ClasspathBackend.java

package me.rschatz;

import com.glassdoor.planout4j.config.Planout4jConfigBackend;
import com.typesafe.config.Config;
import org.apache.commons.io.Charsets;
import org.apache.commons.io.IOUtils;

import java.io.IOException;
import java.util.ArrayList;
import java.util.HashMap;
import java.util.List;
import java.util.Map;

import static com.google.common.io.Files.getNameWithoutExtension;

public class ClasspathBackend implements Planout4jConfigBackend {

    /**
     * {@link ClasspathBackend} does not need to be configured.
     * @param config any {@link Config}
     */
    @Override
    public void configure(Config config) { }

    /**
     * Loads and returns a mapping of namespace names to json based on files in the {@code planout} resource directory.
     * @return Map
     */
    @Override
    public Map<String, String> loadAll() {
        final Map<String, String> name2Content = new HashMap<>();

        for (String jsonFile : getJsonResourceFiles()) {
            final String namespace = getNameWithoutExtension(jsonFile);
            final String json = readJson("planout/" + jsonFile);
            name2Content.put(namespace, json);
        }
        return name2Content;
    }

    private String readJson(final String jsonFileName) {
        try {
            return IOUtils.toString(ClasspathBackend.class.getClassLoader().getResourceAsStream(jsonFileName));
        } catch (IOException e) {
            throw new IllegalStateException(e);
        }
    }

    private Iterable<String> getJsonResourceFiles() {
        final List<String> files = new ArrayList<>();

        try {
            for (String fileName : IOUtils.readLines(
                    ClasspathBackend.class.getClassLoader().getResourceAsStream("planout/"), Charsets.UTF_8)) {
                if (fileName.endsWith(".json")) {
                    files.add(fileName);
                }
            }
        } catch (IOException e) {
            throw new IllegalStateException(e);
        }
        return files;
    }

    /**
     * This backend does not persist anything.
     * @param namespace2Content - ??
     */
    @Override
    public void persist(Map<String, String> namespace2Content) {
        throw new UnsupportedOperationException("Not implemented!");
    }

    @Override
    public String persistenceLayer() {
        return "CLASSPATH";
    }

    @Override
    public String persistenceDestination() {
        return this.getClass().getName();
    }

    // for test purposes only
    public static void main(String[] args) {
        final Planout4jConfigBackend backend = new ClasspathBackend();
        final Map<String, String> namespaces = backend.loadAll();
        System.out.println(namespaces);
    }
}