/*
* @(#)MimeTypeParameterList.java 1.0 November 2, 2003
*
* Copyright (c) 2003 Werner Randelshofer
* Hausmatt 10, Immensee, CH-6405, Switzerland.
* All rights reserved.
*
* The copyright of this software is owned by Werner Randelshofer.
* You may not use, copy or modify this software, except in
* accordance with the license agreement you entered into with
* Werner Randelshofer. For details see accompanying license terms.
*/
package ch.randelshofer.gui.datatransfer;
import java.util.Enumeration;
import java.util.Hashtable;
import java.util.Iterator;
import java.util.Map;
import java.util.Set;
/**
* An object that encapsualtes the parameter list of a MimeType
* as defined in RFC 2045 and 2046.
* <p>
* Implementation taken from java.awt.datatransfer.MimeTypeParameterList.java 1.12 01/12/03
*
* @author Werner Randelshofer
* @version 1.0 November 2, 2003 Created.
*/
class MimeTypeParameterList implements Cloneable {
/**
* Default constructor.
*/
public MimeTypeParameterList() {
parameters = new Hashtable();
}
public MimeTypeParameterList(String rawdata)
throws MimeTypeParseException
{
parameters = new Hashtable();
// now parse rawdata
parse(rawdata);
}
public int hashCode() {
int code = Integer.MAX_VALUE/45; // "random" value for empty lists
String paramName = null;
Enumeration enm = this.getNames();
while (enm.hasMoreElements()) {
paramName = (String)enm.nextElement();
code += paramName.hashCode();
code += this.get(paramName).hashCode();
}
return code;
} // hashCode()
/**
* Two parameter lists are considered equal if they have exactly
* the same set of parameter names and associated values. The
* order of the parameters is not considered.
*/
public boolean equals(Object thatObject) {
//System.out.println("MimeTypeParameterList.equals("+this+","+thatObject+")");
if (!(thatObject instanceof MimeTypeParameterList)) {
return false;
}
MimeTypeParameterList that = (MimeTypeParameterList)thatObject;
if (this.size() != that.size()) {
return false;
}
String name = null;
String thisValue = null;
String thatValue = null;
Set entries = parameters.entrySet();
Iterator iterator = entries.iterator();
Map.Entry entry = null;
while (iterator.hasNext()) {
entry = (Map.Entry)iterator.next();
name = (String)entry.getKey();
thisValue = (String)entry.getValue();
thatValue = (String)that.parameters.get(name);
if ((thisValue == null) || (thatValue == null)) {
// both null -> equal, only one null -> not equal
if (thisValue != thatValue) {
return false;
}
} else if (!thisValue.equals(thatValue)) {
return false;
}
} // while iterator
return true;
} // equals()
/**
* A routine for parsing the parameter list out of a String.
*/
protected void parse(String rawdata) throws MimeTypeParseException {
int length = rawdata.length();
if(length > 0) {
int currentIndex = skipWhiteSpace(rawdata, 0);
int lastIndex = 0;
if(currentIndex < length) {
char currentChar = rawdata.charAt(currentIndex);
while ((currentIndex < length) && (currentChar == ';')) {
String name;
String value;
boolean foundit;
// eat the ';'
++currentIndex;
// now parse the parameter name
// skip whitespace
currentIndex = skipWhiteSpace(rawdata, currentIndex);
if(currentIndex < length) {
// find the end of the token char run
lastIndex = currentIndex;
currentChar = rawdata.charAt(currentIndex);
while((currentIndex < length) && isTokenChar(currentChar)) {
++currentIndex;
currentChar = rawdata.charAt(currentIndex);
}
name = rawdata.substring(lastIndex, currentIndex).toLowerCase();
// now parse the '=' that separates the name from the value
// skip whitespace
currentIndex = skipWhiteSpace(rawdata, currentIndex);
if((currentIndex < length) && (rawdata.charAt(currentIndex) == '=')) {
// eat it and parse the parameter value
++currentIndex;
// skip whitespace
currentIndex = skipWhiteSpace(rawdata, currentIndex);
if(currentIndex < length) {
// now find out whether or not we have a quoted value
currentChar = rawdata.charAt(currentIndex);
if(currentChar == '"') {
// yup it's quoted so eat it and capture the quoted string
++currentIndex;
lastIndex = currentIndex;
if(currentIndex < length) {
// find the next unescqped quote
foundit = false;
while((currentIndex < length) && !foundit) {
currentChar = rawdata.charAt(currentIndex);
if(currentChar == '\\') {
// found an escape sequence so pass this and the next character
currentIndex += 2;
} else if(currentChar == '"') {
// foundit!
foundit = true;
} else {
++currentIndex;
}
}
if(currentChar == '"') {
value = unquote(rawdata.substring(lastIndex, currentIndex));
// eat the quote
++currentIndex;
} else {
throw new MimeTypeParseException("Encountered unterminated quoted parameter value.");
}
} else {
throw new MimeTypeParseException("Encountered unterminated quoted parameter value.");
}
} else if(isTokenChar(currentChar)) {
// nope it's an ordinary token so it ends with a non-token char
lastIndex = currentIndex;
foundit = false;
while((currentIndex < length) && !foundit) {
currentChar = rawdata.charAt(currentIndex);
if(isTokenChar(currentChar)) {
++currentIndex;
} else {
foundit = true;
}
}
value = rawdata.substring(lastIndex, currentIndex);
} else {
// it ain't a value
throw new MimeTypeParseException("Unexpected character encountered at index " + currentIndex);
}
// now put the data into the hashtable
parameters.put(name, value);
} else {
throw new MimeTypeParseException("Couldn't find a value for parameter named " + name);
}
} else {
throw new MimeTypeParseException("Couldn't find the '=' that separates a parameter name from its value.");
}
} else {
throw new MimeTypeParseException("Couldn't find parameter name");
}
// setup the next iteration
currentIndex = skipWhiteSpace(rawdata, currentIndex);
if(currentIndex < length) {
currentChar = rawdata.charAt(currentIndex);
}
}
if(currentIndex < length) {
throw new MimeTypeParseException("More characters encountered in input than expected.");
}
}
}
}
/**
* return the number of name-value pairs in this list.
*/
public int size() {
return parameters.size();
}
/**
* Determine whether or not this list is empty.
*/
public boolean isEmpty() {
return parameters.isEmpty();
}
/**
* Retrieve the value associated with the given name, or null if there
* is no current association.
*/
public String get(String name) {
return (String)parameters.get(name.trim().toLowerCase());
}
/**
* Set the value to be associated with the given name, replacing
* any previous association.
*/
public void set(String name, String value) {
parameters.put(name.trim().toLowerCase(), value);
}
/**
* Remove any value associated with the given name.
*/
public void remove(String name) {
parameters.remove(name.trim().toLowerCase());
}
/**
* Retrieve an enumeration of all the names in this list.
*/
public Enumeration getNames() {
return parameters.keys();
}
public String toString() {
StringBuffer buffer = new StringBuffer();
buffer.ensureCapacity(parameters.size() * 16); // heuristic: 8 characters per field
Enumeration keys = parameters.keys();
while(keys.hasMoreElements())
{
buffer.append("; ");
String key = (String)keys.nextElement();
buffer.append(key);
buffer.append('=');
buffer.append(quote((String)parameters.get(key)));
}
return buffer.toString();
}
/**
* @return a clone of this object
*/
public Object clone() {
MimeTypeParameterList newObj = null;
try {
newObj = (MimeTypeParameterList)super.clone();
} catch (CloneNotSupportedException cannotHappen) {
}
newObj.parameters = (Hashtable)parameters.clone();
return newObj;
}
private Hashtable parameters;
// below here be scary parsing related things
/**
* Determine whether or not a given character belongs to a legal token.
*/
private static boolean isTokenChar(char c) {
return ((c > 040) && (c < 0177)) && (TSPECIALS.indexOf(c) < 0);
}
/**
* return the index of the first non white space character in
* rawdata at or after index i.
*/
private static int skipWhiteSpace(String rawdata, int i) {
int length = rawdata.length();
if (i < length) {
char c = rawdata.charAt(i);
while ((i < length) && Character.isWhitespace(c)) {
++i;
c = rawdata.charAt(i);
}
}
return i;
}
/**
* A routine that knows how and when to quote and escape the given value.
*/
private static String quote(String value) {
boolean needsQuotes = false;
// check to see if we actually have to quote this thing
int length = value.length();
for(int i = 0; (i < length) && !needsQuotes; ++i) {
needsQuotes = !isTokenChar(value.charAt(i));
}
if(needsQuotes) {
StringBuffer buffer = new StringBuffer();
buffer.ensureCapacity((int)(length * 1.5));
// add the initial quote
buffer.append('"');
// add the properly escaped text
for(int i = 0; i < length; ++i) {
char c = value.charAt(i);
if((c == '\\') || (c == '"')) {
buffer.append('\\');
}
buffer.append(c);
}
// add the closing quote
buffer.append('"');
return buffer.toString();
}
else
{
return value;
}
}
/**
* A routine that knows how to strip the quotes and escape sequences from the given value.
*/
private static String unquote(String value) {
int valueLength = value.length();
StringBuffer buffer = new StringBuffer();
buffer.ensureCapacity(valueLength);
boolean escaped = false;
for(int i = 0; i < valueLength; ++i) {
char currentChar = value.charAt(i);
if(!escaped && (currentChar != '\\')) {
buffer.append(currentChar);
} else if(escaped) {
buffer.append(currentChar);
escaped = false;
} else {
escaped = true;
}
}
return buffer.toString();
}
/**
* A string that holds all the special chars.
*/
private static final String TSPECIALS = "()<>@,;:\\\"/[]?=";
}