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* DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
*
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* under the terms of the GNU General Public License version 2 only, as
* published by the Free Software Foundation. Oracle designates this
* particular file as subject to the "Classpath" exception as provided
* by Oracle in the LICENSE file that accompanied this code.
*
* This code 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
* version 2 for more details (a copy is included in the LICENSE file that
* accompanied this code).
*
* You should have received a copy of the GNU General Public License version
* 2 along with this work; if not, write to the Free Software Foundation,
* Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
*
* Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
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*/
package javax.swing.text;
/**
* Represents a location within a document. It is intended to abstract away
* implementation details of the document and enable specification of
* positions within the document that are capable of tracking of change as
* the document is edited.
* <p>
* A {@code Position} object points at a location between two characters.
* As the surrounding content is altered, the {@code Position} object
* adjusts its offset automatically to reflect the changes. If content is
* inserted or removed before the {@code Position} object's location, then the
* {@code Position} increments or decrements its offset, respectively,
* so as to point to the same location. If a portion of the document is removed
* that contains a {@code Position}'s offset, then the {@code Position}'s
* offset becomes that of the beginning of the removed region. For example, if
* a {@code Position} has an offset of 5 and the region 2-10 is removed, then
* the {@code Position}'s offset becomes 2.
* <p>
* {@code Position} with an offset of 0 is a special case. It never changes its
* offset while document content is altered.
*
* @author Timothy Prinzing
*/
public interface Position {
/**
* Fetches the current offset within the document.
*
* @return the offset >= 0
*/
public int getOffset();
/**
* A typesafe enumeration to indicate bias to a position
* in the model. A position indicates a location between
* two characters. The bias can be used to indicate an
* interest toward one of the two sides of the position
* in boundary conditions where a simple offset is
* ambiguous.
*/
public static final class Bias {
/**
* Indicates to bias toward the next character
* in the model.
*/
public static final Bias Forward = new Bias("Forward");
/**
* Indicates a bias toward the previous character
* in the model.
*/
public static final Bias Backward = new Bias("Backward");
/**
* string representation
*/
public String toString() {
return name;
}
private Bias(String name) {
this.name = name;
}
private String name;
}
}