Apache Freemarker

package org.apache.plc4x.language.java;

import com.google.googlejavaformat.java.Formatter;
import com.google.googlejavaformat.java.FormatterException;
import freemarker.template.Configuration;
import freemarker.template.Template;
import org.apache.commons.io.FileUtils;
import org.apache.plc4x.plugins.codegenerator.protocol.freemarker.FreemarkerLanguageOutput;
import org.apache.plc4x.plugins.codegenerator.protocol.freemarker.FreemarkerLanguageTemplateHelper;
import org.apache.plc4x.plugins.codegenerator.types.definitions.TypeDefinition;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;

import java.io.File;
import java.io.IOException;
import java.nio.charset.StandardCharsets;
import java.util.*;

public class JavaLanguageOutput extends FreemarkerLanguageOutput {

    private static final Logger LOGGER = LoggerFactory.getLogger(JavaLanguageOutput.class);

    private final Formatter formatter = new Formatter();

    @Override
    public String getName() {
        return "Java";
    }

    @Override
    public Set<String> supportedOptions() {
        return Collections.singleton("package");
    }

    @Override
    public List<String> supportedOutputFlavors() {
        return Arrays.asList("read-write", "read-only", "passive");
    }

    @Override
    protected List<Template> getSpecTemplates(Configuration freemarkerConfiguration) {
        return Collections.emptyList();
    }

    @Override
    protected List<Template> getComplexTypeTemplates(Configuration freemarkerConfiguration) throws IOException {
        return Arrays.asList(
            freemarkerConfiguration.getTemplate("templates/java/pojo-template.java.ftlh"),
            freemarkerConfiguration.getTemplate("templates/java/io-template.java.ftlh"));
    }

    @Override
    protected List<Template> getEnumTypeTemplates(Configuration freemarkerConfiguration) throws IOException {
        return Collections.singletonList(
            freemarkerConfiguration.getTemplate("templates/java/enum-template.java.ftlh"));
    }

    @Override
    protected List<Template> getDataIoTemplates(Configuration freemarkerConfiguration) throws IOException {
        return Collections.singletonList(
            freemarkerConfiguration.getTemplate("templates/java/data-io-template.java.ftlh"));
    }

    @Override
    protected FreemarkerLanguageTemplateHelper getHelper(TypeDefinition thisType, String protocolName, String flavorName, Map<String, TypeDefinition> types,
                                                         Map<String, String> options) {
        return new JavaLanguageTemplateHelper(thisType, protocolName, flavorName, types, options);
    }

    @Override
    protected void postProcessTemplateOutput(File outputFile) {
        try {
            FileUtils.writeStringToFile(
                outputFile,
                formatter.formatSourceAndFixImports(
                    FileUtils.readFileToString(outputFile, StandardCharsets.UTF_8)
                ),
                StandardCharsets.UTF_8
            );
        } catch (IOException | FormatterException e) {
            LOGGER.error("Error formatting {}", outputFile, e);
        }
    }
}

${helper.packageName(protocolName, languageName, outputFlavor)?replace(".", "/")}/${type.name}.java
/*
 * Licensed to the Apache Software Foundation (ASF) under one
 * or more contributor license agreements.  See the NOTICE file
 * distributed with this work for additional information
 * regarding copyright ownership.  The ASF licenses this file
 * to you 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 ${helper.packageName(protocolName, languageName, outputFlavor)};

... imports ...

// Code generated by code-generation. DO NOT EDIT.

public<#if type.isDiscriminatedParentTypeDefinition()> abstract</#if> class ${type.name}<#if type.parentType??> extends ${type.parentType.name}</#if> implements Message {

    ... SNIP ...

}