/* * HtmlFormatter.java -- HTML document pretty-printer * Copyright (C) 1999 Quiotix Corporation.   * * This program is free software; you can redistribute it and/or modify * it under the terms of the GNU General Public License, version 2, as  * published by the Free Software Foundation.   * * This program 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 (http://www.gnu.org/copyleft/gpl.txt) * for more details. */package com.quiotix.html.parser;import java.io.*;import java.util.*;/**  * HtmlFormatter is a Visitor which traverses an HtmlDocument, dumping the * contents of the document to a specified output stream.  It assumes that * the documents has been preprocessed by HtmlCollector (which matches up * beginning and end tags) and by HtmlScrubber (which formats tags in a * consistent way).  In particular, HtmlScrubber should be invoked with the * TRIM_SPACES option to remove trailing spaces, which can confuse the  * formatting algorithm.  *  * <P>The right margin and indent increment can be specified as properties.   *  * @author Brian Goetz, Quiotix * @see com.quiotix.html.HtmlVisitor * @see com.quiotix.html.HtmlCollector * @see com.quiotix.html.HtmlScrubber */public class HtmlFormatter extends HtmlVisitor {  protected MarginWriter out;  protected int rightMargin=80;   protected int indentSize=2;  protected static Hashtable tagsIndentBlock = new Hashtable();  protected static Hashtable tagsNewlineBefore = new Hashtable();  protected static Hashtable tagsPreformatted = new Hashtable();  protected static Hashtable tagsTryMatch = new Hashtable();  protected static final String[] tagsIndentStrings    = { "TABLE", "TR", "TD", "TH", "FORM", "HTML", "HEAD", "BODY", "SELECT" };  protected static final String[] tagsNewlineBeforeStrings    = { "P", "H1", "H2", "H3", "H4", "H5", "H6", "BR" };  protected static final String[] tagsPreformattedStrings     = { "PRE", "SCRIPT", "STYLE" };  protected static final String[] tagsTryMatchStrings     = { "A", "TD", "TH", "TR", "I", "B", "EM", "FONT", "TT", "UL" };  static {    Integer dummy = new Integer(0);    for (int i=0; i < tagsIndentStrings.length; i++)       tagsIndentBlock.put(tagsIndentStrings[i], dummy);    for (int i=0; i < tagsNewlineBeforeStrings.length; i++)       tagsNewlineBefore.put(tagsNewlineBeforeStrings[i], dummy);    for (int i=0; i < tagsPreformattedStrings.length; i++)       tagsPreformatted.put(tagsPreformattedStrings[i], dummy);    for (int i=0; i < tagsTryMatchStrings.length; i++)       tagsTryMatch.put(tagsTryMatchStrings[i], dummy);  };  protected TagBlockRenderer blockRenderer = new TagBlockRenderer();  protected HtmlDocument.HtmlElement previousElement;  protected boolean inPreBlock;  public HtmlFormatter(OutputStream os) throws Exception {    out = new MarginWriter(new PrintWriter(new BufferedOutputStream(os)));    out.setRightMargin(rightMargin);  };  public void setRightMargin(int margin) {    rightMargin = margin;    out.setRightMargin(rightMargin);  };  public void setIndent(int indent) {    indentSize = indent;  };  public void visit(HtmlDocument.TagBlock block) {    boolean indent;    boolean preformat;    boolean alreadyDone = false;    int wasMargin=0;    if (tagsTryMatch.containsKey(block.startTag.tagName.toUpperCase())) {      blockRenderer.start();      blockRenderer.setTargetWidth(out.getRightMargin() - out.getLeftMargin());      blockRenderer.visit(block);      blockRenderer.finish();      if (!blockRenderer.hasBlownTarget()) {        out.printAutoWrap(blockRenderer.getString());        previousElement = block.endTag;        return;      };    };    // Only will get here if we've failed the try-block test    indent = tagsIndentBlock.containsKey(block.startTag.tagName.toUpperCase());    preformat = tagsPreformatted.containsKey(block.startTag.tagName.toUpperCase());    if (preformat) {      inPreBlock = true;      visit(block.startTag);      wasMargin = out.getLeftMargin();      out.setLeftMargin(0);      visit(block.body);      out.setLeftMargin(wasMargin);      visit(block.endTag);    } else if (indent) {      out.printlnSoft();      visit(block.startTag);      out.printlnSoft();      out.setLeftMargin(out.getLeftMargin() + indentSize);      visit(block.body);      out.setLeftMargin(out.getLeftMargin() - indentSize);      out.printlnSoft();      visit(block.endTag);      out.printlnSoft();      inPreBlock = false;    }    else {      visit(block.startTag);      visit(block.body);      visit(block.endTag);    };  }  public void visit(HtmlDocument.Tag t) {    String s = t.toString();    int hanging;     if (tagsNewlineBefore.containsKey(t.tagName.toUpperCase())        || out.getCurPosition() + s.length() > out.getRightMargin())      out.printlnSoft();    out.print("<" + t.tagName);    hanging = t.tagName.length() + 1;    for (Enumeration ae=t.attributeList.attributes.elements();         ae.hasMoreElements(); ) {      HtmlDocument.Attribute a = (HtmlDocument.Attribute) ae.nextElement();       out.printAutoWrap(" "+a.toString(), hanging);    };    if (t.emptyTag) out.print("/");    out.print(">");    previousElement = t;  }  public void visit(HtmlDocument.EndTag t) {    out.printAutoWrap(t.toString());    if (tagsNewlineBefore.containsKey(t.tagName.toUpperCase())) {      out.printlnSoft();      out.println();    };    previousElement = t;  }  public void visit(HtmlDocument.Comment c) {    out.print(c.toString());    previousElement = c;  }  public void visit(HtmlDocument.Text t) {    if (inPreBlock)       out.print(t.text);    else {      int start=0;      while (start < t.text.length()) {         int index = t.text.indexOf(' ', start) + 1;        if (index == 0)           index = t.text.length();        out.printAutoWrap(t.text.substring(start, index));        start = index;      };    };    previousElement = t;  }  public void visit(HtmlDocument.Newline n) {    if (inPreBlock)      out.println();    else if (previousElement instanceof HtmlDocument.Tag             || previousElement instanceof HtmlDocument.EndTag             || previousElement instanceof HtmlDocument.Comment             || previousElement instanceof HtmlDocument.Newline)      out.printlnSoft();    else if (previousElement instanceof HtmlDocument.Text)       out.print(" ");    previousElement = n;  }  public void start() {    previousElement = null;    inPreBlock = false;  };  public void finish() {    out.flush();  };  public static void main (String[] args) throws Exception {    InputStream r = new FileInputStream(args[0]);    HtmlDocument document;        try {       document = new HtmlParser(r).HtmlDocument();      document.accept(new HtmlCollector());      document.accept(new HtmlScrubber(HtmlScrubber.DEFAULT_OPTIONS                                        | HtmlScrubber.TRIM_SPACES));      document.accept(new HtmlFormatter(System.out));    }    catch (Exception e) {      e.printStackTrace();    }    finally {      r.close();    };  };}    /**  * Utility class, used by HtmlFormatter, which adds some word-wrapping  * and hanging indent functionality to a PrintWriter.  */class MarginWriter {  protected int tabStop;  protected int curPosition;  protected int leftMargin;  protected int rightMargin;  protected java.io.PrintWriter out;  protected char[] spaces = new char[256];  {    for (int i=0; i<spaces.length; i++)       spaces[i] =  ' ';  };    public MarginWriter(java.io.PrintWriter out) {     this.out = out;   }  public void flush() {    out.flush();  };  public void close() {    out.close();  };  public void print(String s) {    if (curPosition == 0 && leftMargin > 0) {      out.write(spaces, 0, leftMargin);      curPosition = leftMargin;    };    out.print(s);    curPosition += s.length();  }  public void printAutoWrap(String s) {    if (curPosition > leftMargin        && curPosition + s.length() > rightMargin)       println();    print(s);  };  public void printAutoWrap(String s, int hanging) {    if (curPosition > leftMargin        && curPosition + s.length() > rightMargin) {      println();      out.write(spaces, 0, hanging+leftMargin);      curPosition = leftMargin + hanging;    };    print(s);  };  public void println() {    curPosition = 0;    out.println();  };  public void printlnSoft() {    if (curPosition > 0)       println();  };  public void setLeftMargin(int leftMargin) {     this.leftMargin = leftMargin;  };  public int getLeftMargin() {     return leftMargin;   };  public void setRightMargin(int rightMargin) {     this.rightMargin = rightMargin;   };  public int getRightMargin() {    return rightMargin;  };  public int getCurPosition() {    return (curPosition == 0 ? leftMargin : curPosition);  };}/**  * Utility class, used by HtmlFormatter, which tentatively tries to format * the contents of an HtmlDocument.TagBlock to see if the entire block can * fit on the rest of the line.  If it cannot, it gives up and indicates  * failure through the hasBlownTarget method; if it can, the contents can * be retrieved through the getString method. */class TagBlockRenderer extends HtmlVisitor {  protected String s;  protected boolean multiLine;  protected boolean blownTarget;  protected int targetWidth=80;   public void start() {     s = "";     multiLine = false;     blownTarget = false;  }  public void finish() { };  public void setTargetWidth(int w) { targetWidth = w; }  public String getString()         { return s; }  public boolean isMultiLine()      { return multiLine; }  public boolean hasBlownTarget()   { return blownTarget; }  public void visit(HtmlDocument.Tag t)     {     if (s.length() < targetWidth)         s += t.toString();     else       blownTarget = true;  }  public void visit(HtmlDocument.EndTag t) {    if (s.length() < targetWidth)         s += t.toString();     else       blownTarget = true;  }  public void visit(HtmlDocument.Comment c) {     if (s.length() < targetWidth)         s += c.toString();     else       blownTarget = true;  }  public void visit(HtmlDocument.Text t)    {     if (s.length() < targetWidth)         s += t.toString();     else       blownTarget = true;  }  public void visit(HtmlDocument.Newline n) {     multiLine = true;     s += " ";   }}