Add warning that generate features modifies the source directory

Signed-off-by: Kathryn Kodama <kathryn.s.kodama@gmail.com>

README.md

@@ -99,7 +99,7 @@ The Liberty Maven Plugin provides the following goals.
 | [devc](docs/dev.md#devc-container-mode) | Start a Liberty server in dev mode in a container. |
 | [display-url](docs/display-url.md#display-url) | Display the application URL in the default browser. |
 | [dump](docs/dump.md#dump) | Dump diagnostic information from the server into an archive. |
-| [generate-features](docs/generate-features.md#generate-feature) | Scan the class files of an application and create a Liberty configuration file containing the Liberty features the application requires. |
+| [generate-features](docs/generate-features.md#generate-feature) | Scan the class files of an application and create a Liberty configuration file in the source configuration directory containing the Liberty features the application requires. |
 | [install-feature](docs/install-feature.md#install-feature) | Install a feature packaged as a Subsystem Archive (esa) to the Liberty runtime. |
 | [install-server](docs/install-server.md#install-server) | Installs the Liberty runtime. This goal is implicitly invoked by all the other plugin goals and usually does not need to be executed explicitly. |
 | [java-dump](docs/java-dump.md#java-dump) | Dump diagnostic information from the server JVM. |

liberty-maven-plugin/src/main/java/io/openliberty/tools/maven/server/DevMojo.java

@@ -62,6 +62,7 @@
 import org.twdata.maven.mojoexecutor.MojoExecutor.Element;
 
 import io.openliberty.tools.ant.ServerTask;
+import io.openliberty.tools.common.plugins.util.BinaryScannerUtil;
 import io.openliberty.tools.common.plugins.util.DevUtil;
 import io.openliberty.tools.common.plugins.util.InstallFeatureUtil;
 import io.openliberty.tools.common.plugins.util.JavaCompilerOptions;
@@ -1279,6 +1280,17 @@ protected void doExecute() throws Exception {
                 // generate features on startup - provide all classes and only user specified
                 // features to binary scanner
                 try {
+                    String generatedFileCanonicalPath;
+                    try {
+                        generatedFileCanonicalPath = new File(configDirectory,
+                                BinaryScannerUtil.GENERATED_FEATURES_FILE_PATH).getCanonicalPath();
+                    } catch (IOException e) {
+                        generatedFileCanonicalPath = new File(configDirectory,
+                                BinaryScannerUtil.GENERATED_FEATURES_FILE_PATH).toString();
+                    }
+                    log.warn(
+                            "The source configuration directory will be modified. Features will automatically be generated in a new file: "
+                                    + generatedFileCanonicalPath);
                     runLibertyMojoGenerateFeatures(null, true);
                 } catch (MojoExecutionException e) {
                     if (e.getCause() != null && e.getCause() instanceof PluginExecutionException) {