content: /*
   * Licensed to the Apache Software Foundation (ASF) under one or more
   * contributor license agreements.  See the NOTICE file distributed with
   * this work for additional information regarding copyright ownership.
   * The ASF licenses this file to You 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.apache.camel.language.ognl;
  
  import ognl.ClassResolver;
  import ognl.Ognl;
  import ognl.OgnlContext;
  import ognl.OgnlException;
  import org.apache.camel.Exchange;
  import org.apache.camel.ExpressionEvaluationException;
  import org.apache.camel.ExpressionIllegalSyntaxException;
  import org.apache.camel.support.ExpressionSupport;
  
  /**
   * An OGNL {@link org.apache.camel.Expression}
   */
  public class OgnlExpression extends ExpressionSupport {
  
      private final String expressionString;
      private final Class<?> type;
      private Object expression;
  
      public OgnlExpression(String expressionString, Class<?> type) {
          this.expressionString = expressionString;
          this.type = type;
          try {
              this.expression = Ognl.parseExpression(expressionString);
          } catch (OgnlException e) {
              throw new ExpressionIllegalSyntaxException(expressionString, e);
          }
      }
  
      public static OgnlExpression ognl(String expression) {
          return new OgnlExpression(expression, Object.class);
      }
  
      @Override
      public <T> T evaluate(Exchange exchange, Class<T> tClass) {
          ClassResolver cr = new CamelClassResolver(exchange.getContext().getClassResolver());
          RootObject root = new RootObject(exchange);
          OgnlContext oglContext = Ognl.createDefaultContext(root, cr);
          try {
              Object value = Ognl.getValue(expression, oglContext, root);
              return exchange.getContext().getTypeConverter().convertTo(tClass, value);
          } catch (OgnlException e) {
              throw new ExpressionEvaluationException(this, exchange, e);
          }
      }
  
      public Class<?> getType() {
          return type;
      }
  
      @Override
      protected String assertionFailureMessage(Exchange exchange) {
          return expressionString;
      }
  
      @Override
      public String toString() {
          return "OGNL[" + expressionString + "]";
      }
  }
  