LOTS of changes. Biggies include proper support for relations, including

[cql-java-moved-to-github.git] / src / org / z3950 / zing / cql / CQLNode.java

diff --git a/src/org/z3950/zing/cql/CQLNode.java b/src/org/z3950/zing/cql/CQLNode.java
index b619bbb..3267432 100644 (file)
--- a/src/org/z3950/zing/cql/CQLNode.java
+++ b/src/org/z3950/zing/cql/CQLNode.java
@@ -1,13 +1,13 @@
-// $Id: CQLNode.java,v 1.3 2002-10-25 16:04:44 mike Exp $
+// $Id: CQLNode.java,v 1.7 2002-10-30 09:19:26 mike Exp $
 
 package org.z3950.zing.cql;
 
 
 /**
- * Represents a node in a CQL parse-tree ...
+ * Represents a node in a CQL parse-tree.
  * ###
  *
- * @version    $Id: CQLNode.java,v 1.3 2002-10-25 16:04:44 mike Exp $
+ * @version    $Id: CQLNode.java,v 1.7 2002-10-30 09:19:26 mike Exp $
  */
 public abstract class CQLNode {
     abstract String toXCQL(int level);
@@ -21,11 +21,42 @@ public abstract class CQLNode {
        return x;
     }
 
+    // XML Quote --
+    // s/&/&/g;
+    // s/</&lt;/g;
+    // s/>/&gt;/g;
+    // This is hideously inefficient, but I just don't see a better
+    // way using the standard JAVA library.
+    //
+    protected String xq(String str) {
+       str = replace(str, "&", "&amp;");
+       str = replace(str, "<", "&lt;");
+       str = replace(str, ">", "&gt;");
+       return str;
+    }
+
+    // I can't _believe_ I have to write this by hand in 2002 ...
+    protected static String replace(String str, String from, String to) {
+       StringBuffer sb = new StringBuffer();
+       int ix;                 // index of next `from'
+       int offset = 0;         // index of previous `from' + length(from)
+
+       while ((ix = str.indexOf(from, offset)) != -1) {
+           sb.append(str.substring(offset, ix));
+           sb.append(to);
+           offset = ix + from.length();
+       }
+
+       // End of string: append last bit and we're done
+       sb.append(str.substring(offset));
+       return sb.toString();
+    }
+
     // Test harness
     public static void main (String[] args) {
        CQLNode n1 = new CQLTermNode("dc.author", "=", "kernighan");
        CQLNode n2 = new CQLTermNode("dc.title", "all", "elements style");
        CQLNode root = new CQLAndNode(n1, n2);
-       System.out.println(root.toXCQL(3));
+       System.out.println(root.toXCQL(0));
     }
 }