Android 執行緒優化知識點學習

public class MyRunnable implements Runnable {<!-- -->
	@Override
	public void run() {<!-- -->
		Process.setThreadPriority(Process.THREAD_PRIORITY_DEFAULT)
	}
}
// 附上 setThreadPriority() 檔案說明
/**
 * Set the priority of the calling thread, based on Linux priorities.  See
 * {@link #setThreadPriority(int, int)} for more information.
 * 
 * @param priority A Linux priority level, from -20 for highest scheduling
 * priority to 19 for lowest scheduling priority.
 * 
 * @throws IllegalArgumentException Throws IllegalArgumentException if
 * &lt;var&gt;tid&lt;/var&gt; does not exist.
 * @throws SecurityException Throws SecurityException if your process does
 * not have permission to modify the given thread, or to use the given
 * priority.
 * 
 * @see #setThreadPriority(int, int)
 */
public static final native void setThreadPriority(int priority)
        throws IllegalArgumentException, SecurityException;

public class Process {
    /**
     * Standard priority of application threads.
     * Use with {@link #setThreadPriority(int)} and
     * {@link #setThreadPriority(int, int)}, <b>not</b> with the normal
     * {@link java.lang.Thread} class.
     */
	public static final int THREAD_PRIORITY_DEFAULT = 0;
    /**
     * Lowest available thread priority.  Only for those who really, really
     * don't want to run if anything else is happening.
     * Use with {@link #setThreadPriority(int)} and
     * {@link #setThreadPriority(int, int)}, <b>not</b> with the normal
     * {@link java.lang.Thread} class.
     */
    public static final int THREAD_PRIORITY_LOWEST = 19;	
    /**
     * Standard priority background threads.  This gives your thread a slightly
     * lower than normal priority, so that it will have less chance of impacting
     * the responsiveness of the user interface.
     * Use with {@link #setThreadPriority(int)} and
     * {@link #setThreadPriority(int, int)}, <b>not</b> with the normal
     * {@link java.lang.Thread} class.
     */
    public static final int THREAD_PRIORITY_BACKGROUND = 10;    
    /**
     * Standard priority of threads that are currently running a user interface
     * that the user is interacting with.  Applications can not normally
     * change to this priority; the system will automatically adjust your
     * application threads as the user moves through the UI.
     * Use with {@link #setThreadPriority(int)} and
     * {@link #setThreadPriority(int, int)}, <b>not</b> with the normal
     * {@link java.lang.Thread} class.
     */
    public static final int THREAD_PRIORITY_FOREGROUND = -2;
    /**
     * Standard priority of system display threads, involved in updating
     * the user interface.  Applications can not
     * normally change to this priority.
     * Use with {@link #setThreadPriority(int)} and
     * {@link #setThreadPriority(int, int)}, <b>not</b> with the normal
     * {@link java.lang.Thread} class.
     */
    public static final int THREAD_PRIORITY_DISPLAY = -4;    
    /**
     * Standard priority of the most important display threads, for compositing
     * the screen and retrieving input events.  Applications can not normally
     * change to this priority.
     * Use with {@link #setThreadPriority(int)} and
     * {@link #setThreadPriority(int, int)}, <b>not</b> with the normal
     * {@link java.lang.Thread} class.
     */
    public static final int THREAD_PRIORITY_URGENT_DISPLAY = -8;
    /**
     * Standard priority of video threads.  Applications can not normally
     * change to this priority.
     * Use with {@link #setThreadPriority(int)} and
     * {@link #setThreadPriority(int, int)}, <b>not</b> with the normal
     * {@link java.lang.Thread} class.
     */
    public static final int THREAD_PRIORITY_VIDEO = -10;
    /**
     * Standard priority of audio threads.  Applications can not normally
     * change to this priority.
     * Use with {@link #setThreadPriority(int)} and
     * {@link #setThreadPriority(int, int)}, <b>not</b> with the normal
     * {@link java.lang.Thread} class.
     */
    public static final int THREAD_PRIORITY_AUDIO = -16;
    /**
     * Standard priority of the most important audio threads.
     * Applications can not normally change to this priority.
     * Use with {@link #setThreadPriority(int)} and
     * {@link #setThreadPriority(int, int)}, <b>not</b> with the normal
     * {@link java.lang.Thread} class.
     */
    public static final int THREAD_PRIORITY_URGENT_AUDIO = -19;
    /**
     * Minimum increment to make a priority more favorable.
     */
    public static final int THREAD_PRIORITY_MORE_FAVORABLE = -1;
    /**
     * Minimum increment to make a priority less favorable.
     */
    public static final int THREAD_PRIORITY_LESS_FAVORABLE = +1;    
}

Single.just(xxx)
	.subscribeOn(Schedulers.IO) // 指定工作執行緒型別為 IO 密集型
	.observeOn(AndroidSchedulers.mainThread()) // 指定下游接收所線上程
	.subscribe();

public class ThreadPoolUtils {
    //建立定長執行緒池，核心數為5
    private static ExecutorService mService = Executors.newFixedThreadPool(5, new ThreadFactory() {
        @Override
        public Thread newThread(Runnable runnable) {
            Thread thread = new Thread(runnable,"ThreadPoolUtils");//設定執行緒名
            Process.setThreadPriority(Process.THREAD_PRIORITY_BACKGROUND); //設定執行緒優先順序
            return thread;
        }
    });
    //獲取全域性的執行緒池
    public static ExecutorService getService(){
        return mService;
    }
}

        //使用全域性統一的執行緒池
        ThreadPoolUtils.getService().execute(new Runnable() {
            @Override
            public void run() {
                Process.setThreadPriority(Process.THREAD_PRIORITY_DEFAULT); //修改執行緒優先順序
                String oldName = Thread.currentThread().getName();
                Thread.currentThread().setName("Jarchie"); //修改執行緒名稱
                Log.i("MainActivity","");
                Thread.currentThread().setName(oldName); //將原有名稱改回去
            }
        });

    @Override
    protected void attachBaseContext(Context base) {
        super.attachBaseContext(base);
        //Hook Thread類別建構函式,兩個引數：需要Hook的類，MethodHook的回撥
        DexposedBridge.hookAllConstructors(Thread.class, new XC_MethodHook() {
            //afterHookedMethod是Hook此方法之後給我們的回撥
            @Override
            protected void afterHookedMethod(MethodHookParam param) throws Throwable {
                super.afterHookedMethod(param); //Hook完成之後會回撥到這裡
                //實現自己的邏輯，param.thisObject可以拿到執行緒物件
                Thread thread = (Thread) param.thisObject;
                //Log.getStackTraceString列印當前的呼叫棧資訊
                Log.i(thread.getName() + "stack", Log.getStackTraceString(new Throwable()));
            }
        });
    }

public class LogUtils {
    private static ExecutorService mExecutorService;
    public static void setExecutor(ExecutorService executorService){
        mExecutorService = executorService;
    }
    public static final String TAG = "Jarchie";
    public static void i(String msg){
        if(Utils.isMainProcess(BaseApp.getApplication())){
            Log.i(TAG,msg);
        }
        // 非同步操作
        if(mExecutorService != null){
            mExecutorService.execute(() -> {
                ...
            });
        }else {
            //使用原有的
            ...
        }
    }
}

    //獲取CPU的核心數
    private int CPUCOUNT = Runtime.getRuntime().availableProcessors();
    //cpu執行緒池，核心數大小需要和cpu核心數相關聯，這裡簡單的將它們保持一致了
    private ThreadPoolExecutor cpuExecutor = new ThreadPoolExecutor(CPUCOUNT, CPUCOUNT,
            30, TimeUnit.SECONDS, new LinkedBlockingDeque<>(), sThreadFactory);
    //IO執行緒池，核心數64，這個數量可以針對自身專案再確定
    private ThreadPoolExecutor iOExecutor = new ThreadPoolExecutor(64, 64,
            30, TimeUnit.SECONDS, new LinkedBlockingDeque<>(), sThreadFactory);
    //這裡面使用了一個count作為標記
    private static final ThreadFactory sThreadFactory = new ThreadFactory() {
        private final AtomicInteger mCount = new AtomicInteger(1);
        public Thread newThread(Runnable runnable) {
            return new Thread(runnable, "ThreadPoolUtils #" + mCount.getAndIncrement());
        }
    };