Added 'prefix' option to <property>. Designed to only work when loading a property file or resource.

git-svn-id: https://svn.apache.org/repos/asf/ant/core/trunk@271519 13f79535-47bb-0310-9956-ffa450edef68

src/etc/testcases/taskdefs/property.xml

@@ -21,4 +21,13 @@
     <property file="property3.properties"/>
     <echo message="http.url is ${http.url}"/>
   </target>
+  
+  <target name="prefix.success">
+    <property file="property3.properties" prefix="server1"/>
+  </target>
+
+  <target name="prefix.fail">
+    <property name="someprop" value="value" prefix="prefix"/>
+  </target>
+  
 </project>

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

@@ -86,6 +86,7 @@ public class Property extends Task {
     protected Path classpath;
     protected String env;
     protected Reference ref;
+    protected String prefix;
 
     protected boolean userProperty; // set read-only properties
 
@@ -124,6 +125,13 @@ public class Property extends Task {
     public File getFile() {
         return file;
     }
+    
+    public void setPrefix(String prefix) {
+        this.prefix = prefix;
+        if (!prefix.endsWith(".")) {
+          this.prefix += ".";
+        }
+    }
 
     public void setRefid(Reference ref) {
         this.ref = ref;
@@ -192,6 +200,10 @@ public class Property extends Task {
                                          location);
             }
         }
+        
+        if (file == null && resource == null && prefix != null) {
+            throw new BuildException("Prefix is only valid when loading from a file or resource", location);
+        }
 
         if ((name != null) && (value != null)) {
             addProperty(name, value);
@@ -298,6 +310,11 @@ public class Property extends Task {
             String value = props.getProperty(name);
 
             String v = project.replaceProperties(value);
+
+            if (prefix != null) {
+                name = prefix + name;
+            }
+
             addProperty(name, v);
         }
     }

src/testcases/org/apache/tools/ant/taskdefs/PropertyTest.java

@@ -95,4 +95,21 @@ public class PropertyTest extends BuildFileTest {
         expectLog("test4", "http.url is http://localhost:999");
     }
     
+    public void testPrefixSuccess() {
+        executeTarget("prefix.success");
+        assertEquals("80", project.getProperty("server1.http.port"));
+    }
+
+    public void testPrefixFailure() {
+       try {
+            executeTarget("prefix.fail");
+        }
+        catch (BuildException e) {
+            assertEquals("Prefix allowed on non-resource/file load - ", true,
+                     e.getMessage().indexOf("Prefix is only valid") != -1);
+            return;                     
+        }
+        fail("Did not throw exception on invalid use of prefix");
+    }
+    
 }