/*

 * 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.

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package com.sun.org.apache.xalan.internal.xsltc.compiler;

import com.sun.org.apache.bcel.internal.generic.ConstantPoolGen;

import com.sun.org.apache.bcel.internal.generic.GOTO;

import com.sun.org.apache.bcel.internal.generic.IFNE;

import com.sun.org.apache.bcel.internal.generic.INVOKEINTERFACE;

import com.sun.org.apache.bcel.internal.generic.INVOKEVIRTUAL;

import com.sun.org.apache.bcel.internal.generic.InstructionList;

import com.sun.org.apache.bcel.internal.generic.PUSH;

import com.sun.org.apache.xalan.internal.xsltc.compiler.util.ClassGenerator;

import com.sun.org.apache.xalan.internal.xsltc.compiler.util.MethodGenerator;

import com.sun.org.apache.xalan.internal.xsltc.compiler.util.Type;

import com.sun.org.apache.xalan.internal.xsltc.compiler.util.TypeCheckError;

/**

 * @author Jacek Ambroziak

 * @author Santiago Pericas-Geertsen

 */

abstract class IdKeyPattern extends LocationPathPattern {

    protected RelativePathPattern _left = null;;

    private String _index = null;

    private String _value = null;;

    public IdKeyPattern(String index, String value) {

        _index = index;

        _value = value;

    }

    public String getIndexName() {

        return(_index);

    }

    public Type typeCheck(SymbolTable stable) throws TypeCheckError {

        return Type.NodeSet;

    }

    public boolean isWildcard() {

        return false;

    }

    public void setLeft(RelativePathPattern left) {

        _left = left;

    }

    public StepPattern getKernelPattern() {

        return(null);

    }

    public void reduceKernelPattern() { }

    public String toString() {

        return "id/keyPattern(" + _index + ", " + _value + ')';

    }

    /**

     * This method is called when the constructor is compiled in

     * Stylesheet.compileConstructor() and not as the syntax tree is traversed.

     */

    public void translate(ClassGenerator classGen,

                          MethodGenerator methodGen) {

        final ConstantPoolGen cpg = classGen.getConstantPool();

        final InstructionList il = methodGen.getInstructionList();

        // Returns the KeyIndex object of a given name

        final int getKeyIndex = cpg.addMethodref(TRANSLET_CLASS,

                                                 "getKeyIndex",

                                                 "(Ljava/lang/String;)"+

                                                 KEY_INDEX_SIG);

        // Initialises a KeyIndex to return nodes with specific values

        final int lookupId = cpg.addMethodref(KEY_INDEX_CLASS,

                                              "containsID",

                                              "(ILjava/lang/Object;)I");

        final int lookupKey = cpg.addMethodref(KEY_INDEX_CLASS,

                                               "containsKey",

                                               "(ILjava/lang/Object;)I");

        final int getNodeIdent = cpg.addInterfaceMethodref(DOM_INTF,

                                                           "getNodeIdent",

                                                           "(I)"+NODE_SIG);

        // Call getKeyIndex in AbstractTranslet with the name of the key

        // to get the index for this key (which is also a node iterator).

        il.append(classGen.loadTranslet());

        il.append(new PUSH(cpg,_index));

        il.append(new INVOKEVIRTUAL(getKeyIndex));

        // Now use the value in the second argument to determine what nodes

        // the iterator should return.

        il.append(SWAP);

        il.append(new PUSH(cpg,_value));

        if (this instanceof IdPattern)

        {

            il.append(new INVOKEVIRTUAL(lookupId));

        }

        else

        {

            il.append(new INVOKEVIRTUAL(lookupKey));

        }

        _trueList.add(il.append(new IFNE(null)));

        _falseList.add(il.append(new GOTO(null)));

    }

}