Added a check on Property names using the "if" and "unless" attributes

docs/manual/CoreTypes/selectors-program.html

@@ -76,7 +76,7 @@ to
             <code>isSelected()</code> method call <code>validate()</code> and
             a BuildException will be thrown with the contents of your error
             message. The <code>validate()</code> method also gives you a
-            last change to check your settings for consistency because it
+            last chance to check your settings for consistency because it
             calls <code>verifySettings()</code>. Override this method and
             call <code>setError()</code> within it if you detect any
             problems in how your selector is set up.</p>

docs/manual/CoreTypes/selectors.html

@@ -23,21 +23,21 @@
     contain other selectors, and these are called 
     <a href="#selectcontainers"><code>Selector Containers</code></a>. 
     There is also a category of selectors that allow
-    user-defined extensions, called 
+    user-defined extensions, called
     <a href="#customselect"><code>Custom Selectors</code></a>.
     The ones built in to Ant are called 
     <a href="#coreselect"><code>Core Selectors</code></a>.
     </p>
-    
+
     <a name="coreselect"></a>
     <h3>Core Selectors</h3>
 
     <p>Core selectors are the ones that come standard
     with Ant. They can be used within a fileset and can be contained
     within Selector Containers.</p>
-    
+
     <p>The core selectors are:</p>
-    
+
     <ul>
       <li><a href="#containsselect">&lt;contains&gt;</a> - Select
         files that contain a particular text string
@@ -161,7 +161,7 @@
     <h4>Depend Selector</h4>
 
     <p>The <code>&lt;depend&gt;</code> tag selects files
-    whose last modified date is later than another, equivalent file in 
+    whose last modified date is later than another, equivalent file in
     another location.</p>
     
     <p>The <code>&lt;depend&gt;</code> tag supports the use of a
@@ -443,9 +443,13 @@
       <li><a href="#orselect">&lt;or&gt;</a> - selects a file if any one
         of the contained selectors selects it.
       <li><a href="#selectorselect">&lt;selector&gt;</a> - contains only one
-        selector and forwards all requests to it without alteration. This
+        selector and forwards all requests to it without alteration, provided
+        that any <code>&quot;if&quot;</code> or
+        <code>&quot;unless&quot;</code> conditions are met. This
         is the selector to use if you want to define a reference. It is
-        usable as an element of <code>&lt;project&gt;</code>.
+        usable as an element of <code>&lt;project&gt;</code>. It is also
+        the one to use if you want selection of files to be dependent on
+        Ant property settings.
     </ul>
 
     <p>All selector containers can contain any other selector, including
@@ -618,12 +622,43 @@
     <h4>Selector Reference</h4>
 
     <p>The <code>&lt;selector&gt;</code> tag is used to create selectors
-    that can be reused through references. It should be used outside of
+    that can be reused through references. It is the only selector which can
+    be used outside of
     any target, as an element of the <code>&lt;project&gt;</code> tag. It
     can contain only one other selector, but of course that selector can
     be a container.
     </p>
 
+    <p>The <code>&lt;selector&gt;</code> tag can also be used to select
+    files conditionally based on whether an Ant property exists or not.
+    This functionality is realized using the <code>&quot;if&quot;</code> and
+    <code>&quot;unless&quot;</code> attributes in exactly the same way they
+    are used on targets or on the <code>&lt;include&gt;</code> and
+    <code>&lt;exclude&gt;</code> tags within a
+    <code>&lt;patternset&gt;</code>.</p>
+
+    <table border="1" cellpadding="2" cellspacing="0">
+      <tr>
+        <td valign="top"><b>Attribute</b></td>
+        <td valign="top"><b>Description</b></td>
+        <td align="center" valign="top"><b>Required</b></td>
+      </tr>
+      <tr>
+        <td valign="top">if</td>
+        <td valign="top">Allow files to be selected only if the named
+          property is set.
+        </td>
+        <td valign="top" align="center">No</td>
+      </tr>
+      <tr>
+        <td valign="top">unless</td>
+        <td valign="top">Allow files to be selected only if the named
+          property is <b>not</b> set.
+        </td>
+        <td valign="top" align="center">No</td>
+      </tr>
+    </table>
+
     <p>Here is an example of how to use the Selector Reference:</p>
 
     <blockquote><pre>
@@ -647,7 +682,7 @@
             &lt;/fileset&gt;
         &lt;/zip&gt;
     &lt;/target&gt;
-    
+
 &lt;/project&gt;
 </pre></blockquote>
 
@@ -655,18 +690,42 @@
     class file and javadoc file associated with them.
     </p>
 
+    <p>And an example of selecting files conditionally, based on whether
+    properties are set:</p>
+
+    <blockquote><pre>
+&lt;fileset dir=&quot;${working.copy}&quot;&gt;
+    &lt;or&gt;
+        &lt;selector if=&quot;include.tests&quot;&gt;
+            &lt;filename name=&quot;**/*Test.class&quot;&gt;
+        &lt;/selector&gt;
+        &lt;selector if=&quot;include.source&quot;&gt;
+            &lt;and&gt;
+                &lt;filename name=&quot;**/*.java&quot;&gt;
+                &lt;not&gt;
+                    &lt;selector unless=&quot;include.tests&quot;&gt;
+                        &lt;filename name=&quot;**/*Test.java&quot;&gt;
+                    &lt;/selector&gt;
+                &lt;/not&gt;
+            &lt;/and&gt;
+        &lt;/selector&gt;
+    &lt;/or&gt;
+&lt;/fileset&gt;
+</pre></blockquote>
 
+    <p>A fileset that conditionally contains Java source files and Test
+    source and class files.</p>
 
     <a name="customselect"></a>
     <h3>Custom Selectors</h3>
 
-    <p>You can write your own selectors and use them within the selector 
+    <p>You can write your own selectors and use them within the selector
     containers by specifying them within the &lt;custom&gt; tag.</p>
 
     <p>First, you have to write your selector class in Java. The only
     requirement it must meet in order to be a selector is that it implements
     the <code>org.apache.tools.ant.types.selectors.FileSelector</code>
-    interface, which contains a single method. See 
+    interface, which contains a single method. See
     <a href="selectors-program.html">Programming Selectors in Ant</a> for
     more information.</p>
 

src/main/org/apache/tools/ant/types/selectors/SelectSelector.java

@@ -55,6 +55,8 @@
 package org.apache.tools.ant.types.selectors;
 
 import java.util.Enumeration;
+import java.io.File;
+
 import org.apache.tools.ant.Project;
 
 /**
@@ -68,7 +70,10 @@ import org.apache.tools.ant.Project;
  * @author <a href="mailto:bruce@callenish.com">Bruce Atherton</a>
  * @since 1.5
  */
-public class SelectSelector extends AndSelector {
+public class SelectSelector extends BaseSelectorContainer {
+
+    private String ifProperty;
+    private String unlessProperty;
 
     /**
      * Default constructor.
@@ -79,7 +84,16 @@ public class SelectSelector extends AndSelector {
     public String toString() {
         StringBuffer buf = new StringBuffer();
         if (hasSelectors()) {
-            buf.append("{select: ");
+            buf.append("{select");
+            if (ifProperty != null) {
+                buf.append(" if: ");
+                buf.append(ifProperty);
+            }
+            if (unlessProperty != null) {
+                buf.append(" unless: ");
+                buf.append(unlessProperty);
+            }
+            buf.append(" ");
             buf.append(super.toString());
             buf.append("}");
         }
@@ -155,11 +169,71 @@ public class SelectSelector extends AndSelector {
      * not.
      */
     public void verifySettings() {
-        if (selectorCount() != 1) {
-            setError("One and only one selector is allowed within the " +
+        int cnt = selectorCount();
+        if (cnt < 0 || cnt > 1) {
+            setError("Only one selector is allowed within the " +
                     "<select> tag");
         }
     }
 
+    /**
+     * Ensures that the selector passes the conditions placed
+     * on it with <code>if</code> and <code>unless</code>.
+     */
+    public boolean passesConditions() {
+            if (ifProperty != null &&
+                    getProject().getProperty(ifProperty) == null) {
+                return false;
+            } else if (unlessProperty != null &&
+                    getProject().getProperty(unlessProperty) != null) {
+                return false;
+            }
+            return true;
+    }
+
+    /**
+     * Sets the if attribute to a property which must exist for the
+     * selector to select any files.
+     */
+    public void setIf(String ifProperty) {
+        this.ifProperty = ifProperty;
+    }
+
+    /**
+     * Sets the unless attribute to a property which cannot exist for the
+     * selector to select any files.
+     */
+    public void setUnless(String unlessProperty) {
+        this.unlessProperty = unlessProperty;
+    }
+
+    /**
+     * Returns true (the file is selected) only if the if property (if any)
+     * exists, the unless property (if any) doesn't exist, and the
+     * contained selector (if any) selects the file. If there is no contained
+     * selector, return true (because we assume that the point was to test
+     * the if and unless conditions).
+     *
+     * @param basedir the base directory the scan is being done from
+     * @param filename the name of the file to check
+     * @param file a java.io.File object for the filename that the selector
+     * can use
+     * @return whether the file should be selected or not
+     */
+    public boolean isSelected(File basedir, String filename, File file) {
+        validate();
+
+        // Deal with if and unless properties first
+        if (!(passesConditions())) {
+            return false;
+        }
+
+        Enumeration e = selectorElements();
+        if (!(e.hasMoreElements())) {
+            return true;
+        }
+        FileSelector f = (FileSelector)e.nextElement();
+        return f.isSelected(basedir,filename,file);
+    }
 }