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/*
* This library is part of OpenCms -
* the Open Source Content Management System
*
* Copyright (c) Alkacon Software GmbH & Co. KG (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 & Co. KG, 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.XML
* 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 covert a JSONObject into an XML text.
*
*/
public final class XML {
/** The Character '&'. */
public static final Character AMP = Character.valueOf('&');
/** The Character '''. */
public static final Character APOS = Character.valueOf('\'');
/** The Character '!'. */
public static final Character BANG = Character.valueOf('!');
/** The Character '='. */
public static final Character EQ = Character.valueOf('=');
/** The Character '>'. */
public static final Character GT = Character.valueOf('>');
/** The Character '<'. */
public static final Character LT = Character.valueOf('<');
/** The Character '?'. */
public static final Character QUEST = Character.valueOf('?');
/** The Character '"'. */
public static final Character QUOT = Character.valueOf('"');
/** The Character '/'. */
public static final Character SLASH = Character.valueOf('/');
/**
* Hidden constructor.
*/
private XML() {
// hide constructor
}
/**
* Replace special characters with XML escapes:
*
* & (ampersand) is replaced by &
* < (less than) is replaced by <
* > (greater than) is replaced by >
* " (double quote) is replaced by "
*
.
*
* @param string the string to be escaped
* @return the escaped string
*/
public static String escape(String string) {
StringBuffer sb = new StringBuffer();
for (int i = 0, len = string.length(); i < len; i++) {
char c = string.charAt(i);
switch (c) {
case '&':
sb.append("&");
break;
case '<':
sb.append("<");
break;
case '>':
sb.append(">");
break;
case '"':
sb.append(""");
break;
default:
sb.append(c);
}
}
return sb.toString();
}
/**
* Convert a well-formed (but not necessarily valid) XML string into a
* JSONObject.
*
* Some information may be lost in this transformation
* because JSON is a data format and XML is a document format. XML uses
* elements, attributes, and content text, while JSON uses unordered
* collections of name/value pairs and arrays of values. JSON does not
* does not like to distinguish between elements and attributes.
*
* Sequences of similar elements are represented as JSONArrays. Content
* text may be placed in a "content" member. Comments, prologs, DTDs, and
* <[ [ ]]>
are ignored.
*
* @param string the source string
* @return a JSONObject containing the structured data from the XML string
* @throws JSONException if something goes wrong
*/
public static JSONObject toJSONObject(String string) throws JSONException {
JSONObject o = new JSONObject();
XMLTokener x = new XMLTokener(string);
while (x.more() && x.skipPast("<")) {
parse(x, o, null);
}
return o;
}
/**
* Convert a JSONObject into a well-formed, element-normal XML string.
*
* @param o a JSONObject
* @return a string
* @throws JSONException if something goes wrong
*/
public static String toString(Object o) throws JSONException {
return toString(o, null);
}
/**
* Convert a JSONObject into a well-formed, element-normal XML string.
*
* @param o a JSONObject
* @param tagName the optional name of the enclosing tag
* @return a string
* @throws JSONException if something goes wrong
*/
public static String toString(Object o, String tagName) throws JSONException {
StringBuffer b = new StringBuffer();
int i;
JSONArray ja;
JSONObject jo;
String k;
Iterator keys;
int len;
String s;
Object v;
if (o instanceof JSONObject) {
// Emit
if (tagName != null) {
b.append('<');
b.append(tagName);
b.append('>');
}
// Loop thru the keys.
jo = (JSONObject)o;
keys = jo.keys();
while (keys.hasNext()) {
k = keys.next();
v = jo.get(k);
if (v instanceof String) {
s = (String)v;
} else {
s = null;
}
// Emit content in body
if (k.equals("content")) {
if (v instanceof JSONArray) {
ja = (JSONArray)v;
len = ja.length();
for (i = 0; i < len; i += 1) {
if (i > 0) {
b.append('\n');
}
b.append(escape(ja.get(i).toString()));
}
} else {
b.append(escape(v.toString()));
}
// Emit an array of similar keys
} else if (v instanceof JSONArray) {
ja = (JSONArray)v;
len = ja.length();
for (i = 0; i < len; i += 1) {
b.append(toString(ja.get(i), k));
}
} else if (v.equals("")) {
b.append('<');
b.append(k);
b.append("/>");
// Emit a new tag
} else {
b.append(toString(v, k));
}
}
if (tagName != null) {
// Emit the close tag
b.append("");
b.append(tagName);
b.append('>');
}
return b.toString();
// XML does not have good support for arrays. If an array appears in a place
// where XML is lacking, synthesize an element.
} else if (o instanceof JSONArray) {
ja = (JSONArray)o;
len = ja.length();
for (i = 0; i < len; ++i) {
b.append(toString(ja.opt(i), (tagName == null) ? "array" : tagName));
}
return b.toString();
} else {
s = (o == null) ? "null" : escape(o.toString());
return (tagName == null)
? "\"" + s + "\""
: (s.length() == 0) ? "<" + tagName + "/>" : "<" + tagName + ">" + s + "" + tagName + ">";
}
}
/**
* Scan the content following the named tag, attaching it to the context.
*
* @param x the XMLTokener containing the source string
* @param context the JSONObject that will include the new material
* @param name the tag name
* @return true if the close tag is processed
* @throws JSONException if something goes wrong
*/
private static boolean parse(XMLTokener x, JSONObject context, String name) throws JSONException {
char c;
int i;
String n;
JSONObject o = null;
String s;
Object t;
// Test for and skip past these forms:
//
//
//
// ... ?>
// Report errors for these forms:
// <>
// <=
// <<
t = x.nextToken();
// ");
return false;
}
x.back();
} else if (c == '[') {
t = x.nextToken();
if (t.equals("CDATA")) {
if (x.next() == '[') {
s = x.nextCDATA();
if (s.length() > 0) {
context.accumulate("content", s);
}
return false;
}
}
throw x.syntaxError("Expected 'CDATA['");
}
i = 1;
do {
t = x.nextMeta();
if (t == null) {
throw x.syntaxError("Missing '>' after ' 0);
return false;
} else if (t == QUEST) {
//
x.skipPast("?>");
return false;
} else if (t == SLASH) {
// Close tag
t = x.nextToken();
if (name == null) {
throw x.syntaxError("Mismatched close tag" + t);
}
if (!t.equals(name)) {
throw x.syntaxError("Mismatched " + name + " and " + t);
}
if (x.nextToken() != GT) {
throw x.syntaxError("Misshaped close tag");
}
return true;
} else if (t instanceof Character) {
throw x.syntaxError("Misshaped tag");
// Open tag <
} else {
n = (String)t;
t = null;
o = new JSONObject();
for (;;) {
if (t == null) {
t = x.nextToken();
}
// attribute = value
if (t instanceof String) {
s = (String)t;
t = x.nextToken();
if (t == EQ) {
t = x.nextToken();
if (!(t instanceof String)) {
throw x.syntaxError("Missing value");
}
o.accumulate(s, t);
t = null;
} else {
o.accumulate(s, "");
}
// Empty tag <.../>
} else if (t == SLASH) {
if (x.nextToken() != GT) {
throw x.syntaxError("Misshaped tag");
}
context.accumulate(n, o);
return false;
// Content, between <...> and
} else if (t == GT) {
for (;;) {
t = x.nextContent();
if (t == null) {
if (n != null) {
throw x.syntaxError("Unclosed tag " + n);
}
return false;
} else if (t instanceof String) {
s = (String)t;
if (s.length() > 0) {
o.accumulate("content", s);
}
// Nested element
} else if (t == LT) {
if (parse(x, o, n)) {
if (o.length() == 0) {
context.accumulate(n, "");
} else if ((o.length() == 1) && (o.opt("content") != null)) {
context.accumulate(n, o.opt("content"));
} else {
context.accumulate(n, o);
}
return false;
}
}
}
} else {
throw x.syntaxError("Misshaped tag");
}
}
}
}
}