Java 通过一个线程获取作业，但通过多个线程并行执行作业

我正在从一家DB公司找工作。我希望从数据库获取记录是单线程的。一旦我有了所有的作业，我想让它们以并行的线程数执行。

正如您所说，您正在使用Spring，我建议您查找

然后，您可以让查询DB的线程将作业（包装为

Callable

或

Runnable

）提交给

ThreadPoolTaskExecutor

首先从数据库中获取要处理的记录

我正在将记录与客户分组

我正在将每个客户的处理传递到线程池

.....
@Autowired
ThreadPoolTaskExecutor taskExecutor;

@Autowired
private ApplicationContext applicationContext;

@Transactional
public void processPendingPayments() {
    logger.debug("ProcessPendingPayments.processPendingPayments begins");
    logger.info("startTime::" + System.currentTimeMillis());
    List<PaymentRequestEntity> recordsPendingForPayment = getRecordsPendingForPayment();

    // Group Requests with Customers
    Map<String, List<PaymentRequestEntity>> customerPaymentRequestsMap = getPendingRecordsGroupedByCustomer(
            recordsPendingForPayment);

    // process Payment requests for customers
    for (String customerId : customerPaymentRequestsMap.keySet()) {

        CustomerPaymentRequestProcessor customerPaymentRequestProcessor = (CustomerPaymentRequestProcessor) applicationContext
                .getBean("customerPaymentRequestProcessor");
        customerPaymentRequestProcessor.setStrCustomerId(customerId);
        customerPaymentRequestProcessor.setCustomerPaymentRequestsMap(customerPaymentRequestsMap);
        taskExecutor.execute(customerPaymentRequestProcessor);

    }
    logger.info("endTime::" + System.currentTimeMillis());
    logger.debug("ProcessPendingPayments.processPendingPayments ends");
}
........

。。。。。
@自动连线
线程池任务执行器任务执行器；
@自动连线
私有应用程序上下文应用程序上下文；
@交易的
public void processPendingPayments（）{
调试（“ProcessPendingPayments.ProcessPendingPayments开始”）；
logger.info（“startTime:：”+System.currentTimeMillis（））；
List recordsPendingForPayment=getRecordsPendingForPayment（）；
//与客户分组请求
映射customerPaymentRequestsMap=getPendingRecordsGroupedByCustomer(
付款记录）；
//处理客户的付款请求
for（字符串customerId:customerPaymentRequestsMap.keySet（））{
CustomerPaymentRequestProcessor CustomerPaymentRequestProcessor=（CustomerPaymentRequestProcessor）应用上下文
.getBean（“customerPaymentRequestProcessor”）；
customerPaymentRequestProcessor.setStrCustomerId（customerId）；
customerPaymentRequestProcessor.setCustomerPaymentRequestsMap（customerPaymentRequestsMap）；
taskExecutor.execute（customerPaymentRequestProcessor）；
}
logger.info（“endTime:：”+System.currentTimeMillis（））；
调试（“ProcessPendingPayments.ProcessPendingPayments结束”）；
}
........

下面是处理每个客户记录的Runnable类的代码

@Component
@Scope("prototype")
public class CustomerPaymentRequestProcessor implements Runnable {

    private static final Logger logger = LoggerFactory.getLogger(CustomerPaymentRequestProcessor.class);

    private String strCustomerId;

    private Map<String, List<PaymentRequestEntity>> customerPaymentRequestsMap;

    private final String REQUEST_TYPE_BALANCE = "Balance";

    @Autowired
    private BalanceServiceImpl balanceServiceImpl;

    @Autowired
    PendingPaymentsSequenceProcessor pendingPaymentsSequenceProcessor;

    @Autowired
    CustomerAuditServiceImpl customerAuditServiceImpl;

    public CustomerPaymentRequestProcessor() {

    }

    public CustomerPaymentRequestProcessor(String strCustomerId,
            Map<String, List<PaymentRequestEntity>> customerPaymentRequestsMap) {
        super();
        this.strCustomerId = strCustomerId;
        this.customerPaymentRequestsMap = customerPaymentRequestsMap;
    }

    @Override
    public void run() {
        logger.debug("CustomerPaymentRequestProcessor.run starts");
        List<PaymentRequestEntity> paymentRequests = getCustomerPaymentRequestsMap().get(getStrCustomerId());
        for (PaymentRequestEntity paymentRequest : paymentRequests) {

            CustomerBalanceResponse customerBalanceResponse = processPaymentRequest(paymentRequest);
            if (!customerBalanceResponse.isCustomerHasBalance()
                    && REQUEST_TYPE_BALANCE.equals(paymentRequest.getRequestType())) {
                break;
            }

        }
        logger.debug("CustomerPaymentRequestProcessor.run ends");
    }
    ....
    ....
    }

@组件
@范围（“原型”）
公共类CustomerPaymentRequestProcessor实现Runnable{
私有静态最终记录器Logger=LoggerFactory.getLogger（CustomerPaymentRequestProcessor.class）；
私有字符串strCustomerId；
私有地图customerPaymentRequestsMap；
私有最终字符串请求\u类型\u BALANCE=“BALANCE”；
@自动连线
私人余额服务impl余额服务impl；
@自动连线
PendingPaymentsSequenceProcessor PendingPaymentsSequenceProcessor；
@自动连线
CustomerAuditServiceImpl CustomerAuditServiceImpl；
公共CustomerPaymentRequestProcessor（）{
}
公共CustomerPaymentRequestProcessor（字符串strustomeId，
映射customerPaymentRequestsMap）{
超级（）；
this.strustomerid=strustomerid；
this.customerPaymentRequestsMap=customerPaymentRequestsMap；
}
@凌驾
公开募捐{
debug（“CustomerPaymentRequestProcessor.run启动”）；
List paymentRequests=getCustomerPaymentRequestsMap（）.get（GetStrcustomeId（））；
for（PaymentRequestEntity paymentRequest:paymentRequests）{
CustomerBalanceResponse CustomerBalanceResponse=processPaymentRequest（paymentRequest）；
如果（！customerBalanceResponse.isCustomerHasBalance（））
&&请求\类型\余额.equals（paymentRequest.getRequestType（））{
打破
}
}
debug（“CustomerPaymentRequestProcessor.run结束”）；
}
....
....
}

---

你的问题到底是什么？到目前为止，您尝试了什么？我正在使用Spring调度程序来实现这一点。但是所有这些我都是用一个线程来完成的。但是现在我打算让它成为多线程的。很抱歉，你的问题并没有真正说明你的问题。但为了有所帮助，请尝试设置一个由查询数据库的线程填充的

BlockingQueue

，并从队列中轮询线程池，直到队列为空。@JeremyGrand:谢谢我的尝试。但有没有比使用阻塞队列更好的方法呢。