/*******************************************************************************
* Copyright (c) 2005, 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.che.ide.ext.java.jdt.core.dom;
import org.eclipse.che.ide.ext.java.jdt.internal.compiler.env.ICompilationUnit;
/**
* An AST requestor handles ASTs for compilation units passed to
* {@link ASTParser#createASTs(ICompilationUnit[], String[], ASTRequestor, org.eclipse.core.runtime.IProgressMonitor)
* ASTParser.createASTs}.
* <p>
* {@link #acceptAST(ICompilationUnit, CompilationUnit) ASTRequestor.acceptAST} is called for each of the compilation units passed
* to {@link ASTParser#createASTs(ICompilationUnit[], String[], ASTRequestor, org.eclipse.core.runtime.IProgressMonitor)
* ASTParser.createASTs}. After all the compilation units have been processed, {@link #acceptBinding(String, IBinding)
* ASTRequestor.acceptBindings} is called for each of the binding keys passed to
* {@link ASTParser#createASTs(ICompilationUnit[], String[], ASTRequestor, org.eclipse.core.runtime.IProgressMonitor)
* ASTParser.createASTs}.
* </p>
* <p>
* This class is intended to be subclassed by clients. AST requestors are serially reusable, but neither reentrant nor
* thread-safe.
* </p>
*
* @see ASTParser#createASTs(ICompilationUnit[], String[], ASTRequestor, org.eclipse.core.runtime.IProgressMonitor)
* @since 3.1
*/
public abstract class ASTRequestor {
/**
* The compilation unit resolver used to resolve bindings, or <code>null</code> if none. Note that this field is non-null only
* within the dynamic scope of a call to <code>ASTParser.createASTs</code>.
*/
CompilationUnitResolver compilationUnitResolver = null;
/** Creates a new instance. */
protected ASTRequestor() {
// do nothing
}
/**
* Accepts a binding corresponding to the binding key. That is, <code>binding</code> is the binding for <code>bindingKey</code>
* ; <code>binding</code> is <code>null</code> if the key cannot be resolved.
* <p>
* The default implementation of this method does nothing. Clients should override to process the resulting binding.
* </p>
*
* @param bindingKey
* the key of the requested binding
* @param binding
* the requested binding, or <code>null</code> if none
*/
public void acceptBinding(String bindingKey, IBinding binding) {
// do nothing
}
/**
* Resolves bindings for the given binding keys. The given binding keys must have been obtained earlier using
* {@link IBinding#getKey()}.
* <p>
* If a binding key cannot be resolved, <code>null</code> is put in the resulting array. Bindings can only be resolved in the
* dynamic scope of a <code>ASTParser.createASTs</code>, and only if <code>ASTParser.resolveBindings(true)</code> was
* specified.
* </p>
* <p>
* Caveat: During an <code>acceptAST</code> callback, there are implementation limitations concerning the look up of binding
* keys representing local elements. In some cases, the binding is unavailable, and <code>null</code> will be returned. This is
* only an issue during an <code>acceptAST</code> callback, and only when the binding key represents a local element (e.g.,
* local variable, local class, method declared in anonymous class). There is no such limitation outside of
* <code>acceptAST</code> callbacks, or for top-level types and their members even within <code>acceptAST</code> callbacks.
* </p>
*
* @param bindingKeys
* the binding keys to look up
* @return a list of bindings paralleling the <code>bindingKeys</code> parameter, with <code>null</code> entries for keys that
* could not be resolved
*/
public final IBinding[] createBindings(String[] bindingKeys) {
int length = bindingKeys.length;
IBinding[] result = new IBinding[length];
for (int i = 0; i < length; i++) {
result[i] = null;
if (this.compilationUnitResolver != null) {
result[i] = this.compilationUnitResolver.createBinding(bindingKeys[i]);
}
}
return result;
}
}