Java实时数据处理之三-池化技术（线程池 & 对象池）

线程池使用步骤：

1、自定义线程池

private ThreadPoolExecutor executor;

    /**
     * 初始化线程池
     */
    @PostConstruct
    private void init(){
        int processors = Runtime.getRuntime().availableProcessors();
        int corePoolSize = processors * 2;
        LinkedBlockingQueue queue = new LinkedBlockingQueue();
        // 自定义线程池
        executor = new ThreadPoolExecutor(corePoolSize, corePoolSize * 2,
                60, TimeUnit.SECONDS, queue, new ThreadPoolDemoFactory("demo"));
        log.info("CorePoolSize: {}", executor.getCorePoolSize());
        log.info("MaximumPoolSize: {}", executor.getMaximumPoolSize());

    }

2、给多线程构造任务

   /**
     * 使用多线程，批量插入数据到MySql
     */
    @RequestMapping("/")
    private void batchSave2MySql() throws SQLException {
        // 创建一个存储CompletableFuture的数组，存储异步调用的对象
        List<CompletableFuture<?>> futures = new ArrayList<>(1000000);
        Connection conn = MySqlUtils.getConn();
        Device device1 = new Device();
        Device device2 = new Device();
        device1.setName("device1");
        device1.setTypeId(1);
        device2.setName("device2");
        device2.setTypeId(2);
        List<Device> list = Lists.newArrayList();
        list.add(device1);
        list.add(device2);
        // 给多线程构造任务
        for(Device device : list){
            PreparedStatement stmts = conn.prepareStatement
                    ("insert into device values(?,?,?)");
            stmts.setString(1, UUID.randomUUID().toString());
            stmts.setString(2, device.getName());
            stmts.setInt(3, device.getTypeId());
            // 多线程执行后的返回结果在哪？？
            CompletableFuture future = CompletableFuture.supplyAsync(() -> {
                try {
                    return stmts.execute();
                } catch (SQLException e) {
                    throw new RuntimeException(e);
                }
            }, executor);
            futures.add(future);
        }

    }

3、多线程执行（自动）

git：https://gitee.com/caesarthegreat/thread-pool-demo.git