urldecoder.java

这个是网络上下载的一个struct框架的程序

// Decompiled by DJ v3.5.5.77 Copyright 2003 Atanas Neshkov  Date: 2003-6-23 10:56:27
// Home Page : http://members.fortunecity.com/neshkov/dj.html  - Check often for new version!
// Decompiler options: packimports(3) 
// Source File Name:   URLDecoder.java

package com.struts2.framework.util;

import java.io.UnsupportedEncodingException;

// Referenced classes of package org.fat32.util.net:
//            URLEncoder

public class URLDecoder {

	/**
	 * @deprecated Method decode is deprecated
	 */

	public static String decode(String s) {
		String str = null;
		try {
			str = decode(s, dfltEncName);
		} catch (UnsupportedEncodingException unsupportedencodingexception) {
		}
		return str;
	}

	public static String decode(String s, String enc)
			throws UnsupportedEncodingException {
		boolean needToChange = false;
		StringBuffer sb = new StringBuffer();
		int numChars = s.length();
		int i = 0;
		if (enc.length() == 0)
			throw new UnsupportedEncodingException(
					"URLDecoder: empty string enc parameter");
		while (i < numChars) {
			char c = s.charAt(i);
			switch (c) {
			case 43: // '+'
				sb.append(' ');
				i++;
				needToChange = true;
				break;

			case 37: // '%'
				try {
					byte bytes[] = new byte[(numChars - i) / 3];
					int pos = 0;
					while (i + 2 < numChars && c == '%') {
						bytes[pos++] = (byte) Integer.parseInt(s.substring(
								i + 1, i + 3), 16);
						if ((i += 3) < numChars)
							c = s.charAt(i);
					}
					if (i < numChars && c == '%')
						throw new IllegalArgumentException(
								"URLDecoder: Incomplete trailing escape (%) pattern");
					sb.append(new String(bytes, 0, pos, enc));
				} catch (NumberFormatException e) {
					throw new IllegalArgumentException(
							"URLDecoder: Illegal hex characters in escape (%) pattern - "
									+ e.getMessage());
				}
				needToChange = true;
				break;

			case 38: // '&'
			case 39: // '\''
			case 40: // '('
			case 41: // ')'
			case 42: // '*'
			default:
				sb.append(c);
				i++;
				break;
			}
		}
		return needToChange ? sb.toString() : s;
	}

	public URLDecoder() {
	}

	static String dfltEncName;

	static {
		dfltEncName = URLEncoder.dfltEncName;
	}
}