Add API method to JavaPackage to access package-info.java

Issue TNG#263

Signed-off-by: Roland Weisleder <[email protected]>

archunit/src/main/java/com/tngtech/archunit/core/domain/JavaPackage.java

@@ -33,6 +33,7 @@
 import com.tngtech.archunit.base.DescribedPredicate;
 import com.tngtech.archunit.base.Optional;
 import com.tngtech.archunit.base.Predicate;
+import com.tngtech.archunit.core.domain.properties.HasAnnotations;
 import com.tngtech.archunit.core.domain.properties.HasName;
 
 import static com.google.common.base.Preconditions.checkArgument;
@@ -49,13 +50,15 @@ public final class JavaPackage implements HasName {
     private final String name;
     private final String relativeName;
     private final Set<JavaClass> classes;
+    private final Optional<? extends HasAnnotations> packageInfo;
     private final Map<String, JavaPackage> subPackages;
     private Optional<JavaPackage> parent = Optional.absent();
 
     private JavaPackage(String name, Set<JavaClass> classes, Map<String, JavaPackage> subPackages) {
         this.name = checkNotNull(name);
         relativeName = name.substring(name.lastIndexOf(".") + 1);
         this.classes = ImmutableSet.copyOf(classes);
+        this.packageInfo = tryGetClassWithSimpleName("package-info");
         this.subPackages = ImmutableMap.copyOf(subPackages);
     }
 
@@ -76,6 +79,17 @@ public String getRelativeName() {
         return relativeName;
     }
 
+    @PublicAPI(usage = ACCESS)
+    public HasAnnotations getPackageInfo() {
+        return tryGetPackageInfo().getOrThrow(
+                new IllegalArgumentException(String.format("Package %s does not contain a package-info.java", getName())));
+    }
+
+    @PublicAPI(usage = ACCESS)
+    public Optional<? extends HasAnnotations> tryGetPackageInfo() {
+        return packageInfo;
+    }
+
     /**
      * @return the parent package, e.g. {@code java} for package {@code java.lang}
      */

archunit/src/test/java/com/tngtech/archunit/core/domain/JavaPackageTest.java

@@ -23,6 +23,7 @@
 import com.tngtech.archunit.core.domain.packageexamples.unrelated.AnyClass;
 import com.tngtech.archunit.core.domain.properties.HasName;
 import com.tngtech.archunit.core.importer.ClassFileImporter;
+import org.assertj.core.api.ThrowableAssert;
 import org.junit.Rule;
 import org.junit.Test;
 import org.junit.rules.ExpectedException;
@@ -36,6 +37,7 @@
 import static com.tngtech.archunit.testutil.Assertions.assertThatDependencies;
 import static com.tngtech.archunit.testutil.Assertions.assertThatPackages;
 import static java.util.regex.Pattern.quote;
+import static org.assertj.core.api.Assertions.assertThatThrownBy;
 
 public class JavaPackageTest {
     @Rule
@@ -320,6 +322,30 @@ public void has_package_dependencies_from_other_packages() {
                 .isEmpty();
     }
 
+    @Test
+    public void test_getPackageInfo() {
+        JavaPackage annotatedPackage = importPackage("packageexamples.annotated");
+        final JavaPackage notAnnotatedPackage = importPackage("packageexamples");
+
+        assertThat(annotatedPackage.getPackageInfo()).isNotNull();
+
+        assertThatThrownBy(new ThrowableAssert.ThrowingCallable() {
+            @Override
+            public void call() {
+                notAnnotatedPackage.getPackageInfo();
+            }
+        }).isInstanceOf(IllegalArgumentException.class).hasMessageContaining(".packageexamples does not contain a package-info.java");
+    }
+
+    @Test
+    public void test_tryGetPackageInfo() {
+        JavaPackage annotatedPackage = importPackage("packageexamples.annotated");
+        JavaPackage notAnnotatedPackage = importPackage("packageexamples");
+
+        assertThat(annotatedPackage.tryGetPackageInfo()).isPresent();
+        assertThat(notAnnotatedPackage.tryGetPackageInfo()).isAbsent();
+    }
+
     @Test
     public void function_GET_RELATIVE_NAME() {
         JavaPackage defaultPackage = importDefaultPackage(Object.class);

archunit/src/test/java/com/tngtech/archunit/core/domain/packageexamples/annotated/PackageLevelAnnotation.java

@@ -0,0 +1,11 @@
+package com.tngtech.archunit.core.domain.packageexamples.annotated;
+
+import java.lang.annotation.ElementType;
+import java.lang.annotation.Retention;
+import java.lang.annotation.RetentionPolicy;
+import java.lang.annotation.Target;
+
+@Retention(RetentionPolicy.RUNTIME)
+@Target(ElementType.PACKAGE)
+public @interface PackageLevelAnnotation {
+}

archunit/src/test/java/com/tngtech/archunit/core/domain/packageexamples/annotated/package-info.java

@@ -0,0 +1,2 @@
+@PackageLevelAnnotation
+package com.tngtech.archunit.core.domain.packageexamples.annotated;