我正在使用Volley库与我的数据库进行通信。我使用递归函数连续检查我的数据库，但经过一段时间似乎递归函数停止工作，我得到以下错误：
FATAL EXCEPTION: main
Process: com.example.sakis.loginregister, PID: 22637
java.lang.OutOfMemoryError: pthread_create (stack size 131072 bytes) failed: Try again
at java.lang.VMThread.create(Native Method)
at java.lang.Thread.start(Thread.java:1029)
at com.android.volley.RequestQueue.start(RequestQueue.java:145)
at com.android.volley.toolbox.Volley.newRequestQueue(Volley.java:66)
at com.android.volley.toolbox.Volley.newRequestQueue(Volley.java:78)
at com.example.sakis.loginregister.MultiPlayerActivity.func(MultiPlayerActivity.java:342)
at com.example.sakis.loginregister.MultiPlayerActivity$2.onResponse(MultiPlayerActivity.java:160)
at com.example.sakis.loginregister.MultiPlayerActivity$2.onResponse(MultiPlayerActivity.java:133)
at com.android.volley.toolbox.StringRequest.deliverResponse(StringRequest.java:60)
at com.android.volley.toolbox.StringRequest.deliverResponse(StringRequest.java:30)
at com.android.volley.ExecutorDelivery$ResponseDeliveryRunnable.run(ExecutorDelivery.java:99)
at android.os.Handler.handleCallback(Handler.java:808)
at android.os.Handler.dispatchMessage(Handler.java:103)
at android.os.Looper.loop(Looper.java:193)
at android.app.ActivityThread.main(ActivityThread.java:5292)
at java.lang.reflect.Method.invokeNative(Native Method)
at java.lang.reflect.Method.invoke(Method.java:515)
at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:824)
at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:640)
at dalvik.system.NativeStart.main(Native Method)
我认为当我没有及时得到正确的响应时，这是一个stackoverflow错误。这是我首先在onCreate方法中调用的递归函数代码：
void func(){
reject=0;
Response.Listener<String> response1Listener = new Response.Listener<String>() {
@Override
public void onResponse(final String response) {
try {
JSONObject jsonResponse = new JSONObject(response);
request = jsonResponse.getInt("request");
requestorigin = jsonResponse.getString("requestorigin");
category = jsonResponse.getInt("category");
dif_level = jsonResponse.getInt("dif_level");
number_of_questions = jsonResponse.getInt("number_of_questions");
time_of_answer = jsonResponse.getInt("time_of_answer");
if(request==0) {
func();
}
if (request == 1) {
AlertDialog.Builder alertDialogBuilder = new AlertDialog.Builder(MultiPlayerActivity.this,R.style.myBackgroundStyle);
alertDialogBuilder.setMessage("Έχεις νέο αίτημα από τον χρήστη " + requestorigin + "\n" + "Κατηγορία Ερωτήσεων: " + array_category[category]
+ "\n" + "Επίπεδο Δυσκολίας: " + array_dif_level[dif_level] + "\n" + "Αριθμός Ερωτήσεων: " + number_of_questions + "\n "
+ "Χρόνος Απάντησης: " + time_of_answer);
alertDialogBuilder.setPositiveButton("Ναι", new DialogInterface.OnClickListener() {
@Override
public void onClick(DialogInterface arg0, int arg1) {
Response.Listener<String> response1Listener = new Response.Listener<String>() {
@Override
public void onResponse(final String response) {
try {
JSONObject jsonResponse = new JSONObject(response);
} catch (JSONException e)
{
e.printStackTrace();
}
}
};
SendResponseRequest sendResponseRequest = new SendResponseRequest(username, response1Listener);
RequestQueue queue1 = Volley.newRequestQueue(MultiPlayerActivity.this);
queue1.add(sendResponseRequest);
Response.Listener<String> responseListener=new Response.Listener<String>() {
@Override
public void onResponse(String response) {
try {
JSONObject jsonResponse = new JSONObject(response);
boolean success1=jsonResponse.getBoolean("success1");
if(success1) {
Intent intent2 = new Intent(MultiPlayerActivity.this, MultiPlayerGame2Activity.class);
intent2.putExtra("username1",username);
intent2.putExtra("username2",requestorigin);
intent2.putExtra("category", category);
intent2.putExtra("dif_level", dif_level);
intent2.putExtra("number_of_questions", number_of_questions);
intent2.putExtra("time_of_answer", time_of_answer);
intent2.putExtra("level", level);
intent2.putExtra("score", score);
intent2.putExtra("music",music);
intent2.putExtra("sound",sound);
startActivity(intent2);
// android.os.Process.killProcess(android.os.Process.myPid());
finish();
}
} catch (JSONException e)
{
e.printStackTrace();
}
}
};
Back0Request back0Request = new Back0Request(username,responseListener);
RequestQueue queue = Volley.newRequestQueue(MultiPlayerActivity.this);
queue.add(back0Request);
}
});
alertDialogBuilder.setNegativeButton("Όχι", new DialogInterface.OnClickListener() {
@Override
public void onClick(DialogInterface dialog, int which) {
Response.Listener<String> response1Listener = new Response.Listener<String>() {
@Override
public void onResponse(final String response) {
try {
JSONObject jsonResponse = new JSONObject(response);
reject = jsonResponse.getInt("reject");
if(reject==1) {
func();
}
} catch (JSONException e)
{
e.printStackTrace();
}
}
};
RejectRequestRequest rejectRequestRequest = new RejectRequestRequest(username, response1Listener);
RequestQueue queue1 = Volley.newRequestQueue(MultiPlayerActivity.this);
queue1.add(rejectRequestRequest);
}
});
AlertDialog alertDialog = alertDialogBuilder.create();
alertDialog.show();
}
} catch (JSONException e)
{
e.printStackTrace();
}
}
};
//text2.setText("OK");
CheckRequest checkRequest = new CheckRequest(username, response1Listener);
/***
int socketTimeout = 30000;//30 seconds - change to what you want
RetryPolicy policy = new DefaultRetryPolicy(socketTimeout, DefaultRetryPolicy.DEFAULT_MAX_RETRIES, DefaultRetryPolicy.DEFAULT_BACKOFF_MULT);
checkRequest.setRetryPolicy(policy);
******/
RequestQueue queue1 = Volley.newRequestQueue(MultiPlayerActivity.this);
queue1.add(checkRequest);
//text3.setText("After ");
}
当我从数据库获取的变量请求值为零时，我想再次检查数据库，直到它将采用非零值。有没有更好的方法来实现这一点，所以我可以避免递归，因为它会导致一些溢出错误。
答案 0 :(得分：0)
当我使用Singleton Pattern并重新使用队列的同一实例时，问题解决了，这样可以防止出现内存不足错误：
public class MySingleton {
private static MySingleton mInstance;
private RequestQueue mRequestQueue;
private static Context mContext;
private MySingleton(Context context){
// Specify the application context
mContext = context;
// Get the request queue
mRequestQueue = getRequestQueue();
}
public static synchronized MySingleton getInstance(Context context){
// If Instance is null then initialize new Instance
if(mInstance == null){
mInstance = new MySingleton(context);
}
// Return MySingleton new Instance
return mInstance;
}
public RequestQueue getRequestQueue(){
// If RequestQueue is null the initialize new RequestQueue
if(mRequestQueue == null){
mRequestQueue = Volley.newRequestQueue(mContext.getApplicationContext());
}
// Return RequestQueue
return mRequestQueue;
}
public<T> void addToRequestQueue(Request<T> request){
// Add the specified request to the request queue
getRequestQueue().add(request);
}