Question

最近我开始研究Java Servlet异步功能。我编写了如下所示的示例代码来检查aysnc功能。我在单核处理器上运行它。我从jsp提交了100个请求（图像请求）。我在代码中添加了“Request Submmited :::”SOP。它显示前0到6个请求的SOP，然后在一段时间后显示6到11的SOP ....为什么它不显示所有100个请求的SOP。

package com.test;
import java.io.FileInputStream;
import java.io.IOException;

import javax.servlet.AsyncContext;
import javax.servlet.ServletException;
import javax.servlet.annotation.WebServlet;
import javax.servlet.http.HttpServlet;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;

@WebServlet(urlPatterns={"/Test"}, asyncSupported = true)
public class Test extends HttpServlet {
private static final long serialVersionUID = 1L;

public Test() {
    super();
}

int counter = 0;
@Override
protected void doGet(final HttpServletRequest request,
        final HttpServletResponse response) throws ServletException,
        IOException {
    System.out.println("Request Submmited:::" + counter++);
    final AsyncContext ctx = request.startAsync();
    ctx.start(new Runnable() {
        public void run() {
            try {
                String count = request.getParameter("test");
                try {
                    Thread.sleep(10000);
                } catch (InterruptedException e) {
                    // TODO Auto-generated catch block
                    e.printStackTrace();
                }
                FileInputStream fin = new FileInputStream(
                        "D:/TESTImages/8_0_0_NUCLEI" + count + ".jpg");
                byte[] data = new byte[fin.available()];
                fin.read(data);
                response.getWriter().print(new String(data));
                response.flushBuffer();

            } catch (Exception e) {
                e.printStackTrace();
            }
            ctx.complete();
        }
    });
}

protected void doPost(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {
    // TODO Auto-generated method stub
}

}

Answer 1

对于在servlet容器中处理异步请求的池，似乎默认线程池大小为 5 。尝试提供init params，如下所示：

@javax.servlet.annotation.WebServlet(urlPatterns={"/Test"}, asyncSupported = true, 
initParams = { @WebInitParam(name = "threadpoolsize", value = "100") })

Java Servlet异步支持

1 个答案: