code: /*
   * 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.
   */
  /*
   * $Id$
   */
  
  package org.apache.xalan.xsltc.compiler;
  
  import java.util.Vector;
  
  import org.apache.bcel.generic.ALOAD;
  import org.apache.bcel.generic.ASTORE;
  import org.apache.bcel.generic.ConstantPoolGen;
  import org.apache.bcel.generic.GETFIELD;
  import org.apache.bcel.generic.INVOKESTATIC;
  import org.apache.bcel.generic.INVOKEVIRTUAL;
  import org.apache.bcel.generic.InstructionList;
  import org.apache.bcel.generic.LocalVariableGen;
  import org.apache.bcel.generic.PUSH;
  import org.apache.xalan.xsltc.compiler.util.ClassGenerator;
  import org.apache.xalan.xsltc.compiler.util.ErrorMsg;
  import org.apache.xalan.xsltc.compiler.util.MethodGenerator;
  import org.apache.xalan.xsltc.compiler.util.Type;
  import org.apache.xalan.xsltc.compiler.util.TypeCheckError;
  import org.apache.xalan.xsltc.compiler.util.Util;
  
  import org.apache.xml.serializer.ElemDesc;
  import org.apache.xml.serializer.SerializationHandler;
  import org.apache.xml.utils.XML11Char;
  
  /**
   * @author Jacek Ambroziak
   * @author Santiago Pericas-Geertsen
   * @author Morten Jorgensen
   * @author Erwin Bolwidt <ejb@klomp.org>
   * @author Gunnlaugur Briem <gthb@dimon.is>
   */
  final class XslAttribute extends Instruction {
  
      private String _prefix;
      private AttributeValue _name; 	// name treated as AVT (7.1.3)
      private AttributeValueTemplate _namespace = null;
      private boolean _ignore = false;
      private boolean _isLiteral = false;  // specified name is not AVT  
  
      /**
       * Returns the name of the attribute
       */
      public AttributeValue getName() {
  	return _name;
      }
  
      /**
       * Displays the contents of the attribute
       */
      public void display(int indent) {
  	indent(indent);
  	Util.println("Attribute " + _name);
  	displayContents(indent + IndentIncrement);
      }
  		
      /**
       * Parses the attribute's contents. Special care taken for namespaces.
       */
      public void parseContents(Parser parser) {
  	boolean generated = false;
  	final SymbolTable stable = parser.getSymbolTable();
  
  	String name = getAttribute("name");
  	String namespace = getAttribute("namespace");
  	QName qname = parser.getQName(name, false);
  	final String prefix = qname.getPrefix();
  
          if (((prefix != null) && (prefix.equals(XMLNS_PREFIX)))||(name.equals(XMLNS_PREFIX))) {
  	    reportError(this, parser, ErrorMsg.ILLEGAL_ATTR_NAME_ERR, name);
  	    return;
  	}
    
          _isLiteral = Util.isLiteral(name);
          if (_isLiteral) {
              if (!XML11Char.isXML11ValidQName(name)) {
                  reportError(this, parser, ErrorMsg.ILLEGAL_ATTR_NAME_ERR, name);
                  return;
              }
          }
  
  	// Ignore attribute if preceeded by some other type of element
  	final SyntaxTreeNode parent = getParent();
  	final Vector siblings = parent.getContents();
  	for (int i = 0; i < parent.elementCount(); i++) {
  	    SyntaxTreeNode item = (SyntaxTreeNode)siblings.elementAt(i);
  	    if (item == this) break;
  
  	    // These three objects result in one or more attribute output
  	    if (item instanceof XslAttribute) continue;
  	    if (item instanceof UseAttributeSets) continue;
  	    if (item instanceof LiteralAttribute) continue;
  	    if (item instanceof Text) continue;
  
  	    // These objects _can_ result in one or more attribute
  	    // The output handler will generate an error if not (at runtime)
  	    if (item instanceof If) continue;
  	    if (item instanceof Choose) continue;
   	    if (item instanceof CopyOf) continue;
   	    if (item instanceof VariableBase) continue;
  
  	    // Report warning but do not ignore attribute
  	    reportWarning(this, parser, ErrorMsg.STRAY_ATTRIBUTE_ERR, name);
  	}
  
  	// Get namespace from namespace attribute?
  	if (namespace != null && namespace != Constants.EMPTYSTRING) {
  	    _prefix = lookupPrefix(namespace);
  	    _namespace = new AttributeValueTemplate(namespace, parser, this);
  	}
  	// Get namespace from prefix in name attribute?
  	else if (prefix != null && prefix != Constants.EMPTYSTRING) {
  	    _prefix = prefix;
  	    namespace = lookupNamespace(prefix);
  	    if (namespace != null) {
  		_namespace = new AttributeValueTemplate(namespace, parser, this);
  	    }
  	}
  	
  	// Common handling for namespaces:
  	if (_namespace != null) {
  	    // Generate prefix if we have none
  	    if (_prefix == null || _prefix == Constants.EMPTYSTRING) {
  		if (prefix != null) {
  		    _prefix = prefix;
  		}
  		else {
  		    _prefix = stable.generateNamespacePrefix();
  		    generated = true;
  		}
  	    }
  	    else if (prefix != null && !prefix.equals(_prefix)) {
  		_prefix = prefix;
  	    }
  
  	    name = _prefix + ":" + qname.getLocalPart();
  
  	    /*
  	     * TODO: The namespace URI must be passed to the parent 
  	     * element but we don't yet know what the actual URI is 
  	     * (as we only know it as an attribute value template). 
  	     */
  	    if ((parent instanceof LiteralElement) && (!generated)) {
  		((LiteralElement)parent).registerNamespace(_prefix,
  							   namespace,
  							   stable, false);
  	    }
  	}
  
  	if (parent instanceof LiteralElement) {
  	    ((LiteralElement)parent).addAttribute(this);
  	}
  
  	_name = AttributeValue.create(this, name, parser);
  	parseChildren(parser);
      }
  	
      public Type typeCheck(SymbolTable stable) throws TypeCheckError {
  	if (!_ignore) {
  	    _name.typeCheck(stable);
  	    if (_namespace != null) {
  		_namespace.typeCheck(stable);
  	    }
  	    typeCheckContents(stable);
  	}
  	return Type.Void;
      }
  
      /**
       *
       */
      public void translate(ClassGenerator classGen, MethodGenerator methodGen) {
  	final ConstantPoolGen cpg = classGen.getConstantPool();
  	final InstructionList il = methodGen.getInstructionList();
  
  	if (_ignore) return;
  	_ignore = true;    
  
  	// Compile code that emits any needed namespace declaration
  	if (_namespace != null) {
  	    // public void attribute(final String name, final String value)
  	    il.append(methodGen.loadHandler());
  	    il.append(new PUSH(cpg,_prefix));
  	    _namespace.translate(classGen,methodGen);
  	    il.append(methodGen.namespace());
  	}
      
          if (!_isLiteral) {
              // if the qname is an AVT, then the qname has to be checked at runtime if it is a valid qname
              LocalVariableGen nameValue =
                      methodGen.addLocalVariable2("nameValue",
                                                  Util.getJCRefType(STRING_SIG),
                                                  null);
                      
              // store the name into a variable first so _name.translate only needs to be called once  
              _name.translate(classGen, methodGen);
              nameValue.setStart(il.append(new ASTORE(nameValue.getIndex())));
              il.append(new ALOAD(nameValue.getIndex()));
              
              // call checkQName if the name is an AVT
              final int check = cpg.addMethodref(BASIS_LIBRARY_CLASS, "checkAttribQName",
                              "("
                              +STRING_SIG
                              +")V");                 
              il.append(new INVOKESTATIC(check));
              
              // Save the current handler base on the stack
              il.append(methodGen.loadHandler());
              il.append(DUP);     // first arg to "attributes" call            
              
              // load name value again    
              nameValue.setEnd(il.append(new ALOAD(nameValue.getIndex())));            
          } else {    
              // Save the current handler base on the stack
              il.append(methodGen.loadHandler());
              il.append(DUP);     // first arg to "attributes" call
              
              // Push attribute name
              _name.translate(classGen, methodGen);// 2nd arg
      
          }
  
  	// Push attribute value - shortcut for literal strings
  	if ((elementCount() == 1) && (elementAt(0) instanceof Text)) {
  	    il.append(new PUSH(cpg, ((Text)elementAt(0)).getText()));
  	}
  	else {
  	    il.append(classGen.loadTranslet());
  	    il.append(new GETFIELD(cpg.addFieldref(TRANSLET_CLASS,
  						   "stringValueHandler",
  						   STRING_VALUE_HANDLER_SIG)));
  	    il.append(DUP);
  	    il.append(methodGen.storeHandler());
  	    // translate contents with substituted handler
  	    translateContents(classGen, methodGen);
  	    // get String out of the handler
  	    il.append(new INVOKEVIRTUAL(cpg.addMethodref(STRING_VALUE_HANDLER,
  							 "getValue",
  							 "()" + STRING_SIG)));
  	}
  
  	SyntaxTreeNode parent = getParent();
  	if (parent instanceof LiteralElement
  	    && ((LiteralElement)parent).allAttributesUnique()) {
              int flags = 0;
  	    ElemDesc elemDesc = ((LiteralElement)parent).getElemDesc();
  	    
  	    // Set the HTML flags
  	    if (elemDesc != null && _name instanceof SimpleAttributeValue) {
  	    	String attrName = ((SimpleAttributeValue)_name).toString();
  	    	if (elemDesc.isAttrFlagSet(attrName, ElemDesc.ATTREMPTY)) {
  	    	    flags = flags | SerializationHandler.HTML_ATTREMPTY;
  	    	}
  	    	else if (elemDesc.isAttrFlagSet(attrName, ElemDesc.ATTRURL)) {
  	    	    flags = flags | SerializationHandler.HTML_ATTRURL;
  	    	}
  	    }
  	    il.append(new PUSH(cpg, flags));
  	    il.append(methodGen.uniqueAttribute());    
  	}
  	else {
  	    // call "attribute"
  	    il.append(methodGen.attribute());
  	}
              
  	// Restore old handler base from stack
  	il.append(methodGen.storeHandler());
      
  
          
      }
  
  }
  