CLI-144: validate() is now called only once for an option that belongs to a group.

Thanks to David dot Biesack at sas dot com for the unit test and dioktos at gmail dot com for a proposed fix.

git-svn-id: https://svn.apache.org/repos/asf/commons/proper/cli/trunk@679179 13f79535-47bb-0310-9956-ffa450edef68

Author: Oliver Heger

src/java/org/apache/commons/cli2/option/GroupImpl.java

@@ -245,14 +245,8 @@ public void validate(final WriteableCommandLine commandLine)
         for (final Iterator i = options.iterator(); i.hasNext();) {
             final Option option = (Option) i.next();
 
-            // if the child option is required then validate it
-            if (option.isRequired()) {
-                option.validate(commandLine);
-            }
-
-            if (option instanceof Group) {
-                option.validate(commandLine);
-            }
+            // needs validation?
+            boolean validate = option.isRequired() || option instanceof Group;
 
             // if the child option is present then validate it
             if (commandLine.hasOption(option)) {
@@ -261,7 +255,10 @@ public void validate(final WriteableCommandLine commandLine)
 
                     break;
                 }
+                validate = true;
+            }
 
+            if (validate) {
                 option.validate(commandLine);
             }
         }

src/test/org/apache/commons/cli2/bug/BugCLI144Test.java

@@ -0,0 +1,66 @@
+/**
+ * Licensed to the Apache Software Foundation (ASF) under one or more
+ * contributor license agreements.  See the NOTICE file distributed with
+ * this work for additional information regarding copyright ownership.
+ * The ASF licenses this file to You 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.
+ */
+package org.apache.commons.cli2.bug;
+
+import java.io.File;
+
+import junit.framework.TestCase;
+
+import org.apache.commons.cli2.CommandLine;
+import org.apache.commons.cli2.Group;
+import org.apache.commons.cli2.builder.ArgumentBuilder;
+import org.apache.commons.cli2.builder.DefaultOptionBuilder;
+import org.apache.commons.cli2.builder.GroupBuilder;
+import org.apache.commons.cli2.commandline.Parser;
+import org.apache.commons.cli2.option.DefaultOption;
+import org.apache.commons.cli2.validation.FileValidator;
+
+/**
+ * Test case for http://issues.apache.org/jira/browse/CLI-144 CLI 2 throws
+ *
+ * <pre>
+ * Exception in thread &quot;main&quot; java.lang.ClassCastException: java.io.File cannot be cast to java.lang.String
+ * </pre>
+ *
+ * when there should be no such exception
+ *
+ * @author David Biesack
+ */
+public class BugCLI144Test extends TestCase {
+	public void testFileValidator() {
+		final DefaultOptionBuilder obuilder = new DefaultOptionBuilder();
+        final ArgumentBuilder abuilder = new ArgumentBuilder();
+        final GroupBuilder gbuilder = new GroupBuilder();
+        DefaultOption fileNameOption = obuilder.withShortName("f")
+                .withLongName("file-name").withRequired(true).withDescription(
+                        "name of an existing file").withArgument(
+                        abuilder.withName("file-name").withValidator(
+                                FileValidator.getExistingFileInstance())
+                                .create()).create();
+        Group options = gbuilder.withName("options").withOption(fileNameOption)
+                .create();
+        Parser parser = new Parser();
+        parser.setHelpTrigger("--help");
+        parser.setGroup(options);
+
+        final String fileName = "src/test/org/apache/commons/cli2/bug/BugCLI144Test.java";
+        CommandLine cl = parser
+                .parseAndHelp(new String[] { "--file-name", fileName });
+        assertNotNull(cl);
+        assertEquals("Wrong file", new File(fileName), cl.getValue(fileNameOption));
+	}
+}