/* * Copyright 2002-2017 the original author or authors. * * Licensed under the Apache License, Version 2.0 (the "License"); * you may not use this file except in compliance with the License. * You may obtain a copy of the License at * * http://www.apache.org/licenses/LICENSE-2.0 * * Unless required by applicable law or agreed to in writing, software * distributed under the License is distributed on an "AS IS" BASIS, * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. * See the License for the specific language governing permissions and * limitations under the License. */ package org.springframework.scripting.jruby; import java.lang.reflect.Array; import java.lang.reflect.InvocationHandler; import java.lang.reflect.Method; import java.lang.reflect.Proxy; import java.util.Collections; import java.util.List; import org.jruby.Ruby; import org.jruby.RubyArray; import org.jruby.RubyNil; import org.jruby.ast.ClassNode; import org.jruby.ast.Colon2Node; import org.jruby.ast.NewlineNode; import org.jruby.ast.Node; import org.jruby.exceptions.JumpException; import org.jruby.exceptions.RaiseException; import org.jruby.javasupport.JavaEmbedUtils; import org.jruby.runtime.builtin.IRubyObject; import org.springframework.core.NestedRuntimeException; import org.springframework.util.ClassUtils; import org.springframework.util.ObjectUtils; import org.springframework.util.ReflectionUtils; import org.springframework.util.StringUtils; /** * Utility methods for handling JRuby-scripted objects. * * <p>Note: Spring 4.0 supports JRuby 1.5 and higher, with 1.7.x recommended. * As of Spring 4.2, JRuby 9.0.0.0 is supported as well but primarily through * {@link org.springframework.scripting.support.StandardScriptFactory}. * * @author Rob Harrop * @author Juergen Hoeller * @author Rick Evans * @since 2.0 * @deprecated in favor of JRuby support via the JSR-223 abstraction * ({@link org.springframework.scripting.support.StandardScriptFactory}) */ @Deprecated public abstract class JRubyScriptUtils { /** * Create a new JRuby-scripted object from the given script source, * using the default {@link ClassLoader}. * @param scriptSource the script source text * @param interfaces the interfaces that the scripted Java object is to implement * @return the scripted Java object * @throws JumpException in case of JRuby parsing failure * @see ClassUtils#getDefaultClassLoader() */ public static Object createJRubyObject(String scriptSource, Class<?>... interfaces) throws JumpException { return createJRubyObject(scriptSource, interfaces, ClassUtils.getDefaultClassLoader()); } /** * Create a new JRuby-scripted object from the given script source. * @param scriptSource the script source text * @param interfaces the interfaces that the scripted Java object is to implement * @param classLoader the {@link ClassLoader} to create the script proxy with * @return the scripted Java object * @throws JumpException in case of JRuby parsing failure */ public static Object createJRubyObject(String scriptSource, Class<?>[] interfaces, ClassLoader classLoader) { Ruby ruby = initializeRuntime(); Node scriptRootNode = ruby.parseEval(scriptSource, "", null, 0); IRubyObject rubyObject = ruby.runNormally(scriptRootNode); if (rubyObject instanceof RubyNil) { String className = findClassName(scriptRootNode); rubyObject = ruby.evalScriptlet("\n" + className + ".new"); } // still null? if (rubyObject instanceof RubyNil) { throw new IllegalStateException("Compilation of JRuby script returned RubyNil: " + rubyObject); } return Proxy.newProxyInstance(classLoader, interfaces, new RubyObjectInvocationHandler(rubyObject, ruby)); } /** * Initializes an instance of the {@link org.jruby.Ruby} runtime. */ @SuppressWarnings("unchecked") private static Ruby initializeRuntime() { return JavaEmbedUtils.initialize(Collections.EMPTY_LIST); } /** * Given the root {@link Node} in a JRuby AST will locate the name of the * class defined by that AST. * @throws IllegalArgumentException if no class is defined by the supplied AST */ private static String findClassName(Node rootNode) { ClassNode classNode = findClassNode(rootNode); if (classNode == null) { throw new IllegalArgumentException("Unable to determine class name for root node '" + rootNode + "'"); } Colon2Node node = (Colon2Node) classNode.getCPath(); return node.getName(); } /** * Find the first {@link ClassNode} under the supplied {@link Node}. * @return the corresponding {@code ClassNode}, or {@code null} if none found */ private static ClassNode findClassNode(Node node) { if (node == null) { return null; } if (node instanceof ClassNode) { return (ClassNode) node; } List<Node> children = node.childNodes(); for (Node child : children) { if (child instanceof ClassNode) { return (ClassNode) child; } else if (child instanceof NewlineNode) { NewlineNode nn = (NewlineNode) child; ClassNode found = findClassNode(nn.getNextNode()); if (found != null) { return found; } } } for (Node child : children) { ClassNode found = findClassNode(child); if (found != null) { return found; } } return null; } /** * InvocationHandler that invokes a JRuby script method. */ private static class RubyObjectInvocationHandler implements InvocationHandler { private final IRubyObject rubyObject; private final Ruby ruby; public RubyObjectInvocationHandler(IRubyObject rubyObject, Ruby ruby) { this.rubyObject = rubyObject; this.ruby = ruby; } @Override public Object invoke(Object proxy, Method method, Object[] args) throws Throwable { if (ReflectionUtils.isEqualsMethod(method)) { return (isProxyForSameRubyObject(args[0])); } else if (ReflectionUtils.isHashCodeMethod(method)) { return this.rubyObject.hashCode(); } else if (ReflectionUtils.isToStringMethod(method)) { String toStringResult = this.rubyObject.toString(); if (!StringUtils.hasText(toStringResult)) { toStringResult = ObjectUtils.identityToString(this.rubyObject); } return "JRuby object [" + toStringResult + "]"; } try { IRubyObject[] rubyArgs = convertToRuby(args); IRubyObject rubyResult = this.rubyObject.callMethod(this.ruby.getCurrentContext(), method.getName(), rubyArgs); return convertFromRuby(rubyResult, method.getReturnType()); } catch (RaiseException ex) { throw new JRubyExecutionException(ex); } } private boolean isProxyForSameRubyObject(Object other) { if (!Proxy.isProxyClass(other.getClass())) { return false; } InvocationHandler ih = Proxy.getInvocationHandler(other); return (ih instanceof RubyObjectInvocationHandler && this.rubyObject.equals(((RubyObjectInvocationHandler) ih).rubyObject)); } private IRubyObject[] convertToRuby(Object[] javaArgs) { if (javaArgs == null || javaArgs.length == 0) { return new IRubyObject[0]; } IRubyObject[] rubyArgs = new IRubyObject[javaArgs.length]; for (int i = 0; i < javaArgs.length; ++i) { rubyArgs[i] = JavaEmbedUtils.javaToRuby(this.ruby, javaArgs[i]); } return rubyArgs; } private Object convertFromRuby(IRubyObject rubyResult, Class<?> returnType) { Object result = JavaEmbedUtils.rubyToJava(this.ruby, rubyResult, returnType); if (result instanceof RubyArray && returnType.isArray()) { result = convertFromRubyArray(((RubyArray) result).toJavaArray(), returnType); } return result; } private Object convertFromRubyArray(IRubyObject[] rubyArray, Class<?> returnType) { Class<?> targetType = returnType.getComponentType(); Object javaArray = Array.newInstance(targetType, rubyArray.length); for (int i = 0; i < rubyArray.length; i++) { IRubyObject rubyObject = rubyArray[i]; Array.set(javaArray, i, convertFromRuby(rubyObject, targetType)); } return javaArray; } } /** * Exception thrown in response to a JRuby {@link RaiseException} * being thrown from a JRuby method invocation. */ @SuppressWarnings("serial") public static class JRubyExecutionException extends NestedRuntimeException { /** * Create a new {@code JRubyException}, * wrapping the given JRuby {@code RaiseException}. * @param ex the cause (must not be {@code null}) */ public JRubyExecutionException(RaiseException ex) { super(ex.getMessage(), ex); } } }