/*
* Copyright 2009-2011 The MyBatis Team
*
* 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.founderdpt.comm.xworld.util.config.builder;
import java.io.StringReader;
import java.util.Map;
import java.util.concurrent.ConcurrentHashMap;
import ognl.ExpressionSyntaxException;
import ognl.Node;
import ognl.Ognl;
import ognl.OgnlException;
import ognl.OgnlParser;
import ognl.ParseException;
import ognl.TokenMgrError;
/**
*
* Caches OGNL parsed expressions.
* Have a look at http://code.google.com/p/mybatis/issues/detail?id=342
*
*/
public class OgnlCache {
private static final Map<String, ognl.Node> expressionCache = new ConcurrentHashMap<String, ognl.Node>();
public static Object getValue(String expression, Object root) throws OgnlException {
return Ognl.getValue(parseExpression(expression), root);
}
private static Object parseExpression(String expression) throws OgnlException {
try {
Node node = expressionCache.get(expression);
if (node == null) {
node = new OgnlParser(new StringReader(expression)).topLevelExpression();
expressionCache.put(expression, node);
}
return node;
} catch (ParseException e) {
throw new ExpressionSyntaxException(expression, e);
} catch (TokenMgrError e) {
throw new ExpressionSyntaxException(expression, e);
}
}
}