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 * 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.
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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.GETSTATIC;
import com.sun.org.apache.bcel.internal.generic.INVOKEINTERFACE;
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.Util;

Author:
Jacek Ambroziak, Santiago Pericas-Geertsen, Morten Jorgensen/**
 * @author Jacek Ambroziak
 * @author Santiago Pericas-Geertsen
 * @author Morten Jorgensen
 */
final class Text extends Instruction {

    private String _text;
    private boolean _escaping = true;
    private boolean _ignore = false;
    private boolean _textElement = false;

    
Create a blank Text syntax tree node.
/**
     * Create a blank Text syntax tree node.
     */
    public Text() {
        _textElement = true;
    }

    
Create text syntax tree node.
Params:
text – is the text to put in the node./**
     * Create text syntax tree node.
     * @param text is the text to put in the node.
     */
    public Text(String text) {
        _text = text;
    }

    
Returns the text wrapped inside this node
Returns:
The text wrapped inside this node/**
     * Returns the text wrapped inside this node
     * @return The text wrapped inside this node
     */
    protected String getText() {
        return _text;
    }

    
Set the text for this node. Appends the given text to any already
existing text (using string concatenation, so use only when needed).
Params:
text – is the text to wrap inside this node./**
     * Set the text for this node. Appends the given text to any already
     * existing text (using string concatenation, so use only when needed).
     * @param text is the text to wrap inside this node.
     */
    protected void setText(String text) {
        if (_text == null)
            _text = text;
        else
            _text = _text + text;
    }

    public void display(int indent) {
        indent(indent);
        Util.println("Text");
        indent(indent + IndentIncrement);
        Util.println(_text);
    }

    public void parseContents(Parser parser) {
        final String str = getAttribute("disable-output-escaping");
        if ((str != null) && (str.equals("yes"))) _escaping = false;

        parseChildren(parser);

        if (_text == null) {
            if (_textElement) {
                _text = EMPTYSTRING;
            }
            else {
                _ignore = true;
            }
        }
        else if (_textElement) {
            if (_text.length() == 0) _ignore = true;
        }
        else if (getParent() instanceof LiteralElement) {
            LiteralElement element = (LiteralElement)getParent();
            String space = element.getAttribute("xml:space");
            if ((space == null) || (!space.equals("preserve")))
        {
            int i;
            final int textLength = _text.length();
            for (i = 0; i < textLength; i++) {
                char c = _text.charAt(i);
                if (!isWhitespace(c))
                    break;
            }
            if (i == textLength)
                _ignore = true;
        }
        }
        else {
        int i;
        final int textLength = _text.length();
        for (i = 0; i < textLength; i++)
        {
            char c = _text.charAt(i);
            if (!isWhitespace(c))
                break;
        }
        if (i == textLength)
            _ignore = true;
        }
    }

    public void ignore() {
        _ignore = true;
    }

    public boolean isIgnore() {
        return _ignore;
    }

    public boolean isTextElement() {
        return _textElement;
    }

    protected boolean contextDependent() {
        return false;
    }

    private static boolean isWhitespace(char c)
    {
        return (c == 0x20 || c == 0x09 || c == 0x0A || c == 0x0D);
    }

    public void translate(ClassGenerator classGen, MethodGenerator methodGen) {
        final ConstantPoolGen cpg = classGen.getConstantPool();
        final InstructionList il = methodGen.getInstructionList();

        if (!_ignore) {
            // Turn off character escaping if so is wanted.
            final int esc = cpg.addInterfaceMethodref(OUTPUT_HANDLER,
                                                      "setEscaping", "(Z)Z");
            if (!_escaping) {
                il.append(methodGen.loadHandler());
                il.append(new PUSH(cpg, false));
                il.append(new INVOKEINTERFACE(esc, 2));
            }

            il.append(methodGen.loadHandler());

            // Call characters(String) or characters(char[],int,int), as
            // appropriate.
            if (!canLoadAsArrayOffsetLength()) {
                final int characters = cpg.addInterfaceMethodref(OUTPUT_HANDLER,
                                                           "characters",
                                                           "("+STRING_SIG+")V");
                il.append(new PUSH(cpg, _text));
                il.append(new INVOKEINTERFACE(characters, 2));
            } else {
                final int characters = cpg.addInterfaceMethodref(OUTPUT_HANDLER,
                                                                 "characters",
                                                                 "([CII)V");
                loadAsArrayOffsetLength(classGen, methodGen);
                il.append(new INVOKEINTERFACE(characters, 4));
            }

            // Restore character escaping setting to whatever it was.
            // Note: setEscaping(bool) returns the original (old) value
            if (!_escaping) {
                il.append(methodGen.loadHandler());
                il.append(SWAP);
                il.append(new INVOKEINTERFACE(esc, 2));
                il.append(POP);
            }
        }
        translateContents(classGen, methodGen);
    }

    
Check whether this Text node can be stored in a char[] in the translet.
Calling this is precondition to calling loadAsArrayOffsetLength.
See Also:
loadAsArrayOffsetLength(ClassGenerator, MethodGenerator)
Returns:
true if this Text node can be/**
     * Check whether this Text node can be stored in a char[] in the translet.
     * Calling this is precondition to calling loadAsArrayOffsetLength.
     * @see #loadAsArrayOffsetLength(ClassGenerator,MethodGenerator)
     * @return true if this Text node can be
     */
    public boolean canLoadAsArrayOffsetLength() {
        // Magic number!  21845*3 == 65535.  BCEL uses a DataOutputStream to
        // serialize class files.  The Java run-time places a limit on the size
        // of String data written using a DataOutputStream - it cannot require
        // more than 64KB when represented as UTF-8.  The number of bytes
        // required to represent a Java string as UTF-8 cannot be greater
        // than three times the number of char's in the string, hence the
        // check for 21845.

        return (_text.length() <= 21845);
    }

    
Generates code that loads the array that will contain the character
data represented by this Text node, followed by the offset of the
data from the start of the array, and then the length of the data.
The pre-condition to calling this method is that
canLoadAsArrayOffsetLength() returns true.
See Also:
canLoadArrayOffsetLength()/**
     * Generates code that loads the array that will contain the character
     * data represented by this Text node, followed by the offset of the
     * data from the start of the array, and then the length of the data.
     *
     * The pre-condition to calling this method is that
     * canLoadAsArrayOffsetLength() returns true.
     * @see #canLoadArrayOffsetLength()
     */
    public void loadAsArrayOffsetLength(ClassGenerator classGen,
                                        MethodGenerator methodGen) {
        final ConstantPoolGen cpg = classGen.getConstantPool();
        final InstructionList il = methodGen.getInstructionList();
        final XSLTC xsltc = classGen.getParser().getXSLTC();

        // The XSLTC object keeps track of character data
        // that is to be stored in char arrays.
        final int offset = xsltc.addCharacterData(_text);
        final int length = _text.length();
        String charDataFieldName =
            STATIC_CHAR_DATA_FIELD + (xsltc.getCharacterDataCount()-1);

        il.append(new GETSTATIC(cpg.addFieldref(xsltc.getClassName(),
                                       charDataFieldName,
                                       STATIC_CHAR_DATA_FIELD_SIG)));
        il.append(new PUSH(cpg, offset));
        il.append(new PUSH(cpg, _text.length()));
    }
}