298 lines
8.2 KiB
Java
298 lines
8.2 KiB
Java
/* Segment.java --
|
|
Copyright (C) 2002, 2004, 2006 Free Software Foundation, Inc.
|
|
|
|
This file is part of GNU Classpath.
|
|
|
|
GNU Classpath is free software; you can redistribute it and/or modify
|
|
it under the terms of the GNU General Public License as published by
|
|
the Free Software Foundation; either version 2, or (at your option)
|
|
any later version.
|
|
|
|
GNU Classpath 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 for more details.
|
|
|
|
You should have received a copy of the GNU General Public License
|
|
along with GNU Classpath; see the file COPYING. If not, write to the
|
|
Free Software Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA
|
|
02110-1301 USA.
|
|
|
|
Linking this library statically or dynamically with other modules is
|
|
making a combined work based on this library. Thus, the terms and
|
|
conditions of the GNU General Public License cover the whole
|
|
combination.
|
|
|
|
As a special exception, the copyright holders of this library give you
|
|
permission to link this library with independent modules to produce an
|
|
executable, regardless of the license terms of these independent
|
|
modules, and to copy and distribute the resulting executable under
|
|
terms of your choice, provided that you also meet, for each linked
|
|
independent module, the terms and conditions of the license of that
|
|
module. An independent module is a module which is not derived from
|
|
or based on this library. If you modify this library, you may extend
|
|
this exception to your version of the library, but you are not
|
|
obligated to do so. If you do not wish to do so, delete this
|
|
exception statement from your version. */
|
|
|
|
package javax.swing.text;
|
|
|
|
import java.text.CharacterIterator;
|
|
|
|
/**
|
|
* A text fragment represented by a sequence of characters stored in an array.
|
|
*/
|
|
public class Segment implements Cloneable, CharacterIterator
|
|
{
|
|
private boolean partialReturn;
|
|
|
|
/** The current index. */
|
|
private int current;
|
|
|
|
/** Storage for the characters (may contain additional characters). */
|
|
public char[] array;
|
|
|
|
/** The number of characters in the segment. */
|
|
public int count;
|
|
|
|
/** The offset of the first character in the segment. */
|
|
public int offset;
|
|
|
|
/**
|
|
* Creates a new <code>Segment</code>.
|
|
*/
|
|
public Segment()
|
|
{
|
|
// Nothing to do here.
|
|
}
|
|
|
|
/**
|
|
* Creates a new <code>Segment</code>.
|
|
*
|
|
* @param array the underlying character data.
|
|
* @param offset the offset of the first character in the segment.
|
|
* @param count the number of characters in the segment.
|
|
*/
|
|
public Segment(char[] array, int offset, int count)
|
|
{
|
|
this.array = array;
|
|
this.offset = offset;
|
|
this.count = count;
|
|
}
|
|
|
|
/**
|
|
* Clones the segment (note that the underlying character array is not cloned,
|
|
* just the reference to it).
|
|
*
|
|
* @return A clone of the segment.
|
|
*/
|
|
public Object clone()
|
|
{
|
|
try
|
|
{
|
|
return super.clone();
|
|
}
|
|
catch (CloneNotSupportedException e)
|
|
{
|
|
return null;
|
|
}
|
|
}
|
|
|
|
/**
|
|
* Returns the character at the current index. If the segment consists of
|
|
* zero characters, or the current index has passed the end of the
|
|
* characters in the segment, this method returns {@link #DONE}.
|
|
*
|
|
* @return The character at the current index.
|
|
*/
|
|
public char current()
|
|
{
|
|
if (count == 0
|
|
|| current >= getEndIndex())
|
|
return DONE;
|
|
|
|
return array[current];
|
|
}
|
|
|
|
/**
|
|
* Sets the current index to the first character in the segment and returns
|
|
* that character. If the segment contains zero characters, this method
|
|
* returns {@link #DONE}.
|
|
*
|
|
* @return The first character in the segment, or {@link #DONE} if the
|
|
* segment contains zero characters.
|
|
*/
|
|
public char first()
|
|
{
|
|
if (count == 0)
|
|
return DONE;
|
|
|
|
current = getBeginIndex();
|
|
return array[current];
|
|
}
|
|
|
|
/**
|
|
* Returns the index of the first character in the segment.
|
|
*
|
|
* @return The index of the first character.
|
|
*/
|
|
public int getBeginIndex()
|
|
{
|
|
return offset;
|
|
}
|
|
|
|
/**
|
|
* Returns the end index for the segment (one position beyond the last
|
|
* character in the segment - note that this can be outside the range of the
|
|
* underlying character array).
|
|
*
|
|
* @return The end index for the segment.
|
|
*/
|
|
public int getEndIndex()
|
|
{
|
|
return offset + count;
|
|
}
|
|
|
|
/**
|
|
* Returns the index of the current character in the segment.
|
|
*
|
|
* @return The index of the current character.
|
|
*/
|
|
public int getIndex()
|
|
{
|
|
return current;
|
|
}
|
|
|
|
/**
|
|
* Sets the current index to point to the last character in the segment and
|
|
* returns that character. If the segment contains zero characters, the
|
|
* current index is set to {@link #getEndIndex()} and this method returns
|
|
* {@link #DONE}.
|
|
*
|
|
* @return The last character in the segment, or {@link #DONE} if the
|
|
* segment contains zero characters.
|
|
*/
|
|
public char last()
|
|
{
|
|
if (count == 0)
|
|
{
|
|
current = getEndIndex();
|
|
return DONE;
|
|
}
|
|
|
|
current = getEndIndex() - 1;
|
|
return array[current];
|
|
}
|
|
|
|
/**
|
|
* Sets the current index to point to the next character in the segment and
|
|
* returns that character. If the next character position is past the end of
|
|
* the segment, the index is set to {@link #getEndIndex()} and the method
|
|
* returns {@link #DONE}. If the segment contains zero characters, this
|
|
* method returns {@link #DONE}.
|
|
*
|
|
* @return The next character in the segment or {@link #DONE} (if the next
|
|
* character position is past the end of the segment or if the
|
|
* segment contains zero characters).
|
|
*/
|
|
public char next()
|
|
{
|
|
if (count == 0)
|
|
return DONE;
|
|
|
|
if ((current + 1) >= getEndIndex())
|
|
{
|
|
current = getEndIndex();
|
|
return DONE;
|
|
}
|
|
|
|
current++;
|
|
return array[current];
|
|
}
|
|
|
|
/**
|
|
* Sets the current index to point to the previous character in the segment
|
|
* and returns that character. If the current index is equal to
|
|
* {@link #getBeginIndex()}, or if the segment contains zero characters, this
|
|
* method returns {@link #DONE}.
|
|
*
|
|
* @return The previous character in the segment or {@link #DONE} (if the
|
|
* current character position is at the beginning of the segment or
|
|
* if the segment contains zero characters).
|
|
*/
|
|
public char previous()
|
|
{
|
|
if (count == 0
|
|
|| current == getBeginIndex())
|
|
return DONE;
|
|
|
|
current--;
|
|
return array[current];
|
|
}
|
|
|
|
/**
|
|
* Sets the current index and returns the character at that position (or
|
|
* {@link #DONE} if the index is equal to {@link #getEndIndex()}.
|
|
*
|
|
* @param position the current position.
|
|
*
|
|
* @return The character at the specified <code>position</code>, or
|
|
* {@link #DONE} if <code>position</code> is equal to
|
|
* {@link #getEndIndex()}.
|
|
*
|
|
* @throws IllegalArgumentException if <code>position</code> is not in the
|
|
* range {@link #getBeginIndex()} to {@link #getEndIndex()}.
|
|
*/
|
|
public char setIndex(int position)
|
|
{
|
|
if (position < getBeginIndex()
|
|
|| position > getEndIndex())
|
|
throw new IllegalArgumentException("position: " + position
|
|
+ ", beginIndex: " + getBeginIndex()
|
|
+ ", endIndex: " + getEndIndex()
|
|
+ ", text: " + toString());
|
|
|
|
current = position;
|
|
|
|
if (position == getEndIndex())
|
|
return DONE;
|
|
|
|
return array[current];
|
|
}
|
|
|
|
/**
|
|
* Returns a <code>String</code> containing the same characters as this
|
|
* <code>Segment</code>.
|
|
*
|
|
* @return A <code>String</code> containing the same characters as this
|
|
* <code>Segment</code>.
|
|
*/
|
|
public String toString()
|
|
{
|
|
return (array != null) ? new String(array, offset, count) : "";
|
|
}
|
|
|
|
/**
|
|
* Sets the partial return flag.
|
|
*
|
|
* @param p the new value of the flag.
|
|
*
|
|
* @since 1.4
|
|
*/
|
|
public void setPartialReturn(boolean p)
|
|
{
|
|
partialReturn = p;
|
|
}
|
|
|
|
/**
|
|
* Returns the partial return flag.
|
|
*
|
|
* @return The partial return flag.
|
|
* @since 1.4
|
|
*/
|
|
public boolean isPartialReturn()
|
|
{
|
|
return partialReturn;
|
|
}
|
|
}
|