001    /**
002     * Licensed to the Apache Software Foundation (ASF) under one or more
003     * contributor license agreements.  See the NOTICE file distributed with
004     * this work for additional information regarding copyright ownership.
005     * The ASF licenses this file to You under the Apache License, Version 2.0
006     * (the "License"); you may not use this file except in compliance with
007     * the License.  You may obtain a copy of the License at
008     *
009     *      http://www.apache.org/licenses/LICENSE-2.0
010     *
011     * Unless required by applicable law or agreed to in writing, software
012     * distributed under the License is distributed on an "AS IS" BASIS,
013     * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
014     * See the License for the specific language governing permissions and
015     * limitations under the License.
016     */
017    package org.apache.camel.language.simple.ast;
018    
019    import org.apache.camel.Expression;
020    import org.apache.camel.builder.ExpressionBuilder;
021    import org.apache.camel.language.simple.types.SimpleToken;
022    
023    /**
024     * Starts a block enclosed by single quotes
025     */
026    public class SingleQuoteStart extends BaseSimpleNode implements BlockStart {
027    
028        private final CompositeNodes block;
029    
030        public SingleQuoteStart(SimpleToken token) {
031            super(token);
032            this.block = new CompositeNodes(token);
033        }
034    
035        @Override
036        public String toString() {
037            // output a nice toString so it makes debugging easier as we can see the entire block
038            return "'" + block + "'";
039        }
040    
041        @Override
042        public Expression createExpression(String expression) {
043            Expression answer = null;
044            if (block != null) {
045                answer = block.createExpression(expression);
046            }
047            if (answer == null) {
048                // there quoted literal is empty
049                answer = ExpressionBuilder.constantExpression("");
050            }
051            return answer;
052        }
053    
054        @Override
055        public boolean acceptAndAddNode(SimpleNode node) {
056            block.addChild(node);
057            return true;
058        }
059    
060    }