一个应用，如果并发操作过多，就会导致卡顿，用户体验很不好。
我们可以通过线程池的方式，从某种角度来控制并发数，但是这就要求我们写代码的时候严格规范，能发现的耗时操作都放到线程池。
下面是我自己写的一个工具类，也可以直接将里面代码扔到application。
不多哔哔，上代码：
public class AppThreadPool {
/**
* 单例,可以将该类放到Application中,实现整个APP控制线程的目的
*/
private static AppThreadPool pool;
/**
* 线程池
*/
ExecutorService tPool;
/**
* 连接超时时间
*/
private static final int connectionTime = 5000;
/**
* read超时时间
*/
private static final int readTime = 10000;
/**
* 单例获取,否则线程池失去目的,不如直接new Thread来得爽
* @return
*/
public static AppThreadPool getPool() {
if (pool == null) {
pool = new AppThreadPool();
}
return pool;
}
public AppThreadPool() {
// TODO Auto-generated constructor stub
int count = getCPUcount();
tPool = Executors.newFixedThreadPool(count);
}
/**
* 获取设备CPU核心数,用来设置线程池大小
* 小于8则固定返回5,大于等于8则返回核心数的四分之三
* @return
*/
private int getCPUcount() {
int xxx = Runtime.getRuntime().availableProcessors();
if (xxx < 8) {
return 5;
} else {
return xxx / 3 * 4;
}
}
/**
* 请求数据
* @param httpurl 请求地址
* @param headers 请求头,某些特殊场景需要
* @return
*/
public String get(String httpurl, Map headers) {
if (tPool == null) {
int count = getCPUcount();
tPool = Executors.newFixedThreadPool(count);
}
Future future = tPool.submit(new MyTask(httpurl, headers));
String result = "";
try {
result = future.get();
} catch (Exception e) {
// TODO: handle exception
}
return result;
}
class MyTask implements Callable {
private String httpurl;
private Map headers;
public MyTask(String httpurl, Map headers) {
// TODO Auto-generated constructor stub
this.httpurl = httpurl;
this.headers = headers;
}
@Override
public String call() throws Exception {
// TODO Auto-generated method stub
String result = "";
URL url = null;
HttpURLConnection connection = null;
InputStreamReader in = null;
try {
url = new URL(httpurl);
connection = (HttpURLConnection) url.openConnection();
if (null != headers && headers.size() > 0) {
Iterator it = headers.keySet().iterator();
while (it.hasNext()) {
String k = it.next();
connection.setRequestProperty(k, headers.get(k));
}
}
connection.setConnectTimeout(connectionTime);
connection.setReadTimeout(readTime);
connection.connect();
in = new InputStreamReader(connection.getInputStream());
BufferedReader bufferedReader = new BufferedReader(in);
StringBuffer strBuffer = new StringBuffer();
String line = null;
while ((line = bufferedReader.readLine()) != null) {
strBuffer.append(line);
}
result = strBuffer.toString();
} catch (Exception e) {
e.printStackTrace();
} finally {
if (connection != null) {
connection.disconnect();
}
if (in != null) {
try {
in.close();
} catch (IOException e) {
e.printStackTrace();
}
}
}
return result;
}
}
}
调用：String xxx = AppThreadPool.getPool().get("http://int.dpool.sina.com.cn/iplookup/iplookup.php?format=json&ip=", null);
System.out.println("activity---" + xxx);
类里面只做了get请求访问，相信各位能看懂都能写其他。