Add ArchUnit to test format of loggers and Abstract classes (#10335)

* Add archunit to programatically test format and scope of loggers

* Fix use of loggers

* Update error message

* Add check for abstract class

* Test if classes with abstract in name are abstract

* Make abstract class abstract

* Rename test class

* Make logger private final

* Make logger private

modules/openapi-generator/pom.xml

@@ -334,6 +334,18 @@
             <artifactId>jackson-core</artifactId>
             <version>${jackson-version}</version>
         </dependency>
+        <dependency>
+            <groupId>com.tngtech.archunit</groupId>
+            <artifactId>archunit</artifactId>
+            <version>0.20.1</version>
+            <scope>test</scope>
+        </dependency>
+        <dependency>
+            <groupId>com.tngtech.archunit</groupId>
+            <artifactId>archunit-junit4</artifactId>
+            <version>0.20.1</version>
+            <scope>test</scope>
+        </dependency>
         <dependency>
             <groupId>org.testng</groupId>
             <artifactId>testng</artifactId>
@@ -433,6 +445,7 @@
             <artifactId>caffeine</artifactId>
             <version>2.8.1</version>
         </dependency>
+
     </dependencies>
     <repositories>
         <repository>

modules/openapi-generator/src/main/java/org/openapitools/codegen/languages/AbstractDartCodegen.java

@@ -26,7 +26,7 @@ import static org.openapitools.codegen.utils.StringUtils.*;
 
 public abstract class AbstractDartCodegen extends DefaultCodegen {
 
-    private static final Logger LOGGER = LoggerFactory.getLogger(AbstractDartCodegen.class);
+    private final Logger LOGGER = LoggerFactory.getLogger(AbstractDartCodegen.class);
 
     protected static final List<String> DEFAULT_SUPPORTED_CONTENT_TYPES = Arrays.asList(
             "application/json", "application/x-www-form-urlencoded", "multipart/form-data");

modules/openapi-generator/src/main/java/org/openapitools/codegen/languages/AspNetCoreServerCodegen.java

@@ -64,7 +64,7 @@ public class AspNetCoreServerCodegen extends AbstractCSharpCodegen {
     private String packageGuid = "{" + randomUUID().toString().toUpperCase(Locale.ROOT) + "}";
     private String userSecretsGuid = randomUUID().toString();
 
-    protected Logger LOGGER = LoggerFactory.getLogger(AspNetCoreServerCodegen.class);
+    protected final Logger LOGGER = LoggerFactory.getLogger(AspNetCoreServerCodegen.class);
 
     private boolean useSwashbuckle = true;
     protected int serverPort = 8080;

modules/openapi-generator/src/main/java/org/openapitools/codegen/languages/CSharpNetCoreClientCodegen.java

@@ -56,7 +56,7 @@ public class CSharpNetCoreClientCodegen extends AbstractCSharpCodegen {
     protected static final String TARGET_FRAMEWORK_VERSION = "targetFrameworkVersion";
 
     @SuppressWarnings({"hiding"})
-    private static final Logger LOGGER = LoggerFactory.getLogger(CSharpClientCodegen.class);
+    private final Logger LOGGER = LoggerFactory.getLogger(CSharpClientCodegen.class);
     private static final List<FrameworkStrategy> frameworkStrategies = Arrays.asList(
             FrameworkStrategy.NETSTANDARD_1_3,
             FrameworkStrategy.NETSTANDARD_1_4,
@@ -973,6 +973,9 @@ public class CSharpNetCoreClientCodegen extends AbstractCSharpCodegen {
     // https://docs.microsoft.com/en-us/dotnet/standard/net-standard
     @SuppressWarnings("Duplicates")
     private static abstract class FrameworkStrategy {
+
+        private final Logger LOGGER = LoggerFactory.getLogger(CSharpClientCodegen.class);
+
         static FrameworkStrategy NETSTANDARD_1_3 = new FrameworkStrategy("netstandard1.3", ".NET Standard 1.3 compatible", "netcoreapp2.0") {
         };
         static FrameworkStrategy NETSTANDARD_1_4 = new FrameworkStrategy("netstandard1.4", ".NET Standard 1.4 compatible", "netcoreapp2.0") {

modules/openapi-generator/src/main/java/org/openapitools/codegen/languages/CppQtAbstractCodegen.java

@@ -13,7 +13,8 @@ import org.slf4j.LoggerFactory;
 import java.io.File;
 import java.util.*;
 
-public class CppQtAbstractCodegen extends AbstractCppCodegen implements CodegenConfig {
+public abstract class CppQtAbstractCodegen extends AbstractCppCodegen implements CodegenConfig {
+
     private final Logger LOGGER = LoggerFactory.getLogger(CppQtAbstractCodegen.class);
     protected final String PREFIX = "OAI";
     protected String apiVersion = "1.0.0";

modules/openapi-generator/src/main/java/org/openapitools/codegen/languages/CppRestbedServerCodegen.java

@@ -23,7 +23,6 @@ import org.apache.commons.lang3.StringUtils;
 import org.openapitools.codegen.*;
 import org.openapitools.codegen.meta.features.*;
 import org.openapitools.codegen.utils.ModelUtils;
-import org.slf4j.LoggerFactory;
 
 import java.io.File;
 import java.util.*;
@@ -33,8 +32,6 @@ import static org.openapitools.codegen.utils.StringUtils.camelize;
 
 public class CppRestbedServerCodegen extends AbstractCppCodegen {
 
-    private static final org.slf4j.Logger LOGGER = LoggerFactory.getLogger(CppRestbedServerCodegen.class);
-
     public static final String DECLSPEC = "declspec";
     public static final String DEFAULT_INCLUDE = "defaultInclude";
 

modules/openapi-generator/src/main/java/org/openapitools/codegen/languages/CppTinyClientCodegen.java

@@ -36,7 +36,7 @@ import org.slf4j.LoggerFactory;
 public class CppTinyClientCodegen extends AbstractCppCodegen implements CodegenConfig {
     public static final String PROJECT_NAME = "TinyClient";
 
-    static final Logger LOGGER = LoggerFactory.getLogger(CppTinyClientCodegen.class);
+    final Logger LOGGER = LoggerFactory.getLogger(CppTinyClientCodegen.class);
 
     public static final String MICROCONTROLLER = "controller";
     public static final String rootFolder = "";

modules/openapi-generator/src/main/java/org/openapitools/codegen/languages/DartDioNextClientCodegen.java

@@ -37,7 +37,7 @@ import static org.openapitools.codegen.utils.StringUtils.underscore;
 
 public class DartDioNextClientCodegen extends AbstractDartCodegen {
 
-    private static final Logger LOGGER = LoggerFactory.getLogger(DartDioNextClientCodegen.class);
+    private final Logger LOGGER = LoggerFactory.getLogger(DartDioNextClientCodegen.class);
 
     public static final String DATE_LIBRARY = "dateLibrary";
     public static final String DATE_LIBRARY_CORE = "core";

modules/openapi-generator/src/main/java/org/openapitools/codegen/languages/FsharpGiraffeServerCodegen.java

@@ -50,7 +50,7 @@ public class FsharpGiraffeServerCodegen extends AbstractFSharpCodegen {
     private String packageGuid = "{" + randomUUID().toString().toUpperCase(Locale.ROOT) + "}";
 
     @SuppressWarnings("hiding")
-    protected Logger LOGGER = LoggerFactory.getLogger(FsharpGiraffeServerCodegen.class);
+    protected final Logger LOGGER = LoggerFactory.getLogger(FsharpGiraffeServerCodegen.class);
 
     private boolean useSwashbuckle = false;
     protected int serverPort = 8080;

modules/openapi-generator/src/main/java/org/openapitools/codegen/languages/GoEchoServerCodegen.java

@@ -17,19 +17,17 @@
 package org.openapitools.codegen.languages;
 
 import org.openapitools.codegen.*;
-
-import java.io.File;
-import java.util.*;
-
-import org.openapitools.codegen.meta.features.*;
 import org.openapitools.codegen.meta.GeneratorMetadata;
 import org.openapitools.codegen.meta.Stability;
-import org.slf4j.Logger;
+import org.openapitools.codegen.meta.features.*;
-import org.slf4j.LoggerFactory;
+
+import java.io.File;
+import java.util.Arrays;
+import java.util.EnumSet;
+import java.util.List;
+import java.util.Map;
 
 public class GoEchoServerCodegen extends AbstractGoCodegen {
-    static final Logger LOGGER = LoggerFactory.getLogger(GoEchoServerCodegen.class);
-
     protected String apiVersion = "1.0.0";
     protected int serverPort = 8080;
     protected String projectName = "openapi-go-echo-server";

modules/openapi-generator/src/main/java/org/openapitools/codegen/languages/HaskellYesodServerCodegen.java

@@ -46,7 +46,7 @@ public class HaskellYesodServerCodegen extends DefaultCodegen implements Codegen
 
     private static final Pattern LEADING_UNDERSCORE = Pattern.compile("^_+");
 
-    static final Logger LOGGER = LoggerFactory.getLogger(HaskellYesodServerCodegen.class);
+    private final Logger LOGGER = LoggerFactory.getLogger(HaskellYesodServerCodegen.class);
 
     protected String projectName;
     protected String apiModuleName;

modules/openapi-generator/src/main/java/org/openapitools/codegen/languages/KotlinSpringServerCodegen.java

@@ -43,7 +43,7 @@ import static org.openapitools.codegen.utils.StringUtils.camelize;
 public class KotlinSpringServerCodegen extends AbstractKotlinCodegen
         implements BeanValidationFeatures {
 
-    private static Logger LOGGER =
+    private final Logger LOGGER =
             LoggerFactory.getLogger(KotlinSpringServerCodegen.class);
 
     private static final HashSet<String> VARIABLE_RESERVED_WORDS =

modules/openapi-generator/src/main/java/org/openapitools/codegen/languages/KtormSchemaCodegen.java

@@ -39,7 +39,7 @@ import static org.openapitools.codegen.utils.StringUtils.*;
 
 @SuppressWarnings("unchecked")
 public class KtormSchemaCodegen extends AbstractKotlinCodegen {
-    static Logger LOGGER = LoggerFactory.getLogger(KtormSchemaCodegen.class);
+    private final Logger LOGGER = LoggerFactory.getLogger(KtormSchemaCodegen.class);
 
     public static final String VENDOR_EXTENSION_SCHEMA = "x-ktorm-schema";
     public static final String DEFAULT_DATABASE_NAME = "defaultDatabaseName";

modules/openapi-generator/src/main/java/org/openapitools/codegen/languages/ScalaAkkaClientCodegen.java

@@ -51,7 +51,7 @@ public class ScalaAkkaClientCodegen extends AbstractScalaCodegen implements Code
     protected boolean removeOAuthSecurities = true;
 
     @SuppressWarnings("hiding")
-    protected Logger LOGGER = LoggerFactory.getLogger(ScalaAkkaClientCodegen.class);
+    protected final Logger LOGGER = LoggerFactory.getLogger(ScalaAkkaClientCodegen.class);
 
     public ScalaAkkaClientCodegen() {
         super();

modules/openapi-generator/src/main/java/org/openapitools/codegen/languages/ScalaAkkaHttpServerCodegen.java

@@ -50,7 +50,7 @@ public class ScalaAkkaHttpServerCodegen extends AbstractScalaCodegen implements
     public static final String GENERATE_AS_MANAGED_SOURCES_DESC = "Resulting files cab be used as managed resources. No build files or default controllers will be generated";
     public static final boolean DEFAULT_GENERATE_AS_MANAGED_SOURCES = false;
 
-    static final Logger LOGGER = LoggerFactory.getLogger(ScalaAkkaHttpServerCodegen.class);
+    final Logger LOGGER = LoggerFactory.getLogger(ScalaAkkaHttpServerCodegen.class);
 
     public CodegenType getTag() {
         return CodegenType.SERVER;
@@ -305,7 +305,7 @@ public class ScalaAkkaHttpServerCodegen extends AbstractScalaCodegen implements
         .put("String", "Segment")
     .build();
 
-    protected static void addPathMatcher(CodegenOperation codegenOperation) {
+    protected void addPathMatcher(CodegenOperation codegenOperation) {
         LinkedList<String> allPaths = new LinkedList<>(Arrays.asList(codegenOperation.path.split("/")));
         allPaths.removeIf(""::equals);
 

modules/openapi-generator/src/main/java/org/openapitools/codegen/languages/WsdlSchemaCodegen.java

@@ -18,35 +18,20 @@ package org.openapitools.codegen.languages;
 
 import io.swagger.v3.oas.models.OpenAPI;
 import io.swagger.v3.oas.models.info.Info;
+import org.openapitools.codegen.*;
+import org.openapitools.codegen.meta.GeneratorMetadata;
+import org.openapitools.codegen.meta.Stability;
 
 import java.io.File;
 import java.text.Normalizer;
-import java.util.List;
 import java.util.ArrayList;
+import java.util.List;
 import java.util.Locale;
 import java.util.Map;
 
-import org.openapitools.codegen.CliOption;
-import org.openapitools.codegen.CodegenConfig;
-import org.openapitools.codegen.CodegenModel;
-import org.openapitools.codegen.CodegenOperation;
-import org.openapitools.codegen.CodegenParameter;
-import org.openapitools.codegen.CodegenProperty;
-import org.openapitools.codegen.CodegenType;
-import org.openapitools.codegen.DefaultCodegen;
-import org.openapitools.codegen.meta.GeneratorMetadata;
-import org.openapitools.codegen.meta.Stability;
-import org.openapitools.codegen.meta.features.*;
-import org.openapitools.codegen.SupportingFile;
-
-import org.slf4j.Logger;
-import org.slf4j.LoggerFactory;
-
 public class WsdlSchemaCodegen extends DefaultCodegen implements CodegenConfig {
     public static final String PROJECT_NAME = "projectName";
 
-    static final Logger LOGGER = LoggerFactory.getLogger(WsdlSchemaCodegen.class);
-
     public CodegenType getTag() {
         return CodegenType.SCHEMA;
     }

modules/openapi-generator/src/test/java/org/openapitools/codegen/ArchUnitRulesTest.java

@@ -0,0 +1,52 @@
+package org.openapitools.codegen;
+
+import com.tngtech.archunit.core.domain.JavaClasses;
+import com.tngtech.archunit.core.domain.JavaModifier;
+import com.tngtech.archunit.core.importer.ClassFileImporter;
+import com.tngtech.archunit.lang.ArchRule;
+import org.junit.Test;
+import org.slf4j.Logger;
+
+import static com.tngtech.archunit.lang.syntax.ArchRuleDefinition.*;
+
+public class ArchUnitRulesTest {
+
+    @Test
+    public void testLoggersAreNotPublicFinalAndNotStatic() {
+        final JavaClasses importedClasses = new ClassFileImporter()
+                .importPackages("org.openapitools.codegen.languages");
+
+        ArchUnitRulesTest.LOGGERS_SHOULD_BE_NOT_PUBLIC_NOT_STATIC_AND_FINAL.check(importedClasses);
+    }
+
+    @Test
+    public void abstractClassesAreAbstract() {
+        final JavaClasses importedClasses = new ClassFileImporter()
+                .importPackages("org.openapitools.codegen.languages");
+
+        ArchUnitRulesTest.ABSTRACT_CLASS_MUST_BE_ABSTRACT.check(importedClasses);
+    }
+
+    /**
+     * Making loggers not static decreases memory consumption when running generator:
+     * https://github.com/OpenAPITools/openapi-generator/pull/8799
+     */
+    public static final ArchRule LOGGERS_SHOULD_BE_NOT_PUBLIC_NOT_STATIC_AND_FINAL =
+            fields()
+            .that()
+            .haveRawType(Logger.class)
+            .should().notBePublic()
+            .andShould().notBeStatic()
+            .andShould().beFinal()
+            .because("Code generators are most often used once per program lifetime, " +
+                    "so making them all static will cause higher memory consumption. " +
+                    "See PR #8799");
+
+
+    public static final ArchRule ABSTRACT_CLASS_MUST_BE_ABSTRACT =
+            classes()
+            .that()
+            .haveSimpleNameContaining("Abstract").or().haveSimpleNameContaining("abstract")
+            .should()
+            .haveModifier(JavaModifier.ABSTRACT);
+}