use adapter for Touchable instead of instanceof checks

git-svn-id: https://svn.apache.org/repos/asf/ant/core/trunk@718210 13f79535-47bb-0310-9956-ffa450edef68

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

@@ -299,7 +299,8 @@ public class Touch extends Task {
         Iterator iter = resources.iterator();
         while (iter.hasNext()) {
             Resource r = (Resource) iter.next();
-            if (!(r instanceof Touchable)) {
+            Touchable t = (Touchable) r.as(Touchable.class);
+            if (t == null) {
                 throw new BuildException("Can't touch " + r);
             }
             touch(r, defaultTimestamp);
@@ -343,7 +344,7 @@ public class Touch extends Task {
                 // use this to create file and deal with non-writable files
                 touch(((FileProvider) r).getFile(), defaultTimestamp);
             } else {
-                ((Touchable) r).touch(defaultTimestamp);
+                ((Touchable) r.as(Touchable.class)).touch(defaultTimestamp);
             }
         } else {
             String[] mapped = fileNameMapper.mapFileName(r.getName());

src/main/org/apache/tools/ant/types/resources/MappedResource.java

@@ -38,6 +38,7 @@ import org.apache.tools.ant.types.Resource;
 public class MappedResource extends Resource {
     private final Resource wrapped;
     private final boolean isAppendable;
+    private final boolean isTouchable;
 
     // should only be instantiated via factory, this also means we
     // don't have to think about being a reference to a different
@@ -49,6 +50,7 @@ public class MappedResource extends Resource {
     protected MappedResource(Resource r) {
         wrapped = r;
         isAppendable = wrapped.as(Appendable.class) != null;
+        isTouchable = wrapped.as(Touchable.class) != null;
     }
 
     /**
@@ -162,21 +164,19 @@ public class MappedResource extends Resource {
                 }
             };
         }
+        if (clazz == Touchable.class && isTouchable) {
+            return new Touchable() {
+                public void touch(long modTime) {
+                    ((Touchable) wrapped.as(Touchable.class)).touch(modTime);
+                }
+            };
+        }
         return super.as(clazz);
     }
 
     public static MappedResource map(Resource r) {
-        if (r instanceof FileProvider) {
-            if (r instanceof Touchable) {
-                return new TouchableFileProviderMR(r);
-            }
-            return new FileProviderMR(r);
-        }
-        if (r instanceof Touchable) {
-            return new TouchableMR(r);
-        }
-        // no special interface
-        return new MappedResource(r);
+        return r instanceof FileProvider
+            ? new FileProviderMR(r) : new MappedResource(r);
     }
 
     private static class FileProviderMR extends MappedResource
@@ -201,48 +201,4 @@ public class MappedResource extends Resource {
         }
     }
 
-    private static class TouchableMR extends MappedResource
-        implements Touchable {
-        private final Touchable t;
-
-        protected TouchableMR(Resource r) {
-            super(r);
-            if (!(r instanceof Touchable)) {
-                throw new IllegalArgumentException("trying to wrap something "
-                                                   + "that is not a "
-                                                   + " Touchable");
-            }
-            t = (Touchable) r;
-        }
-
-        /**
-         * delegated to the wrapped resource.
-         */
-        public void touch(long m) {
-            t.touch(m);
-        }
-    }
-
-    private static class TouchableFileProviderMR extends FileProviderMR
-        implements Touchable {
-        private final Touchable t;
-
-        protected TouchableFileProviderMR(Resource r) {
-            super(r);
-            if (!(r instanceof Touchable)) {
-                throw new IllegalArgumentException("trying to wrap something "
-                                                   + "that is not a "
-                                                   + " Touchable");
-            }
-            t = (Touchable) r;
-        }
-
-        /**
-         * delegated to the wrapped resource.
-         */
-        public void touch(long m) {
-            t.touch(m);
-        }
-    }
-
 }

src/main/org/apache/tools/ant/util/ResourceUtils.java

@@ -421,8 +421,11 @@ public class ResourceUtils {
                 FileUtils.close(in);
             }
         }
-        if (preserveLastModified && dest instanceof Touchable) {
-            setLastModified((Touchable) dest, source.getLastModified());
+        if (preserveLastModified) {
+            Touchable t = (Touchable) dest.as(Touchable.class);
+            if (t != null) {
+                setLastModified(t, source.getLastModified());
+            }
         }
     }
     // CheckStyle:ParameterNumberCheck ON