerId", new String[]{SessionBeanService.getCustomerId().toString()}); ParameterRequestWrapper newRequest = new ParameterRequestWrapper(requestWrapper, parameterMap); /** * 过滤跳转 */ chain.doFilter(newRequest, response); } @Override public void destroy() { } @Override public void init(FilterConfig config) throws ServletException { } } |
五、Controller
| @RequestMapping("/findDropDown.do") @ResponseBody public BaseResult findAlarmGradeDropDown(@RequestBody DropDownDto condition, String customerId) throws Exception { return rslt; } |
这样，不管是@RequestBody 参数，还是普通参数，都能得到自己设置的值。
也就可以通过这样的方式设置所有请求的公共参数。
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