+++ /dev/null
-package org.argeo.util.register;
-
-import java.util.ArrayList;
-import java.util.Collections;
-import java.util.HashMap;
-import java.util.HashSet;
-import java.util.List;
-import java.util.Map;
-import java.util.Set;
-import java.util.concurrent.CompletableFuture;
-import java.util.concurrent.CompletionStage;
-import java.util.function.Consumer;
-import java.util.function.Supplier;
-
-/**
- * A wrapper for an object, whose dependencies and life cycle can be managed.
- */
-public class Component<I> implements Supplier<I>, Comparable<Component<?>> {
-
- private final I instance;
-
- private final Runnable init;
- private final Runnable close;
-
- private final Map<Class<? super I>, PublishedType<? super I>> types;
- private final Set<Dependency<?>> dependencies;
- private final Map<String, Object> properties;
-
- private CompletableFuture<Void> activationStarted = null;
- private CompletableFuture<Void> activated = null;
-
- private CompletableFuture<Void> deactivationStarted = null;
- private CompletableFuture<Void> deactivated = null;
-
- // internal
- private Set<Dependency<?>> dependants = new HashSet<>();
-
- private RankingKey rankingKey;
-
- Component(ComponentRegister register, I instance, Runnable init, Runnable close, Set<Dependency<?>> dependencies,
- Set<Class<? super I>> classes, Map<String, Object> properties) {
- assert instance != null;
- assert init != null;
- assert close != null;
- assert dependencies != null;
- assert classes != null;
-
- this.instance = instance;
- this.init = init;
- this.close = close;
-
- // types
- Map<Class<? super I>, PublishedType<? super I>> types = new HashMap<>(classes.size());
- for (Class<? super I> clss : classes) {
-// if (!clss.isAssignableFrom(instance.getClass()))
-// throw new IllegalArgumentException(
-// "Type " + clss.getName() + " is not compatible with " + instance.getClass().getName());
- types.put(clss, new PublishedType<>(this, clss));
- }
- this.types = Collections.unmodifiableMap(types);
-
- // dependencies
- this.dependencies = Collections.unmodifiableSet(new HashSet<>(dependencies));
- for (Dependency<?> dependency : this.dependencies) {
- dependency.setDependantComponent(this);
- }
-
- // deactivated by default
- deactivated = CompletableFuture.completedFuture(null);
- deactivationStarted = CompletableFuture.completedFuture(null);
-
- // TODO check whether context is active, so that we start right away
- prepareNextActivation();
-
- long serviceId = register.register(this);
- Map<String, Object> props = new HashMap<>(properties);
- props.put(RankingKey.SERVICE_ID, serviceId);
- this.properties = Collections.unmodifiableMap(props);
- rankingKey = new RankingKey(properties);
- }
-
- private void prepareNextActivation() {
- activationStarted = new CompletableFuture<Void>();
- activated = activationStarted //
- .thenComposeAsync(this::dependenciesActivated) //
- .thenRun(this.init) //
- .thenRun(() -> prepareNextDeactivation());
- }
-
- private void prepareNextDeactivation() {
- deactivationStarted = new CompletableFuture<Void>();
- deactivated = deactivationStarted //
- .thenComposeAsync(this::dependantsDeactivated) //
- .thenRun(this.close) //
- .thenRun(() -> prepareNextActivation());
- }
-
- CompletableFuture<Void> getActivated() {
- return activated;
- }
-
- CompletableFuture<Void> getDeactivated() {
- return deactivated;
- }
-
- void startActivating() {
- if (activated.isDone() || activationStarted.isDone())
- return;
- activationStarted.complete(null);
- }
-
- void startDeactivating() {
- if (deactivated.isDone() || deactivationStarted.isDone())
- return;
- deactivationStarted.complete(null);
- }
-
- CompletableFuture<Void> dependenciesActivated(Void v) {
- Set<CompletableFuture<?>> constraints = new HashSet<>(this.dependencies.size());
- for (Dependency<?> dependency : this.dependencies) {
- CompletableFuture<Void> dependencyActivated = dependency.publisherActivated() //
- .thenCompose(dependency::set);
- constraints.add(dependencyActivated);
- }
- return CompletableFuture.allOf(constraints.toArray(new CompletableFuture[constraints.size()]));
- }
-
- CompletableFuture<Void> dependantsDeactivated(Void v) {
- Set<CompletableFuture<?>> constraints = new HashSet<>(this.dependants.size());
- for (Dependency<?> dependant : this.dependants) {
- CompletableFuture<Void> dependantDeactivated = dependant.dependantDeactivated() //
- .thenCompose(dependant::unset);
- constraints.add(dependantDeactivated);
- }
- CompletableFuture<Void> dependantsDeactivated = CompletableFuture
- .allOf(constraints.toArray(new CompletableFuture[constraints.size()]));
- return dependantsDeactivated;
-
- }
-
- void addDependant(Dependency<?> dependant) {
- dependants.add(dependant);
- }
-
- @Override
- public I get() {
- return instance;
- }
-
- @SuppressWarnings("unchecked")
- public <T> PublishedType<T> getType(Class<T> clss) {
- if (!types.containsKey(clss))
- throw new IllegalArgumentException(clss.getName() + " is not a type published by this component");
- return (PublishedType<T>) types.get(clss);
- }
-
- public <T> boolean isPublishedType(Class<T> clss) {
- return types.containsKey(clss);
- }
-
- public Map<String, Object> getProperties() {
- return properties;
- }
-
- @Override
- public int compareTo(Component<?> o) {
- return rankingKey.compareTo(rankingKey);
- }
-
- @Override
- public int hashCode() {
- Long serviceId = (Long) properties.get(RankingKey.SERVICE_ID);
- if (serviceId != null)
- return serviceId.intValue();
- else
- return super.hashCode();
- }
-
- @Override
- public String toString() {
- List<String> classes = new ArrayList<>();
- for (Class<?> clss : types.keySet()) {
- classes.add(clss.getName());
- }
- return "Component " + classes + " " + properties + "";
- }
-
- /** A type which has been explicitly exposed by a component. */
- public static class PublishedType<T> {
- private Component<? extends T> component;
- private Class<T> clss;
-
- private CompletableFuture<T> value;
-
- public PublishedType(Component<? extends T> component, Class<T> clss) {
- this.clss = clss;
- this.component = component;
- value = CompletableFuture.completedFuture((T) component.instance);
- }
-
- public Component<?> getPublisher() {
- return component;
- }
-
- public Class<T> getType() {
- return clss;
- }
-
- public CompletionStage<T> getValue() {
- return value.minimalCompletionStage();
- }
- }
-
- /** Builds a {@link Component}. */
- public static class Builder<I> implements Supplier<I> {
- private final I instance;
-
- private Runnable init;
- private Runnable close;
-
- private Set<Dependency<?>> dependencies = new HashSet<>();
- private Set<Class<? super I>> types = new HashSet<>();
- private final Map<String, Object> properties = new HashMap<>();
-
- public Builder(I instance) {
- this.instance = instance;
- }
-
- public Component<I> build(ComponentRegister register) {
- // default values
- if (types.isEmpty()) {
- types.add(getInstanceClass());
- }
-
- if (init == null)
- init = () -> {
- };
- if (close == null)
- close = () -> {
- };
-
- // instantiation
- Component<I> component = new Component<I>(register, instance, init, close, dependencies, types, properties);
- for (Dependency<?> dependency : dependencies) {
- dependency.type.getPublisher().addDependant(dependency);
- }
- return component;
- }
-
- public Builder<I> addType(Class<? super I> clss) {
- types.add(clss);
- return this;
- }
-
- public Builder<I> addActivation(Runnable init) {
- if (this.init != null)
- throw new IllegalArgumentException("init method is already set");
- this.init = init;
- return this;
- }
-
- public Builder<I> addDeactivation(Runnable close) {
- if (this.close != null)
- throw new IllegalArgumentException("close method is already set");
- this.close = close;
- return this;
- }
-
- public <D> Builder<I> addDependency(PublishedType<D> type, Consumer<D> set, Consumer<D> unset) {
- dependencies.add(new Dependency<D>(type, set, unset));
- return this;
- }
-
- public void addProperty(String key, Object value) {
- if (properties.containsKey(key))
- throw new IllegalStateException("Key " + key + " is already set.");
- properties.put(key, value);
- }
-
- @Override
- public I get() {
- return instance;
- }
-
- @SuppressWarnings("unchecked")
- private Class<I> getInstanceClass() {
- return (Class<I>) instance.getClass();
- }
-
- }
-
- static class Dependency<D> {
- private PublishedType<D> type;
- private Consumer<D> set;
- private Consumer<D> unset;
-
- // live
- Component<?> dependantComponent;
- CompletableFuture<Void> setStage;
- CompletableFuture<Void> unsetStage;
-
- public Dependency(PublishedType<D> types, Consumer<D> set, Consumer<D> unset) {
- super();
- this.type = types;
- this.set = set != null ? set : t -> {
- };
- this.unset = unset != null ? unset : t -> {
- };
- }
-
- // live
- void setDependantComponent(Component<?> component) {
- this.dependantComponent = component;
- }
-
- CompletableFuture<Void> publisherActivated() {
- return type.getPublisher().activated.copy();
- }
-
- CompletableFuture<Void> dependantDeactivated() {
- return dependantComponent.deactivated.copy();
- }
-
- CompletableFuture<Void> set(Void v) {
- return type.value.thenAccept(set);
- }
-
- CompletableFuture<Void> unset(Void v) {
- return type.value.thenAccept(unset);
- }
-
- }
-}
projects / lgpl / argeo-commons.git / blobdiff