Java Tutorial/Network/HTML Parser — различия между версиями

Текущая версия на 05:03, 1 июня 2010

Содержание

1 Escape HTML special characters from a String
2 extends HTMLEditorKit.ParserCallback
3 Extract links from an HTML page
4 Find and display hyperlinks contained within a web page
5 Get all hyper links from a web page
6 Getting the Links in an HTML Document
7 Getting the Text in an HTML Document
8 HTML Parser
9 HTML parser based on HTMLEditorKit.ParserCallback
10 Using javax.swing.text.html.HTMLEditorKit to parse html document

Escape HTML special characters from a String

public class Main {
  public static void main(String[] argv){
    System.out.println(escapeHTML("><"));
  }
  
  public static final String escapeHTML(String s) {
    StringBuffer sb = new StringBuffer();
    int n = s.length();
    for (int i = 0; i < n; i++) {
      char c = s.charAt(i);
      switch (c) {
      case "<":
        sb.append("&lt;");
        break;
      case ">":
        sb.append("&gt;");
        break;
      case "&":
        sb.append("&amp;");
        break;
      case """:
        sb.append("&quot;");
        break;
      case "&agrave;":
        sb.append("&agrave;");
        break;
      case "�":
        sb.append("&Agrave;");
        break;
      case "&acirc;":
        sb.append("&acirc;");
        break;
      case "�":
        sb.append("&Acirc;");
        break;
      case "&auml;":
        sb.append("&auml;");
        break;
      case "&Auml;":
        sb.append("&Auml;");
        break;
      case "&aring;":
        sb.append("&aring;");
        break;
      case "&Aring;":
        sb.append("&Aring;");
        break;
      case "&aelig;":
        sb.append("&aelig;");
        break;
      case "&AElig;":
        sb.append("&AElig;");
        break;
      case "&ccedil;":
        sb.append("&ccedil;");
        break;
      case "&Ccedil;":
        sb.append("&Ccedil;");
        break;
      case "&eacute;":
        sb.append("&eacute;");
        break;
      case "�":
        sb.append("&Eacute;");
        break;
      case "&egrave;":
        sb.append("&egrave;");
        break;
      case "�":
        sb.append("&Egrave;");
        break;
      case "&ecirc;":
        sb.append("&ecirc;");
        break;
      case "�":
        sb.append("&Ecirc;");
        break;
      case "&euml;":
        sb.append("&euml;");
        break;
      case "&Euml;":
        sb.append("&Euml;");
        break;
      case "�":
        sb.append("&iuml;");
        break;
      case "�":
        sb.append("&Iuml;");
        break;
      case "&ocirc;":
        sb.append("&ocirc;");
        break;
      case "�":
        sb.append("&Ocirc;");
        break;
      case "&ouml;":
        sb.append("&ouml;");
        break;
      case "&Ouml;":
        sb.append("&Ouml;");
        break;
      case "&oslash;":
        sb.append("&oslash;");
        break;
      case "&Oslash;":
        sb.append("&Oslash;");
        break;
      case "&szlig;":
        sb.append("&szlig;");
        break;
      case "&ugrave;":
        sb.append("&ugrave;");
        break;
      case "�":
        sb.append("&Ugrave;");
        break;
      case "&ucirc;":
        sb.append("&ucirc;");
        break;
      case "�":
        sb.append("&Ucirc;");
        break;
      case "&uuml;":
        sb.append("&uuml;");
        break;
      case "&Uuml;":
        sb.append("&Uuml;");
        break;
      case "�":
        sb.append("&reg;");
        break;
      case "�":
        sb.append("&copy;");
        break;
      case "�":
        sb.append("&euro;");
        break;
      case " ":
        sb.append("&nbsp;");
        break;
      default:
        sb.append(c);
        break;
      }
    }
    return sb.toString();
  }
}
//&gt;&lt;

extends HTMLEditorKit.ParserCallback

import java.io.InputStream;
import java.io.InputStreamReader;
import java.io.Reader;
import java.net.URL;
import javax.swing.text.html.HTMLEditorKit;
import javax.swing.text.html.parser.ParserDelegator;
public class Main {
  public static void main(String args[]) throws Exception {
    URL url = new URL(args[0]);
    Reader reader = new InputStreamReader((InputStream) url.getContent());
    new ParserDelegator().parse(reader, new TextOnly(), false);
  }
}
class TextOnly extends HTMLEditorKit.ParserCallback {
  public void handleText(char[] data, int pos) {
    System.out.println(data);
  }
}

Extract links from an HTML page

import java.io.FileReader;
import java.util.ArrayList;
import javax.swing.text.MutableAttributeSet;
import javax.swing.text.html.HTML.Attribute;
import javax.swing.text.html.HTML.Tag;
import javax.swing.text.html.HTMLEditorKit.ParserCallback;
import javax.swing.text.html.parser.ParserDelegator;
public class Main {
  public final static void main(String[] args) throws Exception {
    final ArrayList<String> list = new ArrayList<String>();
    ParserDelegator parserDelegator = new ParserDelegator();
    ParserCallback parserCallback = new ParserCallback() {
      public void handleText(final char[] data, final int pos) {
      }
      public void handleStartTag(Tag tag, MutableAttributeSet attribute, int pos) {
        if (tag == Tag.A) {
          String address = (String) attribute.getAttribute(Attribute.HREF);
          list.add(address);
        }
      }
      public void handleEndTag(Tag t, final int pos) {
      }
      public void handleSimpleTag(Tag t, MutableAttributeSet a, final int pos) {
      }
      public void handleComment(final char[] data, final int pos) {
      }
      public void handleError(final java.lang.String errMsg, final int pos) {
      }
    };
    parserDelegator.parse(new FileReader("a.html"), parserCallback, false);
    System.out.println(list);
  }
}

Find and display hyperlinks contained within a web page

import java.io.BufferedReader;
import java.io.FileReader;
import java.util.regex.Matcher;
import java.util.regex.Pattern;
public class Main {
  public static void main(String[] arguments)throws Exception {
    StringBuffer output = new StringBuffer();
    FileReader file = new FileReader("a.htm");
    BufferedReader buff = new BufferedReader(file);
    boolean eof = false;
    while (!eof) {
      String line = buff.readLine();
      if (line == null)
        eof = true;
      else
        output.append(line + "\n");
    }
    buff.close();
    String page = output.toString();
    Pattern pattern = Pattern.rupile("<a.+href=\"(.+?)\"");
    Matcher matcher = pattern.matcher(page);
    while (matcher.find()) {
      System.out.println(matcher.group(1));
    }
  }
}

Get all hyper links from a web page

import java.io.InputStream;
import java.io.InputStreamReader;
import java.io.Reader;
import java.net.URL;
import javax.swing.text.MutableAttributeSet;
import javax.swing.text.html.HTML;
import javax.swing.text.html.HTMLEditorKit;
import javax.swing.text.html.parser.ParserDelegator;
public class Main {
  public static void main(String args[]) throws Exception {
    URL url = new URL(args[0]);
    Reader reader = new InputStreamReader((InputStream) url.getContent());
    System.out.println("<HTML><HEAD><TITLE>Links for " + args[0] + "</TITLE>");
    System.out.println("<BASE HREF=\"" + args[0] + "\"></HEAD>");
    System.out.println("<BODY>");
    new ParserDelegator().parse(reader, new LinkPage(), false);
    System.out.println("</BODY></HTML>");
  }
}
class LinkPage extends HTMLEditorKit.ParserCallback {
  public void handleStartTag(HTML.Tag t, MutableAttributeSet a, int pos) {
    if (t == HTML.Tag.A) {
      System.out.println("<BR>");
    }
  }
}

Getting the Links in an HTML Document

import java.io.InputStreamReader;
import java.io.Reader;
import java.net.URI;
import java.net.URL;
import java.net.URLConnection;
import javax.swing.text.EditorKit;
import javax.swing.text.SimpleAttributeSet;
import javax.swing.text.html.HTML;
import javax.swing.text.html.HTMLDocument;
import javax.swing.text.html.HTMLEditorKit;
public class Main {
  public static void main(String[] argv) throws Exception {
    URL url = new URI("http://www.google.ru").toURL();
    URLConnection conn = url.openConnection();
    Reader rd = new InputStreamReader(conn.getInputStream());
    EditorKit kit = new HTMLEditorKit();
    HTMLDocument doc = (HTMLDocument) kit.createDefaultDocument();
    kit.read(rd, doc, 0);
    HTMLDocument.Iterator it = doc.getIterator(HTML.Tag.A);
    while (it.isValid()) {
      SimpleAttributeSet s = (SimpleAttributeSet) it.getAttributes();
      String link = (String) s.getAttribute(HTML.Attribute.HREF);
      if (link != null) {
        System.out.println(link);
      }
      it.next();
    }
  }
}

Getting the Text in an HTML Document

import java.io.InputStreamReader;
import java.io.Reader;
import java.net.URI;
import java.net.URL;
import java.net.URLConnection;
import javax.swing.text.EditorKit;
import javax.swing.text.html.HTMLDocument;
import javax.swing.text.html.HTMLEditorKit;
public class Main {
  public static void main(String[] argv) throws Exception {
    HTMLDocument doc = new HTMLDocument() {
      public HTMLEditorKit.ParserCallback getReader(int pos) {
        return new HTMLEditorKit.ParserCallback() {
          public void handleText(char[] data, int pos) {
            System.out.println(data);
          }
        };
      }
    };
    URL url = new URI("http://www.google.ru").toURL();
    URLConnection conn = url.openConnection();
    Reader rd = new InputStreamReader(conn.getInputStream());
    EditorKit kit = new HTMLEditorKit();
    kit.read(rd, doc, 0);
  }
}

HTML Parser

/*******************************************************************************
 * Copyright (c) 2004 Actuate Corporation.
 * All rights reserved. This program and the accompanying materials
 * are made available under the terms of the Eclipse Public License v1.0
 * which accompanies this distribution, and is available at
 * http://www.eclipse.org/legal/epl-v10.html
 *
 * Contributors:
 *  Actuate Corporation  - initial API and implementation
 *******************************************************************************/

import java.io.FileNotFoundException;
import java.io.FileReader;
import java.io.IOException;
import java.io.LineNumberReader;
import java.util.ArrayList;
public class HTMLParser
{
  FileReader reader;
  LineNumberReader in;
  String token;
  ArrayList attribs = new ArrayList( );
  int pushC = -1;
  private boolean ignoreWhitespace = true;
  
  public static final int EOF = -1;
  public static final int TEXT = 1;
  public static final int DOCTYPE = 2;
  public static final int ELEMENT = 3;
  public static final int COMMENT = 4;
  public static final int SPECIAL_ELEMENT = 5;
  
  public static final int START_ELEMENT = 0;
  public static final int END_ELEMENT = 1;
  public static final int SINGLE_ELEMENT = 2;
  
  public HTMLParser( )
  {
  }
  
  public void open( String fileName ) throws FileNotFoundException
  {
    reader = new FileReader( fileName );
    in = new LineNumberReader( reader );
  }
  
  /**
   * 
   */
  public void close( )
  {
    try
    {
      in.close( );
      reader.close( );
    }
    catch ( IOException e1 )
    {
      // Ignore
    }
  }
  public String getTokenText( )
  {
    return token;
  }
  
  public int getElementType( )
  {
    if ( token.startsWith( "/" ) ) //$NON-NLS-1$
      return END_ELEMENT;
    if ( token.endsWith( "/" ) ) //$NON-NLS-1$
      return SINGLE_ELEMENT;
    return START_ELEMENT;
  }
  
  public String getElement( )
  {
    if ( token.startsWith( "/" ) ) //$NON-NLS-1$
      return token.substring( 1 );
    if ( token.endsWith( "/" ) ) //$NON-NLS-1$
      return token.substring( 0, token.length( ) - 1 );
    return token;
    
  }
  
  public ArrayList getAttribs( )
  {
    return attribs;
  }
  
  public String getAttrib( String name )
  {
    for ( int i = 0;  i < attribs.size( );  i++ )
    {
      AttribPair a = (AttribPair) attribs.get( i );
      if ( a.attrib.equalsIgnoreCase( name ) )
        return a.value;
    }
    return null;
  }
  
  private int getC( )
  {
    if ( pushC != -1 )
    {
      int c = pushC;
      pushC = -1;
      return c;
    }
    try
    {
      return in.read( );
    }
    catch ( IOException e )
    {
      return EOF;
    }
  }
  
  private void pushC( int c )
  {
    pushC = c;
  }
  
  public int getToken( )
  {
    for ( ; ; )
    {
      int c = getC( );
      switch ( c )
      {
        case -1:
          return EOF;
        case "<":
          return getElement( c );
        default:
        {
          parseText( c );
          if ( ! ignoreWhitespace  ||  token.trim( ).length( ) > 0 )
            return TEXT;
        }
      }
    }
  }
  private int parseText( int c )
  {
    StringBuffer text = new StringBuffer( );
    for ( ; ; )
    {
      if ( c == EOF )
        break;
      if ( c == "<" )
      {
        pushC( c );
        break;
      }
      
      // Convert MS-Word-style quotes.
      
      if ( c == 8220  ||  c == 8221 )
        text.append( "&quot;" );
      else
        text.append( (char) c );
      c = getC( );
    }
    token = text.toString( );
    return TEXT;
  }
  private int skipSpace( int c )
  {
    while ( c != EOF  &&  Character.isWhitespace( (char)c ) )
    {
      c = getC( );
    }
    return c;
  }
  
  private int getElement( int c )
  {
    c = getC( );
    
    // Broken element
    
    if ( c == EOF )
      return EOF;
    
    if ( c == "!" )
      return getSpecialElement( );
    
    attribs.clear( );
    c = skipSpace( c );
    if ( c == EOF )
      return EOF;
    
    StringBuffer tag = new StringBuffer( );
    if ( c == "/" )
    {
      tag.append( (char) c );
      c = skipSpace( getC( ) );
      while ( c != EOF  &&  c != ">"  && ! Character.isWhitespace( (char)c ) )
      {
        tag.append( (char) c );
        c = getC( );
      }
      token = tag.toString( );
      for ( ; ; )
      {
        if ( c == ">"  ||  c == -1 )
          break;
        c = getC( );
      }
      return ELEMENT;     
    }
    
    while ( c != EOF  &&  c != ">"  &&  c != "/"  && ! Character.isWhitespace( (char)c ) )
    {
      tag.append( (char) c );
      c = getC( );
    }
    if ( c == EOF )
    {
      token = tag.toString( );
      return ELEMENT;
    }
    
    for ( ; ; )
    {
      c = skipSpace( c );
      if ( c == EOF  ||  c == ">" || c == "/" )
        break;
      c = getAttrib( c );
    }
    if ( c == "/" )
    {
      tag.append( (char) c );
      for ( ; ; )
      {
        c = getC( );
        if ( c == -1  ||  c == ">" )
          break;
      }
    }
    token = tag.toString( );
    return ELEMENT;
  }
  
  private int getAttrib( int c )
  {
    AttribPair a = new AttribPair( );
    StringBuffer s = new StringBuffer( );
    while ( c != EOF  &&  c != "="  &&  ! Character.isWhitespace( (char)c ) )
    {
      s.append( (char) c );
      c = getC( );
    }
    a.attrib = s.toString( );
    c = skipSpace( c );
    if ( c != "=" )
    {
      attribs.add( a );
      return c;
    }
    s = new StringBuffer( );
    c = skipSpace( getC( ) );
    if ( c == "\"" || c == """ )
    {
      int quote = c;
      for ( ; ; )
      {
        c = getC( );
        if ( c == -1 )
          break;
        if ( c == quote )
        {
          c = getC( );
          break;
        }
        if ( c == "\\" )
        {
          c = getC( );
          if ( c == EOF )
            break;
          s.append( "\\" );
          s.append( (char) c );
        }
        else
        {
          s.append( (char) c );
        }
      }
    }
    else
    {
      for ( ; ; )
      {
        c = getC( );
        if ( c == -1 )
          break;
        if ( c == ">"  ||  c == "/"  ||  Character.isWhitespace( (char)c ) )
        {
          c = getC( );
          break;
        }
        s.append( (char) c );
      }
    }
    a.value = s.toString( );
    attribs.add( a );
    return c;
  }
  
  class AttribPair
  {
    String attrib;
    String value;
  }
  
  private int getSpecialElement(  )
  {
    StringBuffer text = new StringBuffer( );
    text.append( "<!" ); //$NON-NLS-1$
    for ( ; ; )
    {
      int c = getC( );
      if ( c == EOF || c == ">" )
        break;
      text.append( (char) c );
    }
    text.append( ">" );
    token = text.toString( );
    if ( token.startsWith( "<!--" ) ) //$NON-NLS-1$
      return COMMENT;
    return SPECIAL_ELEMENT;
  }
  static String formatTags[ ] =
  {
      "i", "b",  //$NON-NLS-1$//$NON-NLS-2$
      "strong", "em",  //$NON-NLS-1$//$NON-NLS-2$
      "code", "span", //$NON-NLS-1$ //$NON-NLS-2$
      "a" //$NON-NLS-1$
  };
  
  public boolean isFormatTag( )
  {
    return isFormatTag( getElement( ) );
  }
  
  public boolean isFormatTag( String tag )
  {
    for ( int i = 0;  i < formatTags.length;  i++ )
    {
      if ( formatTags[ i ].equalsIgnoreCase( tag ) )
        return true;
    }
    return false;
  }
  public Object getFullElement( )
  {
    StringBuffer text = new StringBuffer( );
    text.append( "<" );
    int elementType = getElementType( );
    if ( elementType == END_ELEMENT )
      text.append( "/" );
    text.append( getElement( ) );
    
    for ( int i = 0;  i < attribs.size( );  i++ )
    {
      text.append( " " );
      AttribPair a = (AttribPair) attribs.get( i );
      text.append( a.attrib );
      text.append( "=\"" ); //$NON-NLS-1$
      if ( a.value != null )
        text.append( a.value );
      text.append( "\"" ); //$NON-NLS-1$
    }
    if ( elementType == SINGLE_ELEMENT )
      text.append( "/" );
    text.append( ">" );
    return text.toString( );
  }
  public int getLineNo( )
  {
    return in.getLineNumber( );
  }
  public void ignoreWhitespace( boolean b )
  {
    ignoreWhitespace = b;
  }
}

HTML parser based on HTMLEditorKit.ParserCallback

import java.io.InputStream;
import java.io.InputStreamReader;
import java.io.Reader;
import java.net.URL;
import javax.swing.text.MutableAttributeSet;
import javax.swing.text.html.HTML;
import javax.swing.text.html.HTMLEditorKit;
import javax.swing.text.html.parser.ParserDelegator;
public class Main {
  public static void main(String args[]) throws Exception {
    URL url = new URL(args[0]);
    Reader reader = new InputStreamReader((InputStream) url.getContent());
    new ParserDelegator().parse(reader, new HTMLParse(), false);
  }
}
class HTMLParse extends HTMLEditorKit.ParserCallback {
  public void handleText(char[] data, int pos) {
    System.out.println(data);
  }
  public void handleStartTag(HTML.Tag t, MutableAttributeSet a, int pos) {
    System.out.println("+" + t.toString());
  }
  public void handleSimpleTag(HTML.Tag t, MutableAttributeSet a, int pos) {
    System.out.println("*" + t.toString());
  }
  public void handleEndTag(HTML.Tag t, int pos) {
    System.out.println("-" + t.toString());
  }
}

Using javax.swing.text.html.HTMLEditorKit to parse html document

import java.io.FileReader;
import java.io.IOException;
import java.io.Reader;
import java.util.ArrayList;
import java.util.List;
import javax.swing.text.MutableAttributeSet;
import javax.swing.text.html.HTML.Tag;
import javax.swing.text.html.HTMLEditorKit.ParserCallback;
import javax.swing.text.html.parser.ParserDelegator;
public class Main {
  public static void main(String[] args) throws Exception {
    final List<String> list = new ArrayList<String>();
    ParserDelegator parserDelegator = new ParserDelegator();
    ParserCallback parserCallback = new ParserCallback() {
      public void handleText(final char[] data, final int pos) {
        list.add(new String(data));
      }
      public void handleStartTag(Tag tag, MutableAttributeSet attribute, int pos) {
      }
      public void handleEndTag(Tag t, final int pos) {
      }
      public void handleSimpleTag(Tag t, MutableAttributeSet a, final int pos) {
      }
      public void handleComment(final char[] data, final int pos) {
      }
      public void handleError(final java.lang.String errMsg, final int pos) {
      }
    };
    parserDelegator.parse(new FileReader("a.html"), parserCallback, true);
    System.out.println(list);
  }
}

Java Tutorial/Network/HTML Parser — различия между версиями

Текущая версия на 05:03, 1 июня 2010

Содержание

Escape HTML special characters from a String

extends HTMLEditorKit.ParserCallback

Extract links from an HTML page

Find and display hyperlinks contained within a web page

Get all hyper links from a web page

Getting the Links in an HTML Document

Getting the Text in an HTML Document

HTML Parser

HTML parser based on HTMLEditorKit.ParserCallback

Using javax.swing.text.html.HTMLEditorKit to parse html document

Навигация

Персональные инструменты

Пространства имён

Варианты

Просмотры

Ещё

Поиск

Разделы

Навигация

Инструменты

Версия 17:44, 31 мая 2010 (просмотреть исходный код) (обсуждение)	Текущая версия на 05:03, 1 июня 2010 (просмотреть исходный код) Admin (обсуждение \| вклад) м (1 версия)
(нет различий)