PluginManager.java

package org.heater.core.plugin;

import com.google.inject.AbstractModule;
import com.google.inject.multibindings.Multibinder;
import org.heater.api.HeaterActivator;

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

public class PluginManager {
    private final List<HeaterActivator> instances;
    private Module cache;

    public PluginManager() {
        this.instances = new ArrayList<>();
    }

    public PluginManager initialize() {
        //TODO: insert modules main class
        if (cache == null) {
            cache = buildModule();
        }
        return this;
    }

    private Module buildModule() {
        return new AbstractModule() {
            @Override
            protected void configure() {
                Multibinder<HeaterActivator> binder = Multibinder.newSetBinder(binder(), HeaterActivator.class);
                for(HeaterActivator instance: instances) {
                    binder.addBinding().toInstance(instance);
                    install(instance.pluginModule());
                }
            }
        };
    }

    public Module getModule() {
        if (cache == null) {
            throw new IllegalStateException("please initialize first");
        }
        return this.module;
    }
}