jvanzyl 00/11/27 16:55:43
Modified: src/java/org/apache/velocity/runtime/parser/node
NodeUtils.java
Log:
- Adding method for simple string interpolation. This is borrowed
from the old Torque code. It simply handles the "my name is $name"
case right now but i will add the "${image}.jpg" case shortly.
Revision Changes Path
1.5 +68 -7
jakarta-velocity/src/java/org/apache/velocity/runtime/parser/node/NodeUtils.java
Index: NodeUtils.java
===================================================================
RCS file:
/home/cvs/jakarta-velocity/src/java/org/apache/velocity/runtime/parser/node/NodeUtils.java,v
retrieving revision 1.4
retrieving revision 1.5
diff -u -r1.4 -r1.5
--- NodeUtils.java 2000/11/07 21:31:05 1.4
+++ NodeUtils.java 2000/11/28 00:55:41 1.5
@@ -52,20 +52,29 @@
* <http://www.apache.org/>.
*/
+package org.apache.velocity.runtime.parser.node;
+
+import org.apache.velocity.Context;
+import org.apache.velocity.runtime.parser.*;
+
/**
* Utilities for dealing with the AST node structure.
*
* @author <a href="mailto:[EMAIL PROTECTED]">Jason van Zyl</a>
* @author <a href="mailto:[EMAIL PROTECTED]">Geir Magnusson Jr.</a>
- * @version $Id: NodeUtils.java,v 1.4 2000/11/07 21:31:05 geirm Exp $
+ * @version $Id: NodeUtils.java,v 1.5 2000/11/28 00:55:41 jvanzyl Exp $
*/
-
-package org.apache.velocity.runtime.parser.node;
-
-import org.apache.velocity.runtime.parser.*;
-
public class NodeUtils
{
+ /**
+ * Collect all the <SPECIAL_TOKEN>s that
+ * are carried along with a token. Special
+ * tokens do not participate in parsing but
+ * can still trigger certain lexical actions.
+ * In some cases you may want to retrieve these
+ * special tokens, this is simply a way to
+ * extract them.
+ */
public static String specialText(Token t)
{
String specialText = "";
@@ -86,6 +95,58 @@
return specialText;
}
+
+ /**
+ * Utility method to interpolate context variables
+ * into string literals. So that the following will
+ * work:
+ *
+ * #set $name = "candy"
+ * $image.getURI("${name}.jpg")
+ *
+ * And the string literal argument will
+ * be transformed into "candy.jpg" before
+ * the method is executed.
+ */
+ public String interpolate(String argStr, Context vars)
+ {
+ StringBuffer argBuf = new StringBuffer();
-}
+ for (int cIdx = 0 ; cIdx < argStr.length();)
+ {
+ char ch = argStr.charAt(cIdx);
+ switch (ch)
+ {
+ case '$':
+ StringBuffer nameBuf = new StringBuffer();
+ for (++cIdx ; cIdx < argStr.length(); ++cIdx)
+ {
+ ch = argStr.charAt(cIdx);
+ if (ch == '_' || Character.isLetterOrDigit(ch))
+ nameBuf.append(ch);
+ else
+ break;
+ }
+
+ if (nameBuf.length() > 0)
+ {
+ String value = (String) vars.get(nameBuf.toString());
+
+ if (value != null)
+ {
+ argBuf.append(value);
+ }
+ }
+ break;
+
+ default:
+ argBuf.append(ch);
+ ++cIdx;
+ break;
+ }
+ }
+
+ return argBuf.toString();
+ }
+}
