+// Copyright 2006 all rights reserved; see LICENSE file for BSD-style license
+
package edu.berkeley.sbp;
import edu.berkeley.sbp.*;
-import edu.berkeley.sbp.*;
import edu.berkeley.sbp.util.*;
+import edu.berkeley.sbp.bind.*;
import java.io.*;
import java.util.*;
import java.lang.reflect.*;
-/** a tree (or node in a tree); see jargon.txt for details */
-public class Tree<T> extends PrintableTree<Tree<T>> implements Iterable<Tree<T>> {
+/** <font color=blue>a tree (or node in a tree); see jargon.txt for details</font> */
+public class Tree<NodeType>
+ extends PrintableTree<Tree<NodeType>>
+ implements Iterable<Tree<NodeType>> {
+
+ private final Input.Region location;
+ private final NodeType ihead;
+ private final Tree<NodeType>[] children;
+ private final boolean lift;
+
+ private Tree<NodeType> lifted() { return children[children.length-1]; }
+
+ /** the number of children the tree has */
+ public int size() {
+ return lift
+ ? (children.length-1)+lifted().size()
+ : children.length;
+ }
+
+ /** the element at the head of the tree */
+ public NodeType head() { return ihead; }
+ public NodeType getHead() { return ihead; }
- final T head;
- Tree<T>[] children;
- final Token.Location location;
+ /** the tree's children */
+ public Iterable<Tree<NodeType>> children() { return this; }
- public T head() { return head; }
- public int numChildren() { return children.length; }
- public Iterable<Tree<T>> children() { return new ArrayIterator(children); }
- public Iterator<Tree<T>> iterator() { return new ArrayIterator(children); }
- public Tree<T> child(int i) { return children[i]; }
+ /** the tree's children */
+ public Iterator<Tree<NodeType>> iterator() {
+ return lift
+ ? new ConcatenateIterator(new ArrayIterator(children, 0, children.length-1),
+ children[children.length-1].iterator())
+ : new ArrayIterator(children);
+ }
+
+ /** get the <tt>i</t>th child */
+ public Tree<NodeType> child(int i) {
+ return lift && i >= children.length-1
+ ? children[children.length-1].child(i-(children.length-1))
+ : children[i];
+ }
+
+ /** get the input region that this tree was parsed from */
+ public Input.Region getRegion() { return location; }
- public Token.Location getLocation() { return location; }
+ public Tree(Input.Region loc, NodeType head) { this(loc, head, null); }
+ public Tree(Input.Region loc, NodeType head, Tree<NodeType>[] children) { this(loc, head, children, false); }
- public Tree(Token.Location loc, T head) { this(loc, head, null); }
- public Tree(Token.Location loc, T head, Tree<T>[] children) {
+ /** package-private constructor, allows setting the "lift" bit */
+ Tree(Input.Region loc, NodeType head, Tree<NodeType>[] children, boolean lift) {
this.location = loc;
- this.head = head;
- Tree<T>[] children2 = children==null ? new Tree[0] : new Tree[children.length];
- if (children != null) System.arraycopy(children, 0, children2, 0, children.length);
- this.children = children2;
+ this.ihead = head;
+ this.lift = lift && children != null && children.length > 0;
+ this.children = ArrayUtil.clone(children, Tree.class);
}
- /** since Tree instances are immutable, we can cache this to make pretty-printing MUCH faster */
- public String toString() {
- if (toString!=null) return toString;
- return toString = super.toString();
+
+ // PrintableTree /////////////////////////////////////////////////////////////////////////////
+
+ protected String headToString() { return head()==null?null:head().toString(); }
+ protected String headToJava() {
+ // FIXME
+ if (head()==null) return null;
+ if (head() instanceof ToJava) {
+ StringBuffer sb = new StringBuffer();
+ ((ToJava)head()).toJava(sb);
+ return sb.toString();
+ }
+ return (head()==null?"null":("\""+StringUtil.toJavaString(head().toString())+"\""));
}
- private String toString = null;
+ protected String left() { return "{"; }
+ protected String right() { return "}"; }
+ protected boolean ignoreSingleton() { return false; }
+
- protected String headToString() { return head==null?null:head.toString(); }
- protected String headToJava() { return head==null?null:StringUtil.toJavaString(head+""); }
}