NodeCollection

Inheritance: java.lang.Object

All Implemented Interfaces: java.lang.Iterable

public class NodeCollection implements Iterable

Represents a collection of nodes of a specific type.

To learn more, visit the Aspose.Words Document Object Model (DOM) documentation article.

Remarks:

NodeCollection does not own the nodes it contains, rather, is just a selection of nodes of the specified type, but the nodes are stored in the tree under their respective parent nodes.

NodeCollection supports indexed access, iteration and provides add and remove methods.

The NodeCollection collection is “live”, i.e. changes to the children of the node object that it was created from are immediately reflected in the nodes returned by the NodeCollection properties and methods.

NodeCollection is returned by M:Aspose.Words.CompositeNode.GetChildNodes(Aspose.Words.NodeType,System.Boolean) and also serves as a base class for typed node collections such as SectionCollection, ParagraphCollection etc.

NodeCollection can be “flat” and contain only immediate children of the node it was created from, or it can be “deep” and contain all descendant children.

Examples:

Shows how to replace all textbox shapes with image shapes.


 Document doc = new Document(getMyDir() + "Textboxes in drawing canvas.docx");

 List shapeList = Arrays.stream(doc.getChildNodes(NodeType.SHAPE, true).toArray())
         .filter(Shape.class::isInstance)
         .map(Shape.class::cast)
         .collect(Collectors.toList());

 Assert.assertEquals(3, IterableUtils.countMatches(shapeList, s -> s.getShapeType() == ShapeType.TEXT_BOX));
 Assert.assertEquals(1, IterableUtils.countMatches(shapeList, s -> s.getShapeType() == ShapeType.IMAGE));

 for (Shape shape : shapeList) {
     if (((shape.getShapeType()) == (ShapeType.TEXT_BOX))) {
         Shape replacementShape = new Shape(doc, ShapeType.IMAGE);
         replacementShape.getImageData().setImage(getImageDir() + "Logo.jpg");
         replacementShape.setLeft(shape.getLeft());
         replacementShape.setTop(shape.getTop());
         replacementShape.setWidth(shape.getWidth());
         replacementShape.setHeight(shape.getHeight());
         replacementShape.setRelativeHorizontalPosition(shape.getRelativeHorizontalPosition());
         replacementShape.setRelativeVerticalPosition(shape.getRelativeVerticalPosition());
         replacementShape.setHorizontalAlignment(shape.getHorizontalAlignment());
         replacementShape.setVerticalAlignment(shape.getVerticalAlignment());
         replacementShape.setWrapType(shape.getWrapType());
         replacementShape.setWrapSide(shape.getWrapSide());

         shape.getParentNode().insertAfter(replacementShape, shape);
         shape.remove();
     }
 }

 shapeList = Arrays.stream(doc.getChildNodes(NodeType.SHAPE, true).toArray())
         .filter(Shape.class::isInstance)
         .map(Shape.class::cast)
         .collect(Collectors.toList());

 Assert.assertEquals(0, IterableUtils.countMatches(shapeList, s -> s.getShapeType() == ShapeType.TEXT_BOX));
 Assert.assertEquals(4, IterableUtils.countMatches(shapeList, s -> s.getShapeType() == ShapeType.IMAGE));

 doc.save(getArtifactsDir() + "Shape.ReplaceTextboxesWithImages.docx");

Methods

Method	Description
add(Node node)	Adds a node to the end of the collection.
clear()	Removes all nodes from this collection and from the document.
contains(Node node)	Determines whether a node is in the collection.
get(int index)	Retrieves a node at the given index.
getContainer()
getCount()	Gets the number of nodes in the collection.
getCurrentNode()
getNextMatchingNode(Node curNode)
indexOf(Node node)	Returns the zero-based index of the specified node.
insert(int index, Node node)	Inserts a node into the collection at the specified index.
iterator()	Provides a simple “foreach” style iteration over the collection of nodes.
remove(Node node)	Removes the node from the collection and from the document.
removeAt(int index)	Removes the node at the specified index from the collection and from the document.
toArray()	Copies all nodes from the collection to a new array of nodes.

add(Node node)

public void add(Node node)

Adds a node to the end of the collection.

Parameters:

Parameter	Type	Description
node	Node	The node to be added to the end of the collection.

clear()

public void clear()

Removes all nodes from this collection and from the document.

Examples:

Shows how to remove all sections from a document.


 Document doc = new Document(getMyDir() + "Document.docx");

 // This document has one section with a few child nodes containing and displaying all the document's contents.
 Assert.assertEquals(doc.getSections().getCount(), 1);
 Assert.assertEquals(doc.getSections().get(0).getChildNodes(NodeType.ANY, true).getCount(), 17);
 Assert.assertEquals("Hello World!\r\rHello Word!\r\r\rHello World!", doc.getText().trim());

 // Clear the collection of sections, which will remove all of the document's children.
 doc.getSections().clear();

 Assert.assertEquals(0, doc.getChildNodes(NodeType.ANY, true).getCount());
 Assert.assertEquals("", doc.getText().trim());

contains(Node node)

public boolean contains(Node node)

Determines whether a node is in the collection.

Remarks:

This method performs a linear search; therefore, the average execution time is proportional to getCount().

Examples:

Shows how to work with a NodeCollection.


 Document doc = new Document();
 DocumentBuilder builder = new DocumentBuilder(doc);

 // Add text to the document by inserting Runs using a DocumentBuilder.
 builder.write("Run 1. ");
 builder.write("Run 2. ");

 // Every invocation of the "Write()" method creates a new Run,
 // which then appears in the parent Paragraph's RunCollection.
 RunCollection runs = doc.getFirstSection().getBody().getFirstParagraph().getRuns();

 Assert.assertEquals(2, runs.getCount());

 // We can also insert a node into the RunCollection manually.
 Run newRun = new Run(doc, "Run 3. ");
 runs.insert(3, newRun);

 Assert.assertTrue(runs.contains(newRun));
 Assert.assertEquals("Run 1. Run 2. Run 3.", doc.getText().trim());

 // Access individual runs and remove them to remove their text from the document.
 Run run = runs.get(1);
 runs.remove(run);

 Assert.assertEquals("Run 1. Run 3.", doc.getText().trim());
 Assert.assertNotNull(run);
 Assert.assertFalse(runs.contains(run));

Parameters:

Parameter	Type	Description
node	Node	The node to locate.

Returns: boolean - true if item is found in the collection; otherwise, false .

get(int index)

public Node get(int index)

Retrieves a node at the given index.

Remarks:

The index is zero-based.

Negative indexes are allowed and indicate access from the back of the collection. For example -1 means the last item, -2 means the second before last and so on.

If index is greater than or equal to the number of items in the list, this returns a null reference.

If index is negative and its absolute value is greater than the number of items in the list, this returns a null reference.

Examples:

Shows how to traverse through a composite node’s collection of child nodes.


 Document doc = new Document();

 // Add two runs and one shape as child nodes to the first paragraph of this document.
 Paragraph paragraph = (Paragraph) doc.getChild(NodeType.PARAGRAPH, 0, true);
 paragraph.appendChild(new Run(doc, "Hello world! "));

 Shape shape = new Shape(doc, ShapeType.RECTANGLE);
 shape.setWidth(200.0);
 shape.setHeight(200.0);
 // Note that the 'CustomNodeId' is not saved to an output file and exists only during the node lifetime.
 shape.setCustomNodeId(100);
 shape.setWrapType(WrapType.INLINE);
 paragraph.appendChild(shape);

 paragraph.appendChild(new Run(doc, "Hello again!"));

 // Iterate through the paragraph's collection of immediate children,
 // and print any runs or shapes that we find within.
 NodeCollection children = paragraph.getChildNodes(NodeType.ANY, false);

 Assert.assertEquals(3, paragraph.getChildNodes(NodeType.ANY, false).getCount());

 for (Node child : (Iterable) children)
     switch (child.getNodeType()) {
         case NodeType.RUN:
             System.out.println("Run contents:");
             System.out.println(MessageFormat.format("\t\"{0}\"", child.getText().trim()));
             break;
         case NodeType.SHAPE:
             Shape childShape = (Shape)child;
             System.out.println("Shape:");
             System.out.println(MessageFormat.format("\t{0}, {1}x{2}", childShape.getShapeType(), childShape.getWidth(), childShape.getHeight()));
             break;
     }

Parameters:

Parameter	Type	Description
index	int	An index into the collection of nodes.

Returns: Node - The corresponding Node value.

getContainer()

public CompositeNode getContainer()

Returns: CompositeNode

getCount()

public int getCount()

Gets the number of nodes in the collection.

Examples:

Shows how to traverse through a composite node’s collection of child nodes.


 Document doc = new Document();

 // Add two runs and one shape as child nodes to the first paragraph of this document.
 Paragraph paragraph = (Paragraph) doc.getChild(NodeType.PARAGRAPH, 0, true);
 paragraph.appendChild(new Run(doc, "Hello world! "));

 Shape shape = new Shape(doc, ShapeType.RECTANGLE);
 shape.setWidth(200.0);
 shape.setHeight(200.0);
 // Note that the 'CustomNodeId' is not saved to an output file and exists only during the node lifetime.
 shape.setCustomNodeId(100);
 shape.setWrapType(WrapType.INLINE);
 paragraph.appendChild(shape);

 paragraph.appendChild(new Run(doc, "Hello again!"));

 // Iterate through the paragraph's collection of immediate children,
 // and print any runs or shapes that we find within.
 NodeCollection children = paragraph.getChildNodes(NodeType.ANY, false);

 Assert.assertEquals(3, paragraph.getChildNodes(NodeType.ANY, false).getCount());

 for (Node child : (Iterable) children)
     switch (child.getNodeType()) {
         case NodeType.RUN:
             System.out.println("Run contents:");
             System.out.println(MessageFormat.format("\t\"{0}\"", child.getText().trim()));
             break;
         case NodeType.SHAPE:
             Shape childShape = (Shape)child;
             System.out.println("Shape:");
             System.out.println(MessageFormat.format("\t{0}, {1}x{2}", childShape.getShapeType(), childShape.getWidth(), childShape.getHeight()));
             break;
     }

Shows how to find out if a tables are nested.


 public void calculateDepthOfNestedTables() throws Exception {
     Document doc = new Document(getMyDir() + "Nested tables.docx");
     NodeCollection tables = doc.getChildNodes(NodeType.TABLE, true);
     for (int i = 0; i < tables.getCount(); i++) {
         Table table = (Table) tables.get(i);

         // Find out if any cells in the table have other tables as children.
         int count = getChildTableCount(table);
         System.out.print(MessageFormat.format("Table #{0} has {1} tables directly within its cells", i, count));

         // Find out if the table is nested inside another table, and, if so, at what depth.
         int tableDepth = getNestedDepthOfTable(table);

         if (tableDepth > 0)
             System.out.println(MessageFormat.format("Table #{0} is nested inside another table at depth of {1}", i, tableDepth));
         else
             System.out.println(MessageFormat.format("Table #{0} is a non nested table (is not a child of another table)", i));
     }
 }

 // Calculates what level a table is nested inside other tables.
 //
 // Returns An integer containing the level the table is nested at.
 // 0 = Table is not nested inside any other table
 // 1 = Table is nested within one parent table
 // 2 = Table is nested within two parent tables etc..
 private static int getNestedDepthOfTable(final Table table) {
     int depth = 0;
     Node parent = table.getAncestor(table.getNodeType());

     while (parent != null) {
         depth++;
         parent = parent.getAncestor(Table.class);
     }

     return depth;
 }

 // Determines if a table contains any immediate child table within its cells.
 // Does not recursively traverse through those tables to check for further tables.
 //
 // Returns true if at least one child cell contains a table.
 // Returns false if no cells in the table contains a table.
 private static int getChildTableCount(final Table table) {
     int childTableCount = 0;

     for (Row row : table.getRows()) {
         for (Cell cell : row.getCells()) {
             TableCollection childTables = cell.getTables();

             if (childTables.getCount() > 0) childTableCount++;
         }
     }

     return childTableCount;
 }

Returns: int - The number of nodes in the collection.

getCurrentNode()

public Node getCurrentNode()

Returns: Node

getNextMatchingNode(Node curNode)

public Node getNextMatchingNode(Node curNode)

Parameters:

Parameter	Type	Description
curNode	Node

Returns: Node

indexOf(Node node)

public int indexOf(Node node)

Returns the zero-based index of the specified node.

Remarks:

This method performs a linear search; therefore, the average execution time is proportional to getCount().

Examples:

Shows how to get the index of a node in a collection.


 Document doc = new Document(getMyDir() + "Tables.docx");

 Table table = doc.getFirstSection().getBody().getTables().get(0);
 NodeCollection allTables = doc.getChildNodes(NodeType.TABLE, true);

 Assert.assertEquals(0, allTables.indexOf(table));

 Row row = table.getRows().get(2);

 Assert.assertEquals(2, table.indexOf(row));

 Cell cell = row.getLastCell();

 Assert.assertEquals(4, row.indexOf(cell));

Parameters:

Parameter	Type	Description
node	Node	The node to locate.

Returns: int - The zero-based index of the node within the collection, if found; otherwise, -1.

insert(int index, Node node)

public void insert(int index, Node node)

Inserts a node into the collection at the specified index.

Parameters:

Parameter	Type	Description
index	int	The zero-based index of the node. Negative indexes are allowed and indicate access from the back of the list. For example -1 means the last node, -2 means the second before last and so on.
node	Node	The node to insert.

iterator()

public Iterator iterator()

Provides a simple “foreach” style iteration over the collection of nodes.

Returns: java.util.Iterator - An Iterator.

remove(Node node)

public void remove(Node node)

Removes the node from the collection and from the document.

Examples:

Shows how to work with a NodeCollection.


 Document doc = new Document();
 DocumentBuilder builder = new DocumentBuilder(doc);

 // Add text to the document by inserting Runs using a DocumentBuilder.
 builder.write("Run 1. ");
 builder.write("Run 2. ");

 // Every invocation of the "Write()" method creates a new Run,
 // which then appears in the parent Paragraph's RunCollection.
 RunCollection runs = doc.getFirstSection().getBody().getFirstParagraph().getRuns();

 Assert.assertEquals(2, runs.getCount());

 // We can also insert a node into the RunCollection manually.
 Run newRun = new Run(doc, "Run 3. ");
 runs.insert(3, newRun);

 Assert.assertTrue(runs.contains(newRun));
 Assert.assertEquals("Run 1. Run 2. Run 3.", doc.getText().trim());

 // Access individual runs and remove them to remove their text from the document.
 Run run = runs.get(1);
 runs.remove(run);

 Assert.assertEquals("Run 1. Run 3.", doc.getText().trim());
 Assert.assertNotNull(run);
 Assert.assertFalse(runs.contains(run));

Parameters:

Parameter	Type	Description
node	Node	The node to remove.

removeAt(int index)

public void removeAt(int index)

Removes the node at the specified index from the collection and from the document.

Examples:

Shows how to add and remove sections in a document.


 Document doc = new Document();
 DocumentBuilder builder = new DocumentBuilder(doc);

 builder.write("Section 1");
 builder.insertBreak(BreakType.SECTION_BREAK_NEW_PAGE);
 builder.write("Section 2");

 Assert.assertEquals("Section 1\fSection 2", doc.getText().trim());

 // Delete the first section from the document.
 doc.getSections().removeAt(0);

 Assert.assertEquals("Section 2", doc.getText().trim());

 // Append a copy of what is now the first section to the end of the document.
 int lastSectionIdx = doc.getSections().getCount() - 1;
 Section newSection = doc.getSections().get(lastSectionIdx).deepClone();
 doc.getSections().add(newSection);

 Assert.assertEquals("Section 2\fSection 2", doc.getText().trim());

Parameters:

Parameter	Type	Description
index	int	The zero-based index of the node. Negative indexes are allowed and indicate access from the back of the list. For example -1 means the last node, -2 means the second before last and so on.

toArray()

public Node[] toArray()

Copies all nodes from the collection to a new array of nodes.

Remarks:

You should not be adding/removing nodes while iterating over a collection of nodes because it invalidates the iterator and requires refreshes for live collections.

To be able to add/remove nodes during iteration, use this method to copy nodes into a fixed-size array and then iterate over the array.

Examples:

Shows how to replace all textbox shapes with image shapes.


 Document doc = new Document(getMyDir() + "Textboxes in drawing canvas.docx");

 List shapeList = Arrays.stream(doc.getChildNodes(NodeType.SHAPE, true).toArray())
         .filter(Shape.class::isInstance)
         .map(Shape.class::cast)
         .collect(Collectors.toList());

 Assert.assertEquals(3, IterableUtils.countMatches(shapeList, s -> s.getShapeType() == ShapeType.TEXT_BOX));
 Assert.assertEquals(1, IterableUtils.countMatches(shapeList, s -> s.getShapeType() == ShapeType.IMAGE));

 for (Shape shape : shapeList) {
     if (((shape.getShapeType()) == (ShapeType.TEXT_BOX))) {
         Shape replacementShape = new Shape(doc, ShapeType.IMAGE);
         replacementShape.getImageData().setImage(getImageDir() + "Logo.jpg");
         replacementShape.setLeft(shape.getLeft());
         replacementShape.setTop(shape.getTop());
         replacementShape.setWidth(shape.getWidth());
         replacementShape.setHeight(shape.getHeight());
         replacementShape.setRelativeHorizontalPosition(shape.getRelativeHorizontalPosition());
         replacementShape.setRelativeVerticalPosition(shape.getRelativeVerticalPosition());
         replacementShape.setHorizontalAlignment(shape.getHorizontalAlignment());
         replacementShape.setVerticalAlignment(shape.getVerticalAlignment());
         replacementShape.setWrapType(shape.getWrapType());
         replacementShape.setWrapSide(shape.getWrapSide());

         shape.getParentNode().insertAfter(replacementShape, shape);
         shape.remove();
     }
 }

 shapeList = Arrays.stream(doc.getChildNodes(NodeType.SHAPE, true).toArray())
         .filter(Shape.class::isInstance)
         .map(Shape.class::cast)
         .collect(Collectors.toList());

 Assert.assertEquals(0, IterableUtils.countMatches(shapeList, s -> s.getShapeType() == ShapeType.TEXT_BOX));
 Assert.assertEquals(4, IterableUtils.countMatches(shapeList, s -> s.getShapeType() == ShapeType.IMAGE));

 doc.save(getArtifactsDir() + "Shape.ReplaceTextboxesWithImages.docx");

Returns: com.aspose.words.Node[] - An array of nodes.

NodeChangingArgs NodeImporter