RxJava:如何使代码异步工作?
如果我对异步工作的结论有误,请指正我,并给出如何异步工作的建议 此代码用于设置网格单元中的计算结果。 我假设异步工作应该按部分显示网格单元。因此,如果我们有8个核心,我们可以看到8个单元显示,在一段时间内,另一个8,以此类推(如果我设置了一些时间延迟)。但就目前而言,结果是细胞显示变得一个接一个 型号:RxJava:如何使代码异步工作?,java,android,rx-java,rx-java3,Java,Android,Rx Java,Rx Java3,如果我对异步工作的结论有误,请指正我,并给出如何异步工作的建议 此代码用于设置网格单元中的计算结果。 我假设异步工作应该按部分显示网格单元。因此,如果我们有8个核心,我们可以看到8个单元显示,在一段时间内,另一个8,以此类推(如果我设置了一些时间延迟)。但就目前而言,结果是细胞显示变得一个接一个 型号: public class ListRepository implements ListRepositoryInterface { private final Integer insertValu
public class ListRepository implements ListRepositoryInterface {
private final Integer insertValue = 1000000;
private HashMap<String, BaseUnit> unitMap = new HashMap<>();
@Inject
public ListRepository() {}
public PublishSubject<BaseUnit> exec(int inputNumber) {
PublishSubject<BaseUnit> subject = PublishSubject.create();
Observable<BaseUnit> observable = getListObservable(inputNumber)
.subscribeOn(Schedulers.computation())
.flatMap(resultList ->
Observable.fromIterable(resultList)
.flatMap(listElem ->
Observable.fromArray(ListOperationName.values())
.map(operationElem -> {
ListUnit unit = new ListUnit(operationElem, listElem, 0);
calculate(unit, listElem);
unitMap.put(unit.getViewId(), unit);
return unit;
})
)
);
observable.subscribe(subject);
return subject;
}
private Observable<ArrayList<List<Integer>>> getListObservable(int inputNumber) {
return Observable.fromCallable(() -> {
ArrayList<List<Integer>> list = new ArrayList<>();
Integer[] populatedArray = new Integer[inputNumber];
Arrays.fill(populatedArray, insertValue);
list.add(new ArrayList<>(Arrays.asList(populatedArray)));
list.add(new LinkedList<>(Arrays.asList(populatedArray)));
list.add(new CopyOnWriteArrayList<>(Arrays.asList(populatedArray)));
return list;
});
}
private void calculate(ListUnit unit, List<Integer> list) {
try {
TimeUnit.MILLISECONDS.sleep(50);
} catch (InterruptedException e) {
e.printStackTrace();
}
double start = getTime();
//noinspection SynchronizationOnLocalVariableOrMethodParameter
synchronized (list) {
switch (unit.getOperationName()) {
case ADD_FIRST:
list.add(0, insertValue);
break;
case ADD_MID:
list.add(list.size() / 2, insertValue);
break;
case ADD_LAST:
list.add(insertValue);
break;
case SEARCH:
//noinspection unused
boolean contains = list.contains(insertValue);
break;
case RM_FIRST:
list.remove(0);
break;
case RM_MID:
list.remove(list.size() / 2);
break;
case RM_LAST:
list.remove(list.size() - 1);
break;
}
}
unit.setTime(getTime() - start);
}
private double getTime() {
return System.nanoTime();
}
public HashMap<String, BaseUnit> getUnitMap() {
return unitMap;
}
}
如果我删除
.subscribeOn(Schedulers.newThread())
在您最近的示例中,通过calculate(…)
方法,并对exec(…)
进行以下更改,我似乎获得了所需的并行性
public Observable<String> exec( int inputNumber )
{
return getListObservable( inputNumber )
.flatMap( resultList -> getOperationsObservable()
.flatMap( operationElem -> getResultListObservable( resultList )
.flatMap( listElem -> Observable.just( listElem )
.subscribeOn( Schedulers.computation() )
.flatMap( __ -> calculate( operationElem, listElem )))));
}
public observeable exec(int-inputNumber)
{
返回getListObservable(inputNumber)
.flatMap(结果列表->getOperationsObservable()
.flatMap(operationElem->getResultListObservable(结果列表)
.flatMap(listElem->Observable.just(listElem)
.subscribeOn(Schedulers.computation())
.flatMap(_uu->calculate(operationElem,listElem '));
}
我删除了
PublishSubject
-这似乎是多余的,您可以订阅生成的Observable
,否?为了实现与flatMap(…)
的并行性,您必须创建一个嵌套Observable
和一个嵌套的subscribeOn(…)
。示例:observable.flatMap(element->observable.just(element).subscribeOn(Schedulers.computation()).map(…)
@TrogDor我面临的问题是显示的结果取决于可观察的源大小。例如,如果flatMap源大小为3或5,则单元格将一次填充3-5个片段。但是,如果我们有8个内核,那么最好全部使用它们-如何做到这一点?一般来说,是的,计算调度程序将由一个大小等于可用内核数量的线程池支持。如果您创建了一个没有Android依赖项的普通RxJava示例,我可以看一看。@TrogDor我在post的UPD中添加了一个没有依赖项的示例,请看一下哪里出了问题。
private void run() {
Log.d("APP", "INIT");
PublishSubject<String> subject = exec(1000000);
subject.observeOn(AndroidSchedulers.mainThread())
.subscribe(unit -> {
Log.d("STRING RESULT = ", unit);
if (subject.hasComplete()) {
//TODO: this condition should work if we use observable.subscribe(subject), not subject.onNext
Log.d("SUBJECT", "COMPLETED");
}
}, Throwable::printStackTrace);
}
private int insertValue = 1000000;
public PublishSubject<String> exec(int inputNumber) {
PublishSubject<String> subject = PublishSubject.create();
getListObservable(inputNumber)
.flatMap(resultList -> getOperationsObservable()
.flatMap(operationElem -> getResultListObservable(resultList)
.map(listElem ->
calculate(operationElem, listElem)
//TODO: should be smth like this, i.e. calculate.subscribe(subject)
// .subscribe(subject)
.subscribe(subject::onNext)
)
)
).subscribe();
return subject;
}
private Observable<ArrayList<List<Integer>>> getListObservable(int inputNumber) {
return Observable.fromCallable(() -> {
ArrayList<List<Integer>> list = new ArrayList<>();
Integer[] populatedArray = new Integer[inputNumber];
Arrays.fill(populatedArray, insertValue);
list.add(new ArrayList<>(Arrays.asList(populatedArray)));
list.add(new LinkedList<>(Arrays.asList(populatedArray)));
list.add(new CopyOnWriteArrayList<>(Arrays.asList(populatedArray)));
return list;
}).subscribeOn(Schedulers.computation());
}
private Observable<String> calculate(ListOperationName operationName, List<Integer> list) {
return Observable.fromCallable(() -> {
try {
TimeUnit.MILLISECONDS.sleep(100);
} catch (InterruptedException e) {
e.printStackTrace();
}
double start = getTime();
synchronized (list) {
switch (operationName) {
case ADD_FIRST:
list.add(0, insertValue);
break;
case ADD_MID:
list.add(list.size() / 2, insertValue);
break;
case ADD_LAST:
list.add(insertValue);
break;
case SEARCH:
//noinspection unused
boolean contains = list.contains(insertValue);
break;
case RM_FIRST:
list.remove(0);
break;
case RM_MID:
list.remove(list.size() / 2);
break;
case RM_LAST:
list.remove(list.size() - 1);
break;
}
}
return Double.toString(getTime() - start);
}).subscribeOn(Schedulers.newThread());
}
private Observable<ListOperationName> getOperationsObservable() {
return Observable.fromArray(ListOperationName.values());
}
private Observable<List<Integer>> getResultListObservable(ArrayList<List<Integer>> list) {
return Observable.fromIterable(list);
}
private double getTime() {
return System.nanoTime();
}
public enum ListOperationName {
ADD_FIRST,
ADD_MID,
ADD_LAST,
SEARCH,
RM_FIRST,
RM_MID,
RM_LAST;
}
dependencies {
implementation 'io.reactivex.rxjava3:rxandroid:3.0.0'
implementation 'io.reactivex.rxjava3:rxjava:3.0.4'
}
public Observable<String> exec( int inputNumber )
{
return getListObservable( inputNumber )
.flatMap( resultList -> getOperationsObservable()
.flatMap( operationElem -> getResultListObservable( resultList )
.flatMap( listElem -> Observable.just( listElem )
.subscribeOn( Schedulers.computation() )
.flatMap( __ -> calculate( operationElem, listElem )))));
}