[Mulgara-svn] r864 - projects/xa2/object-pool/src

[andrae at mulgara.org]

Author: andrae
Date: 2008-04-28 20:32:48 -0700 (Mon, 28 Apr 2008)
New Revision: 864

Modified:
   projects/xa2/object-pool/src/CompBlockTrie.java
   projects/xa2/object-pool/src/CompMemTrie.java
Log:
Migrated individual node write() code out of the memory-trie and into the block-trie.



Modified: projects/xa2/object-pool/src/CompBlockTrie.java
===================================================================
--- projects/xa2/object-pool/src/CompBlockTrie.java	2008-04-29 03:03:56 UTC (rev 863)
+++ projects/xa2/object-pool/src/CompBlockTrie.java	2008-04-29 03:32:48 UTC (rev 864)
@@ -9,6 +9,7 @@
 import java.nio.ByteOrder;
 import java.nio.channels.FileChannel;
 import java.util.HashMap;
+import java.util.Map;
 
 /**
  * Extends CompMemTrie to guarantee the trie will fit within a single block.
@@ -145,7 +146,7 @@
 
     index.putInt(MAGIC);
     if (root != null) {
-      root.write(index, data);
+      writeTrieNode(root, index, data);
     }
     index.put(TYPE_ROOT_LOC);
     index.put((byte)0xFF);
@@ -156,4 +157,68 @@
     // Reset the limit to its initial value.
     index.limit(limit);
   }
+
+  private static Map<Class, TrieNodeWriter> writerMap = new HashMap<Class, TrieNodeWriter>();
+  static {
+    writerMap.put(TrieBranch.class, new TrieBranchWriter());
+    writerMap.put(TrieLeaf.class, new TrieLeafWriter());
+  }
+
+  protected static void writeTrieNode(TrieNode node, ByteBuffer index, FileChannel data) throws IOException {
+    writerMap.get(node.getClass()).write(node, index, data);
+  }
+
+  private static interface TrieNodeWriter {
+    /**
+     * This method *must* update location with the position in the index buffer it was written to.
+     * This allows parents to obtain a physical reference to this node in their write methods.
+     * The index buffer is the target of the Trie index itself.
+     * The data buffer is the target of the byte[]/value pairs stored in the leaves.  We want to keep these
+     * separate for caching purposes.
+     */
+    public void write(TrieNode node, ByteBuffer index, FileChannel data) throws IOException;
+  }
+
+  private static class TrieBranchWriter implements TrieNodeWriter {
+    public void write(TrieNode node, ByteBuffer index, FileChannel data) throws IOException {
+      TrieBranch branch = (TrieBranch)node;
+      if (branch.term != null) {
+        writeTrieNode(branch.term, index, data);
+      }
+      for (TrieNode child : branch.children) {
+        writeTrieNode(child, index, data);
+      }
+
+      branch.location = (short)index.position();
+      
+      index.put((branch.term == null) ? TYPE_BRANCH_NOTERM : TYPE_BRANCH_TERM);
+      index.put((byte)0xFF);  // Padding to keep things short-aligned.
+      index.putInt(branch.offset);
+      if (branch.term != null) {
+        index.putShort(branch.term.location);
+      }
+      branch.children.writeHeader(index);
+      for (TrieNode child : branch.children) {
+        index.putShort(child.location);
+      }
+    }
+  }
+
+  private static class TrieLeafWriter implements TrieNodeWriter {
+    public void write(TrieNode node, ByteBuffer index, FileChannel data) throws IOException {
+      TrieLeaf leaf = (TrieLeaf)node;
+
+      ByteBuffer dataBuf = ByteBuffer.allocateDirect(8 + 4 + leaf.key.length);
+      leaf.keyLocation = data.position();
+      dataBuf.putLong(leaf.value);
+      dataBuf.putInt(leaf.key.length);
+      dataBuf.put(leaf.key);
+      data.write((ByteBuffer)dataBuf.flip());
+
+      leaf.location = (short)index.position();
+      index.put(TYPE_LEAF);
+      index.put((byte)0xFF); // Pad to 16-bit aligned.
+      index.putLong(leaf.keyLocation);
+    }
+  }
 }

Modified: projects/xa2/object-pool/src/CompMemTrie.java
===================================================================
--- projects/xa2/object-pool/src/CompMemTrie.java	2008-04-29 03:03:56 UTC (rev 863)
+++ projects/xa2/object-pool/src/CompMemTrie.java	2008-04-29 03:32:48 UTC (rev 864)
@@ -83,14 +83,6 @@
       return lookup(key, 0, valid);
     }
 
-    /**
-     * This method *must* update location with the position in the index buffer it was written to.
-     * This allows parents to obtain a physical reference to this node in their write methods.
-     * The index buffer is the target of the Trie index itself.
-     * The data buffer is the target of the byte[]/value pairs stored in the leaves.  We want to keep these
-     * separate for caching purposes.
-     */
-    protected abstract void write(ByteBuffer index, FileChannel data) throws IOException;
     protected abstract int totalIndexSize();
     protected abstract int totalDataSize();
     protected abstract boolean insert(TrieLeaf node, int parentLcd);
@@ -112,9 +104,9 @@
   }
 
   protected static class TrieBranch extends TrieNode {
-    private int offset;
-    private ByteMap<TrieNode> children;
-    private TrieLeaf term;
+    protected int offset;
+    protected ByteMap<TrieNode> children;
+    protected TrieLeaf term;
     
     public TrieBranch(byte[] key, long value) {
       super();
@@ -178,28 +170,6 @@
 //      aLeaf = (term == null) ? ((TrieNode)(children.data[0])).aLeaf : term;
     }
 
-    protected void write(ByteBuffer index, FileChannel data) throws IOException {
-      if (term != null) {
-        term.write(index, data);
-      }
-      for (TrieNode child : children) {
-        child.write(index, data);
-      }
-
-      location = (short)index.position();
-      
-      index.put((term == null) ? TYPE_BRANCH_NOTERM : TYPE_BRANCH_TERM);
-      index.put((byte)0xFF);  // Padding to keep things short-aligned.
-      index.putInt(offset);
-      if (term != null) {
-        index.putShort(term.location);
-      }
-      children.writeHeader(index);
-      for (TrieNode child : children) {
-        index.putShort(child.location);
-      }
-    }
-
     private TrieBranch(TrieNode oldNode, TrieLeaf newNode) {
       super();
       assert oldNode != null;
@@ -314,7 +284,7 @@
     final byte[] key;
     final long value;
 
-    private long keyLocation = 0;
+    protected long keyLocation = 0;
 
     public TrieLeaf(byte[] key, long value) {
       super();
@@ -365,20 +335,6 @@
       return 8 + 4 + key.length;
     }
 
-    protected void write(ByteBuffer index, FileChannel data) throws IOException {
-      ByteBuffer dataBuf = ByteBuffer.allocateDirect(8 + 4 + key.length);
-      keyLocation = data.position();
-      dataBuf.putLong(value);
-      dataBuf.putInt(key.length);
-      dataBuf.put(key);
-      data.write((ByteBuffer)dataBuf.flip());
-
-      location = (short)index.position();
-      index.put(TYPE_LEAF);
-      index.put((byte)0xFF); // Pad to 16-bit aligned.
-      index.putLong(keyLocation);
-    }
-
     public String toString() {
       return "Trie-LEAF: " + Arrays.toString(key) + " -> " + value;
     }