package?com;

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;

public?class?CharacterEncodingFilter?implements?Filter?{

	protected?String?encoding?=?null;//?定義編碼格式變量
	protected?FilterConfig?filterConfig?=?null;//?定義過濾器配置對象

	public?void?init（FilterConfig?filterConfig）?throws?ServletException?{
		this.filterConfig?=?filterConfig;?//?初始化過濾器配置對象
		this.encoding?=?filterConfig.getInitParameter（“encoding“）;//?獲取配置文件中指定的編碼格式
	}

	//?過濾器的接口方法，用于執行過濾業務
	public?void?doFilter（ServletRequest?request?ServletResponse?response
			FilterChain?chain）?throws?IOException?ServletException?{
		if?（encoding?!=?null）?{
			request.setCharacterEncoding（encoding）;?//?設置請求的編碼
			response.setContentType（“text/html;?charset=“?+?encoding）;//?設置應答對象的內容類型（包括編碼格式）
		}
		chain.doFilter（request?response）;?//?傳遞給下一個過濾器
	}

	public?void?destroy（）?{
		this.encoding?=?null;
		this.filterConfig?=?null;
	}
}