| /* |
| * Licensed to the Apache Software Foundation (ASF) under one |
| * or more contributor license agreements. See the NOTICE file |
| * distributed with this work for additional information |
| * regarding copyright ownership. The ASF licenses this file |
| * to you 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.apache.ode.il; |
| |
| import java.lang.reflect.Array; |
| import java.lang.reflect.InvocationTargetException; |
| import java.lang.reflect.Method; |
| import java.util.ArrayList; |
| import java.util.Iterator; |
| import java.util.List; |
| |
| import javax.xml.namespace.QName; |
| import javax.xml.stream.XMLStreamException; |
| import javax.xml.stream.XMLStreamReader; |
| |
| import org.apache.axiom.om.OMAbstractFactory; |
| import org.apache.axiom.om.OMElement; |
| import org.apache.axiom.om.OMFactory; |
| import org.apache.axiom.om.impl.builder.StAXOMBuilder; |
| import org.apache.commons.logging.Log; |
| import org.apache.commons.logging.LogFactory; |
| import org.apache.ode.bpel.pmapi.ProcessInfoCustomizer; |
| import org.apache.xmlbeans.XmlObject; |
| import org.w3c.dom.Node; |
| |
| /** |
| * Dynamic invocation handler for XML-based service; uses RPC message format conventions to dispatch |
| * invocation based on top-level element name (e.g. method name) and sub-elements (e.g. parameters). |
| */ |
| public class DynamicService<T> { |
| private final Log __log = LogFactory.getLog(getClass()); |
| |
| static final OMFactory OM = OMAbstractFactory.getOMFactory(); |
| |
| T _service; |
| Class<T> _clazz; |
| |
| @SuppressWarnings("unchecked") |
| public DynamicService(T service) { |
| _clazz = (Class<T>) service.getClass(); |
| _service = service; |
| } |
| |
| public OMElement invoke(String operation, OMElement payload) { |
| if (__log.isDebugEnabled()) |
| __log.debug("Invoke: operation "+operation+" on "+_clazz + ":\n" + payload); |
| |
| String methodName = operation; |
| try { |
| Method invokedMethod = findMethod(methodName); |
| Object[] params = extractParams(invokedMethod, payload); |
| Object result = invokedMethod.invoke(_service, params); |
| OMElement response = null; |
| if (result != null) { |
| response = OM.createOMElement(new QName(payload.getNamespace().getNamespaceURI(), methodName+"Response")); |
| OMElement parts = convertToOM(result); |
| parts = stripNamespace(parts); |
| response.addChild(parts); |
| } |
| if (__log.isDebugEnabled()) { |
| __log.debug("Response: operation "+operation+" on "+_clazz + ":\n" + response); |
| } |
| return response; |
| } catch (IllegalAccessException e) { |
| throw new RuntimeException("Couldn't invoke method named " + methodName + " in management interface!", e); |
| } catch (InvocationTargetException e) { |
| throw new RuntimeException("Invocation of method " + methodName + " in management interface failed: " + e.getTargetException().getMessage(), e.getTargetException()); |
| } |
| } |
| |
| @SuppressWarnings("unchecked") |
| private Object[] extractParams(Method method, OMElement omElmt) { |
| Class<?>[] paramTypes = method.getParameterTypes(); |
| Object[] params = new Object[method.getParameterTypes().length]; |
| Iterator<OMElement> omChildren = (Iterator<OMElement>) omElmt.getChildElements(); |
| int paramIdx = 0; |
| for (Class<?> paramClass : paramTypes) { |
| OMElement omchild = (OMElement) omChildren.next(); |
| __log.debug("Extracting param " + paramClass + " from " + omchild); |
| params[paramIdx++] = convertFromOM(paramClass, omchild); |
| } |
| return params; |
| } |
| |
| @SuppressWarnings("unchecked") |
| private static Object convertFromOM(Class<?> clazz, OMElement elmt) { |
| // Here comes the nasty code... |
| if (elmt == null || elmt.getText().length() == 0 && !elmt.getChildElements().hasNext()) |
| return null; |
| else if (clazz.equals(String.class)) { |
| return elmt.getText(); |
| } else if (clazz.equals(Boolean.class) || clazz.equals(Boolean.TYPE)) { |
| return (elmt.getText().equals("true") || elmt.getText().equals("yes")) ? Boolean.TRUE : Boolean.FALSE; |
| } else if (clazz.equals(QName.class)) { |
| // The getTextAsQName is buggy, it sometimes return the full text without extracting namespace |
| return OMUtils.getTextAsQName(elmt); |
| } else if (clazz.equals(ProcessInfoCustomizer.class)) { |
| return new ProcessInfoCustomizer(elmt.getText()); |
| } else if (Node.class.isAssignableFrom(clazz)) { |
| return OMUtils.toDOM(elmt.getFirstElement()); |
| } else if (clazz.equals(Long.TYPE) || clazz.equals(Long.class)) { |
| return Long.parseLong(elmt.getText()); |
| } else if (clazz.equals(Integer.TYPE) || clazz.equals(Integer.class)) { |
| return Integer.parseInt(elmt.getText()); |
| } else if (clazz.isArray()) { |
| ArrayList<Object> alist = new ArrayList<Object>(); |
| Iterator<OMElement> children = elmt.getChildElements(); |
| Class<?> targetClazz = clazz.getComponentType(); |
| while (children.hasNext()) |
| alist.add(parseType(targetClazz, ((OMElement)children.next()).getText())); |
| return alist.toArray((Object[]) Array.newInstance(targetClazz, alist.size())); |
| } else if (XmlObject.class.isAssignableFrom(clazz)) { |
| try { |
| Class beanFactory = Class.forName(clazz.getCanonicalName() + ".Factory"); |
| return beanFactory.getMethod("parse", XMLStreamReader.class) |
| .invoke(elmt.getXMLStreamReaderWithoutCaching()); |
| } catch (ClassNotFoundException e) { |
| throw new RuntimeException("Couldn't find class " + clazz.getCanonicalName() + ".Factory to instantiate xml bean", e); |
| } catch (IllegalAccessException e) { |
| throw new RuntimeException("Couldn't access class " + clazz.getCanonicalName() + ".Factory to instantiate xml bean", e); |
| } catch (InvocationTargetException e) { |
| throw new RuntimeException("Couldn't access xml bean parse method on class " + clazz.getCanonicalName() + ".Factory " + |
| "to instantiate xml bean", e); |
| } catch (NoSuchMethodException e) { |
| throw new RuntimeException("Couldn't find xml bean parse method on class " + clazz.getCanonicalName() + ".Factory " + |
| "to instantiate xml bean", e); |
| } |
| } else throw new RuntimeException("Couldn't use element " + elmt + " to obtain a management method parameter."); |
| } |
| |
| @SuppressWarnings("unchecked") |
| private static OMElement convertToOM(Object obj) { |
| if (obj instanceof XmlObject) { |
| try { |
| return new StAXOMBuilder(((XmlObject)obj).newInputStream()).getDocumentElement(); |
| } catch (XMLStreamException e) { |
| throw new RuntimeException("Couldn't serialize result to an outgoing messages.", e); |
| } |
| } else if (obj instanceof List) { |
| OMElement listElmt = OM.createOMElement("list", null); |
| for (Object stuff : ((List) obj)) { |
| OMElement stuffElmt = OM.createOMElement("element", null); |
| stuffElmt.setText(stuff.toString()); |
| listElmt.addChild(stuffElmt); |
| } |
| return listElmt; |
| } else throw new RuntimeException("Couldn't convert object " + obj + " into a response element."); |
| } |
| |
| @SuppressWarnings("unchecked") |
| private static OMElement stripNamespace(OMElement element) { |
| OMElement parent = OM.createOMElement(new QName("", element.getLocalName())); |
| Iterator<OMElement> iter = (Iterator<OMElement>) element.getChildElements(); |
| while (iter.hasNext()) { |
| OMElement child = iter.next(); |
| child = child.cloneOMElement(); |
| parent.addChild(child); |
| } |
| return parent; |
| } |
| |
| private Method findMethod(String methodName) { |
| for (Method method : _clazz.getMethods()) { |
| if (method.getName().equals(methodName)) return method; |
| } |
| throw new RuntimeException("Couldn't find any method named " + methodName + " in interface " + _clazz.getName()); |
| } |
| |
| private static Object parseType(Class<?> clazz, String str) { |
| if (clazz.equals(Integer.class)) return Integer.valueOf(str); |
| if (clazz.equals(Float.class)) return Integer.valueOf(str); |
| if (clazz.equals(String.class)) return str; |
| return null; |
| } |
| |
| } |