Filter过滤器进行统一参数处理demo
代码语言：javascript复制import org.slf4j.Logger;
import org.slf4j.LoggerFactory;
import javax.servlet.*;
import javax.servlet.http.HttpServletRequest;
import java.io.IOException;
public class ReplaceStreamFilter implements Filter {
private static final Logger log = LoggerFactory.getLogger(ReplaceStreamFilter.class);
@Override
public void init(FilterConfig filterConfig) throws ServletException {
log.info("StreamFilter初始化...");
}
@Override
public void doFilter(ServletRequest request, ServletResponse response, FilterChain chain) throws IOException, ServletException {
ServletRequest requestWrapper = null;
//获取请求中的流，将取出来的字符串，再次转换成流，然后把它放入到新request对象中,
if (request instanceof HttpServletRequest) {
log.info(">>>ChangeStudentNameRequestWrapper");
requestWrapper = new ChangeStudentNameRequestWrapper((HttpServletRequest) request);
}
// 在chain.doFiler方法中传递新的request对象
if (requestWrapper == null) {
chain.doFilter(request, response);
} else {
log.info(">>>chain.doFilter requestWrapper");
chain.doFilter(requestWrapper, response);
}
}
@Override
public void destroy() {
log.info("StreamFilter销毁...");
}
}
import com.alibaba.fastjson.JSON;
import com.alibaba.fastjson.JSONObject;
import com.example.mytester.entity.Student;
import javax.servlet.ReadListener;
import javax.servlet.ServletInputStream;
import javax.servlet.ServletRequest;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletRequestWrapper;
import java.io.*;
import java.nio.charset.Charset;
public class ChangeStudentNameRequestWrapper extends HttpServletRequestWrapper {
/**
* 存储body数据的容器
*/
private byte[] body;
/**
* 构造函数
* @param request
* @throws IOException
*/
public ChangeStudentNameRequestWrapper(HttpServletRequest request) throws IOException {
super(request);
//接下来的request使用这个
String bodyStr = getBodyString(request);
body = bodyStr.getBytes(Charset.defaultCharset());
}
/**
* 获取请求Body
*
* @param request request
* @return String
*/
public String getBodyString(final ServletRequest request) {
try {
return inputStream2String(request.getInputStream());
} catch (IOException e) {
e.printStackTrace();
throw new RuntimeException(e);
}
}
/**
* 获取请求Body
*
* @return String
*/
// public String getBodyString() {
// final InputStream inputStream = new ByteArrayInputStream(body);
// return inputStream2String(inputStream);
// }
/**
* 将inputStream里的数据读取出来并转换成字符串
*
* @param inputStream inputStream
* @return String
*/
private String inputStream2String(InputStream inputStream) {
StringBuilder sb = new StringBuilder();
BufferedReader reader = null;
try {
reader = new BufferedReader(new InputStreamReader(inputStream, Charset.defaultCharset()));
String line;
while ((line = reader.readLine()) != null) {
sb.append(line);
}
} catch (IOException e) {
e.printStackTrace();
throw new RuntimeException(e);
} finally {
if (reader != null) {
try {
reader.close();
} catch (IOException e) {
e.printStackTrace();
}
}
}
JSONObject jsonObject = JSONObject.parseObject(sb.toString());
if (jsonObject != null) {
System.out.println("json=" jsonObject.toString());
Student student = JSONObject.parseObject(jsonObject.toString(), Student.class);
System.out.println("修改之前的学生名称为：" student.getName());
student.setName("amd-modify"); //改变值
return JSON.toJSONString(student);
}
return sb.toString();
}
@Override
public BufferedReader getReader() throws IOException {
return new BufferedReader(new InputStreamReader(getInputStream()));
}
@Override
public ServletInputStream getInputStream() throws IOException {
final ByteArrayInputStream inputStream = new ByteArrayInputStream(body);
return new ServletInputStream() {
@Override
public int read() throws IOException {
return inputStream.read();
}
@Override
public boolean isFinished() {
return false;
}
@Override
public boolean isReady() {
return false;
}
@Override
public void setReadListener(ReadListener readListener) {
}
};
}
}
import java.io.Serializable;
public class Student implements Serializable{
private static final long serialVersionUID = -339516038496531943L;
private String sno;
private String name;
private String sex;
public String getSno() {
return sno;
}
public void setSno(String sno) {
this.sno = sno;
}
public String getName() {
return name;
}
public void setName(String name) {
this.name = name;
}
public String getSex() {
return sex;
}
public void setSex(String sex) {
this.sex = sex;
}
@Override
public String toString() {
return "Student{"
"sno='" sno '''
", name='" name '''
", sex='" sex '''
'}';
}
}
//注册
import org.springframework.boot.web.servlet.FilterRegistrationBean;
import org.springframework.context.annotation.Bean;
import org.springframework.context.annotation.Configuration;
import javax.servlet.Filter;
@Configuration
public class MyFilterConfig {
/**
* 注册过滤器
* 未设置addUrlPatterns，默认是全部的拦截
* @return FilterRegistrationBean
*/
@Bean
public FilterRegistrationBean someFilterRegistration() {
FilterRegistrationBean<Filter> registration = new FilterRegistrationBean<>();
registration.setFilter(replaceStreamFilter());
registration.addUrlPatterns("/changeStudentName");
registration.setName("replaceStreamFilter");
return registration;
}
/**
* 实例化StreamFilter
*
* @return Filter
*/
@Bean(name = "replaceStreamFilter")
public Filter replaceStreamFilter() {
return new ReplaceStreamFilter();
}
}
//测试
@RestController
public class TestController {
/**
* http://localhost:8080/changeStudentName
* 参数：{"sno":"1112","name":"xiaoming","sex":"man"}
* 返回：
* Student{sno='1112', name='amd-modify', sex='man'}
*
* @param student
* @return
*/
@RequestMapping(value = "/changeStudentName", method = RequestMethod.POST)
public String changeStudentName(@RequestBody Student student, HttpServletRequest request) {
return student.toString();
}
}
