org.openrewrite.java.ImplementInterface Maven / Gradle / Ivy

/*
 * Copyright 2020 the original author or 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
 * 

 * https://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.openrewrite.java;

import io.micrometer.core.instrument.Tag;
import io.micrometer.core.instrument.Tags;
import org.openrewrite.java.tree.J;
import org.openrewrite.java.tree.JavaType;
import org.openrewrite.java.tree.TypeTree;

import java.util.ArrayList;
import java.util.List;

import static java.util.Collections.singletonList;
import static org.openrewrite.Formatting.format;
import static org.openrewrite.Tree.randomId;

public class ImplementInterface extends JavaRefactorVisitor {
    private final J.ClassDecl scope;
    private final String interfaze;
    private final JavaType.Class interfaceType;

    public ImplementInterface(J.ClassDecl scope, String interfaze) {
        this.scope = scope;
        this.interfaze = interfaze;
        this.interfaceType = JavaType.Class.build(interfaze);
    }

    @Override
    public Iterable getTags() {
        return Tags.of("from", interfaze);
    }

    @Override
    public J visitClassDecl(J.ClassDecl classDecl) {
        J.ClassDecl c = refactor(classDecl, super::visitClassDecl);
        if (scope.isScope(classDecl) && (classDecl.getImplements() == null ||
                classDecl.getImplements().getFrom().stream().noneMatch(f -> interfaceType.equals(f.getType())))) {
            maybeAddImport(interfaze);

            J.Ident lifeCycle = J.Ident.buildClassName(interfaze).withFormatting(format(" "));

            if (c.getImplements() == null) {
                c = c.withImplements(new J.ClassDecl.Implements(randomId(),
                        singletonList(lifeCycle),
                        format(" ")));
            }
            else {
                List implementings = new ArrayList<>(c.getImplements().getFrom());
                implementings.add(0, lifeCycle);
                c = c.withImplements(c.getImplements().withFrom(implementings));
            }
        }

        return c;
    }
}