Servlet Container에서 인코딩 설정하기

1. filter를 이용하기

(1) 요구사항: Container가 servlet 2.3을 지원해야 한다.

(2) 방법

(a) 아래와 같은 필터 클래스 작성

--------------------------------------------------------------------------------

package net.javajigi.filter;

import java.io.IOException;
import javax.servlet.Filter;
import javax.servlet.FilterChain;
import javax.servlet.FilterConfig;
import javax.servlet.ServletException;
import javax.servlet.ServletRequest;
import javax.servlet.ServletResponse;

/**
 * ServletRequest객체에 인코딩을 설정하는 Filter클래스.
 *
 * @web.filter name="Encoding Filter"
 *       display-name="Encoding Filter"
 *  
 * @web.filter-init-param name="encoding"
 *         value="EUC-KR"     
 *
 * @web.filter-mapping url-pattern="/*"
 *        
 */
public class EncodingFilter implements Filter {
 private String encoding = null;

 protected FilterConfig filterConfig = null;

 public void destroy() {

  this.encoding = null;
  this.filterConfig = null;

 }

 /**
  * ServletRequest객체에 web.xml에서 전달된 인코딩을 설정하는 메써드.
  */
 public void doFilter(
  ServletRequest request,
  ServletResponse response,
  FilterChain chain)
  throws IOException, ServletException {

  if (request.getCharacterEncoding() == null) {
   if (encoding != null) {
    request.setCharacterEncoding(encoding);
   }
  }

  chain.doFilter(request, response);
 }

 /**
  * web.xml에서 전달된 인코딩 값을 초기화하는 메써드.
  */
 public void init(FilterConfig filterConfig) throws ServletException {
  this.filterConfig = filterConfig;
  this.encoding = filterConfig.getInitParameter("encoding");
 }

 public FilterConfig getFilterConfig() {
  return filterConfig;
 }

 public void setFilterConfig(FilterConfig cfg) {
  filterConfig = cfg;
 }
}

--------------------------------------------------------------------------------

(b) web.xml에 아래 설정을 추가

--------------------------------------------------------------------------------

  <filter>
   <filter-name>Encoding Filter</filter-name>
   <display-name>Encoding Filter</display-name>
   <filter-class>net.javajigi.filter.EncodingFilter</filter-class>
   <init-param>
    <param-name>encoding</param-name>
    <param-value>EUC-KR</param-value>
   </init-param>
  </filter>
 
  <filter-mapping>
   <filter-name>Encoding Filter</filter-name>
   <url-pattern>/*</url-pattern>
  </filter-mapping>

--------------------------------------------------------------------------------

2. request 객체 이용

request 객체를 처리하기 전에 아래와 같이 인코딩을 적용

--------------------------------------------------------------------------------

request.setCharacterEncoding("euc-kr");

--------------------------------------------------------------------------------