src/main/java/org/apache/sling/servlets/get/impl/helpers/JsonResourceWriter.java - sling-org-apache-sling-servlets-get - Git at Google

 /*
  * 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.sling.servlets.get.impl.helpers;

 import java.io.IOException;
 import java.io.InputStream;
 import java.io.Writer;
 import java.text.DateFormat;
 import java.text.SimpleDateFormat;
 import java.util.Arrays;
 import java.util.Calendar;
 import java.util.Iterator;
 import java.util.List;
 import java.util.Locale;
 import java.util.Map;
 import java.util.Set;

 import org.apache.sling.api.resource.Resource;
 import org.apache.sling.api.resource.ResourceUtil;
 import org.apache.sling.api.resource.ValueMap;
 import org.apache.sling.commons.json.JSONArray;
 import org.apache.sling.commons.json.JSONException;
 import org.apache.sling.commons.json.io.JSONWriter;

 /**
  * Dumps JCR Items as JSON data. The dump methods are threadsafe.
  *
  * Dump can be done on the Resource, property or value level.
  *
  */
 public class JsonResourceWriter {

     private static DateFormat calendarFormat;

     private final Set<String> propertyNamesToIgnore;

     /** Used to format date values */
     public static final String ECMA_DATE_FORMAT = "EEE MMM dd yyyy HH:mm:ss 'GMT'Z";

     /** Used to format date values */
     public static final Locale DATE_FORMAT_LOCALE = Locale.US;


     /**
      * Create a JsonItemWriter
      *
      * @param propertyNamesToIgnore if not null, a property having a name from
      *            this set of values is ignored. TODO we should use a filtering
      *            interface to make the selection of which Nodes and Properties
      *            to dump more flexible.
      */
     public JsonResourceWriter(Set<String> propertyNamesToIgnore) {
         this.propertyNamesToIgnore = propertyNamesToIgnore;
     }

     /** Dump given resource in JSON, optionally recursing into its object */
     public void dump(Resource resource, Writer w, int maxRecursionLevels)
             throws JSONException {
         dump(resource, w, maxRecursionLevels, false);
     }

     /**
      * Dump given resource in JSON, optionally recursing into its objects
      * @param tidy if <code>true</code> the json dump is nicely formatted
      */
     public void dump(Resource resource, Writer w, int maxRecursionLevels, boolean tidy)
             throws JSONException {
         JSONWriter jw = new JSONWriter(w);
         jw.setTidy(tidy);
         dump(resource, jw, 0, maxRecursionLevels);
     }


     /** Dump given resource in JSON, optionally recursing into its objects */
     protected void dump(Resource resource, JSONWriter w,
             int currentRecursionLevel, int maxRecursionLevels)
             throws JSONException {

         final ValueMap valueMap = resource.adaptTo(ValueMap.class);

         @SuppressWarnings("unchecked")
         final Map propertyMap = (valueMap != null)
                 ? valueMap
                 : resource.adaptTo(Map.class);

         w.object();

         if (propertyMap == null) {

             // no map available, try string
             final String value = resource.adaptTo(String.class);
             if (value != null) {

                 // single value property or just plain String resource or...
                 w.key(ResourceUtil.getName(resource));
                 w.value(value);

             } else {

                 // Try multi-value "property"
                 final String[] values = resource.adaptTo(String[].class);
                 if (values != null) {
                     w.key(ResourceUtil.getName(resource));
                     w.value(new JSONArray(Arrays.asList(values)));
                 }

             }

         } else {

             @SuppressWarnings("unchecked")
             final Iterator<Map.Entry> props = propertyMap.entrySet().iterator();

             // the node's actual properties
             while (props.hasNext()) {
                 @SuppressWarnings("unchecked")
                 final Map.Entry prop = props.next();

                 if (propertyNamesToIgnore != null
                     && propertyNamesToIgnore.contains(prop.getKey())) {
                     continue;
                 }

                 writeProperty(w, valueMap, prop.getKey().toString(),
                     prop.getValue());
             }
         }

         // the child nodes
         if (recursionLevelActive(currentRecursionLevel, maxRecursionLevels)) {
             final Iterator<Resource> children = ResourceUtil.listChildren(resource);
             while (children.hasNext()) {
                 final Resource n = children.next();
                 dumpSingleResource(n, w, currentRecursionLevel,
                     maxRecursionLevels);
             }
         }

         w.endObject();
     }

     /** Dump only a subset of the resource properties */
     public void dumpProperties(Resource resource, JSONWriter w,
             List<String> properties)
             throws JSONException {

         final ValueMap valueMap = resource.adaptTo(ValueMap.class);

         @SuppressWarnings("unchecked")
         final Map propertyMap = (valueMap != null)
                 ? valueMap
                 : resource.adaptTo(Map.class);

         if (propertyMap == null) {

         	//TODO : not sure if we have to do something in this case ?
         	return;

         }

         @SuppressWarnings("unchecked")
         final Iterator<Map.Entry> props = propertyMap.entrySet().iterator();

         // the node's actual properties
         while (props.hasNext()) {
             @SuppressWarnings("unchecked")
             final Map.Entry prop = props.next();

             if (propertyNamesToIgnore != null
                 && propertyNamesToIgnore.contains(prop.getKey())) {
                 continue;
             }

             if (properties.contains(prop.getKey().toString()))
                 writeProperty(w, valueMap, prop.getKey().toString(),
                               prop.getValue());
         }
     }

     /** Dump only a value in the correct format */
     public void dumpValue(JSONWriter w, Object value)
     throws JSONException {
         if ( value instanceof InputStream ) {
             // input stream is already handled
             w.value(0);
         } else if ( value instanceof Calendar ) {
             w.value(format((Calendar)value));
         } else if ( value instanceof Boolean ) {
             w.value(((Boolean)value).booleanValue());
         } else if ( value instanceof Long ) {
             w.value(((Long)value).longValue());
         } else if ( value instanceof Integer ) {
             w.value(((Integer)value).longValue());
         } else if ( value instanceof Double ) {
             w.value(((Double)value).doubleValue());
         } else {
             w.value(value.toString());
         }
     }

     /** Dump a single node */
     protected void dumpSingleResource(Resource n, JSONWriter w,
             int currentRecursionLevel, int maxRecursionLevels)
             throws JSONException {
         if (recursionLevelActive(currentRecursionLevel, maxRecursionLevels)) {
             w.key(ResourceUtil.getName(n));
             dump(n, w, currentRecursionLevel + 1, maxRecursionLevels);
         }
     }

     /** true if the current recursion level is active */
     protected boolean recursionLevelActive(int currentRecursionLevel,
             int maxRecursionLevels) {
         return maxRecursionLevels < 0
             || currentRecursionLevel < maxRecursionLevels;
     }

     /**
      * Write a single property
      */
     protected void writeProperty(JSONWriter w,
                                  ValueMap valueMap,
                                  String key,
                                  Object value)
     throws JSONException {
         Object[] values = null;
         if (value.getClass().isArray()) {
             values = (Object[])value;
             // write out empty array
             if ( values.length == 0 ) {
                 w.key(key);
                 w.array();
                 w.endArray();
                 return;
             }
         }

         // special handling for binaries: we dump the length and not the data!
         if (value instanceof InputStream
             || (values != null && values[0] instanceof InputStream)) {
             // TODO for now we mark binary properties with an initial colon in
             // their name
             // (colon is not allowed as a JCR property name)
             // in the name, and the value should be the size of the binary data
             w.key(":" + key);
             if (values == null) {
                 writeLength(w, valueMap, -1, key, (InputStream)value);
             } else {
                 w.array();
                 for (int i = 0; i < values.length; i++) {
                     writeLength(w, valueMap, i, key, (InputStream)values[i]);
                 }
                 w.endArray();
             }
             return;
         }
         w.key(key);

         if (!value.getClass().isArray()) {
             dumpValue(w, value);
         } else {
             w.array();
             for (Object v : values) {
                 dumpValue(w, v);
             }
             w.endArray();
         }
     }

     private void writeLength(JSONWriter w,
                              ValueMap   valueMap,
                              int        index,
                              String     key,
                              InputStream stream)
     throws JSONException {
         try {
             stream.close();
         } catch (IOException ignore) {}
         long length = -1;
         if ( valueMap != null ) {
             if ( index == -1 ) {
                 length = valueMap.get(key, length);
             } else {
                 Long[] lengths = valueMap.get(key, Long[].class);
                 if ( lengths != null && lengths.length > index ) {
                     length = lengths[index];
                 }
             }
         }
         w.value(length);
     }


     public static synchronized String format(Calendar date) {
         if (calendarFormat == null) {
             calendarFormat = new SimpleDateFormat(ECMA_DATE_FORMAT, DATE_FORMAT_LOCALE);
         }
         return calendarFormat.format(date.getTime());
     }
 }
	/*
	* 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.sling.servlets.get.impl.helpers;

	import java.io.IOException;
	import java.io.InputStream;
	import java.io.Writer;
	import java.text.DateFormat;
	import java.text.SimpleDateFormat;
	import java.util.Arrays;
	import java.util.Calendar;
	import java.util.Iterator;
	import java.util.List;
	import java.util.Locale;
	import java.util.Map;
	import java.util.Set;

	import org.apache.sling.api.resource.Resource;
	import org.apache.sling.api.resource.ResourceUtil;
	import org.apache.sling.api.resource.ValueMap;
	import org.apache.sling.commons.json.JSONArray;
	import org.apache.sling.commons.json.JSONException;
	import org.apache.sling.commons.json.io.JSONWriter;

	/**
	* Dumps JCR Items as JSON data. The dump methods are threadsafe.
	*
	* Dump can be done on the Resource, property or value level.
	*
	*/
	public class JsonResourceWriter {

	private static DateFormat calendarFormat;

	private final Set<String> propertyNamesToIgnore;

	/** Used to format date values */
	public static final String ECMA_DATE_FORMAT = "EEE MMM dd yyyy HH:mm:ss 'GMT'Z";

	/** Used to format date values */
	public static final Locale DATE_FORMAT_LOCALE = Locale.US;


	/**
	* Create a JsonItemWriter
	*
	* @param propertyNamesToIgnore if not null, a property having a name from
	* this set of values is ignored. TODO we should use a filtering
	* interface to make the selection of which Nodes and Properties
	* to dump more flexible.
	*/
	public JsonResourceWriter(Set<String> propertyNamesToIgnore) {
	this.propertyNamesToIgnore = propertyNamesToIgnore;
	}

	/** Dump given resource in JSON, optionally recursing into its object */
	public void dump(Resource resource, Writer w, int maxRecursionLevels)
	throws JSONException {
	dump(resource, w, maxRecursionLevels, false);
	}

	/**
	* Dump given resource in JSON, optionally recursing into its objects
	* @param tidy if <code>true</code> the json dump is nicely formatted
	*/
	public void dump(Resource resource, Writer w, int maxRecursionLevels, boolean tidy)
	throws JSONException {
	JSONWriter jw = new JSONWriter(w);
	jw.setTidy(tidy);
	dump(resource, jw, 0, maxRecursionLevels);
	}


	/** Dump given resource in JSON, optionally recursing into its objects */
	protected void dump(Resource resource, JSONWriter w,
	int currentRecursionLevel, int maxRecursionLevels)
	throws JSONException {

	final ValueMap valueMap = resource.adaptTo(ValueMap.class);

	@SuppressWarnings("unchecked")
	final Map propertyMap = (valueMap != null)
	? valueMap
	: resource.adaptTo(Map.class);

	w.object();

	if (propertyMap == null) {

	// no map available, try string
	final String value = resource.adaptTo(String.class);
	if (value != null) {

	// single value property or just plain String resource or...
	w.key(ResourceUtil.getName(resource));
	w.value(value);

	} else {

	// Try multi-value "property"
	final String[] values = resource.adaptTo(String[].class);
	if (values != null) {
	w.key(ResourceUtil.getName(resource));
	w.value(new JSONArray(Arrays.asList(values)));
	}

	}

	} else {

	@SuppressWarnings("unchecked")
	final Iterator<Map.Entry> props = propertyMap.entrySet().iterator();

	// the node's actual properties
	while (props.hasNext()) {
	@SuppressWarnings("unchecked")
	final Map.Entry prop = props.next();

	if (propertyNamesToIgnore != null
	&& propertyNamesToIgnore.contains(prop.getKey())) {
	continue;
	}

	writeProperty(w, valueMap, prop.getKey().toString(),
	prop.getValue());
	}
	}

	// the child nodes
	if (recursionLevelActive(currentRecursionLevel, maxRecursionLevels)) {
	final Iterator<Resource> children = ResourceUtil.listChildren(resource);
	while (children.hasNext()) {
	final Resource n = children.next();
	dumpSingleResource(n, w, currentRecursionLevel,
	maxRecursionLevels);
	}
	}

	w.endObject();
	}

	/** Dump only a subset of the resource properties */
	public void dumpProperties(Resource resource, JSONWriter w,
	List<String> properties)
	throws JSONException {

	final ValueMap valueMap = resource.adaptTo(ValueMap.class);

	@SuppressWarnings("unchecked")
	final Map propertyMap = (valueMap != null)
	? valueMap
	: resource.adaptTo(Map.class);

	if (propertyMap == null) {

	//TODO : not sure if we have to do something in this case ?
	return;

	}

	@SuppressWarnings("unchecked")
	final Iterator<Map.Entry> props = propertyMap.entrySet().iterator();

	// the node's actual properties
	while (props.hasNext()) {
	@SuppressWarnings("unchecked")
	final Map.Entry prop = props.next();

	if (propertyNamesToIgnore != null
	&& propertyNamesToIgnore.contains(prop.getKey())) {
	continue;
	}

	if (properties.contains(prop.getKey().toString()))
	writeProperty(w, valueMap, prop.getKey().toString(),
	prop.getValue());
	}
	}

	/** Dump only a value in the correct format */
	public void dumpValue(JSONWriter w, Object value)
	throws JSONException {
	if ( value instanceof InputStream ) {
	// input stream is already handled
	w.value(0);
	} else if ( value instanceof Calendar ) {
	w.value(format((Calendar)value));
	} else if ( value instanceof Boolean ) {
	w.value(((Boolean)value).booleanValue());
	} else if ( value instanceof Long ) {
	w.value(((Long)value).longValue());
	} else if ( value instanceof Integer ) {
	w.value(((Integer)value).longValue());
	} else if ( value instanceof Double ) {
	w.value(((Double)value).doubleValue());
	} else {
	w.value(value.toString());
	}
	}

	/** Dump a single node */
	protected void dumpSingleResource(Resource n, JSONWriter w,
	int currentRecursionLevel, int maxRecursionLevels)
	throws JSONException {
	if (recursionLevelActive(currentRecursionLevel, maxRecursionLevels)) {
	w.key(ResourceUtil.getName(n));
	dump(n, w, currentRecursionLevel + 1, maxRecursionLevels);
	}
	}

	/** true if the current recursion level is active */
	protected boolean recursionLevelActive(int currentRecursionLevel,
	int maxRecursionLevels) {
	return maxRecursionLevels < 0
	\|\| currentRecursionLevel < maxRecursionLevels;
	}

	/**
	* Write a single property
	*/
	protected void writeProperty(JSONWriter w,
	ValueMap valueMap,
	String key,
	Object value)
	throws JSONException {
	Object[] values = null;
	if (value.getClass().isArray()) {
	values = (Object[])value;
	// write out empty array
	if ( values.length == 0 ) {
	w.key(key);
	w.array();
	w.endArray();
	return;
	}
	}

	// special handling for binaries: we dump the length and not the data!
	if (value instanceof InputStream
	\|\| (values != null && values[0] instanceof InputStream)) {
	// TODO for now we mark binary properties with an initial colon in
	// their name
	// (colon is not allowed as a JCR property name)
	// in the name, and the value should be the size of the binary data
	w.key(":" + key);
	if (values == null) {
	writeLength(w, valueMap, -1, key, (InputStream)value);
	} else {
	w.array();
	for (int i = 0; i < values.length; i++) {
	writeLength(w, valueMap, i, key, (InputStream)values[i]);
	}
	w.endArray();
	}
	return;
	}
	w.key(key);

	if (!value.getClass().isArray()) {
	dumpValue(w, value);
	} else {
	w.array();
	for (Object v : values) {
	dumpValue(w, v);
	}
	w.endArray();
	}
	}

	private void writeLength(JSONWriter w,
	ValueMap valueMap,
	int index,
	String key,
	InputStream stream)
	throws JSONException {
	try {
	stream.close();
	} catch (IOException ignore) {}
	long length = -1;
	if ( valueMap != null ) {
	if ( index == -1 ) {
	length = valueMap.get(key, length);
	} else {
	Long[] lengths = valueMap.get(key, Long[].class);
	if ( lengths != null && lengths.length > index ) {
	length = lengths[index];
	}
	}
	}
	w.value(length);
	}


	public static synchronized String format(Calendar date) {
	if (calendarFormat == null) {
	calendarFormat = new SimpleDateFormat(ECMA_DATE_FORMAT, DATE_FORMAT_LOCALE);
	}
	return calendarFormat.format(date.getTime());
	}
	}