/*
* =============================================================================
*
* Copyright (c) 2011-2014, The THYMELEAF team (http://www.thymeleaf.org)
*
* 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 org.thymeleaf.standard.expression;
import java.io.Serializable;
import org.thymeleaf.Configuration;
import org.thymeleaf.context.IProcessingContext;
import org.thymeleaf.exceptions.TemplateProcessingException;
import org.thymeleaf.util.Validate;
/**
*
* @author Daniel Fernández
*
* @since 1.1
*
*/
public abstract class Expression implements IStandardExpression, Serializable {
private static final long serialVersionUID = 1608378943284014151L;
public static final char PARSING_PLACEHOLDER_CHAR = '\u00A7';
public static final char NESTING_START_CHAR = '(';
public static final char NESTING_END_CHAR = ')';
protected Expression() {
super();
}
public abstract String getStringRepresentation();
@Override
public String toString() {
return getStringRepresentation();
}
static Expression parse(final String input) {
Validate.notNull(input, "Input cannot be null");
/*
* PHASE 01: Decomposition (including unnesting parenthesis)
*/
final ExpressionParsingState decomposition =
ExpressionParsingUtil.decompose(input, ExpressionParsingDecompositionConfig.DECOMPOSE_ALL_AND_UNNEST);
if (decomposition == null) {
return null;
}
/*
* PHASE 02: Composition
*/
final ExpressionParsingState result = ExpressionParsingUtil.compose(decomposition);
if (result == null || !result.hasExpressionAt(0)) {
return null;
}
return result.get(0).getExpression();
}
static Object execute(final Configuration configuration, final IProcessingContext processingContext,
final Expression expression, final IStandardVariableExpressionEvaluator expressionEvaluator,
final StandardExpressionExecutionContext expContext) {
if (expression instanceof SimpleExpression) {
return SimpleExpression.executeSimple(
configuration, processingContext, (SimpleExpression)expression, expressionEvaluator, expContext);
}
if (expression instanceof ComplexExpression) {
return ComplexExpression.executeComplex(
configuration, processingContext, (ComplexExpression)expression, expContext);
}
throw new TemplateProcessingException("Unrecognized expression: " + expression.getClass().getName());
}
public Object execute(final Configuration configuration, final IProcessingContext processingContext) {
return execute(configuration, processingContext, StandardExpressionExecutionContext.NORMAL);
}
public Object execute(final Configuration configuration, final IProcessingContext processingContext,
final StandardExpressionExecutionContext expContext) {
Validate.notNull(configuration, "Configuration cannot be null");
Validate.notNull(processingContext, "Processing context cannot be null");
final IStandardVariableExpressionEvaluator variableExpressionEvaluator =
StandardExpressions.getVariableExpressionEvaluator(configuration);
final Object result = execute(configuration, processingContext, this, variableExpressionEvaluator, expContext);
return LiteralValue.unwrap(result);
}
}