| /******************************************************************************* |
| * Copyright (c) 2000, 2003 IBM Corporation and others. |
| * All rights reserved. This program and the accompanying materials |
| * are made available under the terms of the Common Public License v1.0 |
| * which accompanies this distribution, and is available at |
| * http://www.eclipse.org/legal/cpl-v10.html |
| * |
| * Contributors: |
| * IBM Corporation - initial API and implementation |
| *******************************************************************************/ |
| package org.eclipse.jface.text.templates; |
| |
| import java.util.HashMap; |
| import java.util.Map; |
| |
| import org.eclipse.jface.text.BadLocationException; |
| |
| /** |
| * Provides the context for a <code>Template</code> being resolved. Keeps track |
| * of resolved variables. |
| * |
| * @since 3.0 |
| */ |
| public abstract class TemplateContext { |
| |
| /** The context type of this context */ |
| private final ContextType fContextType; |
| /** Additional variables. */ |
| private final Map fVariables= new HashMap(); |
| /** A flag to indicate that the context should not be modified. */ |
| private boolean fReadOnly; |
| |
| /** |
| * Creates a template context of a particular context type. |
| * |
| * @param contextType the context type of this context |
| */ |
| protected TemplateContext(ContextType contextType) { |
| fContextType= contextType; |
| fReadOnly= true; |
| } |
| |
| /** |
| * Returns the context type of this context. |
| * |
| * @return the context type of this context |
| */ |
| public ContextType getContextType() { |
| return fContextType; |
| } |
| |
| /** |
| * Sets or clears the read-only flag. |
| * |
| * @param readOnly the new read-only state |
| */ |
| public void setReadOnly(boolean readOnly) { |
| fReadOnly= readOnly; |
| } |
| |
| /** |
| * Returns <code>true</code> if the receiver is read-only, <code>false</code> otherwise. |
| * |
| * @return <code>true</code> if the receiver is read-only, <code>false</code> otherwise |
| */ |
| public boolean isReadOnly() { |
| return fReadOnly; |
| } |
| |
| /** |
| * Defines the value of a variable. |
| * |
| * @param name the name of the variable |
| * @param value the value of the variable, <code>null</code> to undefine a variable |
| */ |
| public void setVariable(String name, String value) { |
| fVariables.put(name, value); |
| } |
| |
| /** |
| * Returns the value of a defined variable. |
| * |
| * @param name the name of the variable |
| * @return returns the value of the variable, <code>null</code> if the variable was not defined |
| */ |
| public String getVariable(String name) { |
| return (String) fVariables.get(name); |
| } |
| |
| /** |
| * Evaluates the template in this context and returns a template buffer. |
| * <p> |
| * Evaluation means translating the template into a <code>TemplateBuffer</code>, |
| * resolving the defined variables in this context and possibly formatting |
| * the resolved buffer.</p> |
| * |
| * @param template the template to evaluate |
| * @return returns the buffer with the evaluated template or <code>null</code> if the buffer could not be created |
| * @throws BadLocationException if evaluation fails due to concurrently changed documents etc. |
| * @throws TemplateException if the template specification is not valid |
| */ |
| public abstract TemplateBuffer evaluate(Template template) throws BadLocationException, TemplateException; |
| |
| /** |
| * Tests if the specified template can be evaluated in this context. |
| * <p>Examples are templates defined for a different context (e.g. a javadoc |
| * template cannot be evaluated in Java context).</p> |
| * |
| * @param template the <code>Template</code> to check |
| * @return <code>true</code> if <code>template</code> can be evaluated |
| * in this context, <code>false</code> otherwise |
| */ |
| public abstract boolean canEvaluate(Template template); |
| |
| } |