classlib: support ReferenceQueue.remove

classlib/src/main/java/org/teavm/classlib/java/lang/ref/TReferenceQueue.java

@@ -15,8 +15,128 @@
  */
 package org.teavm.classlib.java.lang.ref;
 
+import org.teavm.classlib.PlatformDetector;
+import org.teavm.classlib.java.lang.TThread;
+import org.teavm.classlib.java.lang.TThreadInterruptHandler;
+import org.teavm.interop.Async;
+import org.teavm.interop.AsyncCallback;
+import org.teavm.platform.Platform;
+import org.teavm.platform.PlatformRunnable;
+import org.teavm.runtime.EventQueue;
+
 public class TReferenceQueue<T> {
+    private RemoveCallback firstCallback;
+    private RemoveCallback lastCallback;
+
     public TReference<T> poll() {
         return null;
     }
+
+    public TReference<T> remove() throws InterruptedException {
+        return remove(0);
+    }
+
+    @Async
+    public native TReference<T> remove(long timeout) throws InterruptedException;
+
+    public void remove(long timeout, AsyncCallback<TReference<T>> callback) {
+        var ref = poll();
+        if (ref != null) {
+            callback.complete(ref);
+        } else {
+            var callbackWrapper = new RemoveCallback(callback);
+            if (timeout != 0) {
+                callbackWrapper.id = PlatformDetector.isLowLevel()
+                        ? EventQueue.offer(callbackWrapper, timeout + System.currentTimeMillis())
+                        : Platform.schedule(callbackWrapper, (int) timeout);
+            }
+            TThread.currentThread().interruptHandler = callbackWrapper;
+            registerCallback(callbackWrapper);
+        }
+    }
+
+    private void registerCallback(RemoveCallback callback) {
+        callback.prev = lastCallback;
+        if (lastCallback != null) {
+            lastCallback.next = callback;
+        } else {
+            firstCallback = callback;
+        }
+        lastCallback = callback;
+    }
+
+    protected boolean reportNext(TReference<T> ref) {
+        if (firstCallback == null) {
+            return false;
+        }
+        var callback = firstCallback;
+        callback.complete(ref);
+        return true;
+    }
+
+    private class RemoveCallback implements EventQueue.Event, PlatformRunnable, AsyncCallback<TReference<T>>,
+            TThreadInterruptHandler {
+        RemoveCallback next;
+        RemoveCallback prev;
+        int id;
+        AsyncCallback<TReference<T>> callback;
+
+        RemoveCallback(AsyncCallback<TReference<T>> callback) {
+            this.callback = callback;
+        }
+
+        @Override
+        public void run() {
+            if (PlatformDetector.isLowLevel()) {
+                EventQueue.kill(id);
+            } else {
+                Platform.killSchedule(id);
+            }
+            complete(null);
+        }
+
+        @Override
+        public void complete(TReference<T> result) {
+            var callback = this.callback;
+            if (callback != null) {
+                remove();
+                callback.complete(result);
+            }
+        }
+
+        @Override
+        public void error(Throwable e) {
+            var callback = this.callback;
+            if (callback != null) {
+                remove();
+                callback.error(e);
+            }
+        }
+
+        @Override
+        public void interrupted() {
+            var callback = this.callback;
+            if (callback != null) {
+                remove();
+                callback.error(new InterruptedException());
+            }
+        }
+
+        private void remove() {
+            TThread.currentThread().interruptHandler = null;
+            callback = null;
+            if (prev != null) {
+                prev.next = next;
+            } else {
+                firstCallback = next;
+            }
+            if (next != null) {
+                next.prev = prev;
+            } else {
+                lastCallback = prev;
+            }
+            next = null;
+            prev = null;
+        }
+    }
 }

classlib/src/main/java/org/teavm/classlib/java/util/concurrent/TArrayBlockingQueue.java

@@ -447,7 +447,7 @@ public class TArrayBlockingQueue<E> extends TAbstractQueue<E> implements TBlocki
         TThread.currentThread().interruptHandler = handler;
     }
 
-    class WaitHandler implements PlatformRunnable, TThreadInterruptHandler, EventQueue.Event {
+    static class WaitHandler implements PlatformRunnable, TThreadInterruptHandler, EventQueue.Event {
         AsyncCallback<Boolean> callback;
         boolean complete;
         int timerId;

core/src/main/java/org/teavm/backend/javascript/intrinsics/ref/ReferenceQueueGenerator.java

@@ -16,6 +16,7 @@
 package org.teavm.backend.javascript.intrinsics.ref;
 
 import java.io.IOException;
+import java.lang.ref.Reference;
 import java.lang.ref.ReferenceQueue;
 import org.teavm.backend.javascript.codegen.SourceWriter;
 import org.teavm.backend.javascript.spi.Generator;
@@ -27,6 +28,8 @@ public class ReferenceQueueGenerator implements Generator {
     private static final FieldReference INNER_FIELD = new FieldReference(ReferenceQueue.class.getName(), "inner");
     private static final FieldReference REGISTRY_FIELD = new FieldReference(ReferenceQueue.class.getName(),
             "registry");
+    private static final MethodReference REPORT_METHOD = new MethodReference(ReferenceQueue.class,
+            "reportNext", Reference.class, boolean.class);
 
     @Override
     public void generate(GeneratorContext context, SourceWriter writer, MethodReference methodRef) throws IOException {
@@ -43,10 +46,14 @@ public class ReferenceQueueGenerator implements Generator {
     private void generateInitMethod(GeneratorContext context, SourceWriter writer) throws IOException {
         writer.append(context.getParameterName(0)).append(".").appendField(INNER_FIELD).ws().append("=")
                 .ws().append("[];").softNewLine();
+
         writer.append(context.getParameterName(0)).append(".").appendField(REGISTRY_FIELD).ws().append("=")
-                .ws().append("new $rt_globals.FinalizationRegistry(x").ws().append("=>").ws()
+                .ws().append("new $rt_globals.FinalizationRegistry(ref").ws().append("=>").appendBlockStart();
-                .append(context.getParameterName(0)).appendField(INNER_FIELD)
+        writer.appendIf().append("!").appendMethodBody(REPORT_METHOD).append("(")
-                .append(".push(x));").softNewLine();
+                .append(context.getParameterName(0)).append(",").ws().append("ref))").ws();
+        writer.append(context.getParameterName(0)).append(".").appendField(INNER_FIELD)
+                .append(".push(ref)").softNewLine();
+        writer.appendBlockEnd().append(");").softNewLine();
     }
 
     private void generatePollMethod(GeneratorContext context, SourceWriter writer) throws IOException {

core/src/main/java/org/teavm/backend/javascript/intrinsics/ref/WeakReferenceDependencyListener.java

@@ -20,31 +20,31 @@ import java.lang.ref.ReferenceQueue;
 import java.lang.ref.WeakReference;
 import org.teavm.dependency.AbstractDependencyListener;
 import org.teavm.dependency.DependencyAgent;
+import org.teavm.dependency.DependencyNode;
 import org.teavm.dependency.MethodDependency;
 import org.teavm.model.FieldReference;
 import org.teavm.model.MethodReference;
 
 public class WeakReferenceDependencyListener extends AbstractDependencyListener {
+    private DependencyNode initRef;
+
     @Override
     public void methodReached(DependencyAgent agent, MethodDependency method) {
+        initRef = agent.createNode();
         if (method.getMethod().getOwnerName().equals(WeakReference.class.getName())) {
             referenceMethodReached(agent, method);
         } else if (method.getMethod().getOwnerName().equals(ReferenceQueue.class.getName())) {
-            agent.linkField(new FieldReference(ReferenceQueue.class.getName(), "inner"));
+            queueMethodReached(agent, method);
-            agent.linkField(new FieldReference(ReferenceQueue.class.getName(), "registry"));
         }
     }
 
     private void referenceMethodReached(DependencyAgent agent, MethodDependency method) {
         switch (method.getMethod().getName()) {
             case "<init>": {
-                if (method.getParameterCount() == 2) {
+                if (method.getParameterCount() == 3) {
                     var field = agent.linkField(new FieldReference(method.getMethod().getOwnerName(), "value"));
-                    method.getVariable(1).connect(field.getValue());
+                    method.getVariable(2).connect(field.getValue());
-                    var pollResult = agent
+                    method.getVariable(1).connect(initRef);
-                            .linkMethod(new MethodReference(ReferenceQueue.class, "poll", Reference.class))
-                            .getResult();
-                    method.getVariable(0).connect(pollResult);
                 }
                 break;
             }
@@ -55,4 +55,23 @@ public class WeakReferenceDependencyListener extends AbstractDependencyListener
             }
         }
     }
+
+    private void queueMethodReached(DependencyAgent agent, MethodDependency method) {
+        switch (method.getMethod().getName()) {
+            case "poll":
+                initRef.connect(method.getResult());
+                break;
+            case "<init>":
+                agent.linkField(new FieldReference(ReferenceQueue.class.getName(), "inner"));
+                agent.linkField(new FieldReference(ReferenceQueue.class.getName(), "registry"));
+                break;
+            case "registerCallback": {
+                var reportMethod = agent.linkMethod(new MethodReference(ReferenceQueue.class,
+                        "reportNext", Reference.class, boolean.class));
+                initRef.connect(reportMethod.getVariable(1));
+                reportMethod.use();
+                break;
+            }
+        }
+    }
 }

core/src/main/java/org/teavm/backend/javascript/intrinsics/ref/WeakReferenceGenerator.java

@@ -58,7 +58,7 @@ public class WeakReferenceGenerator implements Generator {
         writer.append(context.getParameterName(2)).append(".")
                 .appendField(new FieldReference(ReferenceQueue.class.getName(), "registry"))
                 .append(".").append("register(").append(context.getParameterName(1))
-                .append(",").ws().append("value);").softNewLine();
+                .append(",").ws().append(context.getParameterName(0)).append(");").softNewLine();
         writer.appendBlockEnd();
     }
 

tests/src/test/java/org/teavm/classlib/java/lang/ref/WeakReferenceTest.java

@@ -21,6 +21,7 @@ import static org.junit.Assert.assertSame;
 import static org.junit.Assert.assertTrue;
 import java.lang.ref.ReferenceQueue;
 import java.lang.ref.WeakReference;
+import java.util.concurrent.ArrayBlockingQueue;
 import org.junit.Ignore;
 import org.junit.Test;
 import org.junit.runner.RunWith;
@@ -36,26 +37,29 @@ public class WeakReferenceTest {
 
     @Test
     @Ignore
-    public void deref() {
+    public void deref() throws InterruptedException {
         var ref = createAndTestRef(null);
 
         for (var i = 0; i < 100; ++i) {
-            lastNode = createNodes(18);
+            lastNode = createNodes(20);
+            Thread.sleep(1);
             if (ref.get() == null) {
                 break;
             }
+            assertNotNull(lastNode);
         }
         assertNull(ref.get());
     }
 
     @Test
     @Ignore
-    public void refQueue() {
+    public void refQueue() throws InterruptedException {
         var queue = new ReferenceQueue<>();
         var ref = createAndTestRef(queue);
         var hasValue = false;
         for (var i = 0; i < 100; ++i) {
-            lastNode = createNodes(18);
+            lastNode = createNodes(20);
+            Thread.sleep(1);
             var polledRef = queue.poll();
             if (polledRef != null) {
                 hasValue = true;
@@ -64,13 +68,41 @@ public class WeakReferenceTest {
             } else {
                 assertNotNull(ref.get());
             }
+            assertNotNull(lastNode);
         }
         assertTrue(hasValue);
     }
 
+    @Test
+    public void queueRemove() throws InterruptedException {
+        var queue = new ReferenceQueue<>();
+        var ref = createAndTestRef(queue);
+        var threadQueue = new ArrayBlockingQueue<>(4);
+        var thread = new Thread(() -> {
+            try {
+                threadQueue.add(queue.remove());
+            } catch (InterruptedException e) {
+                throw new RuntimeException(e);
+            }
+        });
+        thread.setDaemon(true);
+        thread.start();
+        Object value = null;
+        for (var i = 0; i < 100; ++i) {
+            lastNode = createNodes(20);
+            Thread.sleep(1);
+            value = threadQueue.poll();
+            if (value != null) {
+                break;
+            }
+            assertNotNull(lastNode);
+        }
+        assertSame(ref, value);
+    }
+
     private WeakReference<Object> createAndTestRef(ReferenceQueue<Object> queue) {
-        var obj = new byte[4 * 1024 * 1024];
+        var obj = new Object();
-        var ref = new WeakReference<Object>(obj, queue);
+        var ref = new WeakReference<>(obj, queue);
         assertSame(obj, ref.get());
         return ref;
     }
@@ -96,7 +128,6 @@ public class WeakReferenceTest {
     private class Node {
         Node left;
         Node right;
-        byte[] data = new byte[64];
 
         Node(Node left, Node right) {
             this.left = left;