package com.encoding;

import java.io.IOException;
import java.io.UnsupportedEncodingException;
import java.util.Enumeration;

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 Encoding implements Filter {
	private String EncodingName;

	public void destroy() {
		// TODO Auto-generated method stub

	}

	private String toUTF8(String str) {
		String rt = null;
		try {
			if (str != null) {
				rt = new String(str.getBytes("ISO-8859-1"), "utf-8");

			}
		} catch (UnsupportedEncodingException e) {
			e.printStackTrace();
		}

		return rt;
	}

	public void doFilter(ServletRequest arg0, ServletResponse arg1,
			FilterChain arg2) throws IOException, ServletException {
		// TODO Auto-generated method stub
		if (((HttpServletRequest) arg0).getMethod().equalsIgnoreCase("GET")) {
			//獲取所有參數
			Enumeration names = arg0.getParameterNames();
			while (names.hasMoreElements()) {
				String name = (String) names.nextElement();
				String values[] = arg0.getParameterValues(name);
				for (int i = 0; i < values.length; i++) {
					values[i] = toUTF8(values[i]);
					
				}
			}
		}
		arg0.setCharacterEncoding(EncodingName);
		arg2.doFilter(arg0, arg1);
	}

	public void init(FilterConfig arg0) throws ServletException {
		// TODO Auto-generated method stub
		EncodingName = arg0.getInitParameter("encodingName");
	}

}