| /******************************************************************************* |
| * Copyright (c) 2000, 2013 IBM Corporation and others. |
| * |
| * This program and the accompanying materials |
| * are made available under the terms of the Eclipse Public License 2.0 |
| * which accompanies this distribution, and is available at |
| * https://www.eclipse.org/legal/epl-2.0/ |
| * |
| * SPDX-License-Identifier: EPL-2.0 |
| * |
| * Contributors: |
| * IBM Corporation - initial API and implementation |
| * Sergey Prigogin (Google) - Bug 421375 |
| *******************************************************************************/ |
| package org.eclipse.core.internal.expressions; |
| |
| import java.util.Arrays; |
| |
| import org.w3c.dom.Element; |
| |
| import org.eclipse.core.expressions.EvaluationResult; |
| import org.eclipse.core.expressions.Expression; |
| import org.eclipse.core.expressions.ExpressionInfo; |
| import org.eclipse.core.expressions.IEvaluationContext; |
| |
| import org.eclipse.core.runtime.Assert; |
| import org.eclipse.core.runtime.CoreException; |
| import org.eclipse.core.runtime.IAdaptable; |
| import org.eclipse.core.runtime.IAdapterManager; |
| import org.eclipse.core.runtime.IConfigurationElement; |
| import org.eclipse.core.runtime.Platform; |
| |
| public class AdaptExpression extends CompositeExpression { |
| |
| private static final String ATT_TYPE= "type"; //$NON-NLS-1$ |
| |
| /** |
| * The seed for the hash code for all adapt expressions. |
| */ |
| private static final int HASH_INITIAL= AdaptExpression.class.getName().hashCode(); |
| |
| private String fTypeName; |
| |
| public AdaptExpression(IConfigurationElement configElement) throws CoreException { |
| fTypeName= configElement.getAttribute(ATT_TYPE); |
| Expressions.checkAttribute(ATT_TYPE, fTypeName); |
| } |
| |
| public AdaptExpression(Element element) throws CoreException { |
| fTypeName= element.getAttribute(ATT_TYPE); |
| Expressions.checkAttribute(ATT_TYPE, fTypeName.length() > 0 ? fTypeName : null); |
| } |
| |
| public AdaptExpression(String typeName) { |
| Assert.isNotNull(typeName); |
| fTypeName= typeName; |
| } |
| |
| @Override |
| public boolean equals(final Object object) { |
| if (!(object instanceof AdaptExpression)) |
| return false; |
| |
| final AdaptExpression that= (AdaptExpression)object; |
| return this.fTypeName.equals(that.fTypeName) |
| && equals(this.fExpressions, that.fExpressions); |
| } |
| |
| @Override |
| protected int computeHashCode() { |
| return HASH_INITIAL * HASH_FACTOR + hashCode(fExpressions) |
| * HASH_FACTOR + fTypeName.hashCode(); |
| } |
| |
| @Override |
| public EvaluationResult evaluate(IEvaluationContext context) throws CoreException { |
| if (fTypeName == null) |
| return EvaluationResult.FALSE; |
| Object var = context.getDefaultVariable(); |
| if (var == null) { |
| return EvaluationResult.FALSE; |
| } |
| Object adapted = null; |
| IAdapterManager manager = Platform.getAdapterManager(); |
| if (Expressions.isInstanceOf(var, fTypeName)) { |
| adapted = var; |
| } else { |
| // if the adapter manager doesn't have an adapter contributed, |
| // try to see if the variable itself implements IAdaptable |
| if (var instanceof IAdaptable) { |
| Class<?> typeClazz = Expressions.loadClass(var.getClass().getClassLoader(), fTypeName); |
| if (typeClazz != null) { |
| adapted = ((IAdaptable) var).getAdapter(typeClazz); |
| } |
| } |
| |
| if (adapted == null) { |
| if (forceLoadEnabled()) { |
| adapted = manager.loadAdapter(var, fTypeName); |
| } else { |
| adapted = manager.getAdapter(var, fTypeName); |
| if (adapted == null) { |
| if (manager.queryAdapter(var, fTypeName) == IAdapterManager.NOT_LOADED) { |
| return EvaluationResult.NOT_LOADED; |
| } else { |
| return EvaluationResult.FALSE; |
| } |
| } |
| } |
| if (adapted == null) { |
| // all attempts failed, return false |
| return EvaluationResult.FALSE; |
| } |
| } |
| } |
| // the adapted result is null but hasAdapter returned true check |
| // if the adapter is loaded. |
| return evaluateAnd(new DefaultVariable(context, adapted)); |
| } |
| |
| private boolean forceLoadEnabled() { |
| return Platform.getPreferencesService().getBoolean(ExpressionPlugin.getPluginId(), "forceLoadAdapters", true, //$NON-NLS-1$ |
| null); |
| } |
| |
| @Override |
| public void collectExpressionInfo(ExpressionInfo info) { |
| // Although the default variable is passed to the children of this |
| // expression as an instance of the adapted type it is OK to only |
| // mark a default variable access. |
| info.markDefaultVariableAccessed(); |
| super.collectExpressionInfo(info); |
| } |
| |
| @Override |
| public String toString() { |
| StringBuilder builder = new StringBuilder(getClass().getSimpleName()); |
| builder.append(" [type=").append(fTypeName); //$NON-NLS-1$ |
| Expression[] children = getChildren(); |
| if (children.length > 0) { |
| builder.append(", children="); //$NON-NLS-1$ |
| builder.append(Arrays.toString(children)); |
| } |
| builder.append("]"); //$NON-NLS-1$ |
| return builder.toString(); |
| } |
| |
| } |