tomcat request.getParamter() 乱码解决方案 Filter版本

啥也不说直接上代码。

web.xml配置如下

<filter>
<filter-name>encodeFilter</filter-name>
<filter-class>cn.lhl.web.filter.EncodingFilter</filter-class>
<init-param>
<param-name>encoding</param-name>
<param-value>UTF-8</param-value>
</init-param>
</filter>

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

过滤器实现类如下（自定义的内部类MyGetHttpServletRequestWrapper是关键。麻烦亲们自己弄到IDE格式化啦）

package cn.lhl.web.filter;

import java.io.IOException;
import java.io.UnsupportedEncodingException;

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

import org.apache.commons.lang.StringUtils;

public class EncodingFilter implements Filter{

//<Connector connectionTimeout="20000" port="8080" protocol="HTTP/1.1" redirectPort="8443" URIEncoding="UTF-8"/>
//URIEncoding未配置则为默认的ISO-8859-1 否则tomcatDefaultEncoding要与tomcat server.xml中配置保持一致
//如果不一致的话GET中文参数值依然会乱码

private String tomcatDefaultEncoding = "ISO-8859-1";

private String webXmlEncoding = "UTF-8";

@Override
public void destroy() {}

@Override
public void doFilter(ServletRequest req, ServletResponse resp, FilterChain chain) throws IOException, ServletException {
HttpServletRequest request = (HttpServletRequest) req;
HttpServletResponse response = (HttpServletResponse) resp;
// struts.i18n.encoding和request.setCharacterEncoding("UTF-8")只针对POST请求有效。对GET请求无效。
// 所以对于GET请求必须对request.getParameter方法进行包装修改
String method = request.getMethod();
if ("GET".equals(method)) {
request = new MyGetHttpServletRequestWrapper(request);
} else if ("POST".equals(method)) {
request.setCharacterEncoding(webXmlEncoding);
}
response.setCharacterEncoding(webXmlEncoding);
chain.doFilter(request, response);
}

@Override
public void init(FilterConfig filterConfig) throws ServletException {
//web.xml中过滤器初始化参数获取
String encoding = filterConfig.getInitParameter("encoding");
if(StringUtils.isNotBlank(encoding)) {
webXmlEncoding = encoding;
}
}

//自定义内部类用于包装request
private class MyGetHttpServletRequestWrapper extends HttpServletRequestWrapper {
public MyGetHttpServletRequestWrapper(HttpServletRequest request) {
super(request);
}

private String StringConverter(String oldString) {
String newString = null;
if (StringUtils.isNotBlank(oldString)) {
try {
newString = new String(oldString.getBytes(tomcatDefaultEncoding), webXmlEncoding);
} catch (UnsupportedEncodingException e) {
e.printStackTrace();
}
}
return newString;
}

@Override
public String getParameter(String name) {
return StringConverter(super.getParameter(name));
}

@Override
public String[] getParameterValues(String name) {
String[] oldValueArray = super.getParameterValues(name);
String[] newValueArray = null;
if (oldValueArray != null && oldValueArray.length > 0) {
newValueArray = new String[oldValueArray.length];
for (int i = 0; i < oldValueArray.length; i++) {
newValueArray[i] = StringConverter(oldValueArray[i]);
}
}
return newValueArray;
}
}
}