RXJAVA framework's back pressure technical principles and practical application research
RXJAVA is a streaming programming library for processing asynchronous and event -based programming.It uses an observer mode and an observed stream to express asynchronous data processing.When processing asynchronous data streams, back pressure technology is an important concept that helps control the flow speed of data to avoid data producers from overwhelming data consumers.
Back pressure is a technology that sends signals to data producers to control the data stream by data consumers.In asynchronous programming, data producers may generate data at a faster speed, and consumers may not be able to process these data immediately.If there is no back pressure mechanism, these uncontrolled data may cause the memory to occupy too much, and even the system collapse.
RXJAVA uses back pressure strategies to control the speed of the data stream.Back pressure strategies can establish a communication mechanism between producers and consumers. Through this mechanism, consumers can inform producers that they can withstand the size of the data traffic.Based on these signals, producers can adjust their generating speed accordingly to make the processing of data more balanced.
RXJAVA provides several different back pressure strategies.Among them, the most commonly used is buffering and discarding strategies.In the buffer strategy, producers will store all unfinished data in memory until consumers prepare them.When consumers are ready to process data, they can obtain all buffer data at one time.In the discarding strategy, producers will simply discard those unprepared data.
Below is an example code that uses RXJAVA's back pressure strategy:
Flowable.range(1, 1000)
.onbackpressureBuffer () // Use buffer strategy
.obServeon (schedulers.io ()) // process data in the IO thread
.subscribe(new Subscriber<Integer>() {
@Override
public void onSubscribe(Subscription s) {
s.Request (Integer.max_value); // Requires to process as much data as possible
}
@Override
public void onNext(Integer integer) {
// Data processing
System.out.println(integer);
}
@Override
public void onError(Throwable t) {
// Error treatment
}
@Override
public void onComplete() {
//
}
});
In this example, by using the `OnbackpressureBuffer () method, we chose the buffer strategy to deal with back pressure.Then, we use the `Observeon ()` method to switch the data processing to the IO thread.Finally, we subscribe to the data stream through the method of `Subscripe ()`, and request as much data as possible in the method of `onsubscrip ().
Through back pressure technology, RXJAVA can better control the rate of data streams, thereby helping us avoid the problem of memory occupation and system collapse.In practical applications, we can choose the appropriate back pressure strategy based on the specific scene, or to meet specific needs by custom back pressure strategies.