标签:根据 主机 java.net url tostring ack i++ line tac
有时需要测试一下某个功能的并发性能,又不要想借助于其他工具,索性就自己的开发语言,来一个并发请求就最方便了。
java中模拟并发请求,自然是很方便的,只要多开几个线程,发起请求就好了。但是,这种请求,一般会存在线后顺序了。怎么样才能做到真正的同时并发呢?是本文想说的点,java中提供了闭锁 CountDownLatch, 刚好就用来做这种事就最合适了。
只需要: 1. 开启n个线程,加一个闭锁,开启所有线程; 2. 待所有线程都准备好后,按下开启按钮,就可以真正的发起并发请求了。
package com.yougewe.test; import java.io.BufferedReader; import java.io.IOException; import java.io.InputStream; import java.io.InputStreamReader; import java.io.OutputStream; import java.net.HttpURLConnection; import java.net.MalformedURLException; import java.net.URL; import java.util.concurrent.CountDownLatch; /** * Created by weiyong on 2018/10/5. */ public class LatchTest { public static void main(String[] args) throws InterruptedException { Runnable taskTemp = new Runnable() { private int iCounter; @Override public void run() { for(int i = 0; i < 10; i++) { // 发起请求 // HttpClientOp.doGet("https://www.baidu.com/"); iCounter++; System.out.println(System.nanoTime() + " [" + Thread.currentThread().getName() + "] iCounter = " + iCounter); try { Thread.sleep(100); } catch (InterruptedException e) { e.printStackTrace(); } } } }; LatchTest latchTest = new LatchTest(); latchTest.startTaskAllInOnce(5, taskTemp); } public long startTaskAllInOnce(int threadNums, final Runnable task) throws InterruptedException { final CountDownLatch startGate = new CountDownLatch(1); final CountDownLatch endGate = new CountDownLatch(threadNums); for(int i = 0; i < threadNums; i++) { Thread t = new Thread() { public void run() { try { // 使线程在此等待,当开始门打开时,一起涌入门中 startGate.await(); try { task.run(); } finally { // 将结束门减1,减到0时,就可以开启结束门了 endGate.countDown(); } } catch (InterruptedException ie) { ie.printStackTrace(); } } }; t.start(); } long startTime = System.nanoTime(); System.out.println(startTime + " [" + Thread.currentThread() + "] All thread is ready, concurrent going..."); // 因开启门只需一个开关,所以立马就开启开始门 startGate.countDown(); // 等等结束门开启 endGate.await(); long endTime = System.nanoTime(); System.out.println(endTime + " [" + Thread.currentThread() + "] All thread is completed."); return endTime - startTime; } }
httpClientOp 工具类,可以使用 成熟的工具包,也可以自己写一个简要的访问方法,参考如下:
class HttpClientOp { public static String doGet(String httpurl) { HttpURLConnection connection = null; InputStream is = null; BufferedReader br = null; String result = null;// 返回结果字符串 try { // 创建远程url连接对象 URL url = new URL(httpurl); // 通过远程url连接对象打开一个连接,强转成httpURLConnection类 connection = (HttpURLConnection) url.openConnection(); // 设置连接方式:get connection.setRequestMethod("GET"); // 设置连接主机服务器的超时时间:15000毫秒 connection.setConnectTimeout(15000); // 设置读取远程返回的数据时间:60000毫秒 connection.setReadTimeout(60000); // 发送请求 connection.connect(); // 通过connection连接,获取输入流 if (connection.getResponseCode() == 200) { is = connection.getInputStream(); // 封装输入流is,并指定字符集 br = new BufferedReader(new InputStreamReader(is, "UTF-8")); // 存放数据 StringBuffer sbf = new StringBuffer(); String temp = null; while ((temp = br.readLine()) != null) { sbf.append(temp); sbf.append("\r\n"); } result = sbf.toString(); } } catch (MalformedURLException e) { e.printStackTrace(); } catch (IOException e) { e.printStackTrace(); } finally { // 关闭资源 if (null != br) { try { br.close(); } catch (IOException e) { e.printStackTrace(); } } if (null != is) { try { is.close(); } catch (IOException e) { e.printStackTrace(); } } connection.disconnect();// 关闭远程连接 } return result; } public static String doPost(String httpUrl, String param) { HttpURLConnection connection = null; InputStream is = null; OutputStream os = null; BufferedReader br = null; String result = null; try { URL url = new URL(httpUrl); // 通过远程url连接对象打开连接 connection = (HttpURLConnection) url.openConnection(); // 设置连接请求方式 connection.setRequestMethod("POST"); // 设置连接主机服务器超时时间:15000毫秒 connection.setConnectTimeout(15000); // 设置读取主机服务器返回数据超时时间:60000毫秒 connection.setReadTimeout(60000); // 默认值为:false,当向远程服务器传送数据/写数据时,需要设置为true connection.setDoOutput(true); // 默认值为:true,当前向远程服务读取数据时,设置为true,该参数可有可无 connection.setDoInput(true); // 设置传入参数的格式:请求参数应该是 name1=value1&name2=value2 的形式。 connection.setRequestProperty("Content-Type", "application/x-www-form-urlencoded"); // 设置鉴权信息:Authorization: Bearer da3efcbf-0845-4fe3-8aba-ee040be542c0 connection.setRequestProperty("Authorization", "Bearer da3efcbf-0845-4fe3-8aba-ee040be542c0"); // 通过连接对象获取一个输出流 os = connection.getOutputStream(); // 通过输出流对象将参数写出去/传输出去,它是通过字节数组写出的 os.write(param.getBytes()); // 通过连接对象获取一个输入流,向远程读取 if (connection.getResponseCode() == 200) { is = connection.getInputStream(); // 对输入流对象进行包装:charset根据工作项目组的要求来设置 br = new BufferedReader(new InputStreamReader(is, "UTF-8")); StringBuffer sbf = new StringBuffer(); String temp = null; // 循环遍历一行一行读取数据 while ((temp = br.readLine()) != null) { sbf.append(temp); sbf.append("\r\n"); } result = sbf.toString(); } } catch (MalformedURLException e) { e.printStackTrace(); } catch (IOException e) { e.printStackTrace(); } finally { // 关闭资源 if (null != br) { try { br.close(); } catch (IOException e) { e.printStackTrace(); } } if (null != os) { try { os.close(); } catch (IOException e) { e.printStackTrace(); } } if (null != is) { try { is.close(); } catch (IOException e) { e.printStackTrace(); } } // 断开与远程地址url的连接 connection.disconnect(); } return result; } }
如上,就可以发起真正的并发请求了。
标签:根据 主机 java.net url tostring ack i++ line tac
原文地址:https://www.cnblogs.com/yougewe/p/9745198.html