ANTLR 3 Runtime 3.5.3 · org.antlr.runtime.tree.TreeNodeStream

Method Summary

Modifier and Type	Method and Description
public Object	get(int i) Get a tree node at an absolute index `i`; 0..n-1.
public TokenStream	getTokenStream() If the tree associated with this stream was created from a `TokenStream`, you can specify it here.
public TreeAdaptor	getTreeAdaptor() What adaptor can tell me how to interpret/navigate nodes and trees.
public Object	getTreeSource() Where is this stream pulling nodes from?
public Object	LT(int k) Get tree node at current input pointer + `k` ahead where `k==1` is next node.
public void	replaceChildren(Object parent, int startChildIndex, int stopChildIndex, Object t) Replace children of `parent` from index `startChildIndex` to `stopChildIndex` with `t`, which might be a list.
public void	reset() Reset the tree node stream in such a way that it acts like a freshly constructed stream.
public void	setUniqueNavigationNodes(boolean uniqueNavigationNodes) As we flatten the tree, we use `Token#UP`, `Token#DOWN` nodes to represent the tree structure.
public String	toString(Object start, Object stop) Return the text of all nodes from `start` to `stop`, inclusive.

Inherited from org.antlr.runtime.IntStream:: consume getSourceName index LA mark release rewind rewind seek size

Method Detail

get	back to summary
public Object get(int i) Get a tree node at an absolute index `i`; 0..n-1. If you don't want to buffer up nodes, then this method makes no sense for you.

getTokenStream	back to summary
public TokenStream getTokenStream() If the tree associated with this stream was created from a `TokenStream`, you can specify it here. Used to do rule `$text` attribute in tree parser. Optional unless you use tree parser rule `$text` attribute or `output=template` and `rewrite=true` options.

getTreeAdaptor	back to summary
public TreeAdaptor getTreeAdaptor() What adaptor can tell me how to interpret/navigate nodes and trees. E.g., get text of a node.

getTreeSource	back to summary
public Object getTreeSource() Where is this stream pulling nodes from? This is not the name, but the object that provides node objects.

LT back to summary

LT	back to summary
public Object LT(int k) Get tree node at current input pointer + `k` ahead where `k==1` is next node. `k<0` indicates nodes in the past. So `LT(-1)` is previous node, but implementations are not required to provide results for `k < -1`. `LT(0)` is undefined. For `k<=n`, return `null`. Return `null` for `LT(0)` and any index that results in an absolute address that is negative. This is analogous to `TokenStream#LT`, but this returns a tree node instead of a `Token`. Makes code generation identical for both parser and tree grammars.

public Object LT(int k)

Get tree node at current input pointer + k ahead where k==1 is next node. k<0 indicates nodes in the past. So LT(-1) is previous node, but implementations are not required to provide results for k < -1. LT(0) is undefined. For k<=n, return null. Return null for LT(0) and any index that results in an absolute address that is negative.

This is analogous to TokenStream#LT, but this returns a tree node instead of a Token. Makes code generation identical for both parser and tree grammars.

replaceChildren back to summary

replaceChildren	back to summary
public void replaceChildren(Object parent, int startChildIndex, int stopChildIndex, Object t) Replace children of `parent` from index `startChildIndex` to `stopChildIndex` with `t`, which might be a list. Number of children may be different after this call. The stream is notified because it is walking the tree and might need to know you are monkeying with the underlying tree. Also, it might be able to modify the node stream to avoid restreaming for future phases. 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.

public void replaceChildren(Object parent, int startChildIndex, int stopChildIndex, Object t)

Replace children of parent from index startChildIndex to stopChildIndex with t, which might be a list. Number of children may be different after this call. The stream is notified because it is walking the tree and might need to know you are monkeying with the underlying tree. Also, it might be able to modify the node stream to avoid restreaming for future phases.

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.

reset	back to summary
public void reset() Reset the tree node stream in such a way that it acts like a freshly constructed stream.

setUniqueNavigationNodes	back to summary
public void setUniqueNavigationNodes(boolean uniqueNavigationNodes) As we flatten the tree, we use `Token#UP`, `Token#DOWN` nodes to represent the tree structure. When debugging we need unique nodes so we have to instantiate new ones. When doing normal tree parsing, it's slow and a waste of memory to create unique navigation nodes. Default should be `false`.

toString	back to summary
public String toString(Object start, Object stop) Return the text of all nodes from `start` to `stop`, inclusive. If the stream does not buffer all the nodes then it can still walk recursively from start until stop. You can always return `null` or `""` too, but users should not access `$ruleLabel.text` in an action of course in that case.

public Interface TreeNodeStream

Method Summary

Method Detail