TransformHierarchy (Apache Beam SDK 0.2.0-incubating API)

```
public class TransformHierarchy
extends Object
```
Captures information about a collection of transformations and their associated PValues.

Constructors
Constructor and Description
`TransformHierarchy()` Create a `TransformHierarchy` containing a root node.

All Methods Instance Methods Concrete Methods
Modifier and Type	Method and Description
`void`	`addInput(TransformTreeNode node, PInput input)` Adds an input to the given node.
`TransformTreeNode`	`getCurrent()` Returns the last TransformTreeNode on the stack.
`void`	`popNode()` Removes the last TransformTreeNode from the stack.
`void`	`pushNode(TransformTreeNode current)` Add a TransformTreeNode to the stack.
`void`	`setOutput(TransformTreeNode producer, POutput output)` Sets the output of a transform node.
`void`	`visit(Pipeline.PipelineVisitor visitor, Set<PValue> visitedNodes)` Visits all nodes in the transform hierarchy, in transitive order.

getCurrent
```
public TransformTreeNode getCurrent()
```
Returns the last TransformTreeNode on the stack.

public void pushNode(TransformTreeNode current)

Add a TransformTreeNode to the stack.

popNode
```
public void popNode()
```
Removes the last TransformTreeNode from the stack.

public void addInput(TransformTreeNode node,
                     PInput input)

Adds an input to the given node.

This forces the producing node to be finished.

public void setOutput(TransformTreeNode producer,
                      POutput output)

Sets the output of a transform node.

public void visit(Pipeline.PipelineVisitor visitor,
                  Set<PValue> visitedNodes)

Visits all nodes in the transform hierarchy, in transitive order.

Class TransformHierarchy