/*
* This library is part of OpenCms -
* the Open Source Content Management System
*
* Copyright (c) Alkacon Software GmbH (http://www.alkacon.com)
*
* This library is free software; you can redistribute it and/or
* modify it under the terms of the GNU Lesser General Public
* License as published by the Free Software Foundation; either
* version 2.1 of the License, or (at your option) any later version.
*
* This library is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
* Lesser General Public License for more details.
*
* For further information about Alkacon Software GmbH, please see the
* company website: http://www.alkacon.com
*
* For further information about OpenCms, please see the
* project website: http://www.opencms.org
*
* You should have received a copy of the GNU Lesser General Public
* License along with this library; if not, write to the Free Software
* Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
*
* This file is based on:
* org.json.JSONML
* from the JSON in Java implementation.
*
* Copyright (c) 2002 JSON.org
*
* Permission is hereby granted, free of charge, to any person obtaining a copy
* of this software and associated documentation files (the "Software"), to deal
* in the Software without restriction, including without limitation the rights
* to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
* copies of the Software, and to permit persons to whom the Software is
* furnished to do so, subject to the following conditions:
*
* The above copyright notice and this permission notice shall be included in all
* copies or substantial portions of the Software.
*
* The Software shall be used for Good, not Evil.
*
* THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
* IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
* FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
* AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
* LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
* OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
* SOFTWARE.
*/
package org.opencms.json;
import java.util.Iterator;
/**
* This provides static methods to convert an XML text into a JSONObject,
* and to convert a JSONObject into an XML text using the JsonML transform.<p>
*
*/
public final class JSONML {
/**
* Hidden constructor.<p>
*/
private JSONML() {
// hidden constructor
}
/**
* Convert a well-formed (but not necessarily valid) XML string into a
* JSONArray using the JsonML transform.<p>
*
* Each XML tag is represented as
* a JSONArray in which the first element is the tag name. If the tag has
* attributes, then the second element will be JSONObject containing the
* name/value pairs. If the tag contains children, then strings and
* JSONArrays will represent the child tags.
* Comments, prologs, DTDs, and <code><[ [ ]]></code> are ignored.<p>
*
* @param string the source string
* @return a JSONArray containing the structured data from the XML string.
* @throws JSONException if something goes wrong
*/
public static JSONArray toJSONArray(String string) throws JSONException {
return toJSONArray(new XMLTokener(string));
}
/**
* Convert a well-formed (but not necessarily valid) XML string into a
* JSONArray using the JsonML transform.<p>
*
* Each XML tag is represented as
* a JSONArray in which the first element is the tag name. If the tag has
* attributes, then the second element will be JSONObject containing the
* name/value pairs. If the tag contains children, then strings and
* JSONArrays will represent the child content and tags.
* Comments, prologs, DTDs, and <code><[ [ ]]></code> are ignored.<p>
*
* @param x an XMLTokener
* @return a JSONArray containing the structured data from the XML string
* @throws JSONException if something goes wrong
*/
public static JSONArray toJSONArray(XMLTokener x) throws JSONException {
return parse(x, null);
}
/**
* Reverse the JSONML transformation, making an XML text from a JSONArray.<p>
*
* @param ja a JSONArray
* @return an XML string
* @throws JSONException if something goes wrong
*/
public static String toString(JSONArray ja) throws JSONException {
StringBuffer b = new StringBuffer();
stringify(ja, b);
return b.toString();
}
/**
* Parse XML values and store them in a JSONArray.<p>
*
* @param x the XMLTokener containing the source string
* @param ja the JSONArray that is containing the current tag or null
* if we are at the outermost level
* @return a JSONArray if the value is the outermost tag, otherwise null
* @throws JSONException if something goes wrong
*/
private static JSONArray parse(XMLTokener x, JSONArray ja) throws JSONException {
char c;
int i;
String s;
Object t;
// Test for and skip past these forms:
// <!-- ... -->
// <! ... >
// <![ ... ]]>
// <? ... ?>
// Report errors for these forms:
// <>
// <=
// <<
while (true) {
t = x.nextContent();
if (t == XML.LT) {
t = x.nextToken();
if (t instanceof Character) {
// <!
if (t == XML.BANG) {
c = x.next();
if (c == '-') {
if (x.next() == '-') {
x.skipPast("-->");
}
x.back();
} else if (c == '[') {
t = x.nextToken();
if (t.equals("CDATA") && x.next() == '[') {
x.nextCDATA();
} else {
throw x.syntaxError("Expected 'CDATA['");
}
} else {
i = 1;
do {
t = x.nextMeta();
if (t == null) {
throw x.syntaxError("Missing '>' after '<!'.");
} else if (t == XML.LT) {
i += 1;
} else if (t == XML.GT) {
i -= 1;
}
} while (i > 0);
}
} else if (t == XML.QUEST) {
// <?
x.skipPast("?>");
} else if (t == XML.SLASH) {
// Close tag </
t = x.nextToken();
if (ja == null) {
throw x.syntaxError("Mismatched close tag '" + t + "'");
}
if (!t.equals(ja.get(0))) {
throw x.syntaxError("Mismatched '" + ja.get(0) + "' and '" + t + "'");
}
if (x.nextToken() != XML.GT) {
throw x.syntaxError("Misshaped close tag");
}
return null;
} else {
throw x.syntaxError("Misshaped tag");
}
// Open tag <
} else {
JSONArray newja = new JSONArray();
JSONObject attributes = new JSONObject();
if (ja != null) {
ja.put(newja);
}
newja.put(t);
t = null;
for (;;) {
if (t == null) {
t = x.nextToken();
}
if (t == null) {
throw x.syntaxError("Misshaped tag");
}
if (!(t instanceof String)) {
break;
}
// attribute = value
s = (String)t;
t = x.nextToken();
if (t == XML.EQ) {
t = x.nextToken();
if (!(t instanceof String)) {
throw x.syntaxError("Missing value");
}
attributes.accumulate(s, t);
t = null;
} else {
attributes.accumulate(s, "");
}
}
if (attributes.length() > 0) {
newja.put(attributes);
}
// Empty tag <.../>
if (t == XML.SLASH) {
if (x.nextToken() != XML.GT) {
throw x.syntaxError("Misshaped tag");
}
if (ja == null) {
return newja;
}
// Content, between <...> and </...>
} else if (t == XML.GT) {
parse(x, newja);
if (ja == null) {
return newja;
}
} else {
throw x.syntaxError("Misshaped tag");
}
}
} else {
if (ja != null) {
ja.put(t);
}
}
}
}
/**
* Reverse the JSONML transformation, making an XML text from a JSONArray.<p>
*
* @param ja a JSONArray
* @param b a string buffer in which to build the text
* @throws JSONException if something goes wrong
*/
private static void stringify(JSONArray ja, StringBuffer b) throws JSONException {
int i;
JSONObject jo;
String k;
Iterator keys;
int len;
Object o;
Object v;
// Emit <tagName>
b.append('<');
b.append(ja.get(0));
o = ja.opt(1);
if (o instanceof JSONObject) {
// Loop thru the attributes.
jo = (JSONObject)o;
keys = jo.keys();
while (keys.hasNext()) {
k = keys.next().toString();
v = jo.get(k).toString();
b.append(' ');
b.append(k);
b.append("=\"");
b.append(XML.escape((String)v));
b.append('"');
}
i = 2;
} else {
i = 1;
}
len = ja.length();
if (i >= len) {
b.append("/>");
} else {
b.append('>');
while (i < len) {
v = ja.get(i);
if (v instanceof JSONArray) {
stringify((JSONArray)v, b);
} else {
b.append(XML.escape(v.toString()));
}
i += 1;
}
b.append("</");
b.append(ja.get(0));
b.append('>');
}
}
}