content: /*
   *  This file is part of AndroidIDE.
   *
   *  AndroidIDE is free software: you can redistribute it and/or modify
   *  it under the terms of the GNU General Public License as published by
   *  the Free Software Foundation, either version 3 of the License, or
   *  (at your option) any later version.
   *
   *  AndroidIDE is distributed in the hope that it will be useful,
   *  but WITHOUT ANY WARRANTY; without even the implied warranty of
   *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
   *  GNU General Public License for more details.
   *
   *  You should have received a copy of the GNU General Public License
   *   along with AndroidIDE.  If not, see <https://www.gnu.org/licenses/>.
   */
  
  /*
   * reserved comment block
   * DO NOT REMOVE OR ALTER!
   */
  /*
   * Copyright 2001-2004 The Apache Software Foundation.
   *
   * 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.
   */
  /*
   * $Id: ElementAvailableCall.java,v 1.2.4.1 2005/09/01 14:13:01 pvedula Exp $
   */
  
  package jaxp.sun.org.apache.xalan.internal.xsltc.compiler;
  
  import java.util.Vector;
  
  import jaxp.sun.org.apache.bcel.internal.generic.ConstantPoolGen;
  import jaxp.sun.org.apache.bcel.internal.generic.PUSH;
  import jaxp.sun.org.apache.xalan.internal.xsltc.compiler.util.ClassGenerator;
  import jaxp.sun.org.apache.xalan.internal.xsltc.compiler.util.ErrorMsg;
  import jaxp.sun.org.apache.xalan.internal.xsltc.compiler.util.MethodGenerator;
  import jaxp.sun.org.apache.xalan.internal.xsltc.compiler.util.Type;
  import jaxp.sun.org.apache.xalan.internal.xsltc.compiler.util.TypeCheckError;
  
  /**
   * @author Jacek Ambroziak
   * @author Santiago Pericas-Geertsen
   */
  final class ElementAvailableCall extends FunctionCall {
  
      public ElementAvailableCall(QName fname, Vector arguments) {
          super(fname, arguments);
      }
  
      /**
       * Force the argument to this function to be a literal string.
       */
      public Type typeCheck(SymbolTable stable) throws TypeCheckError {
          if (argument() instanceof LiteralExpr) {
              return _type = Type.Boolean;
          }
          ErrorMsg err = new ErrorMsg(ErrorMsg.NEED_LITERAL_ERR,
                                      "element-available", this);
          throw new TypeCheckError(err);
      }
  
      /**
       * Returns an object representing the compile-time evaluation
       * of an expression. We are only using this for function-available
       * and element-available at this time.
       */
      public Object evaluateAtCompileTime() {
          return getResult() ? Boolean.TRUE : Boolean.FALSE;
      }
  
      /**
       * Returns the result that this function will return
       */
      public boolean getResult() {
          try {
              final LiteralExpr arg = (LiteralExpr) argument();
              final String qname = arg.getValue();
              final int index = qname.indexOf(':');
              final String localName = (index > 0) ?
                  qname.substring(index + 1) : qname;
              return getParser().elementSupported(arg.getNamespace(),
                                                  localName);
          }
          catch (ClassCastException e) {
              return false;
          }
      }
  
      /**
       * Calls to 'element-available' are resolved at compile time since
       * the namespaces declared in the stylsheet are not available at run
       * time. Consequently, arguments to this function must be literals.
       */
      public void translate(ClassGenerator classGen, MethodGenerator methodGen) {
          final ConstantPoolGen cpg = classGen.getConstantPool();
          final boolean result = getResult();
          methodGen.getInstructionList().append(new PUSH(cpg, result));
      }
  }
  