| /******************************************************************************* |
| * Copyright (c) 2009, 2010 IBM Corporation and others. |
| * All rights reserved. This program and the accompanying materials |
| * are made available under the terms of the Eclipse Public License v1.0 |
| * which accompanies this distribution, and is available at |
| * http://www.eclipse.org/legal/epl-v10.html |
| * |
| * Contributors: |
| * IBM Corporation - initial API and implementation |
| *******************************************************************************/ |
| package org.eclipse.e4.core.services.internal.context; |
| |
| import java.lang.reflect.InvocationTargetException; |
| import java.lang.reflect.Method; |
| import org.eclipse.e4.core.services.context.ContextChangeEvent; |
| import org.eclipse.e4.core.services.injector.IObjectProvider; |
| import org.eclipse.e4.core.services.injector.ObjectDescriptor; |
| |
| /** |
| * Collection of static methods that deal with reflection-based injection at a low level. |
| */ |
| public class InjectionMethod extends InjectionAbstract { |
| |
| private final Method method; |
| |
| public InjectionMethod(Object userObject, IObjectProvider primarySupplier, Method method, |
| boolean batchProcess) { |
| super(userObject, primarySupplier, batchProcess); |
| this.method = method; |
| InjectionProperties methodProps = annotationSupport.getInjectProperties(method, |
| primarySupplier); |
| optional = methodProps.isOptional(); |
| } |
| |
| public boolean notify(ContextChangeEvent event) { |
| Object userObject = getObject(); |
| if (userObject == null) |
| return false; |
| int eventType = event.getEventType(); |
| IObjectProvider changed = event.getContext(); |
| boolean ignoreMissing = ignoreMissing(eventType, changed); |
| boolean injectWithNulls = injectNulls(eventType, changed); |
| try { |
| invoke(ignoreMissing, injectWithNulls); |
| } catch (InjectionException e) { |
| logError(method, e); |
| return false; |
| } |
| if (eventType == ContextChangeEvent.DISPOSE && primarySupplier.equals(changed)) |
| return false; |
| return true; |
| } |
| |
| public Object invoke(boolean ignoreMissing, boolean injectWithNulls) throws InjectionException { |
| Object[] actualParams = processParams(ignoreMissing, injectWithNulls); |
| if (actualParams == null) { |
| if (!optional) { |
| String msg = "Unable to find matching argument to call method \"" |
| + method.getName() + "\""; |
| throw new InjectionException(msg); |
| } |
| return null; |
| } |
| try { |
| return callMethod(actualParams); |
| } catch (InvocationTargetException e) { |
| String msg = "Unexpected error invoking method \"" + method.getName() + "\""; |
| throw new InjectionException(msg, e); |
| } |
| } |
| |
| private Object[] processParams(boolean ignoreMissing, boolean injectWithNulls) { |
| Class[] parameterTypes = method.getParameterTypes(); |
| InjectionProperties[] properties = annotationSupport.getInjectParamProperties(method, |
| primarySupplier); |
| Object[] actualParams = new Object[properties.length]; |
| for (int i = 0; i < actualParams.length; i++) { |
| try { |
| ObjectDescriptor objectDescriptor = ObjectDescriptor.make(parameterTypes[i], |
| properties[i].getPropertyName()); |
| Object actualValue = getValue(objectDescriptor, properties[i], parameterTypes[i], |
| ignoreMissing, injectWithNulls); |
| if (actualValue == NOT_A_VALUE) |
| return null; |
| actualParams[i] = actualValue; |
| } catch (IllegalArgumentException e) { |
| String msg = "Could not invoke " + method.getName(); |
| logError(msg, e); |
| return null; |
| } |
| } |
| return actualParams; |
| } |
| |
| private Object callMethod(Object[] args) throws InvocationTargetException { |
| Object userObject = getObject(); |
| Object result = null; |
| boolean wasAccessible = true; |
| if (!method.isAccessible()) { |
| method.setAccessible(true); |
| wasAccessible = false; |
| } |
| try { |
| result = method.invoke(userObject, args); |
| } catch (IllegalArgumentException e) { |
| // should not happen, is checked during formation of the array of actual arguments |
| logError(method, e); |
| return null; |
| } catch (IllegalAccessException e) { |
| // should not happen, is checked at the start of this method |
| logError(method, e); |
| return null; |
| } finally { |
| if (!wasAccessible) |
| method.setAccessible(false); |
| } |
| return result; |
| } |
| } |