001/* Generated By:JavaCC: Do not edit this line. JJTSRCPParserState.java Version 7.0.3 */
002package jmri.jmris.srcp.parser;
003
004public class JJTSRCPParserState {
005  private java.util.List<Node> nodes;
006  private java.util.List<Integer> marks;
007
008  private int sp;        // number of nodes on stack
009  private int mk;        // current mark
010  private boolean node_created;
011
012  public JJTSRCPParserState() {
013    nodes = new java.util.ArrayList<Node>();
014    marks = new java.util.ArrayList<Integer>();
015    sp = 0;
016    mk = 0;
017  }
018
019  /* Determines whether the current node was actually closed and
020     pushed.  This should only be called in the final user action of a
021     node scope.  */
022  public boolean nodeCreated() {
023    return node_created;
024  }
025
026  /* Call this to reinitialize the node stack.  It is called
027     automatically by the parser's ReInit() method. */
028  public void reset() {
029    nodes.clear();
030    marks.clear();
031    sp = 0;
032    mk = 0;
033  }
034
035  /* Returns the root node of the AST.  It only makes sense to call
036     this after a successful parse. */
037  public Node rootNode() {
038    return nodes.get(0);
039  }
040
041  /* Pushes a node on to the stack. */
042  public void pushNode(Node n) {
043    nodes.add(n);
044    ++sp;
045  }
046
047  /* Returns the node on the top of the stack, and remove it from the
048     stack.  */
049  public Node popNode() {
050    if (--sp < mk) {
051      mk = marks.remove(marks.size()-1);
052    }
053    return nodes.remove(nodes.size()-1);
054  }
055
056  /* Returns the node currently on the top of the stack. */
057  public Node peekNode() {
058    return nodes.get(nodes.size()-1);
059  }
060
061  /* Returns the number of children on the stack in the current node
062     scope. */
063  public int nodeArity() {
064    return sp - mk;
065  }
066
067
068  public void clearNodeScope(Node n) {
069    while (sp > mk) {
070      popNode();
071    }
072    mk = marks.remove(marks.size()-1);
073  }
074
075
076  public void openNodeScope(Node n) {
077    marks.add(mk);
078    mk = sp;
079    n.jjtOpen();
080  }
081
082
083  /* A definite node is constructed from a specified number of
084     children.  That number of nodes are popped from the stack and
085     made the children of the definite node.  Then the definite node
086     is pushed on to the stack. */
087  public void closeNodeScope(Node n, int num) {
088    mk = marks.remove(marks.size()-1);
089    while (num-- > 0) {
090      Node c = popNode();
091      c.jjtSetParent(n);
092      n.jjtAddChild(c, num);
093    }
094    n.jjtClose();
095    pushNode(n);
096    node_created = true;
097  }
098
099
100  /* A conditional node is constructed if its condition is true.  All
101     the nodes that have been pushed since the node was opened are
102     made children of the conditional node, which is then pushed
103     on to the stack.  If the condition is false the node is not
104     constructed and they are left on the stack. */
105  public void closeNodeScope(Node n, boolean condition) {
106    if (condition) {
107      int a = nodeArity();
108      mk = marks.remove(marks.size()-1);
109      while (a-- > 0) {
110        Node c = popNode();
111        c.jjtSetParent(n);
112        n.jjtAddChild(c, a);
113      }
114      n.jjtClose();
115      pushNode(n);
116      node_created = true;
117    } else {
118      mk = marks.remove(marks.size()-1);
119      node_created = false;
120    }
121  }
122}
123/* JavaCC - OriginalChecksum=4eeb6a99959e7daf6f9ea0b848ff5ab6 (do not edit this line) */