=0,但是当前线程是持有锁线程,直接重入 elseif (current == getExclusiveOwnerThread()) { //state状态+1 int nextc = c + acquires; if (nextc < 0) // overflow thrownew Error("Maximum lock count exceeded"); //设置state状态,此处不需要cas,因为持有锁的线程只有一个 setState(nextc); return...
if-else-if statement is used when we need to check multiple conditions. In this statement we have only one “if” and one “else”, however we can have multiple “else if”. It is also known asif else if ladder. This is how it looks: if(condition_1){/*if condition_1 is true ex...
第一步:创建自定义条件类 在这一阶段,我们需要创建一个自定义条件类,继承自Condition接口。 importorg.springframework.context.annotation.Condition;importorg.springframework.context.annotation.ConditionContext;importorg.springframework.core.type.AnnotatedTypeMetadata;publicclassMyConditionimplementsCondition{@Overridepubl...
The usual well-known example is that of the producer/consumer, because the producer should wait for the consumer if the consumer’s queue is full, and the consumer should wait for the producer when empty. This requirement can be addressed through shared state and condition queues, but you ...
if M:Java.Util.Concurrent.Locks.AbstractQueuedSynchronizer.get_IsHeldExclusively returns false Remarks Returns a collection containing those threads that may be waiting on this Condition. Implements AbstractQueuedSynchronizer#getWaitingThreads(ConditionObject). Java documentation for java.uti...
* The method to call to exercise the parser from other Java programs. * It returns an error code. See how the main program above uses * this method. */ public static int mainProgram(String args[]) throws Exception { if (args.length == 1 && args[args.length -1].equalsIgnoreCase("-...
However, if a non-default border is set on the text component, it is that Border object's responsibility to create the appropriate margin space (else this property will effectively be ignored). This causes a redraw of the component. A PropertyChange event ("margin") is sent to all ...
7.3. The else clause Sometimes we want a program to do one thing if the condition is true and another thing if the condition is false. In this case the else keyword comes in handy. if(<thisIsTrue>) { <statementsToDoIfTrue> } else { <statementsToDoIfFalse> } Figure 7.3 contains a ...
The compiler chooses the variant of the comparison instruction for the appropriate type that produces the same result whether the comparison fails on non-NaN values or encounters a NaN. For instance: int lessThan100(double d) { if (d < 100.0) { return 1; } else { return -1; } } ...
example, if a Java applet is not allowed to write or read to a user's hard drive, we say it is playing in the sandbox. All Java applets are restricted to the sandbox by default, so you shouldn't need to worry about changing any settings with your e-mail programs to enforce this ...