// HTMLParser Library - A java-based parser for HTML
// http://htmlparser.org
// Copyright (C) 2006 Derrick Oswald
//
// Revision Control Information
//
// $URL: https://svn.sourceforge.net/svnroot/htmlparser/trunk/lexer/src/main/java/org/htmlparser/lexer/Page.java $
// $Author: derrickoswald $
// $Date: 2006-09-16 10:44:17 -0400 (Sat, 16 Sep 2006) $
// $Revision: 4 $
//
// This library is free software; you can redistribute it and/or
// modify it under the terms of the Common Public License; either
// version 1.0 of the License, or (at your option) any later version.
//
// This library 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
// Common Public License for more details.
//
// You should have received a copy of the Common Public License
// along with this library; if not, the license is available from
// the Open Source Initiative (OSI) website:
// http://opensource.org/licenses/cpl1.0.php
package org.htmlparser.lexer;
import java.io.InputStream;
import java.io.IOException;
import java.io.ObjectInputStream;
import java.io.ObjectOutputStream;
import java.io.Serializable;
import java.io.UnsupportedEncodingException;
import java.lang.reflect.InvocationTargetException;
import java.lang.reflect.Method;
import java.net.MalformedURLException;
import java.net.URL;
import java.net.URLConnection;
import java.net.UnknownHostException;
import java.util.zip.GZIPInputStream;
import java.util.zip.Inflater;
import java.util.zip.InflaterInputStream;
import org.htmlparser.http.ConnectionManager;
import org.htmlparser.util.ParserException;
/**
* Represents the contents of an HTML page.
* Contains the source of characters and an index of positions of line
* separators (actually the first character position on the next line).
*/
public class Page
implements
Serializable
{
/**
* The default charset.
* This should be <code>{@value}</code>,
* see RFC 2616 (http://www.ietf.org/rfc/rfc2616.txt?number=2616)
* section 3.7.1
* <p>Another alias is "8859_1".
*/
public static final String DEFAULT_CHARSET = "ISO-8859-1";
/**
* The default content type.
* In the absence of alternate information, assume html content ({@value}).
*/
public static final String DEFAULT_CONTENT_TYPE = "text/html";
/**
* Character value when the page is exhausted.
* Has a value of {@value}.
*/
public static final char EOF = (char)Source.EOF;
/**
* The URL this page is coming from.
* Cached value of <code>getConnection().toExternalForm()</code> or
* <code>setUrl()</code>.
*/
protected String mUrl;
/**
* The base URL for this page.
*/
protected String mBaseUrl;
/**
* The source of characters.
*/
protected Source mSource;
/**
* Character positions of the first character in each line.
*/
protected PageIndex mIndex;
/**
* The connection this page is coming from or <code>null</code>.
*/
protected transient URLConnection mConnection;
/**
* Connection control (proxy, cookies, authorization).
*/
protected static ConnectionManager mConnectionManager =
new ConnectionManager ();
/**
* Construct an empty page.
*/
public Page ()
{
this ("");
}
/**
* Construct a page reading from a URL connection.
* @param connection A fully conditioned connection. The connect()
* method will be called so it need not be connected yet.
* @exception ParserException An exception object wrapping a number of
* possible error conditions, some of which are outlined below.
* <li>IOException If an i/o exception occurs creating the
* source.</li>
* <li>UnsupportedEncodingException if the character set specified in the
* HTTP header is not supported.</li>
*/
public Page (URLConnection connection) throws ParserException
{
if (null == connection)
throw new IllegalArgumentException ("connection cannot be null");
setConnection (connection);
mBaseUrl = null;
}
/**
* Construct a page from a stream encoded with the given charset.
* @param stream The source of bytes.
* @param charset The encoding used.
* If null, defaults to the <code>DEFAULT_CHARSET</code>.
* @exception UnsupportedEncodingException If the given charset
* is not supported.
*/
public Page (InputStream stream, String charset)
throws
UnsupportedEncodingException
{
if (null == stream)
throw new IllegalArgumentException ("stream cannot be null");
if (null == charset)
charset = DEFAULT_CHARSET;
mSource = new InputStreamSource (stream, charset);
mIndex = new PageIndex (this);
mConnection = null;
mUrl = null;
mBaseUrl = null;
}
/**
* Construct a page from the given string.
* @param text The HTML text.
* @param charset <em>Optional</em>. The character set encoding that will
* be reported by {@link #getEncoding}. If charset is <code>null</code>
* the default character set is used.
*/
public Page (String text, String charset)
{
if (null == text)
throw new IllegalArgumentException ("text cannot be null");
if (null == charset)
charset = DEFAULT_CHARSET;
mSource = new StringSource (text, charset);
mIndex = new PageIndex (this);
mConnection = null;
mUrl = null;
mBaseUrl = null;
}
/**
* Construct a page from the given string.
* The page will report that it is using an encoding of
* {@link #DEFAULT_CHARSET}.
* @param text The HTML text.
*/
public Page (String text)
{
this (text, null);
}
/**
* Construct a page from a source.
* @param source The source of characters.
*/
public Page (Source source)
{
if (null == source)
throw new IllegalArgumentException ("source cannot be null");
mSource = source;
mIndex = new PageIndex (this);
mConnection = null;
mUrl = null;
mBaseUrl = null;
}
//
// static methods
//
/**
* Get the connection manager all Parsers use.
* @return The connection manager.
*/
public static ConnectionManager getConnectionManager ()
{
return (mConnectionManager);
}
/**
* Set the connection manager to use.
* @param manager The new connection manager.
*/
public static void setConnectionManager (ConnectionManager manager)
{
mConnectionManager = manager;
}
/**
* Get a CharacterSet name corresponding to a charset parameter.
* @param content A text line of the form:
* <pre>
* text/html; charset=Shift_JIS
* </pre>
* which is applicable both to the HTTP header field Content-Type and
* the meta tag http-equiv="Content-Type".
* Note this method also handles non-compliant quoted charset directives
* such as:
* <pre>
* text/html; charset="UTF-8"
* </pre>
* and
* <pre>
* text/html; charset='UTF-8'
* </pre>
* @return The character set name to use when reading the input stream.
* For JDKs that have the Charset class this is qualified by passing
* the name to findCharset() to render it into canonical form.
* If the charset parameter is not found in the given string, the default
* character set is returned.
* @see #findCharset
* @see #DEFAULT_CHARSET
*/
public String getCharset (String content)
{
final String CHARSET_STRING = "charset";
int index;
String ret;
if (null == mSource)
ret = DEFAULT_CHARSET;
else
// use existing (possibly supplied) character set:
// bug #1322686 when illegal charset specified
ret = mSource.getEncoding ();
if (null != content)
{
index = content.indexOf (CHARSET_STRING);
if (index != -1)
{
content = content.substring (index +
CHARSET_STRING.length ()).trim ();
if (content.startsWith ("="))
{
content = content.substring (1).trim ();
index = content.indexOf (";");
if (index != -1)
content = content.substring (0, index);
//remove any double quotes from around charset string
if (content.startsWith ("\"") && content.endsWith ("\"")
&& (1 < content.length ()))
content = content.substring (1, content.length () - 1);
//remove any single quote from around charset string
if (content.startsWith ("'") && content.endsWith ("'")
&& (1 < content.length ()))
content = content.substring (1, content.length () - 1);
ret = findCharset (content, ret);
// Charset names are not case-sensitive;
// that is, case is always ignored when comparing
// charset names.
// if (!ret.equalsIgnoreCase (content))
// {
// System.out.println (
// "detected charset \""
// + content
// + "\", using \""
// + ret
// + "\"");
// }
}
}
}
return (ret);
}
/**
* Lookup a character set name.
* <em>Vacuous for JVM's without <code>java.nio.charset</code>.</em>
* This uses reflection so the code will still run under prior JDK's but
* in that case the default is always returned.
* @param name The name to look up. One of the aliases for a character set.
* @param fallback The name to return if the lookup fails.
* @return The character set name.
*/
public static String findCharset (String name, String fallback)
{
String ret;
try
{
Class cls;
Method method;
Object object;
cls = Class.forName ("java.nio.charset.Charset");
method = cls.getMethod ("forName", new Class[] { String.class });
object = method.invoke (null, new Object[] { name });
method = cls.getMethod ("name", new Class[] { });
object = method.invoke (object, new Object[] { });
ret = (String)object;
}
catch (ClassNotFoundException cnfe)
{
// for reflection exceptions, assume the name is correct
ret = name;
}
catch (NoSuchMethodException nsme)
{
// for reflection exceptions, assume the name is correct
ret = name;
}
catch (IllegalAccessException ia)
{
// for reflection exceptions, assume the name is correct
ret = name;
}
catch (InvocationTargetException ita)
{
// java.nio.charset.IllegalCharsetNameException
// and java.nio.charset.UnsupportedCharsetException
// return the default
ret = fallback;
System.out.println (
"unable to determine cannonical charset name for "
+ name
+ " - using "
+ fallback);
}
return (ret);
}
//
// Serialization support
//
/**
* Serialize the page.
* There are two modes to serializing a page based on the connected state.
* If connected, the URL and the current offset is saved, while if
* disconnected, the underling source is saved.
* @param out The object stream to store this object in.
* @exception IOException If there is a serialization problem.
*/
private void writeObject (ObjectOutputStream out)
throws
IOException
{
String href;
Source source;
PageIndex index;
// two cases, reading from a URL and not
if (null != getConnection ())
{
out.writeBoolean (true);
out.writeInt (mSource.offset ()); // need to preread this much
href = getUrl ();
out.writeObject (href);
setUrl (getConnection ().getURL ().toExternalForm ());
source = getSource ();
mSource = null; // don't serialize the source if we can avoid it
index = mIndex;
mIndex = null; // will get recreated; valid for the new page anyway?
out.defaultWriteObject ();
mSource = source;
mIndex = index;
}
else
{
out.writeBoolean (false);
href = getUrl ();
out.writeObject (href);
setUrl (null); // don't try and read a bogus URL
out.defaultWriteObject ();
setUrl (href);
}
}
/**
* Deserialize the page.
* For details see <code>writeObject()</code>.
* @param in The object stream to decode.
* @exception IOException If there is a deserialization problem with
* the stream.
* @exception ClassNotFoundException If the deserialized class can't be
* located with the current classpath and class loader.
*/
private void readObject (ObjectInputStream in)
throws
IOException,
ClassNotFoundException
{
boolean fromurl;
int offset;
String href;
URL url;
Cursor cursor;
fromurl = in.readBoolean ();
if (fromurl)
{
offset = in.readInt ();
href = (String)in.readObject ();
in.defaultReadObject ();
// open the URL
if (null != getUrl ())
{
url = new URL (getUrl ());
try
{
setConnection (url.openConnection ());
}
catch (ParserException pe)
{
throw new IOException (pe.getMessage ());
}
}
cursor = new Cursor (this, 0);
for (int i = 0; i < offset; i++)
try
{
getCharacter (cursor);
}
catch (ParserException pe)
{
throw new IOException (pe.getMessage ());
}
setUrl (href);
}
else
{
href = (String)in.readObject ();
in.defaultReadObject ();
setUrl (href);
}
}
/**
* Reset the page by resetting the source of characters.
*/
public void reset ()
{
getSource ().reset ();
mIndex = new PageIndex (this); // todo: is this really necessary?
}
/**
* Close the page by destroying the source of characters.
* @exception IOException If destroying the source encounters an error.
*/
public void close () throws IOException
{
if (null != getSource ())
getSource ().destroy ();
}
/**
* Clean up this page, releasing resources.
* Calls <code>close()</code>.
* @exception Throwable if <code>close()</code> throws an
* <code>IOException</code>.
*/
protected void finalize ()
throws
Throwable
{
close ();
}
/**
* Get the connection, if any.
* @return The connection object for this page, or null if this page
* is built from a stream or a string.
*/
public URLConnection getConnection ()
{
return (mConnection);
}
/**
* Set the URLConnection to be used by this page.
* Starts reading from the given connection.
* This also resets the current url.
* @param connection The connection to use.
* It will be connected by this method.
* @exception ParserException If the <code>connect()</code> method fails,
* or an I/O error occurs opening the input stream or the character set
* designated in the HTTP header is unsupported.
*/
public void setConnection (URLConnection connection)
throws
ParserException
{
Stream stream;
String type;
String charset;
String contentEncoding;
mConnection = connection;
try
{
getConnection ().connect ();
}
catch (UnknownHostException uhe)
{
throw new ParserException ("Connect to "
+ mConnection.getURL ().toExternalForm () + " failed.", uhe);
}
catch (IOException ioe)
{
throw new ParserException ("Exception connecting to "
+ mConnection.getURL ().toExternalForm ()
+ " (" + ioe.getMessage () + ").", ioe);
}
type = getContentType ();
charset = getCharset (type);
try
{
contentEncoding = connection.getContentEncoding();
if ((null != contentEncoding)
&& (-1 != contentEncoding.indexOf ("gzip")))
{
stream = new Stream (new GZIPInputStream (
getConnection ().getInputStream ()));
}
else if ((null != contentEncoding)
&& (-1 != contentEncoding.indexOf ("deflate")))
{
stream = new Stream (new InflaterInputStream (
getConnection ().getInputStream (), new Inflater (true)));
}
else
{
stream = new Stream (getConnection ().getInputStream ());
}
try
{
mSource = new InputStreamSource (stream, charset);
}
catch (UnsupportedEncodingException uee)
{
// StringBuffer msg;
//
// msg = new StringBuffer (1024);
// msg.append (getConnection ().getURL ().toExternalForm ());
// msg.append (" has an encoding (");
// msg.append (charset);
// msg.append (") which is not supported, using ");
// msg.append (DEFAULT_CHARSET);
// System.out.println (msg.toString ());
charset = DEFAULT_CHARSET;
mSource = new InputStreamSource (stream, charset);
}
}
catch (IOException ioe)
{
throw new ParserException ("Exception getting input stream from "
+ mConnection.getURL ().toExternalForm ()
+ " (" + ioe.getMessage () + ").", ioe);
}
mUrl = connection.getURL ().toExternalForm ();
mIndex = new PageIndex (this);
}
/**
* Get the URL for this page.
* This is only available if the page has a connection
* (<code>getConnection()</code> returns non-null), or the document base has
* been set via a call to <code>setUrl()</code>.
* @return The url for the connection, or <code>null</code> if there is
* no conenction or the document base has not been set.
*/
public String getUrl ()
{
return (mUrl);
}
/**
* Set the URL for this page.
* This doesn't affect the contents of the page, just the interpretation
* of relative links from this point forward.
* @param url The new URL.
*/
public void setUrl (String url)
{
mUrl = url;
}
/**
* Gets the baseUrl.
* @return The base URL for this page, or <code>null</code> if not set.
*/
public String getBaseUrl ()
{
return (mBaseUrl);
}
/**
* Sets the baseUrl.
* @param url The base url for this page.
*/
public void setBaseUrl (String url)
{
mBaseUrl = url;
}
/**
* Get the source this page is reading from.
* @return The current source.
*/
public Source getSource ()
{
return (mSource);
}
/**
* Try and extract the content type from the HTTP header.
* @return The content type.
*/
public String getContentType ()
{
URLConnection connection;
String content;
String ret;
ret = DEFAULT_CONTENT_TYPE;
connection = getConnection ();
if (null != connection)
{
// can't use connection#getContentType
// see Bug #1467712 Page#getCharset never works
content = connection.getHeaderField ("Content-Type");
if (null != content)
ret = content;
}
return (ret);
}
/**
* Read the character at the given cursor position.
* The cursor position can be only behind or equal to the
* current source position.
* Returns end of lines (EOL) as \n, by converting \r and \r\n to \n,
* and updates the end-of-line index accordingly.
* Advances the cursor position by one (or two in the \r\n case).
* @param cursor The position to read at.
* @return The character at that position, and modifies the cursor to
* prepare for the next read. If the source is exhausted a zero is returned.
* @exception ParserException If an IOException on the underlying source
* occurs, or an attempt is made to read characters in the future (the
* cursor position is ahead of the underlying stream)
*/
public char getCharacter (Cursor cursor)
throws
ParserException
{
int i;
int offset;
char ret;
i = cursor.getPosition ();
offset = mSource.offset ();
if (offset == i)
try
{
i = mSource.read ();
if (Source.EOF == i)
ret = EOF;
else
{
ret = (char)i;
cursor.advance ();
}
}
catch (IOException ioe)
{
throw new ParserException (
"problem reading a character at position "
+ cursor.getPosition (), ioe);
}
else if (offset > i)
{
// historic read
try
{
ret = mSource.getCharacter (i);
}
catch (IOException ioe)
{
throw new ParserException (
"can't read a character at position "
+ i, ioe);
}
cursor.advance ();
}
else
// hmmm, we could skip ahead, but then what about the EOL index
throw new ParserException (
"attempt to read future characters from source "
+ i + " > " + mSource.offset ());
// handle \r
if ('\r' == ret)
{ // switch to single character EOL
ret = '\n';
// check for a \n in the next position
if (mSource.offset () == cursor.getPosition ())
try
{
i = mSource.read ();
if (Source.EOF == i)
{
// do nothing
}
else if ('\n' == (char)i)
cursor.advance ();
else
try
{
mSource.unread ();
}
catch (IOException ioe)
{
throw new ParserException (
"can't unread a character at position "
+ cursor.getPosition (), ioe);
}
}
catch (IOException ioe)
{
throw new ParserException (
"problem reading a character at position "
+ cursor.getPosition (), ioe);
}
else
try
{
if ('\n' == mSource.getCharacter (cursor.getPosition ()))
cursor.advance ();
}
catch (IOException ioe)
{
throw new ParserException (
"can't read a character at position "
+ cursor.getPosition (), ioe);
}
}
if ('\n' == ret)
// update the EOL index in any case
mIndex.add (cursor);
return (ret);
}
/**
* Return a character.
* Handles end of lines (EOL) specially, retreating the cursor twice for
* the '\r\n' case.
* The cursor position is moved back by one (or two in the \r\n case).
* @param cursor The position to 'unread' at.
* @exception ParserException If an IOException on the underlying source
* occurs.
*/
public void ungetCharacter (Cursor cursor)
throws
ParserException
{
int i;
char ch;
cursor.retreat ();
i = cursor.getPosition ();
try
{
ch = mSource.getCharacter (i);
if (('\n' == ch) && (0 != i))
{
ch = mSource.getCharacter (i - 1);
if ('\r' == ch)
cursor.retreat ();
}
}
catch (IOException ioe)
{
throw new ParserException (
"can't read a character at position "
+ cursor.getPosition (), ioe);
}
}
/**
* Get the current encoding being used.
* @return The encoding used to convert characters.
*/
public String getEncoding ()
{
return (getSource ().getEncoding ());
}
/**
* Begins reading from the source with the given character set.
* If the current encoding is the same as the requested encoding,
* this method is a no-op. Otherwise any subsequent characters read from
* this page will have been decoded using the given character set.<p>
* Some magic happens here to obtain this result if characters have already
* been consumed from this page.
* Since a Reader cannot be dynamically altered to use a different character
* set, the underlying stream is reset, a new Source is constructed
* and a comparison made of the characters read so far with the newly
* read characters up to the current position.
* If a difference is encountered, or some other problem occurs,
* an exception is thrown.
* @param character_set The character set to use to convert bytes into
* characters.
* @exception ParserException If a character mismatch occurs between
* characters already provided and those that would have been returned
* had the new character set been in effect from the beginning. An
* exception is also thrown if the underlying stream won't put up with
* these shenanigans.
*/
public void setEncoding (String character_set)
throws
ParserException
{
getSource ().setEncoding (character_set);
}
/**
* Build a URL from the link and base provided using non-strict rules.
* @param link The (relative) URI.
* @param base The base URL of the page, either from the <BASE> tag
* or, if none, the URL the page is being fetched from.
* @return An absolute URL.
* @exception MalformedURLException If creating the URL fails.
* @see #constructUrl(String, String, boolean)
*/
public URL constructUrl (String link, String base)
throws MalformedURLException
{
return (constructUrl (link, base, false));
}
/**
* Build a URL from the link and base provided.
* @param link The (relative) URI.
* @param base The base URL of the page, either from the <BASE> tag
* or, if none, the URL the page is being fetched from.
* @param strict If <code>true</code> a link starting with '?' is handled
* according to <a href="http://www.ietf.org/rfc/rfc2396.txt">RFC 2396</a>,
* otherwise the common interpretation of a query appended to the base
* is used instead.
* @return An absolute URL.
* @exception MalformedURLException If creating the URL fails.
*/
public URL constructUrl (String link, String base, boolean strict)
throws MalformedURLException
{
String path;
boolean modified;
boolean absolute;
int index;
URL url; // constructed URL combining relative link and base
// Bug #1461473 Relative links starting with ?
if (!strict && ('?' == link.charAt (0)))
{ // remove query part of base if any
if (-1 != (index = base.lastIndexOf ('?')))
base = base.substring (0, index);
url = new URL (base + link);
}
else
url = new URL (new URL (base), link);
path = url.getFile ();
modified = false;
absolute = link.startsWith ("/");
if (!absolute)
{ // we prefer to fix incorrect relative links
// this doesn't fix them all, just the ones at the start
while (path.startsWith ("/."))
{
if (path.startsWith ("/../"))
{
path = path.substring (3);
modified = true;
}
else if (path.startsWith ("/./") || path.startsWith("/."))
{
path = path.substring (2);
modified = true;
}
else
break;
}
}
// fix backslashes
while (-1 != (index = path.indexOf ("/\\")))
{
path = path.substring (0, index + 1) + path.substring (index + 2);
modified = true;
}
if (modified)
url = new URL (url, path);
return (url);
}
/**
* Create an absolute URL from a relative link.
* @param link The reslative portion of a URL.
* @return The fully qualified URL or the original link if it was absolute
* already or a failure occured.
*/
public String getAbsoluteURL (String link)
{
return (getAbsoluteURL (link, false));
}
/**
* Create an absolute URL from a relative link.
* @param link The reslative portion of a URL.
* @param strict If <code>true</code> a link starting with '?' is handled
* according to <a href="http://www.ietf.org/rfc/rfc2396.txt">RFC 2396</a>,
* otherwise the common interpretation of a query appended to the base
* is used instead.
* @return The fully qualified URL or the original link if it was absolute
* already or a failure occured.
*/
public String getAbsoluteURL (String link, boolean strict)
{
String base;
URL url;
String ret;
if ((null == link) || ("".equals (link)))
ret = "";
else
try
{
base = getBaseUrl ();
if (null == base)
base = getUrl ();
if (null == base)
ret = link;
else
{
url = constructUrl (link, base, strict);
ret = url.toExternalForm ();
}
}
catch (MalformedURLException murle)
{
ret = link;
}
return (ret);
}
/**
* Get the line number for a cursor.
* @param cursor The character offset into the page.
* @return The line number the character is in.
*/
public int row (Cursor cursor)
{
return (mIndex.row (cursor));
}
/**
* Get the line number for a cursor.
* @param position The character offset into the page.
* @return The line number the character is in.
*/
public int row (int position)
{
return (mIndex.row (position));
}
/**
* Get the column number for a cursor.
* @param cursor The character offset into the page.
* @return The character offset into the line this cursor is on.
*/
public int column (Cursor cursor)
{
return (mIndex.column (cursor));
}
/**
* Get the column number for a cursor.
* @param position The character offset into the page.
* @return The character offset into the line this cursor is on.
*/
public int column (int position)
{
return (mIndex.column (position));
}
/**
* Get the text identified by the given limits.
* @param start The starting position, zero based.
* @param end The ending position
* (exclusive, i.e. the character at the ending position is not included),
* zero based.
* @return The text from <code>start</code> to <code>end</code>.
* @see #getText(StringBuffer, int, int)
* @exception IllegalArgumentException If an attempt is made to get
* characters ahead of the current source offset (character position).
*/
public String getText (int start, int end)
throws
IllegalArgumentException
{
String ret;
try
{
ret = mSource.getString (start, end - start);
}
catch (IOException ioe)
{
throw new IllegalArgumentException (
"can't get the "
+ (end - start)
+ "characters at position "
+ start
+ " - "
+ ioe.getMessage ());
}
return (ret);
}
/**
* Put the text identified by the given limits into the given buffer.
* @param buffer The accumulator for the characters.
* @param start The starting position, zero based.
* @param end The ending position
* (exclusive, i.e. the character at the ending position is not included),
* zero based.
* @exception IllegalArgumentException If an attempt is made to get
* characters ahead of the current source offset (character position).
*/
public void getText (StringBuffer buffer, int start, int end)
throws
IllegalArgumentException
{
int length;
if ((mSource.offset () < start) || (mSource.offset () < end))
throw new IllegalArgumentException (
"attempt to extract future characters from source"
+ start + "|" + end + " > " + mSource.offset ());
if (end < start)
{
length = end;
end = start;
start = length;
}
length = end - start;
try
{
mSource.getCharacters (buffer, start, length);
}
catch (IOException ioe)
{
throw new IllegalArgumentException (
"can't get the "
+ (end - start)
+ "characters at position "
+ start
+ " - "
+ ioe.getMessage ());
}
}
/**
* Get all text read so far from the source.
* @return The text from the source.
* @see #getText(StringBuffer)
*/
public String getText ()
{
return (getText (0, mSource.offset ()));
}
/**
* Put all text read so far from the source into the given buffer.
* @param buffer The accumulator for the characters.
* @see #getText(StringBuffer,int,int)
*/
public void getText (StringBuffer buffer)
{
getText (buffer, 0, mSource.offset ());
}
/**
* Put the text identified by the given limits into the given array at the specified offset.
* @param array The array of characters.
* @param offset The starting position in the array where characters are to be placed.
* @param start The starting position, zero based.
* @param end The ending position
* (exclusive, i.e. the character at the ending position is not included),
* zero based.
* @exception IllegalArgumentException If an attempt is made to get
* characters ahead of the current source offset (character position).
*/
public void getText (char[] array, int offset, int start, int end)
throws
IllegalArgumentException
{
int length;
if ((mSource.offset () < start) || (mSource.offset () < end))
throw new IllegalArgumentException ("attempt to extract future characters from source");
if (end < start)
{ // swap
length = end;
end = start;
start = length;
}
length = end - start;
try
{
mSource.getCharacters (array, offset, start, end);
}
catch (IOException ioe)
{
throw new IllegalArgumentException (
"can't get the "
+ (end - start)
+ "characters at position "
+ start
+ " - "
+ ioe.getMessage ());
}
}
/**
* Get the text line the position of the cursor lies on.
* @param cursor The position to calculate for.
* @return The contents of the URL or file corresponding to the line number
* containing the cursor position.
*/
public String getLine (Cursor cursor)
{
int line;
int size;
int start;
int end;
line = row (cursor);
size = mIndex.size ();
if (line < size)
{
start = mIndex.elementAt (line);
line++;
if (line <= size)
end = mIndex.elementAt (line);
else
end = mSource.offset ();
}
else // current line
{
start = mIndex.elementAt (line - 1);
end = mSource.offset ();
}
return (getText (start, end));
}
/**
* Get the text line the position of the cursor lies on.
* @param position The position to calculate for.
* @return The contents of the URL or file corresponding to the line number
* containg the cursor position.
*/
public String getLine (int position)
{
return (getLine (new Cursor (this, position)));
}
/**
* Display some of this page as a string.
* @return The last few characters the source read in.
*/
public String toString ()
{
StringBuffer buffer;
int start;
String ret;
if (mSource.offset () > 0)
{
buffer = new StringBuffer (43);
start = mSource.offset () - 40;
if (0 > start)
start = 0;
else
buffer.append ("...");
getText (buffer, start, mSource.offset ());
ret = buffer.toString ();
}
else
ret = super.toString ();
return (ret);
}
}