Class.forName("") throws an IllegalArgumentException instead of

ClassNotFoundException in JDK 1.1. Make available behavior consistent
by ignoring empty classname attributes.


git-svn-id: https://svn.apache.org/repos/asf/ant/core/trunk@268044 13f79535-47bb-0310-9956-ffa450edef68

src/etc/testcases/taskdefs/available.xml

@@ -75,7 +75,7 @@
 
   <target name="test15">
     <available property="test" 
-               classname=""/>
+               classname="org.apache.tools.ant.taskdefs.this_class_does_not_exist"/>
   </target>
 
 </project>

src/main/org/apache/tools/ant/taskdefs/Available.java

@@ -103,7 +103,9 @@ public class Available extends Task {
     }
 
     public void setClassname(String classname) {
-        this.classname = classname;
+        if (!"".equals(classname)) {
+            this.classname = classname;
+        }
     }
 
     public void setFile(File file) {