org.antlr.runtime.debug
Class DebugTreeAdaptor

java.lang.Object
  extended by org.antlr.runtime.debug.DebugTreeAdaptor
All Implemented Interfaces:
TreeAdaptor

public class DebugTreeAdaptor
extends java.lang.Object
implements TreeAdaptor

A TreeAdaptor proxy that fires debugging events to a DebugEventListener delegate and uses the TreeAdaptor delegate to do the actual work. All AST events are triggered by this adaptor; no code gen changes are needed in generated rules. Debugging events are triggered *after* invoking tree adaptor routines. Trees created with actions in rewrite actions like "-> ^(ADD {foo} {bar})" cannot be tracked as they might not use the adaptor to create foo, bar. The debug listener has to deal with tree node IDs for which it did not see a createNode event. A single node is sufficient even if it represents a whole tree.


Field Summary
protected  TreeAdaptor adaptor
           
protected  DebugEventListener dbg
           
 
Constructor Summary
DebugTreeAdaptor(DebugEventListener dbg, TreeAdaptor adaptor)
           
 
Method Summary
 void addChild(java.lang.Object t, java.lang.Object child)
          Add a child to the tree t.
 void addChild(java.lang.Object t, Token child)
           
 java.lang.Object becomeRoot(java.lang.Object newRoot, java.lang.Object oldRoot)
          If oldRoot is a nil root, just copy or move the children to newRoot.
 java.lang.Object becomeRoot(Token newRoot, java.lang.Object oldRoot)
          Create a node for newRoot make it the root of oldRoot.
 java.lang.Object create(int tokenType, java.lang.String text)
          Create a new node derived from a token, with a new token type.
 java.lang.Object create(int tokenType, Token fromToken)
          Create a new node derived from a token, with a new token type.
 java.lang.Object create(int tokenType, Token fromToken, java.lang.String text)
          Same as create(tokenType,fromToken) except set the text too.
 java.lang.Object create(Token payload)
          Create a tree node from Token object; for CommonTree type trees, then the token just becomes the payload.
 java.lang.Object deleteChild(java.lang.Object t, int i)
          Remove ith child and shift children down from right.
 java.lang.Object dupNode(java.lang.Object treeNode)
          Duplicate a single tree node.
 java.lang.Object dupTree(java.lang.Object tree)
          Duplicate tree recursively, using dupNode() for each node
 java.lang.Object errorNode(TokenStream input, Token start, Token stop, RecognitionException e)
          Return a tree node representing an error.
 java.lang.Object getChild(java.lang.Object t, int i)
          Get a child 0..n-1 node
 int getChildCount(java.lang.Object t)
          How many children? If 0, then this is a leaf node
 int getChildIndex(java.lang.Object t)
          What index is this node in the child list? Range: 0..n-1 If your node type doesn't handle this, it's ok but the tree rewrites in tree parsers need this functionality.
 DebugEventListener getDebugListener()
           
 java.lang.Object getParent(java.lang.Object t)
          Who is the parent node of this node; if null, implies node is root.
 java.lang.String getText(java.lang.Object t)
           
 Token getToken(java.lang.Object t)
          Return the token object from which this node was created.
 int getTokenStartIndex(java.lang.Object t)
          Get the token start index for this subtree; return -1 if no such index
 int getTokenStopIndex(java.lang.Object t)
          Get the token stop index for this subtree; return -1 if no such index
 TreeAdaptor getTreeAdaptor()
           
 int getType(java.lang.Object t)
          For tree parsing, I need to know the token type of a node
 int getUniqueID(java.lang.Object node)
          For identifying trees.
 boolean isNil(java.lang.Object tree)
          Is tree considered a nil node used to make lists of child nodes?
 java.lang.Object nil()
          Return a nil node (an empty but non-null node) that can hold a list of element as the children.
 void replaceChildren(java.lang.Object parent, int startChildIndex, int stopChildIndex, java.lang.Object t)
          Replace from start to stop child index of parent with t, which might be a list.
 java.lang.Object rulePostProcessing(java.lang.Object root)
          Given the root of the subtree created for this rule, post process it to do any simplifications or whatever you want.
 void setChild(java.lang.Object t, int i, java.lang.Object child)
          Set ith child (0..n-1) to t; t must be non-null and non-nil node
 void setChildIndex(java.lang.Object t, int index)
           
 void setDebugListener(DebugEventListener dbg)
           
 void setParent(java.lang.Object t, java.lang.Object parent)
           
 void setText(java.lang.Object t, java.lang.String text)
          Node constructors can set the text of a node
 void setTokenBoundaries(java.lang.Object t, Token startToken, Token stopToken)
          Where are the bounds in the input token stream for this node and all children? Each rule that creates AST nodes will call this method right before returning.
 void setType(java.lang.Object t, int type)
          Node constructors can set the type of a node
protected  void simulateTreeConstruction(java.lang.Object t)
          ^(A B C): emit create A, create B, add child, ...
 
Methods inherited from class java.lang.Object
clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait
 

Field Detail

dbg

protected DebugEventListener dbg

adaptor

protected TreeAdaptor adaptor
Constructor Detail

DebugTreeAdaptor

public DebugTreeAdaptor(DebugEventListener dbg,
                        TreeAdaptor adaptor)
Method Detail

create

public java.lang.Object create(Token payload)
Description copied from interface: TreeAdaptor
Create a tree node from Token object; for CommonTree type trees, then the token just becomes the payload. This is the most common create call. Override if you want another kind of node to be built.

Specified by:
create in interface TreeAdaptor

errorNode

public java.lang.Object errorNode(TokenStream input,
                                  Token start,
                                  Token stop,
                                  RecognitionException e)
Description copied from interface: TreeAdaptor
Return a tree node representing an error. This node records the tokens consumed during error recovery. The start token indicates the input symbol at which the error was detected. The stop token indicates the last symbol consumed during recovery. You must specify the input stream so that the erroneous text can be packaged up in the error node. The exception could be useful to some applications; default implementation stores ptr to it in the CommonErrorNode. This only makes sense during token parsing, not tree parsing. Tree parsing should happen only when parsing and tree construction succeed.

Specified by:
errorNode in interface TreeAdaptor

dupTree

public java.lang.Object dupTree(java.lang.Object tree)
Description copied from interface: TreeAdaptor
Duplicate tree recursively, using dupNode() for each node

Specified by:
dupTree in interface TreeAdaptor

simulateTreeConstruction

protected void simulateTreeConstruction(java.lang.Object t)
^(A B C): emit create A, create B, add child, ...


dupNode

public java.lang.Object dupNode(java.lang.Object treeNode)
Description copied from interface: TreeAdaptor
Duplicate a single tree node. Override if you want another kind of node to be built.

Specified by:
dupNode in interface TreeAdaptor

nil

public java.lang.Object nil()
Description copied from interface: TreeAdaptor
Return a nil node (an empty but non-null node) that can hold a list of element as the children. If you want a flat tree (a list) use "t=adaptor.nil(); t.addChild(x); t.addChild(y);"

Specified by:
nil in interface TreeAdaptor

isNil

public boolean isNil(java.lang.Object tree)
Description copied from interface: TreeAdaptor
Is tree considered a nil node used to make lists of child nodes?

Specified by:
isNil in interface TreeAdaptor

addChild

public void addChild(java.lang.Object t,
                     java.lang.Object child)
Description copied from interface: TreeAdaptor
Add a child to the tree t. If child is a flat tree (a list), make all in list children of t. Warning: if t has no children, but child does and child isNil then you can decide it is ok to move children to t via t.children = child.children; i.e., without copying the array. Just make sure that this is consistent with have the user will build ASTs. Do nothing if t or child is null.

Specified by:
addChild in interface TreeAdaptor

becomeRoot

public java.lang.Object becomeRoot(java.lang.Object newRoot,
                                   java.lang.Object oldRoot)
Description copied from interface: TreeAdaptor
If oldRoot is a nil root, just copy or move the children to newRoot. If not a nil root, make oldRoot a child of newRoot. old=^(nil a b c), new=r yields ^(r a b c) old=^(a b c), new=r yields ^(r ^(a b c)) If newRoot is a nil-rooted single child tree, use the single child as the new root node. old=^(nil a b c), new=^(nil r) yields ^(r a b c) old=^(a b c), new=^(nil r) yields ^(r ^(a b c)) If oldRoot was null, it's ok, just return newRoot (even if isNil). old=null, new=r yields r old=null, new=^(nil r) yields ^(nil r) Return newRoot. Throw an exception if newRoot is not a simple node or nil root with a single child node--it must be a root node. If newRoot is ^(nil x) return x as newRoot. Be advised that it's ok for newRoot to point at oldRoot's children; i.e., you don't have to copy the list. We are constructing these nodes so we should have this control for efficiency.

Specified by:
becomeRoot in interface TreeAdaptor

rulePostProcessing

public java.lang.Object rulePostProcessing(java.lang.Object root)
Description copied from interface: TreeAdaptor
Given the root of the subtree created for this rule, post process it to do any simplifications or whatever you want. A required behavior is to convert ^(nil singleSubtree) to singleSubtree as the setting of start/stop indexes relies on a single non-nil root for non-flat trees. Flat trees such as for lists like "idlist : ID+ ;" are left alone unless there is only one ID. For a list, the start/stop indexes are set in the nil node. This method is executed after all rule tree construction and right before setTokenBoundaries().

Specified by:
rulePostProcessing in interface TreeAdaptor

addChild

public void addChild(java.lang.Object t,
                     Token child)

becomeRoot

public java.lang.Object becomeRoot(Token newRoot,
                                   java.lang.Object oldRoot)
Description copied from interface: TreeAdaptor
Create a node for newRoot make it the root of oldRoot. If oldRoot is a nil root, just copy or move the children to newRoot. If not a nil root, make oldRoot a child of newRoot. Return node created for newRoot. Be advised: when debugging ASTs, the DebugTreeAdaptor manually calls create(Token child) and then plain becomeRoot(node, node) because it needs to trap calls to create, but it can't since it delegates to not inherits from the TreeAdaptor.

Specified by:
becomeRoot in interface TreeAdaptor

create

public java.lang.Object create(int tokenType,
                               Token fromToken)
Description copied from interface: TreeAdaptor
Create a new node derived from a token, with a new token type. This is invoked from an imaginary node ref on right side of a rewrite rule as IMAG[$tokenLabel]. This should invoke createToken(Token).

Specified by:
create in interface TreeAdaptor

create

public java.lang.Object create(int tokenType,
                               Token fromToken,
                               java.lang.String text)
Description copied from interface: TreeAdaptor
Same as create(tokenType,fromToken) except set the text too. This is invoked from an imaginary node ref on right side of a rewrite rule as IMAG[$tokenLabel, "IMAG"]. This should invoke createToken(Token).

Specified by:
create in interface TreeAdaptor

create

public java.lang.Object create(int tokenType,
                               java.lang.String text)
Description copied from interface: TreeAdaptor
Create a new node derived from a token, with a new token type. This is invoked from an imaginary node ref on right side of a rewrite rule as IMAG["IMAG"]. This should invoke createToken(int,String).

Specified by:
create in interface TreeAdaptor

getType

public int getType(java.lang.Object t)
Description copied from interface: TreeAdaptor
For tree parsing, I need to know the token type of a node

Specified by:
getType in interface TreeAdaptor

setType

public void setType(java.lang.Object t,
                    int type)
Description copied from interface: TreeAdaptor
Node constructors can set the type of a node

Specified by:
setType in interface TreeAdaptor

getText

public java.lang.String getText(java.lang.Object t)
Specified by:
getText in interface TreeAdaptor

setText

public void setText(java.lang.Object t,
                    java.lang.String text)
Description copied from interface: TreeAdaptor
Node constructors can set the text of a node

Specified by:
setText in interface TreeAdaptor

getToken

public Token getToken(java.lang.Object t)
Description copied from interface: TreeAdaptor
Return the token object from which this node was created. Currently used only for printing an error message. The error display routine in BaseRecognizer needs to display where the input the error occurred. If your tree of limitation does not store information that can lead you to the token, you can create a token filled with the appropriate information and pass that back. See BaseRecognizer.getErrorMessage().

Specified by:
getToken in interface TreeAdaptor

setTokenBoundaries

public void setTokenBoundaries(java.lang.Object t,
                               Token startToken,
                               Token stopToken)
Description copied from interface: TreeAdaptor
Where are the bounds in the input token stream for this node and all children? Each rule that creates AST nodes will call this method right before returning. Flat trees (i.e., lists) will still usually have a nil root node just to hold the children list. That node would contain the start/stop indexes then.

Specified by:
setTokenBoundaries in interface TreeAdaptor

getTokenStartIndex

public int getTokenStartIndex(java.lang.Object t)
Description copied from interface: TreeAdaptor
Get the token start index for this subtree; return -1 if no such index

Specified by:
getTokenStartIndex in interface TreeAdaptor

getTokenStopIndex

public int getTokenStopIndex(java.lang.Object t)
Description copied from interface: TreeAdaptor
Get the token stop index for this subtree; return -1 if no such index

Specified by:
getTokenStopIndex in interface TreeAdaptor

getChild

public java.lang.Object getChild(java.lang.Object t,
                                 int i)
Description copied from interface: TreeAdaptor
Get a child 0..n-1 node

Specified by:
getChild in interface TreeAdaptor

setChild

public void setChild(java.lang.Object t,
                     int i,
                     java.lang.Object child)
Description copied from interface: TreeAdaptor
Set ith child (0..n-1) to t; t must be non-null and non-nil node

Specified by:
setChild in interface TreeAdaptor

deleteChild

public java.lang.Object deleteChild(java.lang.Object t,
                                    int i)
Description copied from interface: TreeAdaptor
Remove ith child and shift children down from right.

Specified by:
deleteChild in interface TreeAdaptor

getChildCount

public int getChildCount(java.lang.Object t)
Description copied from interface: TreeAdaptor
How many children? If 0, then this is a leaf node

Specified by:
getChildCount in interface TreeAdaptor

getUniqueID

public int getUniqueID(java.lang.Object node)
Description copied from interface: TreeAdaptor
For identifying trees. How to identify nodes so we can say "add node to a prior node"? Even becomeRoot is an issue. Use System.identityHashCode(node) usually.

Specified by:
getUniqueID in interface TreeAdaptor

getParent

public java.lang.Object getParent(java.lang.Object t)
Description copied from interface: TreeAdaptor
Who is the parent node of this node; if null, implies node is root. If your node type doesn't handle this, it's ok but the tree rewrites in tree parsers need this functionality.

Specified by:
getParent in interface TreeAdaptor

getChildIndex

public int getChildIndex(java.lang.Object t)
Description copied from interface: TreeAdaptor
What index is this node in the child list? Range: 0..n-1 If your node type doesn't handle this, it's ok but the tree rewrites in tree parsers need this functionality.

Specified by:
getChildIndex in interface TreeAdaptor

setParent

public void setParent(java.lang.Object t,
                      java.lang.Object parent)
Specified by:
setParent in interface TreeAdaptor

setChildIndex

public void setChildIndex(java.lang.Object t,
                          int index)
Specified by:
setChildIndex in interface TreeAdaptor

replaceChildren

public void replaceChildren(java.lang.Object parent,
                            int startChildIndex,
                            int stopChildIndex,
                            java.lang.Object t)
Description copied from interface: TreeAdaptor
Replace from start to stop child index of parent with t, which might be a list. Number of children may be different after this call. If parent is null, don't do anything; must be at root of overall tree. Can't replace whatever points to the parent externally. Do nothing.

Specified by:
replaceChildren in interface TreeAdaptor

getDebugListener

public DebugEventListener getDebugListener()

setDebugListener

public void setDebugListener(DebugEventListener dbg)

getTreeAdaptor

public TreeAdaptor getTreeAdaptor()


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