1 /*
2  * Licensed to the Apache Software Foundation (ASF) under one
3  * or more contributor license agreements. See the NOTICE file
4  * distributed with this work for additional information
5  * regarding copyright ownership. The ASF licenses this file
6  * to you under the Apache License, Version 2.0 (the  "License");
7  * you may not use this file except in compliance with the License.
8  * You may obtain a copy of the License at
9  *
10  *     http://www.apache.org/licenses/LICENSE-2.0
11  *
12  * Unless required by applicable law or agreed to in writing, software
13  * distributed under the License is distributed on an "AS IS" BASIS,
14  * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
15  * See the License for the specific language governing permissions and
16  * limitations under the License.
17  */
18 /*
19  * $Id: FuncConcat.java 468655 2006-10-28 07:12:06Z minchau $
20  */
21 package org.apache.xpath.functions;
22 
23 import org.apache.xalan.res.XSLMessages;
24 import org.apache.xpath.XPathContext;
25 import org.apache.xpath.objects.XObject;
26 import org.apache.xpath.objects.XString;
27 
28 /**
29  * Execute the Concat() function.
30  * @xsl.usage advanced
31  */
32 public class FuncConcat extends FunctionMultiArgs
33 {
34     static final long serialVersionUID = 1737228885202314413L;
35 
36   /**
37    * Execute the function.  The function must return
38    * a valid object.
39    * @param xctxt The current execution context.
40    * @return A valid XObject.
41    *
42    * @throws javax.xml.transform.TransformerException
43    */
execute(XPathContext xctxt)44   public XObject execute(XPathContext xctxt) throws javax.xml.transform.TransformerException
45   {
46 
47     StringBuffer sb = new StringBuffer();
48 
49     // Compiler says we must have at least two arguments.
50     sb.append(m_arg0.execute(xctxt).str());
51     sb.append(m_arg1.execute(xctxt).str());
52 
53     if (null != m_arg2)
54       sb.append(m_arg2.execute(xctxt).str());
55 
56     if (null != m_args)
57     {
58       for (int i = 0; i < m_args.length; i++)
59       {
60         sb.append(m_args[i].execute(xctxt).str());
61       }
62     }
63 
64     return new XString(sb.toString());
65   }
66 
67   /**
68    * Check that the number of arguments passed to this function is correct.
69    *
70    *
71    * @param argNum The number of arguments that is being passed to the function.
72    *
73    * @throws WrongNumberArgsException
74    */
checkNumberArgs(int argNum)75   public void checkNumberArgs(int argNum) throws WrongNumberArgsException
76   {
77     if (argNum < 2)
78       reportWrongNumberArgs();
79   }
80 
81   /**
82    * Constructs and throws a WrongNumberArgException with the appropriate
83    * message for this function object.
84    *
85    * @throws WrongNumberArgsException
86    */
reportWrongNumberArgs()87   protected void reportWrongNumberArgs() throws WrongNumberArgsException {
88       throw new WrongNumberArgsException(XSLMessages.createXPATHMessage("gtone", null));
89   }
90 }
91