
org.sejda.sambox.pdmodel.common.PDNumberTreeNode Maven / Gradle / Ivy
/*
* 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.sejda.sambox.pdmodel.common;
import org.sejda.sambox.cos.COSArray;
import org.sejda.sambox.cos.COSArrayList;
import org.sejda.sambox.cos.COSBase;
import org.sejda.sambox.cos.COSDictionary;
import org.sejda.sambox.cos.COSInteger;
import org.sejda.sambox.cos.COSName;
import org.sejda.sambox.cos.COSNull;
import org.sejda.sambox.cos.COSObjectable;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;
import java.io.IOException;
import java.util.ArrayList;
import java.util.Collections;
import java.util.HashMap;
import java.util.List;
import java.util.Map;
import static java.util.Objects.nonNull;
/**
* This class represents a PDF Number tree. See the PDF Reference 1.7 section 7.9.7 for more
* details.
*
* @author Ben Litchfield,
* @author Igor Podolskiy
*/
public class PDNumberTreeNode implements COSObjectable
{
private static final Logger LOG = LoggerFactory.getLogger(PDNumberTreeNode.class);
private final COSDictionary node;
private Class extends COSObjectable> valueType = null;
/**
* Constructor.
*
* @param valueClass The PD Model type of object that is the value.
*/
public PDNumberTreeNode(Class extends COSObjectable> valueClass)
{
node = new COSDictionary();
valueType = valueClass;
}
/**
* Constructor.
*
* @param dict The dictionary that holds the name information.
* @param valueClass The PD Model type of object that is the value.
*/
public PDNumberTreeNode(COSDictionary dict, Class extends COSObjectable> valueClass)
{
node = dict;
valueType = valueClass;
}
/**
* Convert this standard java object to a COS object.
*
* @return The cos object that matches this Java object.
*/
@Override
public COSDictionary getCOSObject()
{
return node;
}
/**
* Return the children of this node. This list will contain PDNumberTreeNode objects.
*
* @return The list of children or null if there are no children.
*/
public List getKids()
{
COSArray kids = node.getDictionaryObject(COSName.KIDS, COSArray.class);
if (nonNull(kids))
{
List pdObjects = new ArrayList<>();
for (int i = 0; i < kids.size(); i++)
{
pdObjects.add(createChildNode((COSDictionary) kids.getObject(i)));
}
return new COSArrayList<>(pdObjects, kids);
}
return null;
}
/**
* Set the children of this number tree.
*
* @param kids The children of this number tree.
*/
public void setKids(List extends PDNumberTreeNode> kids)
{
if (kids != null && !kids.isEmpty())
{
PDNumberTreeNode firstKid = kids.get(0);
PDNumberTreeNode lastKid = kids.get(kids.size() - 1);
Integer lowerLimit = firstKid.getLowerLimit();
this.setLowerLimit(lowerLimit);
Integer upperLimit = lastKid.getUpperLimit();
this.setUpperLimit(upperLimit);
}
else if (node.getDictionaryObject(COSName.NUMS) == null)
{
// Remove limits if there are no kids and no numbers set.
node.removeItem(COSName.LIMITS);
}
node.setItem(COSName.KIDS, COSArrayList.converterToCOSArray(kids));
}
/**
* Returns the value corresponding to an index in the number tree.
*
* @param index The index in the number tree.
* @return The value corresponding to the index.
* @throws IOException If there is a problem creating the values.
*/
public Object getValue(Integer index) throws IOException
{
Map numbers = getNumbers();
if (nonNull(numbers))
{
return numbers.get(index);
}
Object retval = null;
List kids = getKids();
if (nonNull(kids))
{
for (int i = 0; i < kids.size() && retval == null; i++)
{
PDNumberTreeNode childNode = kids.get(i);
if (childNode.getLowerLimit().compareTo(index) <= 0
&& childNode.getUpperLimit().compareTo(index) >= 0)
{
retval = childNode.getValue(index);
}
}
}
else
{
LOG.warn("NumberTreeNode does not have \"nums\" nor \"kids\" objects.");
}
return retval;
}
/**
* This will return a map of numbers. The key will be a java.lang.Integer, the value will depend
* on where this class is being used.
*
* @return A map of COS objects.
* @throws IOException If there is a problem creating the values.
*/
public Map getNumbers() throws IOException
{
Map indices = null;
COSArray numbersArray = node.getDictionaryObject(COSName.NUMS, COSArray.class);
if (nonNull(numbersArray))
{
indices = new HashMap<>();
if (numbersArray.size() % 2 != 0)
{
LOG.warn("Numbers array has odd size: " + numbersArray.size());
}
for (int i = 0; i + 1 < numbersArray.size(); i += 2)
{
COSBase base = numbersArray.getObject(i);
if (!(base instanceof COSInteger key))
{
LOG.error("page labels ignored, index {} should be a number, but is {}", i,
base);
return null;
}
COSBase cosValue = numbersArray.getObject(i + 1);
indices.put(key.intValue(), cosValue == null ? null : convertCOSToPD(cosValue));
}
indices = Collections.unmodifiableMap(indices);
}
return indices;
}
/**
* Method to convert the COS value in the name tree to the PD Model object. The default
* implementation will simply use reflection to create the correct object type. Subclasses can
* do whatever they want.
*
* @param base The COS object to convert.
* @return The converted PD Model object.
* @throws IOException If there is an error during creation.
*/
protected COSObjectable convertCOSToPD(COSBase base) throws IOException
{
try
{
return valueType.getConstructor(base.getClass()).newInstance(base);
}
catch (Throwable t)
{
throw new IOException("Error while trying to create value in number tree", t);
}
}
/**
* Create a child node object.
*
* @param dic The dictionary for the child node object to refer to.
* @return The new child node object.
*/
protected PDNumberTreeNode createChildNode(COSDictionary dic)
{
return new PDNumberTreeNode(dic, valueType);
}
/**
* Set the names of for this node. The keys should be java.lang.String and the values must be a
* COSObjectable. This method will set the appropriate upper and lower limits based on the keys
* in the map.
*
* @param numbers The map of names to objects.
*/
public void setNumbers(Map numbers)
{
if (numbers == null)
{
node.setItem(COSName.NUMS, (COSObjectable) null);
node.setItem(COSName.LIMITS, (COSObjectable) null);
}
else
{
List keys = new ArrayList<>(numbers.keySet());
Collections.sort(keys);
COSArray array = new COSArray();
for (Integer key : keys)
{
array.add(COSInteger.get(key));
COSObjectable obj = numbers.get(key);
array.add(obj == null ? COSNull.NULL : obj);
}
Integer lower = null;
Integer upper = null;
if (!keys.isEmpty())
{
lower = keys.get(0);
upper = keys.get(keys.size() - 1);
}
setUpperLimit(upper);
setLowerLimit(lower);
node.setItem(COSName.NUMS, array);
}
}
/**
* Get the highest value for a key in the name map.
*
* @return The highest value for a key in the map.
*/
public Integer getUpperLimit()
{
COSArray arr = node.getDictionaryObject(COSName.LIMITS, COSArray.class);
if (arr != null && arr.get(1) != null)
{
return arr.getInt(1);
}
return null;
}
/**
* Set the highest value for the key in the map.
*
* @param upper The new highest value for a key in the map.
*/
private void setUpperLimit(Integer upper)
{
COSArray arr = node.getDictionaryObject(COSName.LIMITS, COSArray.class);
if (arr == null)
{
arr = new COSArray();
arr.add(null);
arr.add(null);
node.setItem(COSName.LIMITS, arr);
}
if (upper != null)
{
arr.set(1, COSInteger.get(upper));
}
else
{
arr.set(1, null);
}
}
/**
* Get the lowest value for a key in the name map.
*
* @return The lowest value for a key in the map.
*/
public Integer getLowerLimit()
{
COSArray arr = node.getDictionaryObject(COSName.LIMITS, COSArray.class);
if (arr != null && arr.get(0) != null)
{
return arr.getInt(0);
}
return null;
}
/**
* Set the lowest value for the key in the map.
*
* @param lower The new lowest value for a key in the map.
*/
private void setLowerLimit(Integer lower)
{
COSArray arr = node.getDictionaryObject(COSName.LIMITS, COSArray.class);
if (arr == null)
{
arr = new COSArray();
arr.add(null);
arr.add(null);
node.setItem(COSName.LIMITS, arr);
}
if (lower != null)
{
arr.set(0, COSInteger.get(lower));
}
else
{
arr.set(0, null);
}
}
}
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