Handle relations, improve XML rendering (wow, was that hard.

[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 baa6cad..3d16a37 100644 (file)
--- a/src/org/z3950/zing/cql/CQLNode.java
+++ b/src/org/z3950/zing/cql/CQLNode.java
@@ -1,4 +1,4 @@
-// $Id: CQLNode.java,v 1.5 2002-10-27 00:46:25 mike Exp $
+// $Id: CQLNode.java,v 1.6 2002-10-29 10:15:58 mike Exp $
 
 package org.z3950.zing.cql;
 
@@ -7,7 +7,7 @@ package org.z3950.zing.cql;
  * Represents a node in a CQL parse-tree ...
  * ###
  *
- * @version    $Id: CQLNode.java,v 1.5 2002-10-27 00:46:25 mike Exp $
+ * @version    $Id: CQLNode.java,v 1.6 2002-10-29 10:15:58 mike Exp $
  */
 public abstract class CQLNode {
     abstract String toXCQL(int level);
@@ -21,14 +21,36 @@ 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) {
-       // XML Quote
-       // ###  s/&/&amp;/g;
-       //      s/</&lt;/g;
-       //      s/>/&gt;/g;
+       str = replace(str, "&", "&amp;");
+       str = replace(str, "<", "&lt;");
+       str = replace(str, ">", "&gt;");
        return str;
     }
 
+    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");