/*

 * reserved comment block

 * DO NOT REMOVE OR ALTER!

 */

/*

 * 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 com.sun.org.apache.xpath.internal.functions;

import com.sun.org.apache.xalan.internal.res.XSLMessages;

import com.sun.org.apache.xpath.internal.XPathContext;

import com.sun.org.apache.xpath.internal.objects.XObject;

import com.sun.org.apache.xpath.internal.objects.XString;

/**

 * Execute the Concat() function.

 * @xsl.usage advanced

 */

public class FuncConcat extends FunctionMultiArgs

{

    static final long serialVersionUID = 1737228885202314413L;

  /**

   * Execute the function.  The function must return

   * a valid object.

   * @param xctxt The current execution context.

   * @return A valid XObject.

   *

   * @throws javax.xml.transform.TransformerException

   */

  public XObject execute(XPathContext xctxt) throws javax.xml.transform.TransformerException

  {

    StringBuffer sb = new StringBuffer();

    // Compiler says we must have at least two arguments.

    sb.append(m_arg0.execute(xctxt).str());

    sb.append(m_arg1.execute(xctxt).str());

    if (null != m_arg2)

      sb.append(m_arg2.execute(xctxt).str());

    if (null != m_args)

    {

      for (int i = 0; i < m_args.length; i++)

      {

        sb.append(m_args[i].execute(xctxt).str());

      }

    }

    return new XString(sb.toString());

  }

  /**

   * Check that the number of arguments passed to this function is correct.

   *

   *

   * @param argNum The number of arguments that is being passed to the function.

   *

   * @throws WrongNumberArgsException

   */

  public void checkNumberArgs(int argNum) throws WrongNumberArgsException

  {

    if (argNum < 2)

      reportWrongNumberArgs();

  }

  /**

   * Constructs and throws a WrongNumberArgException with the appropriate

   * message for this function object.

   *

   * @throws WrongNumberArgsException

   */

  protected void reportWrongNumberArgs() throws WrongNumberArgsException {

      throw new WrongNumberArgsException(XSLMessages.createXPATHMessage("gtone", null));

  }

}