add missing file for the set properties capabilities

git-svn-id: https://svn.apache.org/repos/asf/maven/components/trunk@189512 13f79535-47bb-0310-9956-ffa450edef68

maven-artifact-ant/src/main/java/org/apache/maven/artifact/ant/SetPropertyTask.java

@@ -0,0 +1,112 @@
+package org.apache.maven.artifact.ant;
+
+/*
+ * Copyright 2001-2005 The Apache Software Foundation.
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+import org.apache.maven.artifact.repository.ArtifactRepository;
+import org.apache.maven.project.MavenProjectBuilder;
+import org.apache.tools.ant.BuildException;
+import org.codehaus.plexus.util.introspection.ReflectionValueExtractor;
+
+/**
+ * Set a property from a POM.
+ *
+ * @author <a href="mailto:brett@apache.org">Brett Porter</a>
+ * @version $Id$
+ */
+public class SetPropertyTask
+    extends AbstractArtifactTask
+{
+    private String ref;
+
+    private String property;
+
+    private String expression;
+
+    public void execute()
+        throws BuildException
+    {
+        ArtifactRepository localRepo = createLocalArtifactRepository();
+
+        MavenProjectBuilder builder = (MavenProjectBuilder) lookup( MavenProjectBuilder.ROLE );
+        Pom pom = buildPom( builder, localRepo );
+
+        if ( expression == null )
+        {
+            throw new BuildException( "the expression attribute is required" );
+        }
+
+        if ( property == null && ref == null )
+        {
+            throw new BuildException( "the property or ref attribute is required" );
+        }
+
+        else if ( property != null && ref != null )
+        {
+            throw new BuildException( "only one of the property or ref attribute is allowed" );
+
+        }
+
+        Object value = null;
+        try
+        {
+            value = ReflectionValueExtractor.evaluate( expression, pom.getMavenProject() );
+        }
+        catch ( Exception e )
+        {
+            throw new BuildException( "Error extracting expression from POM", e );
+        }
+
+        if ( property != null )
+        {
+            getProject().setProperty( property, value.toString() );
+        }
+        else
+        {
+            getProject().addReference( ref, value );
+        }
+    }
+
+    public String getProperty()
+    {
+        return property;
+    }
+
+    public void setProperty( String property )
+    {
+        this.property = property;
+    }
+
+    public String getExpression()
+    {
+        return expression;
+    }
+
+    public void setExpression( String expression )
+    {
+        this.expression = expression;
+    }
+
+    public String getRef()
+    {
+        return ref;
+    }
+
+    public void setRef( String ref )
+    {
+        this.ref = ref;
+    }
+}