design/designer-base/src/main/java/com/fr/design/mainframe/theme/AsyncThemeFetcher.java

package com.fr.design.mainframe.theme;

import com.fr.base.theme.TemplateTheme;
import com.fr.base.theme.TemplateThemeConfig;
import com.fr.concurrent.NamedThreadFactory;
import com.fr.module.ModuleContext;

import javax.swing.SwingUtilities;
import java.util.concurrent.ExecutorService;

/**
 * @author Starryi
 * @version 1.0
 * Created by Starryi on 2021/8/24
 */
public class AsyncThemeFetcher<T extends TemplateTheme> {

    private final ExecutorService executorService;
    private final TemplateThemeConfig<T> config;

    public AsyncThemeFetcher(int threads, TemplateThemeConfig<T> config) {
        this.executorService = ModuleContext.getExecutor().newFixedThreadPool(
                threads,
                new NamedThreadFactory(this.getClass().getName())
        );
        this.config = config;
    }

    public void shutdown() {
        executorService.shutdown();
    }

    public boolean isShutdown() {
        return executorService.isShutdown();
    }

    public void submit(String themeName, AsyncThemeFetchCallback<T> callback) {
        if (callback != null) {
            callback.beforeCachedFetch();
        }
        executorService.submit(new Runnable() {
            @Override
            public void run() {
                if (executorService.isShutdown()) {
                    return;
                }
                T theme = config.cachedFetch(themeName);
                if (executorService.isShutdown()) {
                    return;
                }
                if (callback != null) {
                    // 后续任务不要在工作线程中执行，从而确保只在EDT线程操作UI
                    SwingUtilities.invokeLater(new Runnable() {
                        @Override
                        public void run() {
                            callback.afterCachedFetch(theme);
                        }
                    });
                }
            }
        });
    }

    public interface AsyncThemeFetchCallback<T extends TemplateTheme> {
        void beforeCachedFetch();
        void afterCachedFetch(T theme);
    }

    public static class AsyncThemeFetchCallbackAdapter<T extends TemplateTheme> implements AsyncThemeFetchCallback<T> {

        @Override
        public void beforeCachedFetch() {

        }

        @Override
        public void afterCachedFetch(T theme) {

        }
    }
}