java.util.ArrayDeque#clear ( )源码实例Demo

/**
 * 将更新数据与窗口中的对方流数据,根据KEY（条件）进行匹配
 * 根据是否允许Join 空流，由具体的Composer进行操作
 */
protected void compose(IEvent[] events, int streamIndex, Set<MultiKey> result)
{
    if (events == null || events.length == 0)
    {
        return;
    }
    
    ArrayDeque<IEvent[]> joinTemp = new ArrayDeque<IEvent[]>();
    for (IEvent theEvent : events)
    {
        perEventCompose(theEvent, streamIndex, joinTemp);
        
        // 如果joinTemp结果无事件，则没有任何结果
        for (IEvent[] row : joinTemp)
        {
            result.add(new MultiKey(row));
        }
        joinTemp.clear();
    }
}
 

/**
 * 针对每个更新数据，与对方流有效数据进行全匹配
 * 如果对方 流中没有有效数据，至少输出一条结果数据
 */
private void compose(IEvent[] events, int streamIndex, Set<MultiKey> result)
{
    if (events == null || events.length == 0)
    {
        return;
    }
    
    ArrayDeque<IEvent[]> joinTemp = new ArrayDeque<IEvent[]>();
    for (IEvent theEvent : events)
    {
        perEventCompose(theEvent, streamIndex, joinTemp);
        
        for (IEvent[] row : joinTemp)
        {
            result.add(new MultiKey(row));
        }
        joinTemp.clear();
    }
    
}
 

/**
 * clear removes all elements
 */
public void testClear() {
    ArrayDeque q = populatedDeque(SIZE);
    q.clear();
    assertTrue(q.isEmpty());
    assertEquals(0, q.size());
    assertTrue(q.add(new Integer(1)));
    assertFalse(q.isEmpty());
    q.clear();
    assertTrue(q.isEmpty());
}
 

/**
 * clear removes all elements
 */
public void testClear() {
    ArrayDeque q = populatedDeque(SIZE);
    q.clear();
    assertTrue(q.isEmpty());
    assertEquals(0, q.size());
    assertTrue(q.add(new Integer(1)));
    assertFalse(q.isEmpty());
    q.clear();
    assertTrue(q.isEmpty());
}
 

private void dumpBusEvents(Execution execution) throws InterruptedException {
    final ArrayDeque<ScoreEvent> eventsQueue = execution.getSystemContext().getEvents();
    if ((eventsQueue != null) && !eventsQueue.isEmpty()) {
        for (ScoreEvent eventWrapper : eventsQueue) {
            eventBus.dispatch(eventWrapper);
        }
        eventsQueue.clear();
    }
}
 

@Test
public void testFlushStopping() throws XMPPException, TigaseStringprepException {
    String recipient = "[email protected]";
    JID recp1 = JID.jidInstanceNS(recipient + "/res1");
    JID connId1 = JID.jidInstanceNS("[email protected]/recipient1-res1");
    XMPPResourceConnection session1 = getSession(connId1, recp1);

    enableCSI(session1);

    ArrayDeque<Packet> results = new ArrayDeque<>();
    Packet p = Packet.packetInstance("presence", "[email protected]/res1", recp1.toString(), StanzaType.available);
    p.setPacketTo(connId1);
    csi.filter(p, session1, null, results);

    results.clear();
    Packet m = Packet.packetInstance("message", "[email protected]/res1", recp1.toString(), StanzaType.chat);
    m.getElement().addChild(new Element("received", new String[]{ "xmlns" }, new String[] { "urn:xmpp:receipts" }));
    m.setPacketTo(connId1);
    results.offer(m);
    csi.filter(m, session1, null, results);

    results.clear();
    results.offer(m);
    results.clear();
    csi.stopped(session1, results, new HashMap<>());
    Packet[] processed = results.toArray(new Packet[results.size()]);
    Assert.assertEquals(0, processed.length);
}
 

private <T> boolean search(MimedType<T> target, ArrayDeque<PathInfo> bestMatch, ArrayDeque<PathInfo> currentPath, MimedType currentSearch, HashSet<MimedType> searched) {
    if (target.isTypeOf(currentSearch)) {
        bestMatch.clear();
        bestMatch.addAll(currentPath);
        return true;
    }

    // the current path must have potential to be better than the best match
    if (!bestMatch.isEmpty() && PathInfo.distance(currentPath) >= PathInfo.distance(bestMatch))
        return false;

    // prevent reentrancy
    if (searched.contains(currentSearch))
        return false;

    boolean found = false;
    searched.add(currentSearch);
    ConverterTransformers<Object, Object> converterTransformers = outputs.getAll(currentSearch);
    for (MimedType candidate: converterTransformers.keySet()) {
        // this simulates the mime results of a transform
        MimedType newSearch = new MimedType(candidate.type, mimeReplace(currentSearch.mime, candidate.mime));

        PathInfo path = new PathInfo();
        path.transformer = converterTransformers.get(candidate);
        path.mime = newSearch.mime;
        path.candidate = candidate;
        currentPath.addLast(path);
        try {
            found |= search(target, bestMatch, currentPath, newSearch, searched);
        }
        finally {
            currentPath.removeLast();
        }
    }

    if (found) {
        // if this resulted in a success,
        // clear this from the currentSearch list, because we know this leads
        // to a potential solution. maybe we can arrive here faster.
        searched.remove(currentSearch);
    }

    return found;
}
 

/**
 * Inspect the instructions to find details over a specific stack position.
 * 
 * @param instructions
 *            the parsed instructions
 * @param count
 *            the count of values on the stack back. 1 means the last value. 2 means the penultimate value.
 * @param javaCodePos
 *            the current code position, important to follow jumps in the code
 * @return details of the stack position
 */
static StackValue findInstructionThatPushValue( List<WasmInstruction> instructions, int count, int javaCodePos ) {
    // because there can be jumps (GOTO) we can analyze the stack only forward. If we iterate backward we will not see that we are in a jump.
    ArrayDeque<StackValue> stack = new ArrayDeque<>();
    int size = instructions.size();
    for( int i = 0; i < size; i++ ) {
        WasmInstruction instr = instructions.get( i );
        int popCount = instr.getPopCount();
        for( int p = 0; p < popCount; p++ ) {
            stack.pop();
        }
        AnyType pushValue = instr.getPushValueType();
        if( pushValue != null ) {
            StackValue el = new StackValue();
            el.idx = i;
            el.instr = instr;
            stack.push( el );
        }
        if( instr.getType() == Type.Jump ) {
            if( popCount == 0 ) { // GOTO, for example on the end of the THEN branch
                JumpInstruction jump = (JumpInstruction)instr;
                int jumpPos = jump.getJumpPosition();
                if( jumpPos > javaCodePos ) {
                    // we need a stack position inside a branch, we can remove all outside
                    stack.clear();
                } else if( jumpPos > instr.getCodePosition() ) {
                    while( ++i < size && jumpPos > instructions.get( i ).getCodePosition() ) {
                        //nothing
                    }
                    i--; // we are on the right position but the loop increment
                }
            }
        }
    }

    try {
        StackValue stackValue;
        do {
            stackValue = stack.pop();
        } while( --count > 0 );
        return stackValue;
    } catch( NoSuchElementException ex ) {
        throw new WasmException( "Push instruction not found", -1 ); // should never occur
    }
}