GenericConfig.java

package test;

import java.io.IOException;
import java.nio.file.Files;
import java.nio.file.Path;
import java.nio.file.Paths;
import java.util.ArrayList;
import java.util.List;

public class GenericConfig implements Config {
    private String confFile;
    private final List<ParallelAgent> agents = new ArrayList<>();

    public void setConfFile(String confFile) {
        this.confFile = confFile;
    }

    @Override
    public void create() {
        if (confFile == null) {
            return;
        }
        List<String> lines;
        try {
            lines = Files.readAllLines(Paths.get(confFile));
        } catch (IOException e) {
            return;
        }
        if (lines.size() % 3 != 0) {
            return;
        }
        for (int i = 0; i < lines.size(); i += 3) {
            String className = lines.get(i).trim();
            String[] subs = splitTopics(lines.get(i + 1));
            String[] pubs = splitTopics(lines.get(i + 2));
            Agent agent = instantiateAgent(className, subs, pubs);
            if (agent == null) {
                continue;
            }
            ParallelAgent pa = new ParallelAgent(agent, 10);
            replaceAgentInTopics(agent, pa);
            agents.add(pa);
        }
    }

    private String[] splitTopics(String line) {
        if (line == null || line.trim().isEmpty()) {
            return new String[0];
        }
        String[] raw = line.split(",");
        for (int i = 0; i < raw.length; i++) {
            raw[i] = raw[i].trim();
        }
        return raw;
    }

    private Agent instantiateAgent(String className, String[] subs, String[] pubs) {
        try {
            Class<?> cls = Class.forName(className);
            return (Agent) cls.getConstructor(String[].class, String[].class)
                    .newInstance((Object) subs, (Object) pubs);
        } catch (Exception e) {
            return null;
        }
    }

    private void replaceAgentInTopics(Agent original, Agent replacement) {
        for (Topic topic : TopicManagerSingleton.get().getTopics()) {
            replaceInList(topic.getSubscribers(), original, replacement);
            replaceInList(topic.getPublishers(), original, replacement);
        }
    }

    private void replaceInList(List<Agent> list, Agent original, Agent replacement) {
        for (int i = 0; i < list.size(); i++) {
            if (list.get(i) == original) {
                list.set(i, replacement);
            }
        }
    }

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

    @Override
    public int getVersion() {
        return 1;
    }

    @Override
    public void close() {
        for (ParallelAgent agent : agents) {
            agent.close();
        }
        agents.clear();
    }
}