// Copyright (C) 1999-2001 by Jason Hunter <jhunter_AT_acm_DOT_org>.
// All rights reserved. Use of this class is limited.
// Please see the LICENSE for more information.
package com.oreilly.servlet;
import java.util.*;
import javax.servlet.http.*;
/**
* A class to simplify cookie retrieval. It can retrieve cookie values by
* name and return the value as any primitive type (no casting or parsing
* required). It can also throw an exception when a cookie is not found
* (simplifying error handling), and can accept default values (eliminating
* error handling).
* <p>
* It is used like this:
* <blockquote><pre>
* CookieParser parser = new CookieParser(req);
*
* float ratio = parser.getFloatCookie("ratio", 1.0);
*
* int count = 0;
* try {
* count = parser.getIntCookie("count");
* }
* catch (NumberFormatException e) {
* handleMalformedCount();
* }
* catch (CookieNotFoundException e) {
* handleNoCount();
* }
* </pre></blockquote>
*
* @see com.oreilly.servlet.CookieNotFoundException
*
* @author <b>Jason Hunter</b>, Copyright © 2000
* @version 1.0, 2000/03/19
*/
public class CookieParser {
private HttpServletRequest req;
private Hashtable cookieJar = new Hashtable();
/**
* Constructs a new CookieParser to handle the cookies of the
* given request.
*
* @param req the servlet request
*/
public CookieParser(HttpServletRequest req) {
this.req = req;
parseCookies();
}
// Load the cookie values into the cookies hashtable
void parseCookies() {
Cookie[] cookies = req.getCookies();
if (cookies != null) {
for (int i = 0; i < cookies.length; i++) {
String name = cookies[i].getName();
String value = cookies[i].getValue();
cookieJar.put(name, value);
}
}
}
/**
* Gets the named cookie value as a String
*
* @param name the cookie name
* @return the cookie value as a String
* @exception CookieNotFoundException if the cookie was not found
*/
public String getStringCookie(String name)
throws CookieNotFoundException {
String value = (String) cookieJar.get(name);
if (value == null)
throw new CookieNotFoundException(name + " not found");
else
return value;
}
/**
* Gets the named cookie value as a String, with a default.
* Returns the default value if the cookie is not found
*
* @param name the cookie name
* @param def the default cookie value
* @return the cookie value as a String, or the default
*/
public String getStringCookie(String name, String def) {
try { return getStringCookie(name); }
catch (Exception e) { return def; }
}
/**
* Gets the named cookie value as a boolean
*
* @param name the cookie name
* @return the cookie value as a boolean
* @exception CookieNotFoundException if the cookie was not found
*/
public boolean getBooleanCookie(String name)
throws CookieNotFoundException {
return new Boolean(getStringCookie(name)).booleanValue();
}
/**
* Gets the named cookie value as a boolean, with a default.
* Returns the default value if the cookie is not found.
*
* @param name the cookie name
* @param def the default cookie value
* @return the cookie value as a boolean, or the default
*/
public boolean getBooleanCookie(String name, boolean def) {
try { return getBooleanCookie(name); }
catch (Exception e) { return def; }
}
/**
* Gets the named cookie value as a byte
*
* @param name the cookie name
* @return the cookie value as a byte
* @exception CookieNotFoundException if the cookie was not found
* @exception NumberFormatException if the cookie value could not
* be converted to a byte
*/
public byte getByteCookie(String name)
throws CookieNotFoundException, NumberFormatException {
return Byte.parseByte(getStringCookie(name));
}
/**
* Gets the named cookie value as a byte, with a default.
* Returns the default value if the cookie is not found or cannot
* be converted to a byte.
*
* @param name the cookie name
* @param def the default cookie value
* @return the cookie value as a byte, or the default
*/
public byte getByteCookie(String name, byte def) {
try { return getByteCookie(name); }
catch (Exception e) { return def; }
}
/**
* Gets the named cookie value as a char
*
* @param name the cookie name
* @return the cookie value as a char
* @exception CookieNotFoundException if the cookie was not found
*/
public char getCharCookie(String name)
throws CookieNotFoundException {
String param = getStringCookie(name);
if (param.length() == 0)
throw new CookieNotFoundException(name + " is empty string");
else
return (param.charAt(0));
}
/**
* Gets the named cookie value as a char, with a default.
* Returns the default value if the cookie is not found.
*
* @param name the cookie name
* @param def the default cookie value
* @return the cookie value as a char, or the default
*/
public char getCharCookie(String name, char def) {
try { return getCharCookie(name); }
catch (Exception e) { return def; }
}
/**
* Gets the named cookie value as a double
*
* @param name the cookie name
* @return the cookie value as a double
* @exception CookieNotFoundException if the cookie was not found
* @exception NumberFormatException if the cookie could not be converted
* to a double
*/
public double getDoubleCookie(String name)
throws CookieNotFoundException, NumberFormatException {
return new Double(getStringCookie(name)).doubleValue();
}
/**
* Gets the named cookie value as a double, with a default.
* Returns the default value if the cookie is not found.
*
* @param name the cookie name
* @param def the default cookie value
* @return the cookie value as a double, or the default
*/
public double getDoubleCookie(String name, double def) {
try { return getDoubleCookie(name); }
catch (Exception e) { return def; }
}
/**
* Gets the named cookie value as a float
*
* @param name the cookie name
* @return the cookie value as a float
* @exception CookieNotFoundException if the cookie was not found
* @exception NumberFormatException if the cookie could not be converted
* to a float
*/
public float getFloatCookie(String name)
throws CookieNotFoundException, NumberFormatException {
return new Float(getStringCookie(name)).floatValue();
}
/**
* Gets the named cookie value as a float, with a default.
* Returns the default value if the cookie is not found.
*
* @param name the cookie name
* @param def the default cookie value
* @return the cookie value as a float, or the default
*/
public float getFloatCookie(String name, float def) {
try { return getFloatCookie(name); }
catch (Exception e) { return def; }
}
/**
* Gets the named cookie value as a int
*
* @param name the cookie name
* @return the cookie value as a int
* @exception CookieNotFoundException if the cookie was not found
* @exception NumberFormatException if the cookie could not be converted
* to a int
*/
public int getIntCookie(String name)
throws CookieNotFoundException, NumberFormatException {
return Integer.parseInt(getStringCookie(name));
}
/**
* Gets the named cookie value as a int, with a default.
* Returns the default value if the cookie is not found.
*
* @param name the cookie name
* @param def the default cookie value
* @return the cookie value as a int, or the default
*/
public int getIntCookie(String name, int def) {
try { return getIntCookie(name); }
catch (Exception e) { return def; }
}
/**
* Gets the named cookie value as a long
*
* @param name the cookie name
* @return the cookie value as a long
* @exception CookieNotFoundException if the cookie was not found
* @exception NumberFormatException if the cookie could not be converted
* to a long
*/
public long getLongCookie(String name)
throws CookieNotFoundException, NumberFormatException {
return Long.parseLong(getStringCookie(name));
}
/**
* Gets the named cookie value as a long, with a default.
* Returns the default value if the cookie is not found.
*
* @param name the cookie name
* @param def the default cookie value
* @return the cookie value as a long, or the default
*/
public long getLongCookie(String name, long def) {
try { return getLongCookie(name); }
catch (Exception e) { return def; }
}
/**
* Gets the named cookie value as a short
*
* @param name the cookie name
* @return the cookie value as a short
* @exception CookieNotFoundException if the cookie was not found
* @exception NumberFormatException if the cookie could not be converted
* to a short
*/
public short getShortCookie(String name)
throws CookieNotFoundException, NumberFormatException {
return Short.parseShort(getStringCookie(name));
}
/**
* Gets the named cookie value as a short, with a default.
* Returns the default value if the cookie is not found.
*
* @param name the cookie name
* @param def the default cookie value
* @return the cookie value as a short, or the default
*/
public short getShortCookie(String name, short def) {
try { return getShortCookie(name); }
catch (Exception e) { return def; }
}
}