我收到以下警告:“Android.Annotation.NonNull”在“Android.Annotation”中不是公共的。无法从外部包访问
“Android.Annotation.Nullable”在“Android.Annotation”中不是公共得。 无法从外部包访问。
我还收到此警告:无法解析符号“UnsupportedAppusage”。
我尝试了这两个导入，基于线程'android.annotation.nonnull'在'android.annotation‘中不是公共的建议。 无法从外部包访问，但它们没有帮助。import androidx.annotation.NonNull;
import androidx.annotation.Nullable;
下面是我在handler.java-file中的全部代码(我去掉了所有注释):package android.os;
import androidx.annotation.NonNull;
import androidx.annotation.*;
import androidx.annotation.Nullable;
import androidx.annotation.UnsupportedAppUsage;
import android.util.Log;
import android.util.Printer;
import java.lang.reflect.Modifier;
public class Handler {
private static final boolean FIND_POTENTIAL_LEAKS = false;
private static final String TAG = "Handler";
private static Handler MAIN_THREAD_HANDLER = null;
public interface Callback {
boolean handleMessage(@NonNull Message msg);
}
public void handleMessage(@NonNull Message msg) {
}
public void dispatchMessage(@NonNull Message msg) {
if (msg.callback != null) {
handleCallback(msg);
} else {
if (mCallback != null) {
if (mCallback.handleMessage(msg)) {
return;
}
}
handleMessage(msg);
}
}
public Handler() {
this(null, false);
}
public Handler(@Nullable Callback callback) {
this(callback, false);
}
public Handler(@NonNull Looper looper) {
this(looper, null, false);
}
public Handler(@NonNull Looper looper, @Nullable Callback callback) {
this(looper, callback, false);
}
@UnsupportedAppUsage
public Handler(boolean async) {
this(null, async);
}
public Handler(@Nullable Callback callback, boolean async) {
if (FIND_POTENTIAL_LEAKS) {
final Class extends Handler> klass = getClass();
if ((klass.isAnonymousClass() || klass.isMemberClass() || klass.isLocalClass()) &&
(klass.getModifiers() & Modifier.STATIC) == 0) {
Log.w(TAG, "The following Handler class should be static or leaks might occur: " +
klass.getCanonicalName());
}
}
mLooper = Looper.myLooper();
if (mLooper == null) {
throw new RuntimeException(
"Can't create handler inside thread " + Thread.currentThread()
+ " that has not called Looper.prepare()");
}
mQueue = mLooper.mQueue;
mCallback = callback;
mAsynchronous = async;
}
@UnsupportedAppUsage
public Handler(@NonNull Looper looper, @Nullable Callback callback, boolean async) {
mLooper = looper;
mQueue = looper.mQueue;
mCallback = callback;
mAsynchronous = async;
}
@NonNull
public static Handler createAsync(@NonNull Looper looper) {
if (looper == null) throw new NullPointerException("looper must not be null");
return new Handler(looper, null, true);
}
@NonNull
public static Handler createAsync(@NonNull Looper looper, @NonNull Callback callback) {
if (looper == null) throw new NullPointerException("looper must not be null");
if (callback == null) throw new NullPointerException("callback must not be null");
return new Handler(looper, callback, true);
}
@UnsupportedAppUsage
@NonNull
public static Handler getMain() {
if (MAIN_THREAD_HANDLER == null) {
MAIN_THREAD_HANDLER = new Handler(Looper.getMainLooper());
}
return MAIN_THREAD_HANDLER;
}
@NonNull
public static Handler mainIfNull(@Nullable Handler handler) {
return handler == null ? getMain() : handler;
}
@NonNull
public String getTraceName(@NonNull Message message) {
final StringBuilder sb = new StringBuilder();
sb.append(getClass().getName()).append(": ");
if (message.callback != null) {
sb.append(message.callback.getClass().getName());
} else {
sb.append("#").append(message.what);
}
return sb.toString();
}
@NonNull
public String getMessageName(@NonNull Message message) {
if (message.callback != null) {
return message.callback.getClass().getName();
}
return "0x" + Integer.toHexString(message.what);
}
@NonNull
public final Message obtainMessage()
{
return Message.obtain(this);
}
@NonNull
public final Message obtainMessage(int what)
{
return Message.obtain(this, what);
}
@NonNull
public final Message obtainMessage(int what, @Nullable Object obj) {
return Message.obtain(this, what, obj);
}
@NonNull
public final Message obtainMessage(int what, int arg1, int arg2)
{
return Message.obtain(this, what, arg1, arg2);
}
@NonNull
public final Message obtainMessage(int what, int arg1, int arg2, @Nullable Object obj) {
return Message.obtain(this, what, arg1, arg2, obj);
}
public final boolean post(@NonNull Runnable r) {
return sendMessageDelayed(getPostMessage(r), 0);
}
public final boolean postAtTime(@NonNull Runnable r, long uptimeMillis) {
return sendMessageAtTime(getPostMessage(r), uptimeMillis);
}
public final boolean postAtTime(
@NonNull Runnable r, @Nullable Object token, long uptimeMillis) {
return sendMessageAtTime(getPostMessage(r, token), uptimeMillis);
}
public final boolean postDelayed(@NonNull Runnable r, long delayMillis) {
return sendMessageDelayed(getPostMessage(r), delayMillis);
}
public final boolean postDelayed(Runnable r, int what, long delayMillis) {
return sendMessageDelayed(getPostMessage(r).setWhat(what), delayMillis);
}
public final boolean postDelayed(
@NonNull Runnable r, @Nullable Object token, long delayMillis) {
return sendMessageDelayed(getPostMessage(r, token), delayMillis);
}
public final boolean postAtFrontOfQueue(@NonNull Runnable r) {
return sendMessageAtFrontOfQueue(getPostMessage(r));
}
public final boolean runWithScissors(@NonNull Runnable r, long timeout) {
if (r == null) {
throw new IllegalArgumentException("runnable must not be null");
}
if (timeout < 0) {
throw new IllegalArgumentException("timeout must be non-negative");
}
if (Looper.myLooper() == mLooper) {
r.run();
return true;
}
BlockingRunnable br = new BlockingRunnable(r);
return br.postAndWait(this, timeout);
}
public final void removeCallbacks(@NonNull Runnable r) {
mQueue.removeMessages(this, r, null);
}
public final void removeCallbacks(@NonNull Runnable r, @Nullable Object token) {
mQueue.removeMessages(this, r, token);
}
public final boolean sendMessage(@NonNull Message msg) {
return sendMessageDelayed(msg, 0);
}
public final boolean sendEmptyMessage(int what)
{
return sendEmptyMessageDelayed(what, 0);
}
public final boolean sendEmptyMessageDelayed(int what, long delayMillis) {
Message msg = Message.obtain();
msg.what = what;
return sendMessageDelayed(msg, delayMillis);
}
public final boolean sendEmptyMessageAtTime(int what, long uptimeMillis) {
Message msg = Message.obtain();
msg.what = what;
return sendMessageAtTime(msg, uptimeMillis);
}
public final boolean sendMessageDelayed(@NonNull Message msg, long delayMillis) {
if (delayMillis < 0) {
delayMillis = 0;
}
return sendMessageAtTime(msg, SystemClock.uptimeMillis() + delayMillis);
}
public boolean sendMessageAtTime(@NonNull Message msg, long uptimeMillis) {
MessageQueue queue = mQueue;
if (queue == null) {
RuntimeException e = new RuntimeException(
this + " sendMessageAtTime() called with no mQueue");
Log.w("Looper", e.getMessage(), e);
return false;
}
return enqueueMessage(queue, msg, uptimeMillis);
}
public final boolean sendMessageAtFrontOfQueue(@NonNull Message msg) {
MessageQueue queue = mQueue;
if (queue == null) {
RuntimeException e = new RuntimeException(
this + " sendMessageAtTime() called with no mQueue");
Log.w("Looper", e.getMessage(), e);
return false;
}
return enqueueMessage(queue, msg, 0);
}
public final boolean executeOrSendMessage(@NonNull Message msg) {
if (mLooper == Looper.myLooper()) {
dispatchMessage(msg);
return true;
}
return sendMessage(msg);
}
private boolean enqueueMessage(@NonNull MessageQueue queue, @NonNull Message msg,
long uptimeMillis) {
msg.target = this;
msg.workSourceUid = ThreadLocalWorkSource.getUid();
if (mAsynchronous) {
msg.setAsynchronous(true);
}
return queue.enqueueMessage(msg, uptimeMillis);
}
public final void removeMessages(int what) {
mQueue.removeMessages(this, what, null);
}
public final void removeMessages(int what, @Nullable Object object) {
mQueue.removeMessages(this, what, object);
}
public final void removeCallbacksAndMessages(@Nullable Object token) {
mQueue.removeCallbacksAndMessages(this, token);
}
public final boolean hasMessages(int what) {
return mQueue.hasMessages(this, what, null);
}
public final boolean hasMessagesOrCallbacks() {
return mQueue.hasMessages(this);
}
public final boolean hasMessages(int what, @Nullable Object object) {
return mQueue.hasMessages(this, what, object);
}
public final boolean hasCallbacks(@NonNull Runnable r) {
return mQueue.hasMessages(this, r, null);
}
@NonNull
public final Looper getLooper() {
return mLooper;
}
public final void dump(@NonNull Printer pw, @NonNull String prefix) {
pw.println(prefix + this + " @ " + SystemClock.uptimeMillis());
if (mLooper == null) {
pw.println(prefix + "looper uninitialized");
} else {
mLooper.dump(pw, prefix + " ");
}
}
public final void dumpMine(@NonNull Printer pw, @NonNull String prefix) {
pw.println(prefix + this + " @ " + SystemClock.uptimeMillis());
if (mLooper == null) {
pw.println(prefix + "looper uninitialized");
} else {
mLooper.dump(pw, prefix + " ", this);
}
}
@Override
public String toString() {
return "Handler (" + getClass().getName() + ") {"
+ Integer.toHexString(System.identityHashCode(this))
+ "}";
}
@UnsupportedAppUsage
final IMessenger getIMessenger() {
synchronized (mQueue) {
if (mMessenger != null) {
return mMessenger;
}
mMessenger = new MessengerImpl();
return mMessenger;
}
}
private final class MessengerImpl extends IMessenger.Stub {
public void send(Message msg) {
msg.sendingUid = Binder.getCallingUid();
Handler.this.sendMessage(msg);
}
}
private static Message getPostMessage(Runnable r) {
Message m = Message.obtain();
m.callback = r;
return m;
}
@UnsupportedAppUsage
private static Message getPostMessage(Runnable r, Object token) {
Message m = Message.obtain();
m.obj = token;
m.callback = r;
return m;
}
private static void handleCallback(Message message) {
message.callback.run();
}
@UnsupportedAppUsage
final Looper mLooper;
final MessageQueue mQueue;
@UnsupportedAppUsage
final Callback mCallback;
final boolean mAsynchronous;
@UnsupportedAppUsage
IMessenger mMessenger;
private static final class BlockingRunnable implements Runnable {
private final Runnable mTask;
private boolean mDone;
public BlockingRunnable(Runnable task) {
mTask = task;
}
@Override
public void run() {
try {
mTask.run();
} finally {
synchronized (this) {
mDone = true;
notifyAll();
}
}
}
public boolean postAndWait(Handler handler, long timeout) {
if (!handler.post(this)) {
return false;
}
synchronized (this) {
if (timeout > 0) {
final long expirationTime = SystemClock.uptimeMillis() + timeout;
while (!mDone) {
long delay = expirationTime - SystemClock.uptimeMillis();
if (delay <= 0) {
return false; // timeout
}
try {
wait(delay);
} catch (InterruptedException ex) {
}
}
} else {
while (!mDone) {
try {
wait();
} catch (InterruptedException ex) {
}
}
}
}
return true;
}
}
}
