Added a helper class for enumerated attributes and demonstrated its

usage in FixCRLF.


git-svn-id: https://svn.apache.org/repos/asf/ant/core/trunk@267766 13f79535-47bb-0310-9956-ffa450edef68

docs/index.html

@@ -3171,6 +3171,10 @@ output.
     value of the attribute is interpreted relative to the project's basedir) 
     or any other type that has a constructor with a single <code>String</code>
     argument</li>
+  <li>If your task has enumerated attributes, you should consider using
+    a subclass of org.apache.tools.ant.EnumeratedAttribute as argument
+    to your setter method. See org.apache.tools.ant.taskdefs.FixCRLF for
+    an example.</li>
   <li>If the task should support character data, write a <code>public void 
     addText(String)</code> method.</li>
   <li>For each nested element, write a create or add method. A create method 

src/main/org/apache/tools/ant/IntrospectionHelper.java

@@ -438,6 +438,23 @@ public class IntrospectionHelper  {
 
                 };
 
+        // EnumeratedAttributes have their own helper class
+        } else if (org.apache.tools.ant.EnumeratedAttribute.class.isAssignableFrom(arg)) {
+            return new AttributeSetter() {
+                    public void set(Project p, Object parent, String value) 
+                        throws InvocationTargetException, IllegalAccessException, BuildException {
+                        try {
+                            EnumeratedAttribute ea = 
+                                (EnumeratedAttribute)arg.newInstance();
+                            ea.setValue(value);
+                            m.invoke(parent, new EnumeratedAttribute[] {ea});
+                        } catch (InstantiationException ie) {
+                            throw new BuildException(ie);
+                        }
+                    }
+                };
+        
+
         // worst case. look for a public String constructor and use it
         } else {
 

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

@@ -139,15 +139,15 @@ public class FixCRLF extends MatchingTask {
      * <li>remove: remove all CR characters
      * </ul>
      */
-    public void setCr(String option) {
+    public void setCr(AddAsisRemove attr) {
+        String option = attr.getValue();
         if (option.equals("remove")) {
             addcr = -1;
         } else if (option.equals("asis")) {
             addcr = 0;
-        } else if (option.equals("add")) {
-            addcr = +1;
         } else {
-            throw new BuildException("Invalid option: " + option );
+            // must be "add"
+            addcr = +1;
         }
     }
 
@@ -161,15 +161,15 @@ public class FixCRLF extends MatchingTask {
      * <li>remove: convert tabs to spaces
      * </ul>
      */
-    public void setTab(String option) {
+    public void setTab(AddAsisRemove attr) {
+        String option = attr.getValue();
         if (option.equals("remove")) {
             addtab = -1;
         } else if (option.equals("asis")) {
             addtab = 0;
-        } else if (option.equals("add")) {
-            addtab = +1;
         } else {
-            throw new BuildException("Invalid option: " + option );
+            // must be "add"
+            addtab = +1;
         }
     }
 
@@ -196,15 +196,15 @@ public class FixCRLF extends MatchingTask {
      * <li>remove: remove any eof character found at the end
      * </ul>
      */
-    public void setEof(String option) {
+    public void setEof(AddAsisRemove attr) {
+        String option = attr.getValue();
         if (option.equals("remove")) {
             ctrlz = -1;
         } else if (option.equals("asis")) {
             ctrlz = 0;
-        } else if (option.equals("add")) {
-            ctrlz = +1;
         } else {
-            throw new BuildException("Invalid option: " + option );
+            // must be "add"
+            ctrlz = +1;
         }
     }
 
@@ -370,4 +370,13 @@ public class FixCRLF extends MatchingTask {
 
         } /* end for */
     }
+
+    /**
+     * Enumerated attribute with the values "asis", "add" and "remove".
+     */
+    public static class AddAsisRemove extends EnumeratedAttribute {
+        public String[] getValues() {
+            return new String[] {"add", "asis", "remove"};
+        }
+    }
 }