use Appendable rather than StringBuffer for toJava()
[sbp.git] / src / edu / berkeley / sbp / Tree.java
index 1f55a90..cce7bfe 100644 (file)
@@ -1,4 +1,4 @@
-// Copyright 2006 all rights reserved; see LICENSE file for BSD-style license
+// Copyright 2006-2007 all rights reserved; see LICENSE file for BSD-style license
 
 package edu.berkeley.sbp;
 import edu.berkeley.sbp.*;
@@ -12,6 +12,8 @@ public class Tree<NodeType>
     extends PrintableTree<Tree<NodeType>>
     implements Iterable<Tree<NodeType>> {
 
+    private static final Tree[] emptyTree = new Tree[0];
+
     private final Input.Region     location;
     private final NodeType         ihead;
     private final Tree<NodeType>[] children;
@@ -35,32 +37,45 @@ public class Tree<NodeType>
     /** get the input region that this tree was parsed from */
     public Input.Region    getRegion() { 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(Input.Region loc, NodeType head) {
+        location = loc;
+        ihead = head;
+        children = emptyTree;
+    }
+    public Tree(Input.Region loc, NodeType head, List<Tree<NodeType>> kids){
+        location = loc;
+        ihead = head;
+        if (kids.size() == 0)
+            children = emptyTree;
+        else {
+            children = new Tree[kids.size()];
+            kids.toArray(children);
+        }
+    }
+    public Tree(Input.Region loc, NodeType head, Tree<NodeType>[] kids) {
+        location = loc;
+        ihead = head;
+        children = (kids == null ? emptyTree : kids.clone());
+    }
 
     // FIXME: fairly inefficient because we keep copying arrays
     /** package-private constructor, allows setting the "lift" bit */
-    Tree(Input.Region loc, NodeType head, Tree<NodeType>[] children, boolean lift) {
-        this(loc, head, children, lift, false);
-    }
-    Tree(Input.Region loc, NodeType head, Tree<NodeType>[] children, boolean lift, boolean liftLeft) {
+    Tree(Input.Region loc, NodeType head, Tree<NodeType>[] children, boolean[] lifts) {
         this.location = loc;
         this.ihead = head;
-        // FIXME: lift+liftLeft togheter
-        if (liftLeft && children != null && children.length > 0) {
-            Tree<NodeType> last = children[0];
-            this.children = new Tree[(children.length-1)+last.children.length];
-            System.arraycopy(children, 1, this.children, last.children.length, children.length-1);
-            if (last.children.length > 0)
-                System.arraycopy(last.children, 0, this.children, 0, last.children.length);
-        } else if (lift && children != null && children.length > 0) {
-            Tree<NodeType> last = children[children.length-1];
-            this.children = new Tree[(children.length-1)+last.children.length];
-            System.arraycopy(children, 0, this.children, 0, children.length-1);
-            if (last.children.length > 0)
-                System.arraycopy(last.children, 0, this.children, children.length-1, last.children.length);
-        } else {
-            this.children = ArrayUtil.clone(children, Tree.class);
+
+        int count = 0;
+        for(int i=0; i<children.length; i++)
+            count += lifts[i] ? children[i].size() : 1;
+
+        this.children = new Tree[count];
+        int j = 0;
+        for(int i=0; i<children.length; i++) {
+            if (!lifts[i])
+                this.children[j++] = children[i];
+            else
+                for(int k=0; k<children[i].size(); k++)
+                    this.children[j++] = children[i].child(k);
         }
     }
 
@@ -73,7 +88,9 @@ public class Tree<NodeType>
         if (head()==null) return null;
         if (head() instanceof ToJava) {
             StringBuffer sb = new StringBuffer();
-            ((ToJava)head()).toJava(sb);
+            try {
+                ((ToJava)head()).toJava(sb);
+            } catch (IOException e) { throw new RuntimeException(e); }
             return sb.toString();
         }
         return (head()==null?"null":("\""+StringUtil.toJavaString(head().toString())+"\""));