/* $Id: Configuration.java 988245 2010-08-23 18:39:35Z kwright $ */
/**
* 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.manifoldcf.core.interfaces;
import org.apache.manifoldcf.core.interfaces.*;
import java.util.*;
import java.io.*;
import org.apache.manifoldcf.core.system.ManifoldCF;
import org.apache.manifoldcf.core.common.XMLDoc;
import org.json.simple.JSONArray;
import org.json.simple.JSONObject;
import org.json.simple.parser.JSONParser;
import org.json.simple.parser.ParseException;
/** This class represents XML configuration information, in its most basic incarnation.
*/
public class Configuration implements IHierarchyParent
{
public static final String _rcsid = "@(#)$Id: Configuration.java 988245 2010-08-23 18:39:35Z kwright $";
// JSON special key values
protected static final String JSON_ATTRIBUTE = "_attribute_";
protected static final String JSON_VALUE = "_value_";
protected static final String JSON_CHILDREN = "_children_";
protected static final String JSON_TYPE = "_type_";
// The root node type
protected String rootNodeLabel;
// The children
protected List<ConfigurationNode> children = new ArrayList<ConfigurationNode>();
// Read-only flag
protected boolean readOnly = false;
/** Constructor.
*/
public Configuration()
{
rootNodeLabel = "data";
}
/** Constructor.
*@param rootNodeLabel is the root node label to use.
*/
public Configuration(String rootNodeLabel)
{
this.rootNodeLabel = rootNodeLabel;
}
/** Create a new object of the appropriate class.
*@return the newly-created configuration object.
*/
protected Configuration createNew()
{
return new Configuration();
}
/** Create a new child node of the appropriate type and class.
*@return the newly-created node.
*/
protected ConfigurationNode createNewNode(String type)
{
return new ConfigurationNode(type);
}
/** Note the removal of all outer nodes.
*/
protected void clearOuterNodes()
{
}
/** Note the addition of a new outer node.
*@param node is the node that was just read.
*/
protected void addOuterNode(ConfigurationNode node)
{
}
/** Note the removal of an outer node.
*@param node is the node that was just removed.
*/
protected void removeOuterNode(ConfigurationNode node)
{
}
/** Create a duplicate.
*/
protected Configuration createDuplicate(boolean readOnly)
{
if (readOnly && this.readOnly)
return this;
// Create a new object.
Configuration rval = createNew();
rval.readOnly = readOnly;
// Copy the children.
if (children != null)
{
int i = 0;
while (i < children.size())
{
ConfigurationNode child = children.get(i++);
// Duplicate the child
ConfigurationNode newChild = child.createDuplicate(readOnly);
rval.addChild(rval.getChildCount(),newChild);
}
}
return rval;
}
/** Make the configuration read-only */
public void makeReadOnly()
{
if (readOnly)
return;
if (children != null)
{
int i = 0;
while (i < children.size())
{
ConfigurationNode child = children.get(i++);
child.makeReadOnly();
}
}
readOnly = true;
}
/** Get as XML
*@return the xml corresponding to these Configuration.
*/
public String toXML()
throws ManifoldCFException
{
XMLDoc doc = new XMLDoc();
// name of root node in definition
Object top = doc.createElement(null,rootNodeLabel);
// Now, go through all children
int i = 0;
while (i < children.size())
{
ConfigurationNode node = children.get(i++);
writeNode(doc,top,node);
}
return doc.getXML();
}
/** Get as JSON.
*@return the json corresponding to this Configuration.
*/
public String toJSON()
throws ManifoldCFException
{
JSONWriter writer = new JSONWriter();
writer.startObject();
// We do NOT use the root node label, unlike XML.
// Now, do children. To get the arrays right, we need to glue together all children with the
// same type, which requires us to do an appropriate pass to gather that stuff together.
// Since we also need to maintain order, it is essential that we detect the out-of-order condition
// properly, and use an alternate representation if we should find it.
Map<String,List<ConfigurationNode>> childMap = new HashMap<String,List<ConfigurationNode>>();
List<String> childList = new ArrayList<String>();
String lastChildType = null;
boolean needAlternate = false;
int i = 0;
while (i < getChildCount())
{
ConfigurationNode child = findChild(i++);
String key = child.getType();
List<ConfigurationNode> list = childMap.get(key);
if (list == null)
{
list = new ArrayList<ConfigurationNode>();
childMap.put(key,list);
childList.add(key);
}
else
{
if (!lastChildType.equals(key))
{
needAlternate = true;
break;
}
}
list.add(child);
lastChildType = key;
}
if (needAlternate)
{
// Can't use the array representation. We'll need to start do a _children_ object, and enumerate
// each child. So, the JSON will look like:
// <key>:{_attribute_<attr>:xxx,_children_:[{_type_:<child_key>, ...},{_type_:<child_key_2>, ...}, ...]}
writer.key(JSON_CHILDREN);
writer.startArray();
i = 0;
while (i < getChildCount())
{
ConfigurationNode child = findChild(i++);
writeNode(writer,child,false,true);
}
writer.endArray();
}
else
{
// We can collapse child nodes to arrays and still maintain order.
// The JSON will look like this:
// <key>:{_attribute_<attr>:xxx,<child_key>:[stuff],<child_key_2>:[more_stuff] ...}
int q = 0;
while (q < childList.size())
{
String key = childList.get(q++);
List<ConfigurationNode> list = childMap.get(key);
if (list.size() > 1)
{
// Write it as an array
writer.key(key);
writer.startArray();
i = 0;
while (i < list.size())
{
ConfigurationNode child = list.get(i++);
writeNode(writer,child,false,false);
}
writer.endArray();
}
else
{
// Write it as a singleton
writeNode(writer,list.get(0),true,false);
}
}
}
writer.endObject();
// Convert to a string.
return writer.toString();
}
/** Write a specification node.
*@param doc is the document.
*@param parent is the parent.
*@param node is the node.
*/
protected static void writeNode(XMLDoc doc, Object parent, ConfigurationNode node)
throws ManifoldCFException
{
// Get the type
String type = node.getType();
String value = node.getValue();
Object o = doc.createElement(parent,type);
Iterator iter = node.getAttributes();
while (iter.hasNext())
{
String attribute = (String)iter.next();
String attrValue = node.getAttributeValue(attribute);
// Add to the element
doc.setAttribute(o,attribute,attrValue);
}
if (value != null)
doc.createText(o,value);
// Now, do children
int i = 0;
while (i < node.getChildCount())
{
ConfigurationNode child = node.findChild(i++);
writeNode(doc,o,child);
}
}
/** Write a JSON specification node.
*@param writer is the JSON writer.
*@param node is the node.
*@param writeKey is true if the key needs to be written, false otherwise.
*/
protected static void writeNode(JSONWriter writer, ConfigurationNode node, boolean writeKey, boolean writeSpecialKey)
throws ManifoldCFException
{
// Node types correspond directly to keys. Attributes correspond to "_attribute_<attribute_name>".
// Get the type
if (writeKey)
{
String type = node.getType();
writer.key(type);
}
else if (writeSpecialKey)
{
writer.startObject();
writer.key(JSON_TYPE);
writer.value(node.getType());
}
// Problem: Two ways of handling a naked 'value'. First way is to NOT presume a nested object is needed. Second way is to require a nested
// object. On reconstruction, the right thing will happen, and a naked value will become a node with a value, while an object will become
// a node that has an optional "_value_" key inside it.
String value = node.getValue();
if (value != null && node.getAttributeCount() == 0 && node.getChildCount() == 0)
{
writer.value(value);
}
else
{
if (!writeSpecialKey)
writer.startObject();
if (value != null)
{
writer.key(JSON_VALUE);
writer.value(value);
}
Iterator<String> iter = node.getAttributes();
while (iter.hasNext())
{
String attribute = iter.next();
String attrValue = node.getAttributeValue(attribute);
writer.key(JSON_ATTRIBUTE+attribute);
writer.value(attrValue);
}
// Now, do children. To get the arrays right, we need to glue together all children with the
// same type, which requires us to do an appropriate pass to gather that stuff together.
// Since we also need to maintain order, it is essential that we detect the out-of-order condition
// properly, and use an alternate representation if we should find it.
Map<String,List<ConfigurationNode>> childMap = new HashMap<String,List<ConfigurationNode>>();
List<String> childList = new ArrayList<String>();
String lastChildType = null;
boolean needAlternate = false;
int i = 0;
while (i < node.getChildCount())
{
ConfigurationNode child = node.findChild(i++);
String key = child.getType();
List<ConfigurationNode> list = childMap.get(key);
if (list == null)
{
list = new ArrayList<ConfigurationNode>();
childMap.put(key,list);
childList.add(key);
}
else
{
if (!lastChildType.equals(key))
{
needAlternate = true;
break;
}
}
list.add(child);
lastChildType = key;
}
if (needAlternate)
{
// Can't use the array representation. We'll need to start do a _children_ object, and enumerate
// each child. So, the JSON will look like:
// <key>:{_attribute_<attr>:xxx,_children_:[{_type_:<child_key>, ...},{_type_:<child_key_2>, ...}, ...]}
writer.key(JSON_CHILDREN);
writer.startArray();
i = 0;
while (i < node.getChildCount())
{
ConfigurationNode child = node.findChild(i++);
writeNode(writer,child,false,true);
}
writer.endArray();
}
else
{
// We can collapse child nodes to arrays and still maintain order.
// The JSON will look like this:
// <key>:{_attribute_<attr>:xxx,<child_key>:[stuff],<child_key_2>:[more_stuff] ...}
int q = 0;
while (q < childList.size())
{
String key = childList.get(q++);
List<ConfigurationNode> list = childMap.get(key);
if (list.size() > 1)
{
// Write the key
writer.key(key);
// Write it as an array
writer.startArray();
i = 0;
while (i < list.size())
{
ConfigurationNode child = list.get(i++);
writeNode(writer,child,false,false);
}
writer.endArray();
}
else
{
// Write it as a singleton
writeNode(writer,list.get(0),true,false);
}
}
}
if (!writeSpecialKey)
writer.endObject();
}
if (writeSpecialKey)
writer.endObject();
}
/** Read from XML.
*@param xml is the input XML.
*/
public void fromXML(String xml)
throws ManifoldCFException
{
XMLDoc doc = new XMLDoc(xml);
initializeFromDoc(doc);
}
/** Read from JSON.
*@param json is the input JSON.
*/
public void fromJSON(String json)
throws ManifoldCFException
{
if (readOnly)
throw new IllegalStateException("Attempt to change read-only object");
clearChildren();
final JSONReader object = new JSONReader(json);
object.startObject();
// Convert the object into our configuration
final Iterator<String> iter = object.getKeys();
while (iter.hasNext())
{
final String key = iter.next();
object.valueForKey(key);
if (object.isArray())
{
// Iterate through.
object.startArray();
while (object.nextElement()) {
processObject(key,object);
}
object.endArray();
}
else
processObject(key,object);
}
object.endObject();
}
/** Process a JSON object */
protected void processObject(String key, JSONReader x)
throws ManifoldCFException
{
if (x.isObject())
{
// Nested single object
ConfigurationNode cn = readNode(key,x);
addChild(getChildCount(),cn);
}
else if (x.isNull())
{
// Null object. Don't enter the key.
}
else if (key.equals(JSON_CHILDREN))
{
// Children, as a list of separately enumerated child nodes.
if (!(x.isArray()))
throw new ManifoldCFException("Expected array contents for '"+JSON_CHILDREN+"' node");
x.startArray();
while (x.nextElement()) {
ConfigurationNode nestedCn = readNode((String)null,x);
addChild(getChildCount(),nestedCn);
}
x.endArray();
}
else
{
// It's a string or a number or some scalar value
final String value = x.readValue();
ConfigurationNode cn = createNewNode(key);
cn.setValue(value);
addChild(getChildCount(),cn);
}
}
/** Read a node from a json object */
protected ConfigurationNode readNode(String key, JSONReader object)
throws ManifoldCFException
{
object.startObject();
// Override key if type field is found.
if (object.valueForKey(JSON_TYPE))
{
if (!object.isValue()) {
throw new ManifoldCFException("JSON_TYPE key does not have a string value");
}
key = object.readValue();
}
if (key == null)
throw new ManifoldCFException("No type found for node");
final ConfigurationNode rval = createNewNode(key);
final Iterator<String> iter = object.getKeys();
while (iter.hasNext())
{
final String nestedKey = iter.next();
if (!nestedKey.equals(JSON_TYPE))
{
object.valueForKey(nestedKey);
if (object.isArray())
{
// Iterate through.
object.startArray();
while (object.nextElement()) {
processObject(rval,nestedKey,object);
}
object.endArray();
}
else
processObject(rval,nestedKey,object);
}
}
object.endObject();
return rval;
}
/** Process a JSON object */
protected void processObject(ConfigurationNode cn, String key, JSONReader x)
throws ManifoldCFException
{
if (x.isObject())
{
// Nested single object
ConfigurationNode nestedCn = readNode(key,x);
cn.addChild(cn.getChildCount(),nestedCn);
}
else if (x.isNull())
{
// Null object. Don't enter the key.
}
else
{
// It's a string or a number or some scalar value
String value = x.readValue();
// Is it an attribute, or a value?
if (key.startsWith(JSON_ATTRIBUTE))
{
// Attribute. Set the attribute in the current node.
cn.setAttribute(key.substring(JSON_ATTRIBUTE.length()),value);
}
else if (key.equals(JSON_VALUE))
{
// Value. Set the value in the current node.
cn.setValue(value);
}
else if (key.equals(JSON_CHILDREN))
{
// Children, as a list of separately enumerated child nodes.
if (!(x.isArray()))
throw new ManifoldCFException("Expected array contents for '"+JSON_CHILDREN+"' node");
x.startArray();
while (x.nextElement()) {
ConfigurationNode nestedCn = readNode((String)null,x);
cn.addChild(cn.getChildCount(),nestedCn);
}
x.endArray();
}
else
{
// Something we don't recognize, which can only be a simplified key/value pair.
// Create a child node representing the key/value pair.
ConfigurationNode nestedCn = createNewNode(key);
nestedCn.setValue(value);
cn.addChild(cn.getChildCount(),nestedCn);
}
}
}
/** Read from an XML binary stream.
*@param xmlstream is the input XML stream. Does NOT close the stream.
*/
public void fromXML(InputStream xmlstream)
throws ManifoldCFException
{
XMLDoc doc = new XMLDoc(xmlstream);
initializeFromDoc(doc);
}
protected void initializeFromDoc(XMLDoc doc)
throws ManifoldCFException
{
if (readOnly)
throw new IllegalStateException("Attempt to change read-only object");
clearChildren();
ArrayList list = new ArrayList();
doc.processPath(list, "*", null);
if (list.size() != 1)
{
throw new ManifoldCFException("Bad xml - missing outer '"+rootNodeLabel+"' node - there are "+Integer.toString(list.size())+" nodes");
}
Object parent = list.get(0);
if (!doc.getNodeName(parent).equals(rootNodeLabel))
throw new ManifoldCFException("Bad xml - outer node is not '"+rootNodeLabel+"'");
list.clear();
doc.processPath(list, "*", parent);
// Outer level processing.
int i = 0;
while (i < list.size())
{
Object o = list.get(i++);
ConfigurationNode node = readNode(doc,o);
addChild(getChildCount(),node);
}
}
/** Read a configuration node from XML.
*@param doc is the document.
*@param object is the object.
*@return the specification node.
*/
protected ConfigurationNode readNode(XMLDoc doc, Object object)
throws ManifoldCFException
{
String type = doc.getNodeName(object);
ConfigurationNode rval = createNewNode(type);
String value = doc.getData(object);
rval.setValue(value);
// Do attributes
ArrayList list = doc.getAttributes(object);
int i = 0;
while (i < list.size())
{
String attribute = (String)list.get(i++);
String attrValue = doc.getValue(object,attribute);
rval.setAttribute(attribute,attrValue);
}
// Now, do children
list.clear();
doc.processPath(list,"*",object);
i = 0;
while (i < list.size())
{
Object o = list.get(i);
ConfigurationNode node = readNode(doc,o);
rval.addChild(i++,node);
}
return rval;
}
/** Get child count.
*@return the count.
*/
public int getChildCount()
{
return children.size();
}
/** Get child n.
*@param index is the child number.
*@return the child node.
*/
public ConfigurationNode findChild(int index)
{
return children.get(index);
}
/** Remove child n.
*@param index is the child to remove.
*/
public void removeChild(int index)
{
if (readOnly)
throw new IllegalStateException("Attempt to change read-only object");
ConfigurationNode node = children.remove(index);
removeOuterNode(node);
}
/** Add child at specified position.
*@param index is the position to add the child.
*@param child is the child to add.
*/
public void addChild(int index, ConfigurationNode child)
{
if (readOnly)
throw new IllegalStateException("Attempt to change read-only object");
children.add(index,child);
addOuterNode(child);
}
/** Clear children.
*/
public void clearChildren()
{
if (readOnly)
throw new IllegalStateException("Attempt to change read-only object");
children.clear();
clearOuterNodes();
}
/** Calculate a hash code */
public int hashCode()
{
int rval = 0;
int i = 0;
while (i < children.size())
{
rval += children.get(i++).hashCode();
}
return rval;
}
/** Do a comparison */
public boolean equals(Object o)
{
if (!(o instanceof Configuration))
return false;
Configuration p = (Configuration)o;
if (children.size() != p.children.size())
return false;
int i = 0;
while (i < children.size())
{
if (!children.get(i).equals(p.children.get(i)))
return false;
i++;
}
return true;
}
/** Construct a human-readable string */
public String toString()
{
StringBuilder sb = new StringBuilder();
sb.append("[");
if (children != null)
{
int i = 0;
while (i < children.size())
{
if (i > 0)
sb.append(", ");
ConfigurationNode cn = children.get(i++);
sb.append(cn.toString());
}
}
sb.append("]");
return sb.toString();
}
protected static class JSONWriter {
private final List<JSONObject> objectStack = new ArrayList<>();
private final List<String> keyStack = new ArrayList<>();
private final List<JSONArray> arrayStack = new ArrayList<>();
private JSONObject currentObject = null;
private JSONArray currentArray = null;
private String currentKey = null;
private JSONObject finalObject = null;
private JSONArray finalArray = null;
public JSONWriter() {
}
public void startObject() {
pushState();
currentObject = new JSONObject();
currentKey = null;
currentArray = null;
}
public void key(final String key) {
currentKey = key;
}
public void value(final String value) {
currentObject.put(currentKey, value);
}
public void endObject() {
final JSONObject object = currentObject;
// Pop everything
popState();
// Either an array is active, or an object is active, or nothing is active
if (currentObject != null) {
currentObject.put(currentKey, object);
} else if (currentArray != null) {
currentArray.add(object);
} else {
finalObject = object;
}
}
public void startArray() {
pushState();
currentObject = null;
currentKey = null;
currentArray = new JSONArray();
}
public void endArray() {
final JSONArray array = currentArray;
// Pop everything
popState();
// Either an array is active, or an object is active, or nothing is active
if (currentObject != null) {
currentObject.put(currentKey, array);
} else if (currentArray != null) {
currentArray.add(array);
} else {
finalArray = array;
}
}
public String toString() {
if (finalObject != null) {
return finalObject.toJSONString();
} else if (finalArray != null) {
return finalArray.toJSONString();
} else {
return "";
}
}
protected void pushState() {
objectStack.add(currentObject);
keyStack.add(currentKey);
arrayStack.add(currentArray);
}
protected void popState() {
currentObject = objectStack.remove(objectStack.size()-1);
currentKey = keyStack.remove(keyStack.size()-1);
currentArray = arrayStack.remove(arrayStack.size()-1);
}
}
protected static class JSONReader {
private final List<JSONObject> objectStack = new ArrayList<>();
private final List<Iterator> arrayStack = new ArrayList<>();
private JSONObject currentObject = null;
private Iterator currentArrayIterator = null;
private Object next = null;
public JSONReader(final String json) throws ManifoldCFException {
final JSONParser parser = new JSONParser();
try {
next = parser.parse(new StringReader(json));
} catch (Exception e) {
throw new ManifoldCFException("Bad json: "+e.getMessage(),e);
}
}
public boolean isObject() {
return next != null && (next instanceof JSONObject);
}
public void startObject() {
pushState();
currentObject = (JSONObject)next;
currentArrayIterator = null;
}
public Iterator<String> getKeys() {
return currentObject.keySet().iterator();
}
public boolean valueForKey(final String key) {
next = currentObject.get(key);
return next != null;
}
public void endObject() {
popState();
}
public boolean isArray() {
return next != null && (next instanceof JSONArray);
}
public void startArray() {
pushState();
currentObject = null;
currentArrayIterator = ((JSONArray)next).iterator();
}
public boolean nextElement() {
if (currentArrayIterator.hasNext()) {
next = currentArrayIterator.next();
return true;
}
return false;
}
public void endArray() {
popState();
}
public boolean isNull() {
return next == null;
}
public boolean isValue() {
return next != null && !(next instanceof JSONObject || next instanceof JSONArray);
}
public String readValue() {
return next.toString();
}
protected void pushState() {
objectStack.add(currentObject);
arrayStack.add(currentArrayIterator);
}
protected void popState() {
currentObject = objectStack.remove(objectStack.size()-1);
currentArrayIterator = arrayStack.remove(arrayStack.size()-1);
}
}
}