add method JavaClass.getTransitiveDependenciesFromSelf

Signed-off-by: Manfred Hanke <[email protected]>

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

@@ -1031,6 +1031,17 @@ public Set<Dependency> getDirectDependenciesFromSelf() {
         return javaClassDependencies.getDirectDependenciesFromClass();
     }
 
+    /**
+     * Returns the transitive closure of all dependencies originating from this class, i.e. its direct dependencies
+     * and the dependencies from all imported target classes.
+     * @return all transitive dependencies (including direct dependencies) from this class
+     * @see #getDirectDependenciesFromSelf()
+     */
+    @PublicAPI(usage = ACCESS)
+    public Set<Dependency> getTransitiveDependenciesFromSelf() {
+        return JavaClassTransitiveDependencies.findTransitiveDependenciesFrom(this);
+    }
+
     /**
      * Like {@link #getDirectDependenciesFromSelf()}, but instead returns all dependencies where this class
      * is target.

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

@@ -0,0 +1,47 @@
+/*
+ * Copyright 2014-2020 TNG Technology Consulting GmbH
+ *
+ * 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.
+ */
+package com.tngtech.archunit.core.domain;
+
+import com.google.common.collect.ImmutableSet;
+
+import java.util.HashSet;
+import java.util.Set;
+
+class JavaClassTransitiveDependencies {
+    private JavaClassTransitiveDependencies() {
+    }
+
+    static Set<Dependency> findTransitiveDependenciesFrom(JavaClass javaClass) {
+        ImmutableSet.Builder<Dependency> transitiveDependencies = ImmutableSet.builder();
+        Set<JavaClass> analyzedClasses = new HashSet<>();  // to avoid infinite recursion for cyclic dependencies
+        addTransitiveDependenciesFrom(javaClass, transitiveDependencies, analyzedClasses);
+        return transitiveDependencies.build();
+    }
+
+    private static void addTransitiveDependenciesFrom(JavaClass javaClass, ImmutableSet.Builder<Dependency> transitiveDependencies, Set<JavaClass> analyzedClasses) {
+        analyzedClasses.add(javaClass);  // currently being analyzed
+        Set<JavaClass> targetClassesToRecurse = new HashSet<>();
+        for (Dependency dependency : javaClass.getDirectDependenciesFromSelf()) {
+            transitiveDependencies.add(dependency);
+            targetClassesToRecurse.add(dependency.getTargetClass().getBaseComponentType());
+        }
+        for (JavaClass targetClass : targetClassesToRecurse) {
+            if (!analyzedClasses.contains(targetClass)) {
+                addTransitiveDependenciesFrom(targetClass, transitiveDependencies, analyzedClasses);
+            }
+        }
+    }
+}

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

@@ -0,0 +1,145 @@
+package com.tngtech.archunit.core.domain;
+
+import com.tngtech.archunit.core.importer.ClassFileImporter;
+import org.junit.Test;
+
+import static com.tngtech.archunit.testutil.Assertions.assertThatDependencies;
+
+public class JavaClassTransitiveDependenciesTest {
+
+    static class AcyclicGraph {
+        static class A {
+            B b;
+            C[][] c;
+        }
+
+        static class B {
+            Integer i;
+        }
+
+        static class C {
+            D d;
+        }
+
+        static class D {
+            String s;
+        }
+    }
+
+    @Test
+    public void findsTransitiveDependenciesInAcyclicGraph() {
+        Class<?> a = AcyclicGraph.A.class;
+        Class<?> b = AcyclicGraph.B.class;
+        Class<?> c = AcyclicGraph.C.class;
+        Class<?> d = AcyclicGraph.D.class;
+        JavaClasses classes = new ClassFileImporter().importClasses(a, b, c, d);
+        Class<?> cArray = AcyclicGraph.C[][].class;
+
+        // @formatter:off
+        assertThatDependencies(classes.get(a).getTransitiveDependenciesFromSelf())
+                .contain(a, Object.class)
+                .contain(a, b)
+                    .contain(b, Object.class)
+                    .contain(b, Integer.class)
+                .contain(a, cArray)
+                    .contain(c, Object.class)
+                    .contain(c, d)
+                        .contain(d, Object.class)
+                        .contain(d, String.class);
+
+        assertThatDependencies(classes.get(b).getTransitiveDependenciesFromSelf())
+                .contain(b, Object.class)
+                .contain(b, Integer.class);
+
+        assertThatDependencies(classes.get(c).getTransitiveDependenciesFromSelf())
+                .contain(c, Object.class)
+                .contain(c, d)
+                    .contain(d, Object.class)
+                    .contain(d, String.class);
+        // @formatter:on
+    }
+
+
+    static class CyclicGraph {
+        static class A {
+            B b;
+            C[][] c;
+            D d;
+        }
+
+        static class B {
+            Integer i;
+        }
+
+        static class C {
+            A a;
+        }
+
+        static class D {
+            E e;
+        }
+
+        static class E {
+            A a;
+            String s;
+        }
+    }
+
+    @Test
+    public void findsTransitiveDependenciesInCyclicGraph() {
+        Class<?> a = CyclicGraph.A.class;
+        Class<?> b = CyclicGraph.B.class;
+        Class<?> c = CyclicGraph.C.class;
+        Class<?> d = CyclicGraph.D.class;
+        Class<?> e = CyclicGraph.E.class;
+        JavaClasses classes = new ClassFileImporter().importClasses(a, b, c, d, e);
+        Class<?> cArray = CyclicGraph.C[][].class;
+
+        // @formatter:off
+        assertThatDependencies(classes.get(a).getTransitiveDependenciesFromSelf())
+                .contain(a, Object.class)
+                .contain(a, b)
+                    .contain(b, Object.class)
+                    .contain(b, Integer.class)
+                .contain(a, cArray)
+                    .contain(c, Object.class)
+                    .contain(c, a)
+                .contain(a, d)
+                    .contain(d, Object.class)
+                    .contain(d, e)
+                        .contain(e, Object.class)
+                        .contain(e, a)
+                        .contain(e, String.class);
+
+        assertThatDependencies(classes.get(c).getTransitiveDependenciesFromSelf())
+                .contain(c, Object.class)
+                .contain(c, a)
+                    .contain(a, Object.class)
+                    .contain(a, b)
+                        .contain(b, Object.class)
+                        .contain(b, Integer.class)
+                    .contain(a, cArray)
+                    .contain(a, d)
+                        .contain(d, Object.class)
+                        .contain(d, e)
+                            .contain(e, Object.class)
+                            .contain(e, a)
+                            .contain(e, String.class);
+
+        assertThatDependencies(classes.get(d).getTransitiveDependenciesFromSelf())
+                .contain(d, Object.class)
+                .contain(d, e)
+                    .contain(e, Object.class)
+                    .contain(e, a)
+                        .contain(a, Object.class)
+                        .contain(a, b)
+                            .contain(b, Object.class)
+                            .contain(b, Integer.class)
+                        .contain(a, cArray)
+                            .contain(c, Object.class)
+                            .contain(c, a)
+                        .contain(a, d)
+                    .contain(e, String.class);
+        // @formatter:on
+    }
+}