中文乱码是一个非常烦人的问题,没有学习Filter之前,每次都要进行转码
request.setCharacterEncoding("UTF-8");get还要进行转码.很是麻烦啊.后来学习到了Filter一下就可以只写一次,再也不用写了.妈妈再也不用担心我的乱码问题了.
另外说一下,tomcat8.0默认是UFT-8不用进行转码...
1.这个是用包装类,也可以用动态代理
import java.io.IOException;
import java.io.UnsupportedEncodingException;
import java.util.Map;
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;
/**
* 解决get和post请求 全部乱码
*/
public class GenericEncodingFilter implements Filter {
@Override
public void destroy() {
}
@Override
public void doFilter(ServletRequest request, ServletResponse response,
FilterChain chain) throws IOException, ServletException {
// 转型为与协议相关对象
HttpServletRequest httpServletRequest = (HttpServletRequest) request;
// 对request包装增强
HttpServletRequest myrequest = new MyRequest(httpServletRequest);
chain.doFilter(myrequest, response);
}
@Override
public void init(FilterConfig filterConfig) throws ServletException {
}
}
// 自定义request对象
class MyRequest extends HttpServletRequestWrapper {
private HttpServletRequest request;
private boolean hasEncode;
public MyRequest(HttpServletRequest request) {
super(request);// super必须写
this.request = request;
}
// 对需要增强方法 进行覆盖
@Override
public Map getParameterMap() {
// 先获得请求方式
String method = request.getMethod();
if (method.equalsIgnoreCase("post")) {
// post请求
try {
// 处理post乱码
request.setCharacterEncoding("utf-8");
return request.getParameterMap();
} catch (UnsupportedEncodingException e) {
e.printStackTrace();
}
} else if (method.equalsIgnoreCase("get")) {
// get请求
Map<String, String[]> parameterMap = request.getParameterMap();
if (!hasEncode) { // 确保get手动编码逻辑只运行一次
for (String parameterName : parameterMap.keySet()) {
String[] values = parameterMap.get(parameterName);
if (values != null) {
for (int i = 0; i < values.length; i++) {
try {
// 处理get乱码
values[i] = new String(values[i]
.getBytes("ISO-8859-1"), "utf-8");
} catch (UnsupportedEncodingException e) {
e.printStackTrace();
}
}
}
}
hasEncode = true;
}
return parameterMap;
}
return super.getParameterMap();
}
@Override
public String getParameter(String name) {
Map<String, String[]> parameterMap = getParameterMap();
String[] values = parameterMap.get(name);
if (values == null) {
return null;
}
return values[0]; // 取回参数的第一个值
}
@Override
public String[] getParameterValues(String name) {
Map<String, String[]> parameterMap = getParameterMap();
String[] values = parameterMap.get(name);
return values;
}
}
2.动态代理的代码就少了一些
import java.io.IOException;
import java.lang.reflect.InvocationHandler;
import java.lang.reflect.Method;
import java.lang.reflect.Proxy;
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;
public class EncodingFilter implements Filter {
public EncodingFilter() {
}
public void destroy() {
}
public void init(FilterConfig fConfig) throws ServletException {
}
public void doFilter(ServletRequest request, ServletResponse response, FilterChain chain)
throws IOException, ServletException {
final HttpServletRequest req = (HttpServletRequest) request;
HttpServletRequest myReq = (HttpServletRequest) Proxy.newProxyInstance(
EncodingFilter.class.getClassLoader(),req.getClass().getInterfaces(),
new InvocationHandler() {
public Object invoke(Object proxy, Method method, Object[] args) throws Throwable {
Object obj = null;
if(method.getName().equalsIgnoreCase("getParameter")) {
String reqMethod = req.getMethod();
if("get".equalsIgnoreCase(reqMethod)) {
String str = (String) method.invoke(req, args);
System.out.println("GET "+str);
String strUTF = new String(str.getBytes("ISO-8859-1"),"UTF-8");
System.out.println("GET "+strUTF);
return strUTF;
}else {
req.setCharacterEncoding("UTF-8");
obj = method.invoke(obj, args);
}
}else {
obj = method.invoke(req , args);
}
return obj;
}
});
chain.doFilter(myReq, response);
}
}