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 * reserved comment block
 * DO NOT REMOVE OR ALTER!
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/*
 * 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 java.util.Enumeration;

import com.sun.org.apache.bcel.internal.generic.ConstantPoolGen;
import com.sun.org.apache.bcel.internal.generic.INVOKESPECIAL;
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.NEW;
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;
import com.sun.org.apache.xalan.internal.xsltc.compiler.util.Util;

final class ApplyImports extends Instruction {

    private QName      _modeName;
    private int        _precedence;

    public void display(int indent) {
        indent(indent);
        Util.println("ApplyTemplates");
        indent(indent + IndentIncrement);
        if (_modeName != null) {
            indent(indent + IndentIncrement);
            Util.println("mode " + _modeName);
        }
    }

    
Returns true if this  element has parameters
/**
     * Returns true if this <xsl:apply-imports/> element has parameters
     */
    public boolean hasWithParams() {
        return hasContents();
    }

    
Determine the lowest import precedence for any stylesheet imported
or included by the stylesheet in which this 
element occured. The templates that are imported by the stylesheet in
which this element occured will all have higher import precedence than
the integer returned by this method.
/**
     * Determine the lowest import precedence for any stylesheet imported
     * or included by the stylesheet in which this <xsl:apply-imports/>
     * element occured. The templates that are imported by the stylesheet in
     * which this element occured will all have higher import precedence than
     * the integer returned by this method.
     */
    private int getMinPrecedence(int max) {
        // Move to root of include tree
        Stylesheet includeRoot = getStylesheet();
        while (includeRoot._includedFrom != null) {
            includeRoot = includeRoot._includedFrom;
        }

        return includeRoot.getMinimumDescendantPrecedence();
    }

    
Parse the attributes and contents of an  element.
/**
     * Parse the attributes and contents of an <xsl:apply-imports/> element.
     */
    public void parseContents(Parser parser) {
        // Indicate to the top-level stylesheet that all templates must be
        // compiled into separate methods.
        Stylesheet stylesheet = getStylesheet();
        stylesheet.setTemplateInlining(false);

        // Get the mode we are currently in (might not be any)
        Template template = getTemplate();
        _modeName = template.getModeName();
        _precedence = template.getImportPrecedence();

        // Get the method name for <xsl:apply-imports/> in this mode
        stylesheet = parser.getTopLevelStylesheet();

        parseChildren(parser);  // with-params
    }

    
Type-check the attributes/contents of an  element.
/**
     * Type-check the attributes/contents of an <xsl:apply-imports/> element.
     */
    public Type typeCheck(SymbolTable stable) throws TypeCheckError {
        typeCheckContents(stable);              // with-params
        return Type.Void;
    }

    
Translate call-template. A parameter frame is pushed only if
some template in the stylesheet uses parameters.
/**
     * Translate call-template. A parameter frame is pushed only if
     * some template in the stylesheet uses parameters.
     */
    public void translate(ClassGenerator classGen, MethodGenerator methodGen) {
        final Stylesheet stylesheet = classGen.getStylesheet();
        final ConstantPoolGen cpg = classGen.getConstantPool();
        final InstructionList il = methodGen.getInstructionList();
        final int current = methodGen.getLocalIndex("current");

        // Push the arguments that are passed to applyTemplates()
        il.append(classGen.loadTranslet());
        il.append(methodGen.loadDOM());
    il.append(methodGen.loadIterator());
        il.append(methodGen.loadHandler());
    il.append(methodGen.loadCurrentNode());

        // Push a new parameter frame in case imported template might expect
        // parameters.  The apply-imports has nothing that it can pass.
        if (stylesheet.hasLocalParams()) {
            il.append(classGen.loadTranslet());
            final int pushFrame = cpg.addMethodref(TRANSLET_CLASS,
                                                   PUSH_PARAM_FRAME,
                                                   PUSH_PARAM_FRAME_SIG);
            il.append(new INVOKEVIRTUAL(pushFrame));
        }

        // Get the [min,max> precedence of all templates imported under the
        // current stylesheet
        final int maxPrecedence = _precedence;
        final int minPrecedence = getMinPrecedence(maxPrecedence);
        final Mode mode = stylesheet.getMode(_modeName);

        // Get name of appropriate apply-templates function for this
        // xsl:apply-imports instruction
        String functionName = mode.functionName(minPrecedence, maxPrecedence);

        // Construct the translet class-name and the signature of the method
        final String className = classGen.getStylesheet().getClassName();
        final String signature = classGen.getApplyTemplatesSigForImport();
        final int applyTemplates = cpg.addMethodref(className,
                                                    functionName,
                                                    signature);
        il.append(new INVOKEVIRTUAL(applyTemplates));

        // Pop any parameter frame that was pushed above.
        if (stylesheet.hasLocalParams()) {
            il.append(classGen.loadTranslet());
            final int pushFrame = cpg.addMethodref(TRANSLET_CLASS,
                                                   POP_PARAM_FRAME,
                                                   POP_PARAM_FRAME_SIG);
            il.append(new INVOKEVIRTUAL(pushFrame));
        }
    }

}