/*
* Copyright 2010 david varnes.
*
* Licensed under the Apache License, version 2.0 (the "License");
* you may not use this file except in compliance with the License.
* You may obtain a copy of the License at:
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/
package org.freeswitch.esl.client.internal;
import org.jboss.netty.handler.codec.http.HttpMessageDecoder;
/**
* This parser provides a static helper method to split a standard Header field
* into the name and value parts.
* <p>
* This code was copied from the splitHeader() method in the {@link HttpMessageDecoder} class, which
* is licensed under the Apache License version 2. (Original author: Trustin Lee.)
*
* @author Trustin Lee
* @author david varnes
*/
public class HeaderParser
{
/**
* Split a header in the form
* <pre>
* Header-Name: Some_header-value
* </pre>
* into a String array.
*
* @param sb the string header to parse
* @return a String[] array with header name at 0 and header value at 1
*/
public static String[] splitHeader(String sb) {
final int length = sb.length();
int nameStart;
int nameEnd;
int colonEnd;
int valueStart;
int valueEnd;
nameStart = findNonWhitespace(sb, 0);
for (nameEnd = nameStart; nameEnd < length; nameEnd ++) {
char ch = sb.charAt(nameEnd);
if (ch == ':' || Character.isWhitespace(ch)) {
break;
}
}
for (colonEnd = nameEnd; colonEnd < length; colonEnd ++) {
if (sb.charAt(colonEnd) == ':') {
colonEnd ++;
break;
}
}
valueStart = findNonWhitespace(sb, colonEnd);
if (valueStart == length) {
return new String[] {
sb.substring(nameStart, nameEnd),
""
};
}
valueEnd = findEndOfString(sb);
return new String[] {
sb.substring(nameStart, nameEnd),
sb.substring(valueStart, valueEnd)
};
}
private static int findNonWhitespace(String sb, int offset) {
int result;
for (result = offset; result < sb.length(); result ++) {
if (!Character.isWhitespace(sb.charAt(result))) {
break;
}
}
return result;
}
private static int findEndOfString(String sb) {
int result;
for (result = sb.length(); result > 0; result --) {
if (!Character.isWhitespace(sb.charAt(result - 1))) {
break;
}
}
return result;
}
}