wildcards in packages definition

pom.xml

@@ -126,6 +126,11 @@
       <artifactId>commons-io</artifactId>
       <version>2.5</version>
     </dependency>
+    <dependency>
+      <groupId>org.apache.commons</groupId>
+      <artifactId>commons-lang3</artifactId>
+      <version>3.5</version>
+    </dependency>
 
     <!-- maven plugin dependencies -->
     <dependency>

src/main/java/org/assertj/maven/generator/AssertionsGenerator.java

@@ -102,8 +102,9 @@ public AssertionsGeneratorReport generateAssertionsFor(String[] inputPackages, S
     Set<ClassDescription> classDescriptions = new HashSet<>();
     report.setInputPackages(inputPackages);
     report.setInputClasses(inputClassNames);
+    final String[] resolvedPackages = new PackagesResolver(classLoader, inputPackages, log).getPackages();
     try {
-      Set<TypeToken<?>> classes = collectClasses(classLoader, includePackagePrivateClasses, addAll(inputPackages, inputClassNames));
+      Set<TypeToken<?>> classes = collectClasses(classLoader, includePackagePrivateClasses, addAll(resolvedPackages, inputClassNames));
       report.reportInputClassesNotFound(classes, inputClassNames);
       Set<TypeToken<?>> filteredClasses = removeAssertClasses(classes);
       removeClassesAccordingToIncludeAndExcludePatterns(filteredClasses);

src/main/java/org/assertj/maven/generator/PackagesResolver.java

@@ -0,0 +1,119 @@
+/**
+ * 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.
+ *
+ * Copyright 2012-2017 the original author or authors.
+ */
+package org.assertj.maven.generator;
+
+import java.io.IOException;
+import java.util.ArrayList;
+import java.util.Arrays;
+import java.util.Collection;
+import java.util.LinkedHashSet;
+import java.util.List;
+import java.util.regex.Pattern;
+import java.util.regex.PatternSyntaxException;
+
+import org.apache.commons.lang3.StringUtils;
+import org.apache.maven.plugin.logging.Log;
+import org.assertj.maven.NoLog;
+
+import com.google.common.reflect.ClassPath;
+import com.google.common.reflect.ClassPath.ClassInfo;
+
+public class PackagesResolver {
+  private final ClassLoader classloader;
+  private final Collection<String> inputPackages;
+  private final Log logger;
+
+  public PackagesResolver(final ClassLoader classloader, final String[] inputPackages,
+                          final Log logger) {
+    super();
+    this.classloader = classloader;
+    this.inputPackages = (inputPackages == null || inputPackages.length == 0)
+        ? new LinkedHashSet<String>()
+        : new LinkedHashSet<String>(Arrays.asList(inputPackages));
+    this.logger = (logger == null) ? new NoLog() : logger;
+  }
+
+  public String[] getPackages() {
+    final String[] resolvedPackages;
+    if (!hasWildcards())
+    {
+      resolvedPackages = inputPackages.toArray(new String[inputPackages.size()]);
+    } else {
+      final Collection<String> resolvedPackagesList = new LinkedHashSet<>();
+      final Collection<Pattern> patterns = getPatterns();
+
+      try {
+        for (final ClassInfo classInfo : ClassPath.from(classloader).getTopLevelClasses()) {
+          if (matches(classInfo, patterns)) {
+            resolvedPackagesList.add(classInfo.getPackageName());
+          }
+        }
+      } catch (IOException e) {
+        logger.warn("fail to detect packages dynamically", e);
+        resolvedPackagesList.addAll(inputPackages);
+      }
+
+      resolvedPackages = resolvedPackagesList.toArray(new String[resolvedPackagesList.size()]);
+    }
+
+    logger.info("resolved packages to generate assertions: " + Arrays.toString(resolvedPackages));
+    return resolvedPackages;
+  }
+
+  protected boolean hasWildcards() {
+    boolean result = false;
+
+    if (inputPackages != null && !inputPackages.isEmpty()) {
+      for (final String inputPackage : inputPackages) {
+        result = result || StringUtils.contains(inputPackage, "*");
+      }
+    }
+
+    return result;
+  }
+
+  protected Collection<Pattern> getPatterns() {
+    final List<Pattern> patterns = new ArrayList<>();
+
+    for (final String inputPackage : inputPackages) {
+      String pattern = StringUtils.replace(inputPackage, ".", "\\.");
+      pattern = StringUtils.replace(pattern, "*", "(.*)");
+
+      if (!StringUtils.endsWith(pattern, "(.*)")) {
+        pattern += "(.*)";
+      }
+
+      try {
+        patterns.add(Pattern.compile(pattern));
+      } catch (PatternSyntaxException e) {
+        logger.warn("fail to select packages with the following java regular expression -> " + pattern + " (" + inputPackage
+                    + ") because: ", e);
+      }
+    }
+
+    return patterns;
+  }
+
+  protected boolean matches(final ClassInfo classInfo, final Collection<Pattern> patterns) {
+    boolean match = false;
+
+    for (final Pattern pattern : patterns) {
+      match = match || pattern.matcher(classInfo.getPackageName()).matches();
+      if (match) {
+        break;
+      }
+    }
+
+    return match;
+  }
+}