package org.infinispan.interceptors;
import java.util.concurrent.CompletableFuture;
import org.infinispan.commands.VisitableCommand;
import org.infinispan.commons.util.Experimental;
import org.infinispan.configuration.cache.Configuration;
import org.infinispan.context.InvocationContext;
import org.infinispan.factories.annotations.Inject;
import org.infinispan.interceptors.impl.SimpleAsyncInvocationStage;
/**
* Base class for an interceptor in the new asynchronous invocation chain.
*
* @author Dan Berindei
* @since 9.0
*/
@Experimental
public abstract class BaseAsyncInterceptor implements AsyncInterceptor {
private final InvocationSuccessFunction invokeNextFunction = (rCtx, rCommand, rv) -> invokeNext(rCtx, rCommand);
protected Configuration cacheConfiguration;
private AsyncInterceptor nextInterceptor;
private DDAsyncInterceptor nextDDInterceptor;
@Inject
public void inject(Configuration cacheConfiguration) {
this.cacheConfiguration = cacheConfiguration;
}
/**
* Used internally to set up the interceptor.
*/
@Override
public final void setNextInterceptor(AsyncInterceptor nextInterceptor) {
this.nextInterceptor = nextInterceptor;
this.nextDDInterceptor =
nextInterceptor instanceof DDAsyncInterceptor ? (DDAsyncInterceptor) nextInterceptor : null;
}
/**
* Invoke the next interceptor, possibly with a new command.
*
* <p>Use {@link #invokeNextThenApply(InvocationContext, VisitableCommand, InvocationSuccessFunction)}
* or {@link #invokeNextThenAccept(InvocationContext, VisitableCommand, InvocationSuccessAction)} instead
* if you need to process the return value of the next interceptor.</p>
*
* <p>Note: {@code invokeNext(ctx, command)} does not throw exceptions. In order to handle exceptions from the
* next interceptors, you <em>must</em> use
* {@link #invokeNextAndHandle(InvocationContext, VisitableCommand, InvocationFinallyFunction)},
* {@link #invokeNextAndFinally(InvocationContext, VisitableCommand, InvocationFinallyAction)},
* or {@link #invokeNextAndExceptionally(InvocationContext, VisitableCommand, InvocationExceptionFunction)}.</p>
*/
public final Object invokeNext(InvocationContext ctx, VisitableCommand command) {
try {
if (nextDDInterceptor != null) {
return command.acceptVisitor(ctx, nextDDInterceptor);
} else {
return nextInterceptor.visitCommand(ctx, command);
}
} catch (Throwable throwable) {
return new SimpleAsyncInvocationStage(throwable);
}
}
/**
* Invoke the next interceptor, possibly with a new command, and execute an {@link InvocationCallback}
* after all the interceptors have finished successfully.
*
* <p>You need to wrap the result with {@link #makeStage(Object)} if you need to add another handler.</p>
*/
public final Object invokeNextThenApply(InvocationContext ctx, VisitableCommand command,
InvocationSuccessFunction function) {
try {
Object rv;
if (nextDDInterceptor != null) {
rv = command.acceptVisitor(ctx, nextDDInterceptor);
} else {
rv = nextInterceptor.visitCommand(ctx, command);
}
if (rv instanceof InvocationStage) {
return ((InvocationStage) rv).thenApply(ctx, command, function);
}
return function.apply(ctx, command, rv);
} catch (Throwable throwable) {
return new SimpleAsyncInvocationStage(throwable);
}
}
/**
* Invoke the next interceptor, possibly with a new command, and execute an {@link InvocationCallback}
* after all the interceptors have finished successfully.
*
* <p>You need to wrap the result with {@link #makeStage(Object)} if you need to add another handler.</p>
*/
public final Object invokeNextThenAccept(InvocationContext ctx, VisitableCommand command,
InvocationSuccessAction action) {
try {
Object rv;
if (nextDDInterceptor != null) {
rv = command.acceptVisitor(ctx, nextDDInterceptor);
} else {
rv = nextInterceptor.visitCommand(ctx, command);
}
if (rv instanceof InvocationStage) {
return ((InvocationStage) rv).thenAccept(ctx, command, action);
}
action.accept(ctx, command, rv);
return rv;
} catch (Throwable throwable) {
return new SimpleAsyncInvocationStage(throwable);
}
}
/**
* Invoke the next interceptor, possibly with a new command, and execute an {@link InvocationCallback}
* after all the interceptors have finished with an exception.
*
* <p>You need to wrap the result with {@link #makeStage(Object)} if you need to add another handler.</p>
*/
public final Object invokeNextAndExceptionally(InvocationContext ctx, VisitableCommand command,
InvocationExceptionFunction function) {
try {
Object rv;
if (nextDDInterceptor != null) {
rv = command.acceptVisitor(ctx, nextDDInterceptor);
} else {
rv = nextInterceptor.visitCommand(ctx, command);
}
if (rv instanceof InvocationStage) {
return ((InvocationStage) rv).andExceptionally(ctx, command, function);
}
// No exception
return rv;
} catch (Throwable throwable) {
return new SimpleAsyncInvocationStage(throwable);
}
}
/**
* Invoke the next interceptor, possibly with a new command, and execute an {@link InvocationCallback}
* after all the interceptors have finished, with or without an exception.
*
* <p>You need to wrap the result with {@link #makeStage(Object)} if you need to add another handler.</p>
*/
public final Object invokeNextAndFinally(InvocationContext ctx, VisitableCommand command,
InvocationFinallyAction action) {
try {
Object rv;
Throwable throwable;
try {
if (nextDDInterceptor != null) {
rv = command.acceptVisitor(ctx, nextDDInterceptor);
} else {
rv = nextInterceptor.visitCommand(ctx, command);
}
throwable = null;
if (rv instanceof InvocationStage) {
return ((InvocationStage) rv).andFinally(ctx, command, action);
}
} catch (Throwable t) {
rv = null;
throwable = t;
}
action.accept(ctx, command, rv, throwable);
return throwable == null ? rv : new SimpleAsyncInvocationStage(throwable);
} catch (Throwable t) {
return new SimpleAsyncInvocationStage(t);
}
}
/**
* Invoke the next interceptor, possibly with a new command, and execute an {@link InvocationCallback}
* after all the interceptors have finished, with or without an exception.
*
* <p>You need to wrap the result with {@link #makeStage(Object)} if you need to add another handler.</p>
*/
public final Object invokeNextAndHandle(InvocationContext ctx, VisitableCommand command,
InvocationFinallyFunction function) {
try {
Object rv;
Throwable throwable;
try {
if (nextDDInterceptor != null) {
rv = command.acceptVisitor(ctx, nextDDInterceptor);
} else {
rv = nextInterceptor.visitCommand(ctx, command);
}
throwable = null;
if (rv instanceof InvocationStage) {
return ((InvocationStage) rv).andHandle(ctx, command, function);
}
} catch (Throwable t) {
rv = null;
throwable = t;
}
return function.apply(ctx, command, rv, throwable);
} catch (Throwable throwable) {
return new SimpleAsyncInvocationStage(throwable);
}
}
/**
* Suspend the invocation until {@code valueFuture} completes, then return its result without running
* the remaining interceptors.
*
* <p>The caller can add a callback that will run when {@code valueFuture} completes, e.g.
* {@code asyncValue(v).thenApply(ctx, command, (rCtx, rCommand, rv, t) -> invokeNext(rCtx, rCommand))}.
* For this particular scenario, however, it's simpler to use
* {@link #asyncInvokeNext(InvocationContext, VisitableCommand, CompletableFuture)}.</p>
*/
public static InvocationStage asyncValue(CompletableFuture<?> valueFuture) {
return new SimpleAsyncInvocationStage(valueFuture);
}
/**
* Suspend the invocation until {@code delay} completes, then if successful invoke the next interceptor.
*
* <p>If {@code delay} completes exceptionally, skip the next interceptor and continue with the exception.</p>
*
* <p>You need to wrap the result with {@link #makeStage(Object)} if you need to add another handler.</p>
*/
public final Object asyncInvokeNext(InvocationContext ctx, VisitableCommand command,
CompletableFuture<?> delay) {
return asyncValue(delay).thenApply(ctx, command, invokeNextFunction);
}
/**
* Return the value if {@code throwable != null}, throw the exception otherwise.
*/
public static Object valueOrException(Object rv, Throwable throwable) throws Throwable {
if (throwable == null) {
return rv;
} else {
throw throwable;
}
}
/**
* Encode the result of an {@link #invokeNext(InvocationContext, VisitableCommand)} in an {@link InvocationStage}.
*
* <p>May not create a new instance, if the result is already an {@code InvocationStage}.
*/
public static InvocationStage makeStage(Object rv) {
if (rv instanceof InvocationStage) {
return (InvocationStage) rv;
} else {
return new SyncInvocationStage(rv);
}
}
}