/**
* Copyright 2005-2011 Noelios Technologies.
*
* The contents of this file are subject to the terms of one of the following
* open source licenses: LGPL 3.0 or LGPL 2.1 or CDDL 1.0 or EPL 1.0 (the
* "Licenses"). You can select the license that you prefer but you may not use
* this file except in compliance with one of these Licenses.
*
* You can obtain a copy of the LGPL 3.0 license at
* http://www.opensource.org/licenses/lgpl-3.0.html
*
* You can obtain a copy of the LGPL 2.1 license at
* http://www.opensource.org/licenses/lgpl-2.1.php
*
* You can obtain a copy of the CDDL 1.0 license at
* http://www.opensource.org/licenses/cddl1.php
*
* You can obtain a copy of the EPL 1.0 license at
* http://www.opensource.org/licenses/eclipse-1.0.php
*
* See the Licenses for the specific language governing permissions and
* limitations under the Licenses.
*
* Alternatively, you can obtain a royalty free commercial license with less
* limitations, transferable or non-transferable, directly at
* http://www.noelios.com/products/restlet-engine
*
* Restlet is a registered trademark of Noelios Technologies.
*/
package org.restlet.client.engine.header;
import java.util.ArrayList;
import java.util.List;
import org.restlet.client.data.Product;
/**
* User agent header reader.
*
* @author Thierry Boileau
*/
public class ProductReader {
/**
* Parses the given user agent String to a list of Product instances.
*
* @param userAgent
* @return the List of Product objects parsed from the String
* @throws IllegalArgumentException
* Thrown if the String can not be parsed as a list of Product
* instances.
*/
public static List<Product> read(String userAgent)
throws IllegalArgumentException {
final List<Product> result = new ArrayList<Product>();
if (userAgent != null) {
String token = null;
String version = null;
String comment = null;
final char[] tab = userAgent.trim().toCharArray();
StringBuilder tokenBuilder = new StringBuilder();
StringBuilder versionBuilder = null;
StringBuilder commentBuilder = null;
int index = 0;
boolean insideToken = true;
boolean insideVersion = false;
boolean insideComment = false;
for (index = 0; index < tab.length; index++) {
final char c = tab[index];
if (insideToken) {
if (((c >= 'a') && (c <= 'z'))
|| ((c >= 'A') && (c <= 'Z')) || (c == ' ')) {
tokenBuilder.append(c);
} else {
token = tokenBuilder.toString().trim();
insideToken = false;
if (c == '/') {
insideVersion = true;
versionBuilder = new StringBuilder();
} else if (c == '(') {
insideComment = true;
commentBuilder = new StringBuilder();
}
}
} else {
if (insideVersion) {
if (c != ' ') {
versionBuilder.append(c);
} else {
insideVersion = false;
version = versionBuilder.toString();
}
} else {
if (c == '(') {
insideComment = true;
commentBuilder = new StringBuilder();
} else {
if (insideComment) {
if (c == ')') {
insideComment = false;
comment = commentBuilder.toString();
result.add(new Product(token, version,
comment));
insideToken = true;
tokenBuilder = new StringBuilder();
} else {
commentBuilder.append(c);
}
} else {
result.add(new Product(token, version, null));
insideToken = true;
tokenBuilder = new StringBuilder();
tokenBuilder.append(c);
}
}
}
}
}
if (insideComment) {
comment = commentBuilder.toString();
result.add(new Product(token, version, comment));
} else {
if (insideVersion) {
version = versionBuilder.toString();
result.add(new Product(token, version, null));
} else {
if (insideToken && (tokenBuilder.length() > 0)) {
token = tokenBuilder.toString();
result.add(new Product(token, null, null));
}
}
}
}
return result;
}
/**
* Private constructor to ensure that the class acts as a true utility class
* i.e. it isn't instantiable and extensible.
*/
private ProductReader() {
}
}