/**
* Replaces <code>${xxx}</code> style constructions in the given value with the string value of
* the corresponding data types.
*
* @param value The string to be scanned for property references. May be <code>null</code>, in
* which case this method returns immediately with no effect.
* @param keys Mapping (String to String) of property names to their values. If <code>null</code>,
* only project properties will be used.
* @exception BuildException if the string contains an opening <code>${</code> without a closing
* <code>}</code>
* @return the original string with the properties replaced, or <code>null</code> if the original
* string is <code>null</code>.
*/
public String replaceProperties(String ns, String value, Hashtable keys) throws BuildException {
if (value == null) {
return null;
}
Vector fragments = new Vector();
Vector propertyRefs = new Vector();
parsePropertyString(value, fragments, propertyRefs);
StringBuffer sb = new StringBuffer();
Enumeration i = fragments.elements();
Enumeration j = propertyRefs.elements();
while (i.hasMoreElements()) {
String fragment = (String) i.nextElement();
if (fragment == null) {
String propertyName = (String) j.nextElement();
Object replacement = null;
// try to get it from the project or keys
// Backward compatibility
if (keys != null) {
replacement = keys.get(propertyName);
}
if (replacement == null) {
replacement = getProperty(ns, propertyName);
}
if (replacement == null) {
project.log("Property ${" + propertyName + "} has not been set", Project.MSG_VERBOSE);
}
fragment = (replacement != null) ? replacement.toString() : "${" + propertyName + "}";
}
sb.append(fragment);
}
return sb.toString();
}
