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charphicharphi
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Add trait annotation
1 parent df5554e commit 3d903ef

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Lines changed: 244 additions & 28 deletions

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‎CHANGELOG.md‎

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@@ -7,6 +7,10 @@ and this project adheres to [Semantic Versioning](https://semver.org/spec/v2.0.0
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## [Unreleased]
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### Added
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- Add trait annotation [#351](https://github.com/nbbrd/java-design-util/issues/351)
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### Changed
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- Migrate OSSRH to Central Portal

‎java-design-annotation/src/main/java/nbbrd/design/Trait.java‎

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package nbbrd.design;
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import java.lang.annotation.*;
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/**
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* This annotation indicates that the class is a trait.
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* Traits are used to define reusable behaviors that can be mixed into classes.
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* They are typically used in a design context to enhance the functionality of classes without using inheritance.
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*
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* @see <a href="https://en.wikipedia.org/wiki/Trait_(computer_programming)">Trait (computer programming)</a>
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*/
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@Target({ElementType.TYPE})
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@Retention(RetentionPolicy.SOURCE)
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@Documented
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public @interface Trait {
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}

‎java-design-processor/src/main/java/internal/nbbrd/design/ClassNameConstantProcessor.java‎

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@@ -30,7 +30,7 @@
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import java.util.Set;
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import static internal.nbbrd.design.proc.Rule.is;
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import static internal.nbbrd.design.proc.Rule.of;
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import static internal.nbbrd.design.proc.Rule.it;
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import static javax.lang.model.element.Modifier.FINAL;
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import static javax.lang.model.element.Modifier.STATIC;
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@@ -61,5 +61,5 @@ private static boolean hasClassName(VariableElement field) {
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.and(is(STATIC))
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.and(is(FINAL))
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.and(is(String.class))
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.and(of(ClassNameConstantProcessor::hasClassName, "'%s' should represent the full name of its enclosing class"));
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.and(it(ClassNameConstantProcessor::hasClassName, "'%s' should represent the full name of its enclosing class"));
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}

‎java-design-processor/src/main/java/internal/nbbrd/design/DirectImplProcessor.java‎

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@@ -32,7 +32,7 @@
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import static internal.nbbrd.design.proc.Elements2.fieldsIn;
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import static internal.nbbrd.design.proc.Rule.is;
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import static internal.nbbrd.design.proc.Rule.of;
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import static internal.nbbrd.design.proc.Rule.it;
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import static javax.lang.model.element.Modifier.FINAL;
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/**
@@ -52,15 +52,15 @@ public boolean process(Set<? extends TypeElement> annotations, RoundEnvironment
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return Processing.of(IS_DIRECT_IMPL).process(annotations, roundEnv, processingEnv);
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}
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55-
private static boolean extendAtLeastOneInterface(TypeElement type) {
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private static boolean extendsAtLeastOneInterface(TypeElement type) {
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return !type.getInterfaces().isEmpty();
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}
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59-
private static boolean doNotExtendClass(TypeElement type) {
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private static boolean doesNotExtendClass(TypeElement type) {
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return type.getSuperclass().toString().equals(Object.class.getName());
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}
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private static boolean doNotContainPublicVars(TypeElement type) {
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private static boolean doesNotContainPublicVars(TypeElement type) {
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return fieldsIn(type).noneMatch(DirectImplProcessor::isVariableNotStaticButPublic);
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}
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@@ -72,7 +72,7 @@ private static boolean isVariableNotStaticButPublic(VariableElement e) {
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private static final Rule<TypeElement> IS_DIRECT_IMPL = Rule.on(TypeElement.class)
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.and(is(FINAL))
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.and(of(DirectImplProcessor::doNotExtendClass, "'%s' may not extend another class"))
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.and(of(DirectImplProcessor::doNotContainPublicVars, "'%s' may not contain public vars"))
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.and(of(DirectImplProcessor::extendAtLeastOneInterface, "'%s' must extend at least one interface"));
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.and(it(DirectImplProcessor::doesNotExtendClass, "'%s' may not extend another class"))
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.and(it(DirectImplProcessor::doesNotContainPublicVars, "'%s' may not contain public vars"))
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.and(it(DirectImplProcessor::extendsAtLeastOneInterface, "'%s' must extend at least one interface"));
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}

‎java-design-processor/src/main/java/internal/nbbrd/design/ImmutableProcessor.java‎

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@@ -33,6 +33,7 @@
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import static internal.nbbrd.design.proc.Elements2.fieldsIn;
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import static internal.nbbrd.design.proc.Rule.is;
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import static internal.nbbrd.design.proc.Rule.it;
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import static javax.lang.model.element.Modifier.*;
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/**
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return Processing.of(IS_IMMUTABLE).process(annotations, roundEnv, processingEnv);
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}
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55-
private static boolean areFieldsFinalOrLazy(TypeElement type) {
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private static boolean hasFieldsFinalOrLazy(TypeElement type) {
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boolean lazy = type.getAnnotation(Immutable.class).lazy();
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return getNonStaticFields(type).allMatch(field -> field.getModifiers().contains(FINAL) || (lazy && field.getModifiers().contains(VOLATILE)));
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}
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60-
private static boolean areFieldsPrivate(TypeElement type) {
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private static boolean hasFieldsPrivate(TypeElement type) {
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return getNonStaticFields(type).allMatch(field -> field.getModifiers().contains(PRIVATE));
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}
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@@ -70,13 +71,9 @@ private static Stream<VariableElement> getNonStaticFields(TypeElement type) {
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return fieldsIn(type).filter(field -> !field.getModifiers().contains(STATIC));
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}
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private static final Rule<TypeElement> ARE_FIELDS_FINAL_OR_LAZY = Rule.of(ImmutableProcessor::areFieldsFinalOrLazy, "Fields of '%s' must be final or lazy");
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private static final Rule<TypeElement> ARE_FIELDS_PRIVATE = Rule.of(ImmutableProcessor::areFieldsPrivate, "Fields of '%s' must be private");
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private static final Rule<TypeElement> HAS_LAZY_FIELD_IF_LAZY = Rule.of(ImmutableProcessor::hasLazyFieldIfLazy, "'%s' must have at least one lazy field");
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private static final Rule<TypeElement> IS_IMMUTABLE = Rule.on(TypeElement.class)
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.and(is(FINAL))
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.and(ARE_FIELDS_FINAL_OR_LAZY)
80-
.and(ARE_FIELDS_PRIVATE)
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.and(HAS_LAZY_FIELD_IF_LAZY);
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.and(it(ImmutableProcessor::hasFieldsFinalOrLazy, "Fields of '%s' must be final or lazy"))
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.and(it(ImmutableProcessor::hasFieldsPrivate, "Fields of '%s' must be private"))
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.and(it(ImmutableProcessor::hasLazyFieldIfLazy, "'%s' must have at least one lazy field"));
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}

‎java-design-processor/src/main/java/internal/nbbrd/design/TraitProcessor.java‎

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/*
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* Copyright 2018 National Bank of Belgium
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*
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* Licensed under the EUPL, Version 1.1 or - as soon they will be approved
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* by the European Commission - subsequent versions of the EUPL (the "Licence");
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* You may not use this work except in compliance with the Licence.
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* You may obtain a copy of the Licence at:
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*
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* http://ec.europa.eu/idabc/eupl
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*
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* Unless required by applicable law or agreed to in writing, software
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* distributed under the Licence is distributed on an "AS IS" basis,
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* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
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* See the Licence for the specific language governing permissions and
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* limitations under the Licence.
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*/
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package internal.nbbrd.design;
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import internal.nbbrd.design.proc.Elements2;
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import internal.nbbrd.design.proc.Processing;
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import internal.nbbrd.design.proc.Rule;
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import nbbrd.service.ServiceProvider;
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import javax.annotation.processing.AbstractProcessor;
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import javax.annotation.processing.Processor;
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import javax.annotation.processing.RoundEnvironment;
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import javax.annotation.processing.SupportedAnnotationTypes;
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import javax.lang.model.SourceVersion;
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import javax.lang.model.element.TypeElement;
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import java.util.Set;
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import static internal.nbbrd.design.proc.Rule.*;
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import static javax.lang.model.element.ElementKind.INTERFACE;
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/**
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* @author Philippe Charles
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*/
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@ServiceProvider(Processor.class)
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@SupportedAnnotationTypes("nbbrd.design.Trait")
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public final class TraitProcessor extends AbstractProcessor {
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@Override
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public SourceVersion getSupportedSourceVersion() {
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return SourceVersion.latestSupported();
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}
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@Override
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public boolean process(Set<? extends TypeElement> annotations, RoundEnvironment roundEnv) {
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return Processing.of(IS_TRAIT).process(annotations, roundEnv, processingEnv);
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}
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private static boolean hasAtLeastOneMethod(TypeElement type) {
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return Elements2.methodsIn(type).findAny().isPresent();
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}
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static boolean isValidName(String name) {
57+
return name.endsWith("ble") || name.startsWith("Has");
58+
}
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private static final Rule<TypeElement> IS_TRAIT = Rule.on(TypeElement.class)
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.and(is(INTERFACE))
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.and(isNamedTesting(TraitProcessor::isValidName, "must end with 'ble' or start with 'Has'"))
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.and(it(TraitProcessor::hasAtLeastOneMethod, "'%s' must have at least one method"));
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}

‎java-design-processor/src/main/java/internal/nbbrd/design/proc/Elements2.java‎

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@@ -3,13 +3,18 @@
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import javax.lang.model.element.*;
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import javax.lang.model.util.ElementFilter;
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import java.lang.annotation.Annotation;
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import java.util.function.Predicate;
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import java.util.stream.Stream;
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@lombok.experimental.UtilityClass
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public class Elements2 {
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public static boolean isNamed(Element e, String name) {
12-
return e.getSimpleName().toString().equals(name);
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return isNamedTesting(e, name::equals);
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}
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public static boolean isNamedTesting(Element e, Predicate<? super String> namePredicate) {
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return namePredicate.test(e.getSimpleName().toString());
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}
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public static boolean is(Element e, Modifier modifier) {

‎java-design-processor/src/main/java/internal/nbbrd/design/proc/ExecutableRules.java‎

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public class ExecutableRules {
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public static Rule<ExecutableElement> hasNoParameter() {
19-
return of(m -> m.getParameters().isEmpty(), "'%s' must not have parameters");
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return Rule.it(m -> m.getParameters().isEmpty(), "'%s' must not have parameters");
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}
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public static Rule<ExecutableElement> hasParametersThat(Rule<? super VariableElement>... rules) {

‎java-design-processor/src/main/java/internal/nbbrd/design/proc/Rule.java‎

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@@ -70,7 +70,7 @@ static <T extends Element> Rule<T> on(Class<T> ignore) {
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return (env, e) -> NO_ERROR;
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}
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static <T extends Element> Rule<T> of(Predicate<? super T> condition, String formattedMessage) {
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static <T extends Element> Rule<T> it(Predicate<? super T> condition, String formattedMessage) {
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return (env, e) -> !condition.test(e) ? String.format(Locale.ROOT, formattedMessage, e) : NO_ERROR;
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}
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}
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8585
static <T extends Element> Rule<T> is(Modifier modifier) {
86-
return of(e -> Elements2.is(e, modifier), "'%s' must be " + modifier);
86+
return it(e -> Elements2.is(e, modifier), "'%s' must be " + modifier);
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}
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8989
static <T extends Element> Rule<T> isNot(Modifier modifier) {
90-
return of(e -> !Elements2.is(e, modifier), "'%s' must not be " + modifier);
90+
return it(e -> !Elements2.is(e, modifier), "'%s' must not be " + modifier);
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}
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9393
static <T extends Element> Rule<T> is(ElementKind kind) {
94-
return of(e -> Elements2.is(e, kind), "'%s' must be " + kind);
94+
return it(e -> Elements2.is(e, kind), "'%s' must be " + kind);
9595
}
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9797
static <T extends Element> Rule<T> isNamed(String name) {
98-
return of(e -> Elements2.isNamed(e, name), "'%s' must be named " + name);
98+
return it(e -> Elements2.isNamed(e, name), "'%s' must be named " + name);
99+
}
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101+
static <T extends Element> Rule<T> isNamedTesting(Predicate<? super String> namePredicate, String predicateDescription) {
102+
return it(e -> Elements2.isNamedTesting(e, namePredicate), "'%s' must " + predicateDescription);
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}
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101105
static <T extends Element> Rule<T> is(Element expected) {

‎java-design-processor/src/main/java/internal/nbbrd/design/proc/TypeRules.java‎

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import static internal.nbbrd.design.proc.Elements2.constructorsIn;
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import static internal.nbbrd.design.proc.Elements2.is;
7-
import static internal.nbbrd.design.proc.Rule.of;
87
import static javax.lang.model.element.Modifier.PUBLIC;
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@lombok.experimental.UtilityClass
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public class TypeRules {
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1312
public static Rule<TypeElement> hasNoInterface() {
14-
return of(type -> type.getInterfaces().isEmpty(), "'%s' must not implement interfaces");
13+
return Rule.it(type -> type.getInterfaces().isEmpty(), "'%s' must not implement interfaces");
1514
}
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1716
public static Rule<TypeElement> hasNoPublicConstructor() {
18-
return of(type -> constructorsIn(type).noneMatch(method -> is(method, PUBLIC)), "'%s' cannot have public constructors");
17+
return Rule.it(type -> constructorsIn(type).noneMatch(method -> is(method, PUBLIC)), "'%s' cannot have public constructors");
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}
2019
}

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