Package org.antlr.runtime.tree

Class CommonTreeNodeStream

java.lang.Object
org.antlr.runtime.misc.FastQueue<T>
org.antlr.runtime.misc.LookaheadStream<Object>
org.antlr.runtime.tree.CommonTreeNodeStream
All Implemented Interfaces:
IntStream, TreeNodeStream
public class CommonTreeNodeStream extends LookaheadStream<Object> implements TreeNodeStream

  • Field Details

    • DEFAULT_INITIAL_BUFFER_SIZE

      public static final int DEFAULT_INITIAL_BUFFER_SIZE
      See Also:

    • INITIAL_CALL_STACK_SIZE

      public static final int INITIAL_CALL_STACK_SIZE
      See Also:

    • root

      protected Object root
      Pull nodes from which tree?

    • tokens

      protected TokenStream tokens
      If this tree (root) was created from a token stream, track it.

    • adaptor

      TreeAdaptor adaptor
      What tree adaptor was used to build these trees

    • it

      protected TreeIterator it
      The tree iterator we using

    • calls

      protected IntArray calls
      Stack of indexes used for push/pop calls

    • hasNilRoot

      protected boolean hasNilRoot
      Tree (nil A B C) trees like flat A B C streams

    • level

      protected int level
      Tracks tree depth. Level=0 means we're at root node level.

  • Constructor Details

    • CommonTreeNodeStream

      public CommonTreeNodeStream(Object tree)

    • CommonTreeNodeStream

      public CommonTreeNodeStream(TreeAdaptor adaptor, Object tree)

  • Method Details

    • reset

      public void reset()
      Description copied from interface: TreeNodeStream
      Reset the tree node stream in such a way that it acts like a freshly constructed stream.
      Specified by:
      reset in interface TreeNodeStream
      Overrides:
      reset in class LookaheadStream<Object>

    • nextElement

      public Object nextElement()
      Pull elements from tree iterator. Track tree level 0..max_level. If nil rooted tree, don't give initial nil and DOWN nor final UP.
      Specified by:
      nextElement in class LookaheadStream<Object>

    • setUniqueNavigationNodes

      public void setUniqueNavigationNodes(boolean uniqueNavigationNodes)
      Description copied from interface: TreeNodeStream
      As we flatten the tree, we use UP, 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;
      Specified by:
      setUniqueNavigationNodes in interface TreeNodeStream

    • getTreeSource

      public Object getTreeSource()
      Description copied from interface: TreeNodeStream
      Where is this stream pulling nodes from? This is not the name, but the object that provides node objects.
      Specified by:
      getTreeSource in interface TreeNodeStream

    • getSourceName

      public String getSourceName()
      Description copied from interface: IntStream
      Where are you getting symbols from? Normally, implementations will pass the buck all the way to the lexer who can ask its input stream for the file name or whatever.
      Specified by:
      getSourceName in interface IntStream

    • getTokenStream

      public TokenStream getTokenStream()
      Description copied from interface: TreeNodeStream
      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.
      Specified by:
      getTokenStream in interface TreeNodeStream

    • setTokenStream

      public void setTokenStream(TokenStream tokens)

    • getTreeAdaptor

      public TreeAdaptor getTreeAdaptor()
      Description copied from interface: TreeNodeStream
      What adaptor can tell me how to interpret/navigate nodes and trees. E.g., get text of a node.
      Specified by:
      getTreeAdaptor in interface TreeNodeStream

    • setTreeAdaptor

      public void setTreeAdaptor(TreeAdaptor adaptor)

    • LA

      public int LA(int i)
      Description copied from interface: IntStream
      Get int at current input pointer + i ahead where i=1 is next int. Negative indexes are allowed. LA(-1) is previous token (token just matched). LA(-i) where i is before first token should yield -1, invalid char / EOF.
      Specified by:
      LA in interface IntStream

    • push

      public void push(int index)
      Make stream jump to a new location, saving old location. Switch back with pop().

    • pop

      public int pop()
      Seek back to previous index saved during last push() call. Return top of stack (return index).

    • replaceChildren

      public void replaceChildren(Object parent, int startChildIndex, int stopChildIndex, Object t)
      Description copied from interface: TreeNodeStream
      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. 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.
      Specified by:
      replaceChildren in interface TreeNodeStream

    • toString

      public String toString(Object start, Object stop)
      Description copied from interface: TreeNodeStream
      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.
      Specified by:
      toString in interface TreeNodeStream

    • toTokenTypeString

      public String toTokenTypeString()
      For debugging; destructive: moves tree iterator to end.