Merge branch 'feature/mapper-library' into dev0.6.1

1 files changed, 409 insertions, 0 deletions

diff --git a/src/main/java/ftbsc/lll/processor/utils/ASTUtils.java b/src/main/java/ftbsc/lll/processor/utils/ASTUtils.java
new file mode 100644
index 0000000..04da70e
--- /dev/null
+++ b/src/main/java/ftbsc/lll/processor/utils/ASTUtils.java
@@ -0,0 +1,409 @@
+package ftbsc.lll.processor.utils;
+
+import ftbsc.lll.exceptions.AmbiguousDefinitionException;
+import ftbsc.lll.exceptions.MappingNotFoundException;
+import ftbsc.lll.exceptions.NotAProxyException;
+import ftbsc.lll.exceptions.TargetNotFoundException;
+import ftbsc.lll.mapper.tools.Mapper;
+import ftbsc.lll.mapper.tools.data.ClassData;
+import ftbsc.lll.mapper.tools.data.FieldData;
+import ftbsc.lll.mapper.tools.data.MethodData;
+import ftbsc.lll.processor.annotations.Target;
+import ftbsc.lll.processor.containers.ClassContainer;
+import ftbsc.lll.proxies.ProxyType;
+
+import javax.annotation.processing.ProcessingEnvironment;
+import javax.lang.model.element.*;
+import javax.lang.model.type.*;
+import java.lang.annotation.Annotation;
+import java.util.Collection;
+import java.util.List;
+import java.util.function.Function;
+import java.util.stream.Collectors;
+
+/**
+ * Collection of AST-related static utils that didn't really fit into the main class.
+ */
+public class ASTUtils {
+	/**
+	 * Finds, among the methods of a class cl, the one annotated with ann, and tries to build
+	 * an {@link Element} from it.
+	 * @param parent the parent {@link Element} to the desired element
+	 * @param ann the {@link Class} corresponding to the desired annotation
+	 * @param <T> the type of {@link Element} to use
+	 * @return a {@link List} of {@link Element}s annotated with the given annotation
+	 * @since 0.2.0
+	 */
+	@SuppressWarnings("unchecked")
+	public static <T extends Element>  List<T> findAnnotatedElement(Element parent, Class<? extends Annotation> ann) {
+		return parent.getEnclosedElements()
+			.stream()
+			.filter(e -> e.getAnnotationsByType(ann).length != 0)
+			.map(e -> (T) e)
+			.collect(Collectors.toList());
+	}
+
+	/**
+	 * Maps a {@link javax.lang.model.element.Modifier} to its reflective
+	 * {@link java.lang.reflect.Modifier} equivalent.
+	 * @param m the {@link Modifier} to map
+	 * @return an integer representing the modifier
+	 * @see java.lang.reflect.Modifier
+	 * @since 0.2.0
+	 */
+	public static int mapModifier(Modifier m) {
+		switch(m) {
+			case PUBLIC:
+				return java.lang.reflect.Modifier.PUBLIC;
+			case PROTECTED:
+				return java.lang.reflect.Modifier.PROTECTED;
+			case PRIVATE:
+				return java.lang.reflect.Modifier.PRIVATE;
+			case ABSTRACT:
+				return java.lang.reflect.Modifier.ABSTRACT;
+			case STATIC:
+				return java.lang.reflect.Modifier.STATIC;
+			case FINAL:
+				return java.lang.reflect.Modifier.FINAL;
+			case TRANSIENT:
+				return java.lang.reflect.Modifier.TRANSIENT;
+			case VOLATILE:
+				return java.lang.reflect.Modifier.VOLATILE;
+			case SYNCHRONIZED:
+				return java.lang.reflect.Modifier.SYNCHRONIZED;
+			case NATIVE:
+				return java.lang.reflect.Modifier.NATIVE;
+			case STRICTFP:
+				return java.lang.reflect.Modifier.STRICT;
+			default:
+				return 0;
+		}
+	}
+
+	/**
+	 * Takes in a {@link Collection} of AST {@link Modifier}s and
+	 * returns them mapped to their reflective integer equivalent.
+	 * @param modifiers the {@link Modifier}s
+	 * @return an integer value representing them
+	 * @since 0.5.0
+	 */
+	public static int mapModifiers(Collection<Modifier> modifiers) {
+		int i = 0;
+		for(Modifier m : modifiers)
+			i |= mapModifier(m);
+		return i;
+	}
+
+	/**
+	 * Safely extracts a {@link Class} from an annotation and gets a {@link TypeMirror} representing it.
+	 * @param ann the annotation containing the class
+	 * @param classFunction the annotation function returning the class
+	 * @param env the {@link ProcessingEnvironment} to perform the operation in
+	 * @param <T> the type of the annotation carrying the information
+	 * @return a {@link TypeMirror} representing the requested {@link Class}
+	 * @since 0.3.0
+	 */
+	public static <T extends Annotation> TypeMirror getTypeFromAnnotation(
+		T ann, Function<T, Class<?>> classFunction, ProcessingEnvironment env) {
+		try {
+			String fqn = classFunction.apply(ann).getCanonicalName();
+			if(fqn == null)
+				fqn = "";
+			return env.getElementUtils().getTypeElement(fqn).asType();
+		} catch(MirroredTypeException e) {
+			return e.getTypeMirror();
+		}
+	}
+
+	/**
+	 * Gets the internal name from an {@link TypeMirror}.
+	 * @param type the {@link TypeMirror} in question
+	 * @param env the {@link ProcessingEnvironment} to perform the operation in
+	 * @return the internal name at compile time, or null if it wasn't a qualifiable
+	 * @since 0.5.1
+	 */
+	public static String internalNameFromType(TypeMirror type, ProcessingEnvironment env) {
+		//needed to actually turn elem into a TypeVariable, find it ignoring generics
+		Element elem = env.getTypeUtils().asElement(env.getTypeUtils().erasure(type));
+		StringBuilder fqnBuilder = new StringBuilder();
+		while(elem.getEnclosingElement() != null && elem.getEnclosingElement().getKind() != ElementKind.PACKAGE) {
+			fqnBuilder
+				.insert(0, elem.getSimpleName().toString())
+				.insert(0, "$");
+			elem = elem.getEnclosingElement();
+		}
+		return fqnBuilder
+			.insert(0, env.getTypeUtils().erasure(elem.asType()).toString())
+			.toString()
+			.replace('.', '/');
+	}
+
+	/**
+	 * Builds a type descriptor from the given {@link TypeMirror}.
+	 * @param t the {@link TypeMirror} representing the desired type
+	 * @param env the {@link ProcessingEnvironment} to perform the operation in
+	 * @return a {@link String} containing the relevant descriptor
+	 */
+	public static String descriptorFromType(TypeMirror t, ProcessingEnvironment env) {
+		t = env.getTypeUtils().erasure(t); //type erasure
+
+		StringBuilder desc = new StringBuilder();
+		//add array brackets
+		while(t.getKind() == TypeKind.ARRAY) {
+			desc.append("[");
+			t = ((ArrayType) t).getComponentType();
+		}
+
+		if(t.getKind() == TypeKind.TYPEVAR)
+			t = ((TypeVariable) t).getUpperBound();
+
+		if(t.getKind() == TypeKind.DECLARED)
+			desc
+				.append("L")
+				.append(internalNameFromType(t, env))
+				.append(";");
+		else {
+			switch(t.getKind()) {
+				case BOOLEAN:
+					desc.append("Z");
+					break;
+				case CHAR:
+					desc.append("C");
+					break;
+				case BYTE:
+					desc.append("B");
+					break;
+				case SHORT:
+					desc.append("S");
+					break;
+				case INT:
+					desc.append("I");
+					break;
+				case FLOAT:
+					desc.append("F");
+					break;
+				case LONG:
+					desc.append("J");
+					break;
+				case DOUBLE:
+					desc.append("D");
+					break;
+				case VOID:
+					desc.append("V");
+					break;
+			}
+		}
+
+		return desc.toString();
+	}
+
+	/**
+	 * Builds a method descriptor from the given {@link ExecutableElement}.
+	 * @param m the {@link ExecutableElement} for the method
+	 * @param env the {@link ProcessingEnvironment} to perform the operation in
+	 * @return a {@link String} containing the relevant descriptor
+	 */
+	public static String descriptorFromExecutableElement(ExecutableElement m, ProcessingEnvironment env) {
+		StringBuilder methodSignature = new StringBuilder();
+		methodSignature.append("(");
+		m.getParameters().forEach(p -> methodSignature.append(descriptorFromType(p.asType(), env)));
+		methodSignature.append(")");
+		methodSignature.append(descriptorFromType(m.getReturnType(), env));
+		return methodSignature.toString();
+	}
+
+	/**
+	 * Gets the {@link ClassData} corresponding to the given fully-qualified name,
+	 * or creates a false one with the same, non-obfuscated name twice.
+	 * @param name the internal name of the class to convert
+	 * @param mapper the {@link Mapper} to use, may be null
+	 * @return the fully qualified class name
+	 * @since 0.6.1
+	 */
+	public static ClassData getClassData(String name, Mapper mapper) {
+		try {
+			name = name.replace('.', '/'); //just in case
+			if(mapper != null)
+				return mapper.getClassData(name);
+		} catch(MappingNotFoundException ignored) {}
+		return new ClassData(name, name);
+	}
+
+	/**
+	 * Gets the {@link MethodData} corresponding to the method matching the given
+	 * name, parent and descriptor, or creates a dummy one with fake data if no
+	 * valid mapping is found.
+	 * @param parent the internal name of the parent class
+	 * @param name the name of the member
+	 * @param descriptor the descriptor of the method
+	 * @param mapper the {@link Mapper} to use, may be null
+	 * @return the fully qualified class name
+	 * @since 0.6.1
+	 */
+	public static MethodData getMethodData(String parent, String name, String descriptor, Mapper mapper) {
+		try {
+			name = name.replace('.', '/'); //just in case
+			if(mapper != null)
+				return mapper.getMethodData(parent, name, descriptor);
+		} catch(MappingNotFoundException ignored) {}
+		return new MethodData(getClassData(name, mapper), name, name, descriptor);
+	}
+
+	/**
+	 * Gets the {@link FieldData} corresponding to the field matching the given
+	 * name and parent, or creates a dummy one with fake data if no valid
+	 * mapping is found.
+	 * @param parent the internal name of the parent class
+	 * @param name the name of the member
+	 * @param mapper the {@link Mapper} to use, may be null
+	 * @return the fully qualified class name
+	 * @since 0.6.1
+	 */
+	public static FieldData getFieldData(String parent, String name, Mapper mapper) {
+		try {
+			name = name.replace('.', '/'); //just in case
+			if(mapper != null)
+				return mapper.getFieldData(parent, name);
+		} catch(MappingNotFoundException ignored) {}
+		return new FieldData(getClassData(name, mapper), name, name);
+	}
+
+	/**
+	 * Finds a member given the name, the container class and (if it's a method) the descriptor.
+	 * @param parent the {@link ClassContainer} representing the parent
+	 * @param name the name to search for
+	 * @param descr the descriptor to search for, or null if it's not a method
+	 * @param strict whether to perform lookup in strict mode (see {@link Target#strict()} for more information)
+	 * @param field whether the member being searched is a field
+	 * @param env the {@link ProcessingEnvironment} to perform the operation in
+	 * @return the desired member, if it exists
+	 * @throws AmbiguousDefinitionException if it finds more than one candidate
+	 * @throws TargetNotFoundException if it finds no valid candidate
+	 * @since 0.3.0
+	 */
+	public static Element findMember(
+		ClassContainer parent, String name, String descr,
+		boolean strict, boolean field, ProcessingEnvironment env) {
+		if(parent.elem == null)
+			throw new TargetNotFoundException("parent class", parent.data.name);
+		//try to find by name
+		List<Element> candidates = parent.elem.getEnclosedElements()
+			.stream()
+			.filter(e -> (field && e instanceof VariableElement) || e instanceof ExecutableElement)
+			.filter(e -> e.getSimpleName().contentEquals(name))
+			.collect(Collectors.toList());
+
+		if(candidates.isEmpty())
+			throw new TargetNotFoundException(field ? "field" : "method", name, parent.data.name);
+
+		if(candidates.size() == 1 && (!strict || descr == null))
+			return candidates.get(0);
+
+		if(descr == null) {
+			throw new AmbiguousDefinitionException(String.format(
+				"Found %d members named %s in class %s!", candidates.size(), name, parent.data.name));
+		} else {
+			if(field) {
+				//fields can verify the signature for extra safety
+				//but there can only be 1 field with a given name
+				if(!descriptorFromType(candidates.get(0).asType(), env).equals(descr))
+					throw new TargetNotFoundException("field", String.format(
+						"%s with descriptor %s", name, descr), parent.data.name);
+			} else {
+				candidates = candidates.stream()
+					.map(e -> (ExecutableElement) e)
+					.filter(strict
+						? c -> descr.equals(descriptorFromExecutableElement(c, env))
+						: c -> descr.split("\\)")[0].equalsIgnoreCase(
+							descriptorFromExecutableElement(c, env).split("\\)")[0])
+					).collect(Collectors.toList());
+			}
+			if(candidates.isEmpty())
+				throw new TargetNotFoundException("method", String.format(
+					"%s %s", name, descr), parent.data.name);
+			if(candidates.size() > 1)
+				throw new AmbiguousDefinitionException(String.format(
+					"Found %d methods named %s in class %s!", candidates.size(), name, parent.data.name));
+			return candidates.get(0);
+		}
+	}
+
+	/**
+	 * Tries to find the method being overloaded by the given {@link ExecutableElement}.
+	 * In case of multiple layers of overloading, it finds the original one. In case of
+	 * no overloading, it returns the given method.
+	 * @param context the {@link TypeElement} representing the parent class
+	 * @param method an {@link ExecutableElement} representing the overloading method
+	 * @param env the {@link ProcessingEnvironment} to perform the operation in
+	 * @return the original overloaded method, or the given method if it was not found
+	 * @since 0.5.2
+	 */
+	public static ExecutableElement findOverloadedMethod(
+		TypeElement context, ExecutableElement method, ProcessingEnvironment env) {
+		if (context.getSuperclass().getKind() == TypeKind.NONE)
+			return method;
+
+		for (Element elem : context.getEnclosedElements()) {
+			if (elem.getKind() != ElementKind.METHOD)
+				continue;
+			if (env.getElementUtils().overrides(method, (ExecutableElement) elem, context)) {
+				method = (ExecutableElement) elem;
+				break; //found
+			}
+		}
+
+		return findOverloadedMethod(
+			(TypeElement) env.getTypeUtils().asElement(context.getSuperclass()),
+			method, env
+		);
+	}
+
+	/**
+	 * Tries to find the "synthetic bridge" generated by the compiler for a certain overridden
+	 * method. A "bridge" only exists in cases where type erasure is involved (i.e. when the
+	 * method being overridden uses a generic parameter that is not preserved in the overriding
+	 * method).
+	 * @param context the {@link TypeElement} representing the parent class
+	 * @param method an {@link ExecutableElement} stub representing the overloading method
+	 * @param env the {@link ProcessingEnvironment} to perform the operation in
+	 * @return the "bridge"
+	 * @throws TargetNotFoundException if the method in question was not overriding anything, or
+	 * 																 if the method it was overriding does not require a bridge
+	 * @since 0.5.2
+	 */
+	public static ExecutableElement findSyntheticBridge(
+		TypeElement context, ExecutableElement method, ProcessingEnvironment env) throws TargetNotFoundException {
+		ExecutableElement overridding = findOverloadedMethod(context, method, env);
+		if(descriptorFromExecutableElement(overridding, env).equals(descriptorFromExecutableElement(method, env)))
+			throw new TargetNotFoundException(
+				"bridge method for",
+				overridding.getSimpleName().toString(),
+				context.getQualifiedName().toString()
+			);
+		else return overridding;
+	}
+
+	/**
+	 * Utility method for finding out what type of proxy a field is.
+	 * It will fail if the return type is not a known type of proxy.
+	 * @param v the annotated {@link VariableElement}
+	 * @return the {@link ProxyType} for the element
+	 * @throws NotAProxyException if it's neither
+	 * @since 0.4.0
+	 */
+	public static ProxyType getProxyType(VariableElement v) {
+		String returnTypeFQN = v.asType().toString();
+		switch(returnTypeFQN) {
+			case "ftbsc.lll.proxies.impl.FieldProxy":
+				return ProxyType.FIELD;
+			case "ftbsc.lll.proxies.impl.MethodProxy":
+				return ProxyType.METHOD;
+			case "ftbsc.lll.proxies.impl.TypeProxy":
+				return ProxyType.TYPE;
+			case "ftbsc.lll.proxies.impl.PackageProxy":
+				return ProxyType.PACKAGE;
+			default:
+				throw new NotAProxyException(v.getEnclosingElement().getSimpleName().toString(), v.getSimpleName().toString());
+		}
+	}
+}