RuleProcessorValidator.java

/**
 * Powerunit - A JDK1.8 test framework
 * Copyright (C) 2014 Mathieu Boretti.
 *
 * This file is part of Powerunit
 *
 * Powerunit is free software: you can redistribute it and/or modify
 * it under the terms of the GNU General Public License as published by
 * the Free Software Foundation, either version 3 of the License, or
 * (at your option) any later version.
 *
 * Powerunit is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 * GNU General Public License for more details.
 *
 * You should have received a copy of the GNU General Public License
 * along with Powerunit. If not, see <http://www.gnu.org/licenses/>.
 */
package ch.powerunit.impl.validator;

import java.util.HashSet;
import java.util.Set;

import javax.annotation.processing.ProcessingEnvironment;
import javax.annotation.processing.RoundEnvironment;
import javax.lang.model.element.Element;
import javax.lang.model.element.ElementKind;
import javax.lang.model.element.Modifier;
import javax.lang.model.element.Name;
import javax.lang.model.element.TypeElement;
import javax.lang.model.type.DeclaredType;
import javax.lang.model.type.TypeKind;
import javax.lang.model.type.TypeMirror;

import ch.powerunit.Rule;

public interface RuleProcessorValidator extends ProcessValidator {
    default void ruleAnnotationValidation(ProcessingEnvironment processingEnv,
            RoundEnvironment roundEnv) {
        Set<Name> exists = new HashSet<>();
        Set<? extends Element> elements = roundEnv
                .getElementsAnnotatedWith(Rule.class);
        TypeElement testRule = processingEnv.getElementUtils().getTypeElement(
                "ch.powerunit.TestRule");
        for (Element element : elements) {
            if (element.getKind() != ElementKind.FIELD) {
                error("@Rule must prefix a field -- " + element
                        + " is not a field");
                continue;
            }
            Element parent = element.getEnclosingElement();
            if (exists.contains(parent.getSimpleName())) {
                warn("Class "
                        + elementAsString(parent)
                        + "\n\t contains more than one @Rule field\n\tOnly one @Run method is field for a test class");
            }
            exists.add(parent.getSimpleName());
            if (element.getModifiers().contains(Modifier.STATIC)) {
                warn("Field "
                        + elementAsString(element)
                        + "\n\tis prefixed with @Rule and is static\n\tA rule field can't be static");
            }
            if (!element.getModifiers().contains(Modifier.PUBLIC)) {
                warn("Field "
                        + elementAsString(element)
                        + "\n\tis prefixed with @Rule and is not public\n\tA rule field must be public");
            }
            if (!element.getModifiers().contains(Modifier.FINAL)) {
                warn("Field "
                        + elementAsString(element)
                        + "\n\tis prefixed with @Rule and is not fianl\n\tA rule field must be final");
            }
            TypeMirror rt = element.asType();
            if (rt.getKind() != TypeKind.DECLARED) {
                warn("Field " + elementAsString(element)
                        + "\n\tis prefixed with @Rule and is " + rt
                        + "\n\tA rule field must be " + testRule);
            } else {
                DeclaredType dt = (DeclaredType) rt;
                if (!processingEnv.getTypeUtils().isSubtype(
                        dt.asElement().asType(), testRule.asType())) {
                    warn("Field " + elementAsString(element)
                            + "\n\tis prefixed with @Rule and is "
                            + dt.asElement().asType()
                            + "\n\tA rule field must be " + testRule);
                }
            }

        }
    }
}