JsonOperationNormalizer.java
/*
*
* 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 WARRANT
IES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*
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
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package org.odftoolkit.odfdom.changes;
import static org.odftoolkit.odfdom.changes.OperationConstants.OPK_EDITOR;
import static org.odftoolkit.odfdom.changes.OperationConstants.OPK_END;
import static org.odftoolkit.odfdom.changes.OperationConstants.OPK_NAME;
import static org.odftoolkit.odfdom.changes.OperationConstants.OPK_OPERATIONS;
import static org.odftoolkit.odfdom.changes.OperationConstants.OPK_START;
import static org.odftoolkit.odfdom.changes.OperationConstants.OPK_STYLE_ID;
import static org.odftoolkit.odfdom.changes.OperationConstants.OPK_TYPE;
import static org.odftoolkit.odfdom.changes.OperationConstants.OPK_VERSION;
import static org.odftoolkit.odfdom.changes.OperationConstants.OPK_VERSION_BRANCH;
import static org.odftoolkit.odfdom.changes.OperationConstants.OPK_VERSION_TIME;
import static org.odftoolkit.odfdom.changes.OperationConstants.OP_STYLE;
import java.text.Collator;
import java.util.ArrayList;
import java.util.Collections;
import java.util.Comparator;
import java.util.HashSet;
import java.util.Iterator;
import java.util.List;
import java.util.Locale;
import java.util.Set;
import java.util.SortedSet;
import java.util.TreeSet;
import java.util.logging.Level;
import java.util.logging.Logger;
import org.json.JSONArray;
import org.json.JSONException;
import org.json.JSONObject;
import org.json.JSONString;
/**
* Normalizes the content of JSONObject to make it comparable.
*
* @author svante.schubertATgmail.com
*/
public class JsonOperationNormalizer {
// If in an operation a map contains one of the following keys, they will be added at the
// beginning for better readability!
private static final String[] SORTING_SEQUENCE_OF_KEYS = {
OPK_NAME, OPK_START, OPK_END, OPK_TYPE, OPK_STYLE_ID
};
private static final Logger LOG = Logger.getLogger(JsonOperationNormalizer.class.getName());
/**
* Make a JSON text of this JSONObject. For compactness, no whitespace is added. If this would not
* result in a syntactically correct JSON text, then null will be returned instead.
*
* <p>Warning: This method assumes that the data structure is acyclical.
*
* @return a printable, displayable, portable, transmittable representation of the object,
* beginning with <code>{</code> <small>(left brace)</small> and ending with <code>}
* </code> <small>(right brace)</small>.
*/
public static String asString(JSONObject jsonObject, Boolean isTest) {
if (jsonObject.has(OPK_OPERATIONS)) {
// removing for test output & references the most varying attributes to reduce noise
jsonObject.remove(OPK_VERSION);
jsonObject.remove(OPK_VERSION_TIME);
jsonObject.remove(OPK_VERSION_BRANCH);
jsonObject.remove(OPK_EDITOR);
}
StringBuilder sb = new StringBuilder("{");
Iterator<String> keys = getSortedIterator(jsonObject);
while (keys.hasNext()) {
String key = keys.next();
if (key.equals(OPK_OPERATIONS)) {
sb.append("\"" + OPK_OPERATIONS + "\":[\n");
try {
JSONArray ops = jsonObject.getJSONArray(OPK_OPERATIONS);
sb.append(normalizeOperations(ops));
} catch (JSONException ex) {
Logger.getLogger(JsonOperationNormalizer.class.getName()).log(Level.SEVERE, null, ex);
}
sb.append("\n]");
} else {
try {
if (sb.length() > 1) {
sb.append(',');
}
sb.append('"');
sb.append(key);
sb.append('"');
sb.append(':');
Object value = jsonObject.get(key);
appendValueAsString(value, sb);
} catch (JSONException ex) {
LOG.log(Level.SEVERE, null, ex);
}
}
}
sb.append('}');
return sb.toString();
}
/**
* Make a JSON text of this JSONObject.For compactness, no whitespace is added. If this would not
* result in a syntactically correct JSON text, then null will be returned instead.
*
* <p>Warning: This method assumes that the data structure is acyclical.
*
* @param jsonObject the jsonObject to be normalized, with an operation for each line.
* @return a printable, displayable, portable, transmittable representation of the object,
* beginning with <code>{</code> <small>(left brace)</small> and ending with <code>}
* </code> <small>(right brace)</small>.
*/
public static String asString(JSONObject jsonObject) {
return JsonOperationNormalizer.asString(jsonObject, Boolean.FALSE);
}
/**
* Make a JSON text of this JSONArray. For compactness, no unnecessary whitespace is added. If it
* is not possible to produce a syntactically correct JSON text then null will be returned
* instead. This could occur if the array contains an invalid number.
*
* <p>Warning: This method assumes that the data structure is acyclical.
*
* @return a printable, displayable, transmittable representation of the array.
*/
static String asString(JSONArray array) {
try {
return '[' + normalizeOperations(array) + ']';
} catch (Exception e) {
LOG.severe(e.getMessage());
}
return null;
}
private static Iterator<String> getSortedIterator(JSONObject jsonObject) {
// have to duplicate set, as the original set is read-only
Set<String> keySet = new HashSet<String>(jsonObject.keySet());
List<String> firstListedKeys = null;
for (String SORTING_SEQUENCE_OF_KEYS1 : SORTING_SEQUENCE_OF_KEYS) {
// do not sort 'name' property
if (keySet.contains(SORTING_SEQUENCE_OF_KEYS1)) {
if (firstListedKeys == null) {
firstListedKeys = new ArrayList<String>(3);
}
firstListedKeys.add(SORTING_SEQUENCE_OF_KEYS1);
keySet.remove(SORTING_SEQUENCE_OF_KEYS1);
}
}
List<String> list = new ArrayList<String>(keySet);
// sort the remaining keys
Collections.sort(list);
// if there are any priority keys
if (firstListedKeys != null) {
// add them at the beginning of the operation list (being a JSONObject)
for (int j = 0; j < firstListedKeys.size(); j++) {
list.add(j, firstListedKeys.get(j));
}
}
return list.iterator();
}
/**
* Make a JSON text of an Object value. If the object has an value.toJSONString() method, then
* that method will be used to produce the JSON text. The method is required to produce a strictly
* conforming text. If the object does not contain a toJSONString method (which is the most common
* case), then a text will be produced by the rules.
*
* <p>Warning: This method assumes that the data structure is acyclical.
*
* @param value The value to be serialized.
* @return a printable, displayable, transmittable representation of the object, beginning with
* <code>{</code> <small>(left brace)</small> and ending with <code>}</code>
* <small>(right brace)</small>.
* @throws JSONException If the value is or contains an invalid number.
*/
private static void appendValueAsString(Object value, StringBuilder sb) {
if (value instanceof JSONObject) {
sb.append(JsonOperationNormalizer.asString((JSONObject) value));
} else if (value instanceof JSONArray) {
sb.append(asString((JSONArray) value));
} else if (value instanceof JSONString) {
sb.append(((JSONString) value).toJSONString());
} else if (value instanceof Number) {
sb.append(numberToString((Number) value));
} else if (value instanceof Boolean) {
sb.append(value.toString());
} else if (value == null || value == JSONObject.NULL) {
sb.append("null");
} else if (value instanceof String) {
quote(((String) value), sb);
} else {
sb.append(value.toString());
}
}
private static StringBuilder quote(String string, StringBuilder sb) {
if (string == null || string.isEmpty()) {
sb.append("\"\"");
return sb;
}
char b;
char c = 0;
String hhhh;
int i;
int len = string.length();
sb.append('"');
for (i = 0; i < len; i += 1) {
b = c;
c = string.charAt(i);
switch (c) {
case '\\':
case '"':
sb.append('\\');
sb.append(c);
break;
case '/':
if (b == '<') {
sb.append('\\');
}
sb.append(c);
break;
case '\b':
sb.append("\\b");
break;
case '\t':
sb.append("\\t");
break;
case '\n':
sb.append("\\n");
break;
case '\f':
sb.append("\\f");
break;
case '\r':
sb.append("\\r");
break;
default:
if (c < ' ' || (c >= '\u0080' && c < '\u00a0') || (c >= '\u2000' && c < '\u2100')) {
sb.append("\\u");
hhhh = Integer.toHexString(c);
sb.append("0000", 0, 4 - hhhh.length());
sb.append(hhhh);
} else {
sb.append(c);
}
}
}
sb.append('"');
return sb;
}
/**
* Produce a string from a Number.
*
* @param number A Number
* @return A String.
* @throws JSONException If n is a non-finite number.
*/
private static String numberToString(Number number) throws JSONException {
if (number == null) {
throw new JSONException("Null pointer");
}
testValidity(number);
// Shave off trailing zeros and decimal point, if possible.
String string = number.toString();
if (string.indexOf('.') > 0 && string.indexOf('e') < 0 && string.indexOf('E') < 0) {
while (string.endsWith("0")) {
string = string.substring(0, string.length() - 1);
}
if (string.endsWith(".")) {
string = string.substring(0, string.length() - 1);
}
}
return string;
}
/**
* Throw an exception if the object is a NaN or infinite number.
*
* @param o The object to test.
* @throws JSONException If o is a non-finite number.
*/
private static void testValidity(Object o) throws JSONException {
if (o != null) {
if (o instanceof Double) {
if (((Double) o).isInfinite() || ((Double) o).isNaN()) {
throw new JSONException("JSON does not allow non-finite numbers.");
}
} else if (o instanceof Float) {
if (((Float) o).isInfinite() || ((Float) o).isNaN()) {
throw new JSONException("JSON does not allow non-finite numbers.");
}
}
}
}
/**
* Make a string from the contents of this JSONArray.
*
* <p>Currently only adjacent style operations are being sorted.
*
* <p>Warning: This method assumes that the data structure is acyclical.
*
* @throws JSONException If the array contains an invalid number.
*/
private static String normalizeOperations(JSONArray array) {
int len = array.length();
StringBuilder sb = new StringBuilder(len);
// we will go through all elements of the array
boolean opsCollected = false;
SortedSet<JSONObject> sameTypOperations = null;
for (int i = 0; i < len; i += 1) {
if (i > 0 && !opsCollected) {
sb.append(',');
}
String lastOperationName = null;
try {
Object o = array.get(i);
if (o instanceof JSONObject) {
JSONObject operation = (JSONObject) o;
if (operation.has(OPK_NAME)) {
String newOperationName = operation.getString(OPK_NAME);
if (lastOperationName == null) {
lastOperationName = newOperationName;
}
if (newOperationName.equals(OP_STYLE) && lastOperationName.equals(newOperationName)) {
// ADD EQUAL OPERATIONS
if (sameTypOperations == null) {
sameTypOperations = new TreeSet<>(new OperationSorter());
}
sameTypOperations.add(operation);
opsCollected = true;
} else {
if (opsCollected) {
// FLUSH SORTED OPERATIONS
for (JSONObject sortedOperation : sameTypOperations) {
appendValueAsString(sortedOperation, sb);
sb.append(',');
}
sameTypOperations.clear();
opsCollected = false;
}
appendValueAsString(operation, sb);
lastOperationName = null;
}
} else {
appendValueAsString(operation, sb);
lastOperationName = null;
}
} else {
appendValueAsString(o, sb);
}
} catch (JSONException ex) {
sb.append("null");
ex.printStackTrace();
}
}
if (opsCollected) {
// FLUSH SORTED OPERATIONS
for (Iterator<JSONObject> iter = sameTypOperations.iterator(); iter.hasNext(); ) {
appendValueAsString(iter.next(), sb);
if (iter.hasNext()) {
sb.append(',');
}
}
}
return sb.toString();
}
static class OperationSorter implements Comparator<JSONObject> {
private static Collator mCollator = null;
public int compare(JSONObject op1, JSONObject op2) {
int returnValue = 0;
if (op1 instanceof JSONObject && op2 instanceof JSONObject) {
try {
String op1Name = op1.getString(OPK_NAME);
String op2Name = op2.getString(OPK_NAME);
if (op1Name.equals(OP_STYLE) && op1Name.equals(op2Name)) {
String uniqueStyleName1 = op1.getString("type") + op1.getString(OPK_STYLE_ID);
String uniqueStyleName2 = op2.getString("type") + op2.getString(OPK_STYLE_ID);
if (mCollator == null) {
mCollator = Collator.getInstance(Locale.US);
}
return mCollator.compare(uniqueStyleName1, uniqueStyleName2);
}
} catch (JSONException ex) {
Logger.getLogger(JsonOperationNormalizer.class.getName()).log(Level.SEVERE, null, ex);
}
}
return returnValue;
}
}
}