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This OSGi bundle wraps ${pkgArtifactId} ${pkgVersion} jar file.
/*
* Copyright 2009 Google Inc.
*
* Licensed under the Apache License, Version 2.0 (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.apache.org/licenses/LICENSE-2.0
*
* 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.google.gwt.resources.css;
import com.google.gwt.core.ext.BadPropertyValueException;
import com.google.gwt.core.ext.ConfigurationProperty;
import com.google.gwt.core.ext.PropertyOracle;
import com.google.gwt.core.ext.SelectionProperty;
import com.google.gwt.core.ext.TreeLogger;
import com.google.gwt.resources.css.ast.Context;
import com.google.gwt.resources.css.ast.CssCompilerException;
import com.google.gwt.resources.css.ast.CssIf;
import com.google.gwt.resources.css.ast.CssModVisitor;
import com.google.gwt.resources.css.ast.CssNode;
import java.util.Arrays;
/**
* Statically evaluates {@literal @if} rules.
*/
public class IfEvaluator extends CssModVisitor {
private final TreeLogger logger;
private final PropertyOracle oracle;
public IfEvaluator(TreeLogger logger, PropertyOracle oracle) {
this.logger = logger.branch(TreeLogger.DEBUG,
"Replacing property-based @if blocks");
this.oracle = oracle;
}
@Override
public void endVisit(CssIf x, Context ctx) {
if (x.getExpression() != null) {
// This gets taken care of by the runtime substitution visitor
} else {
try {
String propertyName = x.getPropertyName();
String propValue = null;
try {
SelectionProperty selProp = oracle.getSelectionProperty(logger,
propertyName);
propValue = selProp.getCurrentValue();
} catch (BadPropertyValueException e) {
ConfigurationProperty confProp = oracle.getConfigurationProperty(propertyName);
propValue = confProp.getValues().get(0);
}
/*
* If the deferred binding property's value is in the list of values in
* the @if rule, move the rules into the @if's context.
*/
if (Arrays.asList(x.getPropertyValues()).contains(propValue)
^ x.isNegated()) {
for (CssNode n : x.getNodes()) {
ctx.insertBefore(n);
}
} else {
// Otherwise, move the else block into the if statement's position
for (CssNode n : x.getElseNodes()) {
ctx.insertBefore(n);
}
}
// Always delete @if rules that we can statically evaluate
ctx.removeMe();
} catch (BadPropertyValueException e) {
logger.log(TreeLogger.ERROR, "Unable to evaluate @if block", e);
throw new CssCompilerException("Unable to parse CSS", e);
}
}
}
}