[build] sped up the build considerable.

We used to use the mango SPI processor, but this had two major issues:
* ecj wouldn't run annotation processors, requiring a separate proc:only compile run with javac
* mangoSPI couldn't do incremental compilation, so this required a full rebuild just to generate SPI files, every time.

Addressed by updating to IPP40 which does support explicit annotation processors even for ecj, and
adding our own SPI generating annotation processor to the build which can deal with incrementals.

There are some limits; removing a `@Provides` annotation on an existing type will need a full clean to pick that up, for example.
These limits seem quite exotic, though.

5 files changed, 625 insertions, 0 deletions

diff --git a/src/spiProcessor/lombok/spi/Provides.java b/src/spiProcessor/lombok/spi/Provides.java
new file mode 100644
index 00000000..de930819
--- /dev/null
+++ b/src/spiProcessor/lombok/spi/Provides.java
@@ -0,0 +1,33 @@
+/*
+ * Copyright (C) 2021 The Project Lombok Authors.
+ * 
+ * Permission is hereby granted, free of charge, to any person obtaining a copy
+ * of this software and associated documentation files (the "Software"), to deal
+ * in the Software without restriction, including without limitation the rights
+ * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+ * copies of the Software, and to permit persons to whom the Software is
+ * furnished to do so, subject to the following conditions:
+ * 
+ * The above copyright notice and this permission notice shall be included in
+ * all copies or substantial portions of the Software.
+ * 
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+ * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+ * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+ * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+ * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+ * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
+ * THE SOFTWARE.
+ */
+package lombok.spi;
+
+import java.lang.annotation.ElementType;
+import java.lang.annotation.Retention;
+import java.lang.annotation.RetentionPolicy;
+import java.lang.annotation.Target;
+
+@Target(ElementType.TYPE)
+@Retention(RetentionPolicy.SOURCE)
+public @interface Provides {
+	Class<?>[] value() default {};
+}
diff --git a/src/spiProcessor/lombok/spi/SpiProcessor.java b/src/spiProcessor/lombok/spi/SpiProcessor.java
new file mode 100644
index 00000000..975a85c7
--- /dev/null
+++ b/src/spiProcessor/lombok/spi/SpiProcessor.java
@@ -0,0 +1,254 @@
+/*
+ * Copyright (C) 2021 The Project Lombok Authors.
+ * 
+ * Permission is hereby granted, free of charge, to any person obtaining a copy
+ * of this software and associated documentation files (the "Software"), to deal
+ * in the Software without restriction, including without limitation the rights
+ * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+ * copies of the Software, and to permit persons to whom the Software is
+ * furnished to do so, subject to the following conditions:
+ * 
+ * The above copyright notice and this permission notice shall be included in
+ * all copies or substantial portions of the Software.
+ * 
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+ * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+ * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+ * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+ * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+ * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
+ * THE SOFTWARE.
+ */
+package lombok.spi;
+
+import java.io.IOException;
+import java.util.ArrayDeque;
+import java.util.ArrayList;
+import java.util.Deque;
+import java.util.List;
+import java.util.Map.Entry;
+import java.util.Set;
+
+import javax.annotation.processing.AbstractProcessor;
+import javax.annotation.processing.ProcessingEnvironment;
+import javax.annotation.processing.RoundEnvironment;
+import javax.annotation.processing.SupportedAnnotationTypes;
+import javax.lang.model.SourceVersion;
+import javax.lang.model.element.AnnotationMirror;
+import javax.lang.model.element.AnnotationValue;
+import javax.lang.model.element.Element;
+import javax.lang.model.element.ElementKind;
+import javax.lang.model.element.ExecutableElement;
+import javax.lang.model.element.Modifier;
+import javax.lang.model.element.Name;
+import javax.lang.model.element.TypeElement;
+import javax.lang.model.type.DeclaredType;
+import javax.lang.model.type.TypeMirror;
+
+import javax.tools.Diagnostic.Kind;
+
+@SupportedAnnotationTypes("*")
+public class SpiProcessor extends AbstractProcessor {
+	private SpiProcessorCollector data;
+	private SpiProcessorPersistence persistence;
+	
+	static String getRootPathOfServiceFiles() {
+		return "META-INF/services/";
+	}
+	
+	@Override public SourceVersion getSupportedSourceVersion() {
+		return SourceVersion.latest();
+	}
+	
+	static String toErrorMsg(Exception e, String pathName) {
+		StringBuilder sb = new StringBuilder();
+		sb.append("Exception applying SPI processor on ").append(pathName).append(": ").append(toStringLong(e));
+		return sb.toString();
+	}
+	
+	private static String toStringLong(Throwable t) {
+		if (t == null) return "NULL";
+		StringBuilder out = new StringBuilder();
+		
+		String msg = t.getMessage();
+		out.append(t.getClass().getName());
+		if (msg != null) out.append(": ").append(msg);
+		String indent = "  ";
+		
+		StackTraceElement[] elems = t.getStackTrace();
+		if (elems != null) for (int i = 0; i < elems.length; i++) {
+			out.append("\n").append(indent).append(elems[i]);
+		}
+		Throwable cause = t.getCause();
+		while (cause != null) {
+			indent = indent + " ";
+			out.append("\n").append(indent).append("Caused by: ").append(cause.getClass().getName());
+			msg = cause.getMessage();
+			if (msg != null) out.append(": ").append(msg);
+			elems = cause.getStackTrace();
+			indent = indent + " ";
+			if (elems != null) for (int i = 0; i < elems.length; i++) {
+				out.append("\n").append(indent).append(elems[i]);
+			}
+			cause = cause.getCause();
+		}
+		return out.toString();
+	}
+	
+	@Override public synchronized void init(ProcessingEnvironment processingEnv) {
+		super.init(processingEnv);
+		persistence = new SpiProcessorPersistence("SpiProcessor", processingEnv.getFiler(), processingEnv.getMessager());
+		data = new SpiProcessorCollector(processingEnv);
+		for (String serviceName : persistence.tryFind()) data.getService(serviceName);
+		data.stripProvidersWithoutSourceFile();
+	}
+	
+	@Override public boolean process(Set<? extends TypeElement> annotations, RoundEnvironment roundEnv) {
+		removeStaleData(roundEnv);
+		handleAnnotations(roundEnv);
+		if (roundEnv.processingOver()) writeData();
+		
+		return false;
+	}
+	
+	private void writeData() {
+		for (SpiProcessorService service : data.services()) {
+			try {
+				persistence.write(service.getName(), service.toProvidersListFormat());
+			} 
+			catch (IOException e) {
+				processingEnv.getMessager().printMessage(Kind.ERROR, e.getMessage());
+			}
+		}
+	}
+	
+	private void removeStaleData(RoundEnvironment roundEnv) {
+		for (Element e : roundEnv.getRootElements()) {
+			if (e instanceof TypeElement) {
+				TypeElement currentClass = (TypeElement) e;
+				data.removeProvider(createProperQualifiedName(currentClass));
+			}
+		}
+	}
+	
+	private void handleAnnotations(RoundEnvironment roundEnv) {
+		Set<? extends Element> elements = roundEnv.getElementsAnnotatedWith(Provides.class);
+		for (Element e : elements) handleProvidingElement(e);
+	}
+	
+	private void handleProvidingElement(Element element) {
+		if (element.getKind() != ElementKind.CLASS) {
+			report(element, "is not a class definition");
+			return;
+		}
+		
+		TypeElement elem = (TypeElement) element;
+		
+		Element enclosing = elem.getEnclosingElement();
+		if (enclosing != null && enclosing.getKind() == ElementKind.CLASS && !elem.getModifiers().contains(Modifier.STATIC)) {
+			report(elem, "is a non-static inner class");
+			return;
+		}
+		
+		boolean hasConstructors = false;
+		boolean hasNoArgsConstructor = false;
+		for (Element child : elem.getEnclosedElements()) {
+			if (child.getKind() != ElementKind.CONSTRUCTOR) continue;
+			ExecutableElement ee = (ExecutableElement) child;
+			hasConstructors = true;
+			if (ee.getParameters().isEmpty()) {
+				hasNoArgsConstructor = true;
+				break;
+			}
+		}
+		
+		if (hasConstructors && !hasNoArgsConstructor) {
+			report(elem, "has no no-args constructor");
+			return;
+		}
+		
+		List<TypeMirror> spiTypes = new ArrayList<TypeMirror>();
+		
+		for (AnnotationMirror annMirror : element.getAnnotationMirrors()) {
+			if (!getQualifiedTypeName(annMirror).contentEquals(Provides.class.getName())) continue;
+			for (Entry<? extends ExecutableElement, ? extends AnnotationValue> entry : annMirror.getElementValues().entrySet()) {
+				if (!entry.getKey().getSimpleName().contentEquals("value")) continue;
+				Object list = entry.getValue().getValue();
+				if (list instanceof TypeMirror) spiTypes.add((TypeMirror) list);
+				else if (list instanceof List<?>) {
+					for (Object tm : (List<?>) list) {
+						if (tm instanceof AnnotationValue) tm = ((AnnotationValue) tm).getValue();
+						if (tm instanceof TypeMirror) {
+							TypeMirror mirror = (TypeMirror) tm;
+							mirror = processingEnv.getTypeUtils().erasure(mirror);
+							spiTypes.add(mirror);
+						}
+					}
+				}
+			}
+		}
+		
+		TypeMirror superclass = elem.getSuperclass();
+		if (spiTypes.isEmpty()) {
+			List<TypeMirror> qualifying = new ArrayList<TypeMirror>();
+			qualifying.addAll(elem.getInterfaces());
+			if (superclass != null && !toElement(superclass).getQualifiedName().contentEquals("java.lang.Object")) qualifying.add(superclass);
+			
+			if (qualifying.isEmpty()) {
+				report(elem, "is marked @Provides but implements/extends nothing");
+				return;
+			}
+			if (qualifying.size() > 1) {
+				report(elem, "is marked @Provides but implements/extends multiple types; explicitly specify which interface(s) this provides for");
+				return;
+			}
+			spiTypes.add(qualifying.get(0));
+		} else {
+			Deque<TypeMirror> parentage = new ArrayDeque<TypeMirror>();
+			parentage.addAll(elem.getInterfaces());
+			parentage.add(superclass);
+			List<TypeMirror> needed = new ArrayList<TypeMirror>();
+			needed.addAll(spiTypes);
+			while (!parentage.isEmpty() && !spiTypes.isEmpty()) {
+				TypeMirror parent = parentage.pollFirst();
+				if (parent == null) continue;
+				needed.remove(parent);
+				parentage.addAll(processingEnv.getTypeUtils().directSupertypes(parent));
+			}
+			if (!needed.isEmpty()) {
+				report(elem, "is marked as providing " + needed + " but does not implement it");
+				return;
+			}
+		}
+		
+		for (TypeMirror spiType : spiTypes) {
+			String spiTypeName = toElement(spiType).getQualifiedName().toString();
+			String createProperQualifiedName = createProperQualifiedName(elem);
+			data.getService(spiTypeName).addProvider(createProperQualifiedName);
+		}
+	}
+	
+	private Name getQualifiedTypeName(AnnotationMirror mirror) {
+		Element elem = mirror.getAnnotationType().asElement();
+		if (!(elem instanceof TypeElement)) return null;
+		return ((TypeElement) elem).getQualifiedName();
+	}
+	
+	private TypeElement toElement(TypeMirror typeMirror) {
+		if (typeMirror instanceof DeclaredType) {
+			Element asElement = ((DeclaredType) typeMirror).asElement();
+			if (asElement instanceof TypeElement) return (TypeElement) asElement;
+		}
+		return null;
+	}
+	
+	private void report(Element elem, String message) {
+		/* In eclipse, messages just seem to get ignored, so we throw instead. */
+		if (Boolean.TRUE) throw new RuntimeException(elem.getSimpleName() + " " + message);
+		processingEnv.getMessager().printMessage(Kind.ERROR, elem.getSimpleName() + " " + message, elem);
+	}
+	
+	private String createProperQualifiedName(TypeElement provider) {
+		return processingEnv.getElementUtils().getBinaryName(provider).toString();
+	}
+}
diff --git a/src/spiProcessor/lombok/spi/SpiProcessorCollector.java b/src/spiProcessor/lombok/spi/SpiProcessorCollector.java
new file mode 100644
index 00000000..52e557f6
--- /dev/null
+++ b/src/spiProcessor/lombok/spi/SpiProcessorCollector.java
@@ -0,0 +1,107 @@
+/*
+ * Copyright (C) 2021 The Project Lombok Authors.
+ * 
+ * Permission is hereby granted, free of charge, to any person obtaining a copy
+ * of this software and associated documentation files (the "Software"), to deal
+ * in the Software without restriction, including without limitation the rights
+ * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+ * copies of the Software, and to permit persons to whom the Software is
+ * furnished to do so, subject to the following conditions:
+ * 
+ * The above copyright notice and this permission notice shall be included in
+ * all copies or substantial portions of the Software.
+ * 
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+ * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+ * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+ * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+ * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+ * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
+ * THE SOFTWARE.
+ */
+package lombok.spi;
+
+import java.util.ArrayList;
+import java.util.Collection;
+import java.util.Collections;
+import java.util.HashMap;
+import java.util.List;
+import java.util.Map;
+
+import javax.annotation.processing.Filer;
+import javax.annotation.processing.Messager;
+import javax.annotation.processing.ProcessingEnvironment;
+import javax.lang.model.util.Elements;
+import javax.tools.Diagnostic.Kind;
+import javax.tools.FileObject;
+import javax.tools.StandardLocation;
+
+class SpiProcessorCollector {
+	private final Map<String, SpiProcessorService> services = new HashMap<String, SpiProcessorService>();
+	private final List<String> removed = new ArrayList<String>();
+	
+	private final Elements elements;
+	private final Messager logger;
+	private final Filer filer;
+	
+	SpiProcessorCollector(ProcessingEnvironment processingEnv) {
+		this.elements = processingEnv.getElementUtils();
+		this.logger = processingEnv.getMessager();
+		this.filer = processingEnv.getFiler();
+	}
+	
+	SpiProcessorCollector(Elements elements, Messager logger, Filer filer) {
+		if (elements == null) throw new NullPointerException("elements");
+		if (logger == null) throw new NullPointerException("logger");
+		if (filer == null) throw new NullPointerException("filer");
+		this.elements = elements;
+		this.logger = logger;
+		this.filer = filer;
+	}
+	
+	SpiProcessorService getService(String serviceName) {
+		if (serviceName == null) throw new NullPointerException("serviceName");
+		if (!services.containsKey(serviceName)) {
+			SpiProcessorService newService = new SpiProcessorService(serviceName);
+			CharSequence initialData = readInitialData(serviceName);
+			if (initialData != null) {
+				newService.addAllFromProvidersNameList(initialData.toString());
+				for (String provider : removed) newService.removeProvider(provider);
+			}
+			services.put(serviceName, newService);
+		}
+		return services.get(serviceName);
+	}
+	
+	Collection<SpiProcessorService> services() {
+		return Collections.unmodifiableMap(services).values();
+	}
+	
+	void removeProvider(String provider) {
+		if (provider == null) throw new NullPointerException("provider");
+		removed.add(provider);
+		for (SpiProcessorService service : services.values()) service.removeProvider(provider);
+	}
+	
+	@Override public String toString() {
+		return services.values().toString();
+	}
+	
+	private CharSequence readInitialData(String serviceName) {
+		String pathName = SpiProcessor.getRootPathOfServiceFiles() + serviceName;
+		FileObject resource;
+		
+		try {
+			resource = filer.getResource(StandardLocation.CLASS_OUTPUT, "", pathName);
+		} catch (Exception e) {
+			logger.printMessage(Kind.ERROR, SpiProcessor.toErrorMsg(e, pathName));
+			return null;
+		}
+		
+		return SpiProcessorPersistence.readFilerResource(resource, logger, pathName);
+	}
+	
+	void stripProvidersWithoutSourceFile() {
+		for (SpiProcessorService s : services.values()) s.stripProvidersWithoutSourceFile(elements);
+	}
+}
diff --git a/src/spiProcessor/lombok/spi/SpiProcessorPersistence.java b/src/spiProcessor/lombok/spi/SpiProcessorPersistence.java
new file mode 100644
index 00000000..c9bd745f
--- /dev/null
+++ b/src/spiProcessor/lombok/spi/SpiProcessorPersistence.java
@@ -0,0 +1,148 @@
+/*
+ * Copyright (C) 2021 The Project Lombok Authors.
+ * 
+ * Permission is hereby granted, free of charge, to any person obtaining a copy
+ * of this software and associated documentation files (the "Software"), to deal
+ * in the Software without restriction, including without limitation the rights
+ * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+ * copies of the Software, and to permit persons to whom the Software is
+ * furnished to do so, subject to the following conditions:
+ * 
+ * The above copyright notice and this permission notice shall be included in
+ * all copies or substantial portions of the Software.
+ * 
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+ * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+ * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+ * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+ * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+ * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
+ * THE SOFTWARE.
+ */
+package lombok.spi;
+
+import java.io.BufferedReader;
+import java.io.File;
+import java.io.FileNotFoundException;
+import java.io.IOException;
+import java.io.Reader;
+import java.io.Writer;
+import java.net.URI;
+import java.text.SimpleDateFormat;
+import java.util.ArrayList;
+import java.util.Collection;
+import java.util.Collections;
+import java.util.Date;
+import java.util.List;
+import java.util.Locale;
+
+import javax.annotation.processing.Filer;
+import javax.annotation.processing.Messager;
+import javax.tools.Diagnostic.Kind;
+import javax.tools.FileObject;
+import javax.tools.StandardLocation;
+
+class SpiProcessorPersistence {
+	private final String name;
+	private final String path;
+	final Filer filer;
+	private final Messager logger;
+	
+	SpiProcessorPersistence(String name, Filer filer, Messager logger) {
+		this.name = name;
+		this.logger = logger;
+		this.path = SpiProcessor.getRootPathOfServiceFiles();
+		this.filer = filer;
+	}
+	
+	static CharSequence readFilerResource(FileObject resource, Messager logger, String pathName) {
+		try {
+			// Eclipse can't handle getCharContent, so we must use a reader...
+			return tryWithReader(resource);
+		} catch (FileNotFoundException e) {
+			return null;
+		} catch (IOException e) {
+			if (
+				e.getClass().getName().equals("org.eclipse.core.internal.resources.ResourceException") &&
+				e.getMessage() != null &&
+				e.getMessage().endsWith("does not exist.")) {
+				
+				return null;
+			}
+			
+			logger.printMessage(Kind.ERROR, SpiProcessor.toErrorMsg(e, pathName));
+			return null;
+		} catch (Exception other) {
+			// otherwise, probably javac: Some versions don't support the `openReader` method.
+			try {
+				return resource.getCharContent(true);
+			} catch (FileNotFoundException e) {
+				return null;
+			} catch (IOException e) {
+				logger.printMessage(Kind.ERROR, SpiProcessor.toErrorMsg(e, pathName));
+				return null;
+			}
+		}
+	}
+	
+	private static CharSequence tryWithReader(FileObject resource) throws IOException {
+		StringBuilder sb = new StringBuilder();
+		Reader raw = resource.openReader(true);
+		try {
+			BufferedReader in = new BufferedReader(raw);
+			for (String line = in.readLine(); line != null; line = in.readLine()) sb.append(line).append('\n');
+			return sb;
+		} finally {
+			if (raw != null) raw.close();
+		}
+	}
+	
+	Collection<String> tryFind() {
+		File dir = determineOutputLocation();
+		if (dir == null || !dir.isDirectory()) return Collections.emptyList();
+		List<String> out = new ArrayList<String>();
+		for (File p : dir.listFiles()) {
+			if (!p.isFile()) continue;
+			out.add(p.getName());
+		}
+		return out;
+	}
+	
+	private File determineOutputLocation() {
+		FileObject resource;
+		try {
+			resource = filer.createResource(StandardLocation.CLASS_OUTPUT, "META-INF", "locator.tmp");
+		} catch (FileNotFoundException e) {
+			e.printStackTrace();
+			// Could happen
+			return null;
+		} catch (IOException e) {
+			e.printStackTrace();
+			logger.printMessage(Kind.NOTE, "IOException while determining output location: " + e.getMessage());
+			return null;
+		} catch (IllegalArgumentException e) {
+			e.printStackTrace();
+			// Happens when the path is invalid. For instance absolute or relative to a path 
+			// not part of the class output folder.
+			//
+			// Due to a bug in javac for Linux, this also occurs when no output path is specified 
+			// for javac using the -d parameter.
+			// See http://forums.sun.com/thread.jspa?threadID=5240999&tstart=45
+			// and http://bugs.sun.com/bugdatabase/view_bug.do?bug_id=6647996
+			
+			return null;
+		}
+		
+		URI uri = resource.toUri();
+		return new File(new File(uri).getParentFile(), "services");
+	}
+	
+	void write(String serviceName, String value) throws IOException {
+		FileObject output = filer.createResource(StandardLocation.CLASS_OUTPUT, "", path + serviceName);
+		Writer writer = output.openWriter();
+		writer.write("# Generated by " + name + "\n");
+		writer.write("# " + new SimpleDateFormat("EEE, d MMM yyyy HH:mm:ss Z", Locale.US).format(new Date()) + "\n");
+		writer.write(value);
+		writer.close();
+	}
+}
diff --git a/src/spiProcessor/lombok/spi/SpiProcessorService.java b/src/spiProcessor/lombok/spi/SpiProcessorService.java
new file mode 100644
index 00000000..be8d5a21
--- /dev/null
+++ b/src/spiProcessor/lombok/spi/SpiProcessorService.java
@@ -0,0 +1,83 @@
+/*
+ * Copyright (C) 2021 The Project Lombok Authors.
+ * 
+ * Permission is hereby granted, free of charge, to any person obtaining a copy
+ * of this software and associated documentation files (the "Software"), to deal
+ * in the Software without restriction, including without limitation the rights
+ * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+ * copies of the Software, and to permit persons to whom the Software is
+ * furnished to do so, subject to the following conditions:
+ * 
+ * The above copyright notice and this permission notice shall be included in
+ * all copies or substantial portions of the Software.
+ * 
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+ * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+ * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+ * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+ * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+ * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
+ * THE SOFTWARE.
+ */
+package lombok.spi;
+
+import java.util.Iterator;
+import java.util.Set;
+import java.util.TreeSet;
+import java.util.stream.Collectors;
+
+import javax.lang.model.util.Elements;
+
+final class SpiProcessorService {
+	private final String name;
+	private final Set<String> providers = new TreeSet<String>();
+	
+	SpiProcessorService(String name) {
+		if (name == null) throw new NullPointerException("name");
+		this.name = name;
+	}
+	
+	public String getName() {
+		return name;
+	}
+	
+	void addProvider(String className) {
+		if (className == null) throw new NullPointerException("className");
+		providers.add(className);
+	}
+	
+	boolean removeProvider(String provider) {
+		return providers.remove(provider);
+	}
+	
+	String toProvidersListFormat() {
+		return providers.stream().collect(Collectors.joining("\n"));
+	}
+	
+	void addAllFromProvidersNameList(String in) {
+		for (String line : in.split("\\n")) {
+			String[] content = line.split("#", 2);
+			if (content.length == 0) continue;
+			String trimmed = content[0].trim();
+			String[] elems = trimmed.split("\\s+", 2);
+			if (elems.length == 0 || elems[0].isEmpty()) continue;
+			String cn = elems[0];
+			addProvider(cn);
+		}
+	}
+	
+	void stripProvidersWithoutSourceFile(Elements elements) {
+		Iterator<String> it = providers.iterator();
+		while (it.hasNext()) {
+			if (!sourceExists(elements, it.next())) it.remove();
+		}
+	}
+	
+	private boolean sourceExists(Elements elements, String typeName) {
+		return elements.getTypeElement(typeName) != null;
+	}
+	
+	@Override public String toString() {
+		return name + " = " + providers;
+	}
+}