ServiceLoader-based Discoverer

pom.xml

@@ -47,12 +47,13 @@
 	<modules>
 		<module>imagej/imagej-ops2</module>
 		<module>imagej/imagej-testutil</module>
-		<module>scijava/scijava-persist</module>
+		<module>scijava/scijava-discovery</module>
 		<module>scijava/scijava-function</module>
 		<module>scijava/scijava-ops-api</module>
-		<module>scijava/scijava-ops-discovery</module>
 		<module>scijava/scijava-ops-engine</module>
+		<module>scijava/scijava-ops-serviceloader</module>
 		<module>scijava/scijava-ops-spi</module>
+		<module>scijava/scijava-persist</module>
 		<module>scijava/scijava-struct</module>
 		<module>scijava/scijava-taglets</module>
 		<module>scijava/scijava-testutil</module>

scijava/scijava-discovery/.gitignore

@@ -0,0 +1,2 @@
+/.apt_generated/
+/.apt_generated_tests/

scijava/scijava-ops-discovery/pom.xml → scijava/scijava-discovery/pom.xml

@@ -11,11 +11,11 @@
 		<relativePath>../..</relativePath>
 	</parent>
 
-	<artifactId>scijava-ops-discovery</artifactId>
+	<artifactId>scijava-discovery</artifactId>
 
-	<name>SciJava Ops Discovery</name>
-	<description>SciJava Operations Discovery: Discovery mechanisms used by the SciJava Operations framework.</description>
-	<url>https://github.com/scijava/scijava-ops-discovery</url>
+	<name>SciJava Discovery</name>
+	<description>SciJava Discovery: Discovery mechanisms used by the SciJava Framework.</description>
+	<url>https://github.com/scijava/scijava-discovery</url>
 	<inceptionYear>2021</inceptionYear>
 	<organization>
 		<name>SciJava</name>
@@ -78,7 +78,7 @@
 	<mailingLists>
 		<mailingList>
 			<name>Image.sc Forum</name>
-			<archive>https://forum.image.sc/tags/scijava-ops-discovery</archive>
+			<archive>https://forum.image.sc/tags/scijava-discovery</archive>
 		</mailingList>
 	</mailingLists>
 
@@ -90,22 +90,21 @@
 	</scm>
 	<issueManagement>
 		<system>GitHub Issues</system>
-		<url>https://github.com/scijava/scijava-ops-discovery/issues</url>
+		<url>https://github.com/scijava/scijava-discovery/issues</url>
 	</issueManagement>
 	<ciManagement>
 		<system>Travis CI</system>
 		<url>https://travis-ci.com/scijava/incubator</url>
 	</ciManagement>
 
 	<properties>
-		<main-class>org.scijava.ops.discovery.Main</main-class>
-		<package-name>org.scijava.ops.discovery</package-name>
+		<main-class>org.scijava.discovery.Main</main-class>
+		<package-name>org.scijava.discovery</package-name>
 
 		<license.licenseName>bsd_2</license.licenseName>
 		<license.copyrightOwners>SciJava developers.</license.copyrightOwners>
-		<!--  <enforcer.skip>true</enforcer.skip>-->
-		<scijava-ops-discovery.allowedDuplicateClasses>${scijava.allowedDuplicateClasses},com.github.therapi.runtimejavadoc.repack.com.eclipsesource.json.*</scijava-ops-discovery.allowedDuplicateClasses>
-		<allowedDuplicateClasses>${scijava-ops-discovery.allowedDuplicateClasses}</allowedDuplicateClasses>
+		<scijava-discovery.allowedDuplicateClasses>${scijava.allowedDuplicateClasses},com.github.therapi.runtimejavadoc.repack.com.eclipsesource.json.*</scijava-discovery.allowedDuplicateClasses>
+		<allowedDuplicateClasses>${scijava-discovery.allowedDuplicateClasses}</allowedDuplicateClasses>
 	</properties>
 	<dependencies>
 	</dependencies>

scijava/scijava-discovery/src/main/java/module-info.java

@@ -0,0 +1,5 @@
+module org.scijava.discovery {
+
+	exports org.scijava.discovery;
+
+}

scijava/scijava-discovery/src/main/java/org/scijava/discovery/Discoverer.java

@@ -0,0 +1,10 @@
+
+package org.scijava.discovery;
+
+import java.util.List;
+
+public interface Discoverer {
+
+	<T> List<Class<T>> implementingClasses(Class<T> c);
+
+}

scijava/scijava-ops-discovery/src/main/java/org/scijava/ops/discovery/Implementation.java → scijava/scijava-discovery/src/main/java/org/scijava/discovery/Implementation.java

@@ -1,4 +1,4 @@
-package org.scijava.ops.discovery;
+package org.scijava.discovery;
 
 import java.lang.reflect.Type;
 

scijava/scijava-discovery/src/main/java/org/scijava/discovery/StaticDiscoverer.java

@@ -0,0 +1,30 @@
+
+package org.scijava.discovery;
+
+import java.util.HashMap;
+import java.util.List;
+import java.util.Map;
+import java.util.stream.Collectors;
+
+public class StaticDiscoverer implements Discoverer {
+
+	Map<Class<?>, String> names;
+
+	public StaticDiscoverer() {
+		names = new HashMap<>();
+	}
+
+	public void register(Class<?> c, String name) {
+		names.put(c, name);
+	}
+
+	@SuppressWarnings("unchecked")
+	@Override
+	public <T> List<Class<T>> implementingClasses(Class<T> c) {
+		return names.keySet().stream() //
+			.filter(cls -> cls.isAssignableFrom(c)) //
+			.map(cls -> (Class<T>) cls) //
+			.collect(Collectors.toList());
+	}
+
+}

scijava/scijava-ops-discovery/.gitignore

@@ -1,2 +1 @@
-/.apt_generated/
-/.apt_generated_tests/
+/bin/

scijava/scijava-ops-engine/pom.xml

@@ -133,7 +133,12 @@
 		</dependency>
 		<dependency>
 			<groupId>org.scijava</groupId>
-			<artifactId>scijava-ops-discovery</artifactId>
+			<artifactId>scijava-discovery</artifactId>
+			<version>${project.version}</version>
+		</dependency>
+		<dependency>
+			<groupId>org.scijava</groupId>
+			<artifactId>scijava-ops-serviceloader</artifactId>
 			<version>${project.version}</version>
 		</dependency>
 		<dependency>

scijava/scijava-ops-engine/src/main/java/module-info.java

@@ -34,15 +34,18 @@
 	requires java.desktop;
 
 	requires org.scijava;
+	requires org.scijava.discovery;
 	requires org.scijava.function;
 	requires org.scijava.struct;
 	requires org.scijava.ops.api;
-	requires org.scijava.ops.discovery;
+	requires org.scijava.ops.serviceloader;
 	requires org.scijava.ops.spi;
 	requires org.scijava.types;
 	requires javassist;
 	requires java.compiler;
 	requires therapi.runtime.javadoc;
 
 	uses javax.annotation.processing.Processor;
+	provides org.scijava.ops.spi.OpCollection with org.scijava.ops.engine.copy.CopyOpCollection;
+	provides org.scijava.ops.spi.Op with org.scijava.ops.engine.stats.Mean.MeanFunction;
 }

scijava/scijava-ops-engine/src/main/java/org/scijava/ops/engine/copy/CopyOpCollection.java

@@ -4,10 +4,8 @@
 import org.scijava.function.Computers;
 import org.scijava.ops.spi.OpCollection;
 import org.scijava.ops.spi.OpField;
-import org.scijava.plugin.Plugin;
 
-@Plugin(type = OpCollection.class)
-public class CopyOpCollection <T>{
+public class CopyOpCollection <T> implements OpCollection{
 
 	@OpField(names = "cp, copy", priority = Priority.LOW, params = "array, arrayCopy")
 	public static final Computers.Arity1<double[], double[]> copyPrimitiveDoubleArray = (from, to) -> {

scijava/scijava-ops-engine/src/main/java/org/scijava/ops/engine/impl/DefaultOpEnvironment.java

@@ -47,6 +47,7 @@
 import java.util.stream.Collectors;
 
 import org.scijava.Priority;
+import org.scijava.discovery.Discoverer;
 import org.scijava.log.LogService;
 import org.scijava.ops.api.Hints;
 import org.scijava.ops.api.OpCandidate;
@@ -57,7 +58,6 @@
 import org.scijava.ops.api.OpInfoGenerator;
 import org.scijava.ops.api.OpRef;
 import org.scijava.ops.api.OpWrapper;
-import org.scijava.ops.discovery.Discoverer;
 import org.scijava.ops.engine.BaseOpHints.Adaptation;
 import org.scijava.ops.engine.BaseOpHints.DependencyMatching;
 import org.scijava.ops.engine.BaseOpHints.Simplification;
@@ -92,7 +92,7 @@
  */
 public class DefaultOpEnvironment implements OpEnvironment {
 
-	private final Discoverer discoverer;
+	private final List<Discoverer> discoverers;
 
 	private OpMatcher matcher;
 
@@ -137,8 +137,17 @@ public class DefaultOpEnvironment implements OpEnvironment {
 	 */
 	private Hints environmentHints = null;
 
-	public DefaultOpEnvironment(final Discoverer d, final TypeService typeService, final LogService log, final OpHistoryService history, final List<OpInfoGenerator> infoGenerators) {
-		this.discoverer = d;
+	public DefaultOpEnvironment(final TypeService typeService, final LogService log, final OpHistoryService history, final List<OpInfoGenerator> infoGenerators, final List<Discoverer> d) {
+		this.discoverers = d;
+		this.typeService = typeService;
+		this.log = log;
+		this.history = history;
+		this.infoGenerators = infoGenerators;
+		matcher = new DefaultOpMatcher();
+	}
+
+	public DefaultOpEnvironment(final TypeService typeService, final LogService log, final OpHistoryService  history, final List<OpInfoGenerator> infoGenerators, final Discoverer... d) {
+		this.discoverers = Arrays.asList(d);
 		this.typeService = typeService;
 		this.log = log;
 		this.history = history;
@@ -486,11 +495,19 @@ private List<MatchingConditions> resolveOpDependencies(OpCandidate candidate, Hi
 
 	private void initWrappers() {
 		wrappers = new HashMap<>();
-		Class<?>[] constructorClasses = {};
-		Object[] constructorObjects = {};
-		for (OpWrapper<?> wrapper : discoverer.implementingInstances(OpWrapper.class, constructorClasses, constructorObjects)) {
-			wrappers.put(wrapper.type(), wrapper);
-		}
+		for (Discoverer d : discoverers)
+			for (Class<OpWrapper> cls : d.implementingClasses(OpWrapper.class))
+			{
+				OpWrapper<?> wrapper;
+				try {
+					wrapper = cls.getDeclaredConstructor().newInstance();
+					wrappers.put(wrapper.type(), wrapper);
+				}
+				catch (Throwable t)
+				{
+					log.warn("OpWrapper " + cls + " not instantiated. Due to " + t);
+				}
+			}
 	}
 
 	/**