Initial revision

source/org/apache/commons/jrcs/diff/myers/DiffNode.java

@@ -0,0 +1,57 @@
+package org.apache.commons.jrcs.diff.myers;
+
+/**
+ * <p>Title: </p>
+ * <p>Description: </p>
+ * <p>Copyright: Copyright (c) 2002</p>
+ * <p>Company: </p>
+ * @author not attributable
+ * @version 1.0
+ */
+
+/**
+ * A diffnode in a diffpath.
+ * <p>
+ * A DiffNode and its previous node mark a delta between
+ * two input sequences, that is, two differing subsequences
+ * between (possibly zero length) matching sequences.
+ *
+ * {@link DiffNode DiffNodes} and {@link Snake Snakes} allow for compression
+ * of diffpaths, as each snake is represented by a single {@link Snake Snake}
+ * node and each contiguous series of insertions and deletions is represented
+ * by a single {@link DiffNode DiffNodes}.
+ *
+ * @version $Revision: 1.1 $ $Date: 2003/07/14 12:22:29 $
+ * @author <a href="mailto:juanco@suigeneris.org">Juanco Anez</a>
+ *
+ */
+public final class DiffNode
+    extends PathNode
+{
+    /**
+     * Constructs a DiffNode.
+     * <p>
+     * DiffNodes are compressed. That means that
+     * the path pointed to by the <code>prev</code> parameter
+     * will be followed using {@link PathNode#previousSnake}
+     * until a non-diff node is found.
+     *
+     * @param the position in the original sequence
+     * @param the position in the revised sequence
+     * @param prev the previous node in the path.
+     */
+    public DiffNode(int i, int j, PathNode prev)
+    {
+        super(i, j, (prev == null ? null : prev.previousSnake()) );
+    }
+
+    /**
+     * {@inheritDoc}
+     * @return false, always
+     */
+    public boolean isSnake()
+    {
+        return false;
+    }
+
+}