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Android如何調(diào)整線程調(diào)用棧大小

更新時(shí)間：2020年10月20日 15:02:26 作者：默默的點(diǎn)滴

這篇文章主要介紹了Android如何調(diào)整線程調(diào)用棧大小，幫助大家更好的進(jìn)行Android開(kāi)發(fā)，完善自身程序，感興趣的朋友可以了解下

在常規(guī)的Android開(kāi)發(fā)過(guò)程中，隨著業(yè)務(wù)邏輯越來(lái)越復(fù)雜，調(diào)用棧可能會(huì)越來(lái)越深，難免會(huì)遇到調(diào)用棧越界的情況，這種情況下，就需要調(diào)整線程棧的大小。

當(dāng)然，主要還是增大線程棧大小，尤其是存在jni調(diào)用的情況下，C++層的棧開(kāi)銷有時(shí)候是非常恐怖的，比如說(shuō)遞歸調(diào)用。

這就需要分三種情況，主線程，自定義線程池，AsyncTask。

主線程的線程棧是沒(méi)有辦法進(jìn)行修改的，這個(gè)沒(méi)辦法處理。

針對(duì)線程池的情況，需要在創(chuàng)建線程的時(shí)候，調(diào)用構(gòu)造函數(shù)

public Thread(@RecentlyNullable ThreadGroup group, @RecentlyNullable Runnable target, @RecentlyNonNull String name, long stackSize)

通過(guò)設(shè)置stackSize參數(shù)來(lái)解決問(wèn)題。

參考代碼如下：

import android.support.annotation.NonNull;
import android.util.Log;

import java.util.concurrent.ThreadFactory;

/**
 * A ThreadFactory implementation which create new threads for the thread pool.
 */
public class SimpleThreadFactory implements ThreadFactory {
  private static final String TAG = "SimpleThreadFactory";
  private final static ThreadGroup group = new ThreadGroup("SimpleThreadFactoryGroup");
  // 工作線程堆棧大小調(diào)整為2MB
  private final static int workerStackSize = 2 * 1024 * 1024;

  @Override
  public Thread newThread(@NonNull final Runnable runnable) {
    final Thread thread = new Thread(group, runnable, "PoolWorkerThread", workerStackSize);
    // A exception handler is created to log the exception from threads
    thread.setUncaughtExceptionHandler(new Thread.UncaughtExceptionHandler() {
      @Override
      public void uncaughtException(@NonNull Thread thread, @NonNull Throwable ex) {
        Log.e(TAG, thread.getName() + " encountered an error: " + ex.getMessage());
      }
    });

    return thread;
  }
}

import android.support.annotation.AnyThread;
import android.support.annotation.NonNull;
import android.support.annotation.Nullable;
import android.util.Log;

import java.util.concurrent.BlockingQueue;
import java.util.concurrent.Callable;
import java.util.concurrent.ExecutorService;
import java.util.concurrent.Future;
import java.util.concurrent.LinkedBlockingQueue;
import java.util.concurrent.ThreadPoolExecutor;
import java.util.concurrent.TimeUnit;

/**
 * A Singleton thread pool
 */
public class ThreadPool {
  private static final String TAG = "ThreadPool";
  private static final int KEEP_ALIVE_TIME = 1;
  private static volatile ThreadPool sInstance = null;
  private static int NUMBER_OF_CORES = Runtime.getRuntime().availableProcessors();
  private final ExecutorService mExecutor;
  private final BlockingQueue<Runnable> mTaskQueue;

  // Made constructor private to avoid the class being initiated from outside
  private ThreadPool() {
    // initialize a queue for the thread pool. New tasks will be added to this queue
    mTaskQueue = new LinkedBlockingQueue<>();

    Log.d(TAG, "Available cores: " + NUMBER_OF_CORES);

    mExecutor = new ThreadPoolExecutor(NUMBER_OF_CORES, NUMBER_OF_CORES * 2, KEEP_ALIVE_TIME, TimeUnit.SECONDS, mTaskQueue, new SimpleThreadFactory());
  }

  @NonNull
  @AnyThread
  public static ThreadPool getInstance() {
    if (null == sInstance) {
      synchronized (ThreadPool.class) {
        if (null == sInstance) {
          sInstance = new ThreadPool();
        }
      }
    }
    return sInstance;
  }

  private boolean isThreadPoolAlive() {
    return (null != mExecutor) && !mExecutor.isTerminated() && !mExecutor.isShutdown();
  }

  @Nullable
  @AnyThread
  public <T> Future<T> submitCallable(@NonNull final Callable<T> c) {
    synchronized (this) {
      if (isThreadPoolAlive()) {
        return mExecutor.submit(c);
      }
    }
    return null;
  }

  @Nullable
  @AnyThread
  public Future<?> submitRunnable(@NonNull final Runnable r) {
    synchronized (this) {
      if (isThreadPoolAlive()) {
        return mExecutor.submit(r);
      }
    }
    return null;
  }

  /* Remove all tasks in the queue and stop all running threads
   */
  @AnyThread
  public void shutdownNow() {
    synchronized (this) {
      mTaskQueue.clear();
      if ((!mExecutor.isShutdown()) && (!mExecutor.isTerminated())) {
        mExecutor.shutdownNow();
      }
    }
  }
}

針對(duì)AsyncTask的情況，一般是通過(guò)調(diào)用

public final AsyncTask<Params, Progress, Result> executeOnExecutor(Executor exec, Params... params)

指定線程池來(lái)運(yùn)行，在特定的線程池中調(diào)整線程棧的大小。

參考代碼如下：

import android.os.AsyncTask;
import android.support.annotation.AnyThread;
import android.support.annotation.NonNull;
import android.util.Log;

import java.util.concurrent.BlockingQueue;
import java.util.concurrent.ExecutorService;
import java.util.concurrent.LinkedBlockingQueue;
import java.util.concurrent.ThreadPoolExecutor;
import java.util.concurrent.TimeUnit;

public abstract class AsyncTaskEx<Params, Progress, Result> extends AsyncTask<Params, Progress, Result> {

  private static final String TAG = "AsyncTaskEx";
  private static final int KEEP_ALIVE_TIME = 1;
  private static volatile ThreadPool sInstance = null;
  private static int NUMBER_OF_CORES = Runtime.getRuntime().availableProcessors();
  private final ExecutorService mExecutor;
  private final BlockingQueue<Runnable> mTaskQueue;

  public AsyncTaskEx() {
    // initialize a queue for the thread pool. New tasks will be added to this queue
    mTaskQueue = new LinkedBlockingQueue<>();

    Log.d(TAG, "Available cores: " + NUMBER_OF_CORES);

    mExecutor = new ThreadPoolExecutor(NUMBER_OF_CORES, NUMBER_OF_CORES * 2, KEEP_ALIVE_TIME, TimeUnit.SECONDS, mTaskQueue, new SimpleThreadFactory());
  }

  public AsyncTask<Params, Progress, Result> executeAsync(@NonNull final Params... params) {
    return super.executeOnExecutor(mExecutor, params);
  }

  /* Remove all tasks in the queue and stop all running threads
   */
  @AnyThread
  public void shutdownNow() {
    synchronized (this) {
      mTaskQueue.clear();
      if ((!mExecutor.isShutdown()) && (!mExecutor.isTerminated())) {
        mExecutor.shutdownNow();
      }
    }
  }
}

參考鏈接