Java 同时运行多个Asyntask
我想实现一个程序来执行图像识别。如果图像是在本地处理的,它会发送到另一台计算机进行处理,我将Thread.sleep(1000)设置为本地处理第一个图像,其他将在localprocessing变量设置为false之前发送Java 同时运行多个Asyntask,java,android,multithreading,android-asynctask,Java,Android,Multithreading,Android Asynctask,我想实现一个程序来执行图像识别。如果图像是在本地处理的,它会发送到另一台计算机进行处理,我将Thread.sleep(1000)设置为本地处理第一个图像,其他将在localprocessing变量设置为false之前发送 private class ProcessImageTask extends AsyncTask<ImageItem, Void, ImageItem>{ @Override protected ImageItem doInBackground(Im
private class ProcessImageTask extends AsyncTask<ImageItem, Void, ImageItem>{
@Override
protected ImageItem doInBackground(ImageItem... params) {
if(localProcessing==false){
//**************processing locally*****************
localProcessing = true;
try {
Bitmap bm = BitmapFactory.decodeFile(params[0].getBitmap());
Bitmap croppedBitmap = getBitmap(getApplicationContext(), INPUT_SIZE, bm);
final List<Classifier.Recognition> results = classifier.recognizeImage(croppedBitmap);
String resultStr = results.toString();
String trimResult = resultStr.substring(resultStr.indexOf("[")+1,resultStr.indexOf("]")).trim();
String localId = params[0].getId();
trimResult = trimResult.substring(0,trimResult.indexOf(")")) + " likely)";
Bitmap thumbnail = getBitmap(getApplicationContext(), 50, bm);
ImageItem tmp = new ImageItem(localId, imgToString(thumbnail), trimResult);
Thread.currentThread();
Thread.sleep(1000);
localProcessing = false;
return tmp;
} catch (IOException e) {
e.printStackTrace();
} catch (InterruptedException e) {
e.printStackTrace();
}
} else {
//****************processing on server*************************
try {
String ip = strIP;
int port = 8195;
Bitmap bm = BitmapFactory.decodeFile(params[0].getBitmap());
Bitmap croppedBitmap = getBitmap(getApplicationContext(), INPUT_SIZE, bm);
String encodedImage = "/ID-BEGIN/" + ID + "/ID-END" + imgToString(croppedBitmap);
try {
//**********Send request to server*********
Socket socket = new Socket(ip,port);
DataInputStream dis = new DataInputStream(socket.getInputStream());
DataOutputStream dout = new DataOutputStream(socket.getOutputStream());
byte [] messageToServer = encodedImage.getBytes();
dout.writeInt(messageToServer.length);
dout.write(messageToServer);
//Receive response from server
int length = dis.readInt();
if(length>0) {
byte [] message = new byte[length];
dis.readFully(message, 0, message.length);
String response = new String(message);
//Handler updateHandler.post(new updateUIThread(response));
Bitmap thumbnail = getBitmap(getApplicationContext(), 50, bm);
ImageItem tmp = new ImageItem(params[0].getId(),imgToString(thumbnail), extractServerMessage(response)+"@@");
return tmp;
}
socket.close();
} catch (IOException e) {
e.printStackTrace();
}
} catch (IOException e) {
e.printStackTrace();
}
}
return null;
}
@Override
protected void onPostExecute(ImageItem imageItem) {
super.onPostExecute(imageItem);
}
}
私有类ProcessImageTask扩展了AsyncTask{
@凌驾
受保护的ImageItem doInBackground(ImageItem…参数){
if(localProcessing==false){
//**************本地处理*****************
localProcessing=true;
试一试{
位图bm=BitmapFactory.decodeFile(参数[0].getBitmap());
位图裁剪位图=getBitmap(getApplicationContext(),输入大小,bm);
最终列表结果=分类器.recognizeImage(裁剪位图);
字符串resultStr=results.toString();
String trimsresult=resultStr.substring(resultStr.indexOf(“[”)+1,resultStr.indexOf(“])。trim();
字符串localId=params[0]。getId();
trimResult=trimResult.substring(0,trimResult.indexOf(“)”)+“可能)”;
位图缩略图=getBitmap(getApplicationContext(),50,bm);
ImageItem tmp=新ImageItem(本地化、图像缩放(缩略图)、修剪结果);
Thread.currentThread();
睡眠(1000);
localProcessing=false;
返回tmp;
}捕获(IOE异常){
e、 printStackTrace();
}捕捉(中断异常e){
e、 printStackTrace();
}
}否则{
//****************在服务器上处理*************************
试一试{
字符串ip=条带;
int端口=8195;
位图bm=BitmapFactory.decodeFile(参数[0].getBitmap());
位图裁剪位图=getBitmap(getApplicationContext(),输入大小,bm);
字符串encodedImage=“/ID-BEGIN/”+ID+“/ID-END”+imgToString(裁剪位图);
试一试{
//**********向服务器发送请求*********
插座=新插座(ip,端口);
DataInputStream dis=新的DataInputStream(socket.getInputStream());
DataOutputStream dout=新的DataOutputStream(socket.getOutputStream());
byte[]messageToServer=encodedImage.getBytes();
dout.writeInt(messageToServer.length);
dout.write(messageToServer);
//从服务器接收响应
int length=dis.readInt();
如果(长度>0){
字节[]消息=新字节[长度];
dis.readFully(消息,0,消息长度);
字符串响应=新字符串(消息);
//Handler updateHandler.post(新的updateUIThread(响应));
位图缩略图=getBitmap(getApplicationContext(),50,bm);
ImageItem tmp=new ImageItem(参数[0].getId(),imgToString(缩略图),extractServerMessage(响应)+“@”);
返回tmp;
}
socket.close();
}捕获(IOE异常){
e、 printStackTrace();
}
}捕获(IOE异常){
e、 printStackTrace();
}
}
返回null;
}
@凌驾
受保护的void onPostExecute(ImageItem ImageItem){
super.onPostExecute(imageItem);
}
}
我意识到它是按顺序工作的,你能告诉我,即使我设置了线程,我也应该如何修复并使不同的任务同时工作
非常感谢。您可能希望在线程池中同时执行所有异步任务
asyncTask1.executeOnExecutor(AsyncTask.THREAD_POOL_EXECUTOR, ....);
AsyncTask.THREAD\u POOL\u EXECUTOR
是一个常量EXECUTOR
。如果您对AsyncTask的线程池不满意。通过这样做,您可以创建自己的线程池
Executor myThreadPool = Executors.newFixedThreadPool(numOfPools);
通常,numofools
由Runtime.getRuntime().availableProcessors()从可用处理器获取
需要多少线程仍然取决于您。注意电池的使用。更多的计算能力,更多的电池。只是提醒一下。您如何执行此任务?