| /* |
| * Copyright (C) 2012 The Android Open Source Project |
| * |
| * Licensed under the Eclipse Public License, Version 1.0 (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.eclipse.org/org/documents/epl-v10.php |
| * |
| * 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 com.android.ide.eclipse.adt.internal.wizards.templates; |
| |
| import static com.android.tools.lint.detector.api.LintUtils.assertionsEnabled; |
| |
| import com.android.annotations.NonNull; |
| import com.android.annotations.Nullable; |
| import com.android.ide.eclipse.adt.AdtPlugin; |
| |
| import freemarker.cache.TemplateLoader; |
| import freemarker.template.Configuration; |
| import freemarker.template.DefaultObjectWrapper; |
| import freemarker.template.Template; |
| |
| import java.io.IOException; |
| import java.io.Reader; |
| import java.io.StringReader; |
| import java.io.StringWriter; |
| import java.util.List; |
| import java.util.Map; |
| |
| /** |
| * A template handler which can evaluate simple strings. Used to evaluate |
| * parameter constraints during UI wizard value editing. |
| * <p> |
| * Unlike the more general {@link TemplateHandler} which is used to instantiate |
| * full template files (from resources, merging into existing files etc) this |
| * evaluator supports only simple strings, referencing only values from the |
| * provided map (and builtin functions). |
| */ |
| class StringEvaluator implements TemplateLoader { |
| private Map<String, Object> mParameters; |
| private Configuration mFreemarker; |
| private String mCurrentExpression; |
| |
| StringEvaluator() { |
| mParameters = TemplateHandler.createBuiltinMap(); |
| |
| mFreemarker = new Configuration(); |
| mFreemarker.setObjectWrapper(new DefaultObjectWrapper()); |
| mFreemarker.setTemplateLoader(this); |
| } |
| |
| /** Evaluates the given expression, with the given set of parameters */ |
| @Nullable |
| String evaluate(@NonNull String expression, @NonNull List<Parameter> parameters) { |
| // Render the instruction list template. |
| for (Parameter parameter : parameters) { |
| mParameters.put(parameter.id, parameter.value); |
| } |
| try { |
| mCurrentExpression = expression; |
| Template inputsTemplate = mFreemarker.getTemplate(expression); |
| StringWriter out = new StringWriter(); |
| inputsTemplate.process(mParameters, out); |
| out.flush(); |
| return out.toString(); |
| } catch (Exception e) { |
| if (assertionsEnabled()) { |
| AdtPlugin.log(e, null); |
| } |
| return null; |
| } |
| } |
| |
| // ---- Implements TemplateLoader ---- |
| |
| @Override |
| public Object findTemplateSource(String name) throws IOException { |
| return mCurrentExpression; |
| } |
| |
| @Override |
| public long getLastModified(Object templateSource) { |
| return 0; |
| } |
| |
| @Override |
| public Reader getReader(Object templateSource, String encoding) throws IOException { |
| return new StringReader(mCurrentExpression); |
| } |
| |
| @Override |
| public void closeTemplateSource(Object templateSource) throws IOException { |
| } |
| } |