moditect#27 WIP Adding cycle detection to architecture validation

javac-plugin/src/main/java/org/moditect/deptective/internal/handler/PackageReferenceValidator.java

@@ -18,6 +18,7 @@
 import java.io.IOException;
 import java.io.Writer;
 import java.util.HashMap;
+import java.util.List;
 import java.util.Map;
 import java.util.stream.Collectors;
 
@@ -26,6 +27,8 @@
 import javax.tools.StandardLocation;
 
 import org.moditect.deptective.internal.export.DotSerializer;
+import org.moditect.deptective.internal.graph.Cycle;
+import org.moditect.deptective.internal.graph.GraphUtils;
 import org.moditect.deptective.internal.log.DeptectiveMessages;
 import org.moditect.deptective.internal.log.Log;
 import org.moditect.deptective.internal.model.Component;
@@ -50,12 +53,11 @@ public class PackageReferenceValidator implements PackageReferenceHandler {
     private final PackageDependencies allowedPackageDependencies;
     private final JavaFileManager jfm;
     private final ReportingPolicy reportingPolicy;
-    private boolean createDotFile;
     private final ReportingPolicy unconfiguredPackageReportingPolicy;
     private final Map<String, Boolean> reportedUnconfiguredPackages;
-
     private final PackageDependencies.Builder actualPackageDependencies;
 
+    private boolean createDotFile;
     private String currentPackageName;
     private Component currentComponent;
 
@@ -79,6 +81,16 @@ public boolean configIsValid() {
             return false;
         }
 
+        List<Cycle<Component>> cycles = GraphUtils.detectCycles(allowedPackageDependencies.getComponents());
+
+        if (!cycles.isEmpty()) {
+            String cyclesAsString = "- " + cycles.stream()
+                    .map(Cycle::toString)
+                    .collect(Collectors.joining("," + System.lineSeparator() + "- "));
+
+            log.report(ReportingPolicy.ERROR, DeptectiveMessages.CYCLE_IN_ARCHITECTURE, cyclesAsString);
+        }
+
         return true;
     }
 

javac-plugin/src/main/java/org/moditect/deptective/internal/log/DeptectiveMessages.java

@@ -29,6 +29,7 @@ public class DeptectiveMessages extends ListResourceBundle {
     public static final String GENERATED_CONFIG = "deptective.generatedconfig";
     public static final String GENERATED_DOT_REPRESENTATION = "deptective.dotrepresentation";
     public static final String PACKAGE_CONTAINED_IN_MULTIPLE_COMPONENTS = "deptective.packageinmultiplecomponents";
+    public static final String CYCLE_IN_ARCHITECTURE = "deptective.cycleinarchitecture";
 
     @Override
     protected final Object[][] getContents() {
@@ -43,6 +44,9 @@ protected final Object[][] getContents() {
                         "Created DOT file representing the Deptective configuration at {0}" },
                 { ERROR_PREFIX + PACKAGE_CONTAINED_IN_MULTIPLE_COMPONENTS,
                         "Multiple components match package {1}: {0}" },
+                { ERROR_PREFIX + CYCLE_IN_ARCHITECTURE,
+                        "Architecture model contains cycle(s) between these components: " + System.lineSeparator()
+                                + "{0}" },
         };
     }
 

javac-plugin/src/main/java/org/moditect/deptective/internal/model/Component.java

@@ -22,6 +22,9 @@
 import java.util.Map;
 import java.util.Set;
 
+import org.moditect.deptective.internal.graph.Dependency;
+import org.moditect.deptective.internal.graph.Node;
+
 /**
  * Describes a component, a set of packages identified by one more naming patterns.
  * <p>
@@ -30,7 +33,7 @@
  *
  * @author Gunnar Morling
  */
-public class Component {
+public class Component implements Node<Component> {
 
     public static class Builder {
 
@@ -122,4 +125,51 @@ public Map<String, ReadKind> getReads() {
     public String toString() {
         return name + " { contained=" + contained + ", reads=" + reads + "] }";
     }
+
+    @Override
+    public String asShortString() {
+        return name;
+    }
+
+    @Override
+    public Dependency<Component> getOutgoingDependencyTo(Component node) {
+        return reads.entrySet()
+                .stream()
+                .filter(e -> e.getKey().equals(node.getName()))
+                .map(e -> new Dependency<Component>(Component.builder(e.getKey()).build(), 1))
+                .findFirst()
+                .orElse(null);
+    }
+
+    @Override
+    public boolean hasOutgoingDependencies() {
+        return !reads.isEmpty();
+    }
+
+    @Override
+    public int hashCode() {
+        final int prime = 31;
+        int result = 1;
+        result = prime * result + ((name == null) ? 0 : name.hashCode());
+        return result;
+    }
+
+    @Override
+    public boolean equals(Object obj) {
+        if (this == obj)
+            return true;
+        if (obj == null)
+            return false;
+        if (getClass() != obj.getClass())
+            return false;
+        Component other = (Component) obj;
+        if (name == null) {
+            if (other.name != null)
+                return false;
+        }
+        else if (!name.equals(other.name))
+            return false;
+        return true;
+    }
+
 }

javac-plugin/src/main/java/org/moditect/deptective/internal/model/PackageDependencies.java

@@ -142,4 +142,8 @@ public boolean isWhitelisted(String packageName) {
                 .findFirst()
                 .isPresent();
     }
+
+    public Iterable<Component> getComponents() {
+        return components;
+    }
 }

javac-plugin/src/test/java/org/moditect/deptective/plugintest/cycle/CycleTest.java

@@ -0,0 +1,50 @@
+/**
+ *  Copyright 2019 The ModiTect authors
+ *
+ *  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 org.moditect.deptective.plugintest.cycle;
+
+import static com.google.testing.compile.CompilationSubject.assertThat;
+
+import org.junit.Test;
+import org.moditect.deptective.plugintest.PluginTestBase;
+import org.moditect.deptective.plugintest.cycle.bar.Bar;
+import org.moditect.deptective.plugintest.cycle.baz.Baz;
+import org.moditect.deptective.plugintest.cycle.foo.Foo;
+import org.moditect.deptective.plugintest.cycle.qux.Qux;
+
+import com.google.testing.compile.Compilation;
+import com.google.testing.compile.Compiler;
+
+public class CycleTest extends PluginTestBase {
+
+    @Test
+    public void shouldDetectCyclesInArchitectureModel() {
+        Compilation compilation = Compiler.javac()
+                .withOptions(
+                        "-Xplugin:Deptective",
+                        getConfigFileOption()
+                )
+                .compile(
+                        forTestClass(Foo.class),
+                        forTestClass(Bar.class),
+                        forTestClass(Baz.class),
+                        forTestClass(Qux.class)
+                );
+
+        assertThat(compilation).failed();
+        assertThat(compilation).hadErrorContaining("Architecture model contains cycle(s) between these components:");
+        assertThat(compilation).hadErrorContaining("  - bar, baz, foo, qux");
+    }
+}

javac-plugin/src/test/java/org/moditect/deptective/plugintest/cycle/bar/Bar.java

@@ -0,0 +1,25 @@
+/**
+ *  Copyright 2019 The ModiTect authors
+ *
+ *  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 org.moditect.deptective.plugintest.cycle.bar;
+
+import org.moditect.deptective.plugintest.cycle.baz.Baz;
+import org.moditect.deptective.plugintest.cycle.qux.Qux;
+
+public class Bar {
+
+    Baz baz;
+    Qux qux;
+}

javac-plugin/src/test/java/org/moditect/deptective/plugintest/cycle/baz/Baz.java

@@ -0,0 +1,23 @@
+/**
+ *  Copyright 2019 The ModiTect authors
+ *
+ *  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 org.moditect.deptective.plugintest.cycle.baz;
+
+import org.moditect.deptective.plugintest.cycle.foo.Foo;
+
+public class Baz {
+
+    private Foo foo;
+}

javac-plugin/src/test/java/org/moditect/deptective/plugintest/cycle/foo/Foo.java

@@ -0,0 +1,23 @@
+/**
+ *  Copyright 2019 The ModiTect authors
+ *
+ *  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 org.moditect.deptective.plugintest.cycle.foo;
+
+import org.moditect.deptective.plugintest.cycle.bar.Bar;
+
+public class Foo {
+
+    private final Bar bar = new Bar();
+}

javac-plugin/src/test/java/org/moditect/deptective/plugintest/cycle/qux/Qux.java

@@ -0,0 +1,23 @@
+/**
+ *  Copyright 2019 The ModiTect authors
+ *
+ *  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 org.moditect.deptective.plugintest.cycle.qux;
+
+import org.moditect.deptective.plugintest.cycle.bar.Bar;
+
+public class Qux {
+
+    Bar bar;
+}

javac-plugin/src/test/java/org/moditect/deptective/plugintest/whitelist/bar/Bar.java

@@ -15,6 +15,9 @@
  */
 package org.moditect.deptective.plugintest.whitelist.bar;
 
+import org.moditect.deptective.plugintest.whitelist.foo.Foo;
+
 public class Bar {
 
+    Foo f;
 }

javac-plugin/src/test/resources/org/moditect/deptective/plugintest/cycle/deptective.json

@@ -0,0 +1,24 @@
+{
+    "components" : [
+        {
+            "name" : "foo",
+            "contains" : [ "org.moditect.deptective.plugintest.cycle.foo" ],
+            "reads" : [ "bar" ]
+        },
+        {
+            "name" : "bar",
+            "contains" : [ "org.moditect.deptective.plugintest.cycle.bar" ],
+            "reads" : [ "baz", "qux" ]
+        },
+        {
+            "name" : "baz",
+            "contains" : [ "org.moditect.deptective.plugintest.cycle.baz" ],
+            "reads" : [ "foo" ]
+        },
+        {
+            "name" : "qux",
+            "contains" : [ "org.moditect.deptective.plugintest.cycle.qux" ],
+            "reads" : [ "bar" ]
+        }
+    ]
+}