org.apache.xbean.osgi.bundle.util.HeaderParser Maven / Gradle / Ivy
/**
* Licensed to the Apache Software Foundation (ASF) under one
* or more contributor license agreements. See the NOTICE file
* distributed with this work for additional information
* regarding copyright ownership. The ASF licenses this file
* to you 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.apache.xbean.osgi.bundle.util;
import java.util.ArrayList;
import java.util.HashMap;
import java.util.List;
import java.util.Map;
/**
* Utility class to parse standard OSGi headers.
*
* @version $Rev$, $Date$
*/
public class HeaderParser {
/**
* Parse a given OSGi header into a list of header elements.
*
* @param header the OSGi header to parse
* @return the list of header elements extracted from this header
*/
public static List parseHeader(String header) {
List elements = new ArrayList();
if (header == null || header.trim().length() == 0) {
return elements;
}
List clauses = parseDelimitedString(header, ",", false);
for (String clause : clauses) {
String[] tokens = clause.split(";");
if (tokens.length < 1) {
throw new IllegalArgumentException("Invalid header clause: " + clause);
}
HeaderElement elem = new HeaderElement(tokens[0].trim());
elements.add(elem);
int beginIndex = elements.size() - 1;
for (int i = 1; i < tokens.length; i++) {
int pos = tokens[i].indexOf('=');
if (pos != -1) {
if (pos > 0 && tokens[i].charAt(pos - 1) == ':') {
String name = tokens[i].substring(0, pos - 1).trim();
String value = tokens[i].substring(pos + 1).trim();
elem.addDirective(name, value);
} else {
String name = tokens[i].substring(0, pos).trim();
String value = tokens[i].substring(pos + 1).trim();
elem.addAttribute(name, value);
}
} else {
elem = new HeaderElement(tokens[i].trim());
elements.add(elem);
}
}
for (; beginIndex < elements.size() - 1; beginIndex++) {
HeaderElement headerElement = elements.get(beginIndex);
headerElement.getAttributes().putAll(elem.getAttributes());
headerElement.getDirectives().putAll(elem.getDirectives());
}
}
return elements;
}
private static List parseDelimitedString(String value, String delim, boolean includeQuotes) {
if (value == null) {
value = "";
}
List list = new ArrayList();
int CHAR = 1;
int DELIMITER = 2;
int STARTQUOTE = 4;
int ENDQUOTE = 8;
StringBuffer sb = new StringBuffer();
int expecting = (CHAR | DELIMITER | STARTQUOTE);
for (int i = 0; i < value.length(); i++) {
char c = value.charAt(i);
boolean isDelimiter = (delim.indexOf(c) >= 0);
boolean isQuote = (c == '"');
if (isDelimiter && ((expecting & DELIMITER) > 0)) {
list.add(sb.toString().trim());
sb.delete(0, sb.length());
expecting = (CHAR | DELIMITER | STARTQUOTE);
} else if (isQuote && ((expecting & STARTQUOTE) > 0)) {
if (includeQuotes) {
sb.append(c);
}
expecting = CHAR | ENDQUOTE;
} else if (isQuote && ((expecting & ENDQUOTE) > 0)) {
if (includeQuotes) {
sb.append(c);
}
expecting = (CHAR | STARTQUOTE | DELIMITER);
} else if ((expecting & CHAR) > 0) {
sb.append(c);
} else {
throw new IllegalArgumentException("Invalid delimited string: " + value);
}
}
if (sb.length() > 0) {
list.add(sb.toString().trim());
}
return list;
}
public static class HeaderElement {
private String path;
private Map attributes;
private Map directives;
public HeaderElement(String path) {
this.path = path;
this.attributes = new HashMap();
this.directives = new HashMap();
}
public String getName() {
return this.path;
}
public Map getAttributes() {
return attributes;
}
public String getAttribute(String name) {
return attributes.get(name);
}
public void addAttribute(String name, String value) {
attributes.put(name, value);
}
public Map getDirectives() {
return directives;
}
public String getDirective(String name) {
return directives.get(name);
}
public void addDirective(String name, String value) {
directives.put(name, value);
}
@Override
public String toString() {
return "HeaderElement [path=" + path + ", attributes=" + attributes + ", directives=" + directives + "]";
}
@Override
public int hashCode() {
final int prime = 31;
int result = 1;
result = prime * result + ((attributes == null) ? 0 : attributes.hashCode());
result = prime * result + ((directives == null) ? 0 : directives.hashCode());
result = prime * result + ((path == null) ? 0 : path.hashCode());
return result;
}
@Override
public boolean equals(Object obj) {
if (this == obj)
return true;
if (obj == null)
return false;
if (getClass() != obj.getClass())
return false;
HeaderElement other = (HeaderElement) obj;
if (attributes == null) {
if (other.attributes != null)
return false;
} else if (!attributes.equals(other.attributes))
return false;
if (directives == null) {
if (other.directives != null)
return false;
} else if (!directives.equals(other.directives))
return false;
if (path == null) {
if (other.path != null)
return false;
} else if (!path.equals(other.path))
return false;
return true;
}
}
}