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	/*
	* Copyright (c) 1996, 2013, Oracle and/or its affiliates. All rights reserved.
	* DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
	*
	* This code is free software; you can redistribute it and/or modify it
	* 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
	* or visit www.oracle.com if you need additional information or have any
	* questions.
	*/

	/*
	* (C) Copyright Taligent, Inc. 1996 - All Rights Reserved
	* (C) Copyright IBM Corp. 1996 - All Rights Reserved
	*
	* The original version of this source code and documentation is copyrighted
	* and owned by Taligent, Inc., a wholly-owned subsidiary of IBM. These
	* materials are provided under terms of a License Agreement between Taligent
	* and Sun. This technology is protected by multiple US and International
	* patents. This notice and attribution to Taligent may not be removed.
	* Taligent is a registered trademark of Taligent, Inc.
	*
	*/

	package java.text;

	/**
	* <code>FieldPosition</code> is a simple class used by <code>Format</code>
	* and its subclasses to identify fields in formatted output. Fields can
	* be identified in two ways:
	* <ul>
	* <li>By an integer constant, whose names typically end with
	* <code>_FIELD</code>. The constants are defined in the various
	* subclasses of <code>Format</code>.
	* <li>By a <code>Format.Field</code> constant, see <code>ERA_FIELD</code>
	* and its friends in <code>DateFormat</code> for an example.
	* </ul>
	* <p>
	* <code>FieldPosition</code> keeps track of the position of the
	* field within the formatted output with two indices: the index
	* of the first character of the field and the index of the last
	* character of the field.
	*
	* <p>
	* One version of the <code>format</code> method in the various
	* <code>Format</code> classes requires a <code>FieldPosition</code>
	* object as an argument. You use this <code>format</code> method
	* to perform partial formatting or to get information about the
	* formatted output (such as the position of a field).
	*
	* <p>
	* If you are interested in the positions of all attributes in the
	* formatted string use the <code>Format</code> method
	* <code>formatToCharacterIterator</code>.
	*
	* @author Mark Davis
	* @see java.text.Format
	*/
	public class FieldPosition {

	/**
	* Input: Desired field to determine start and end offsets for.
	* The meaning depends on the subclass of Format.
	*/
	int field = 0;

	/**
	* Output: End offset of field in text.
	* If the field does not occur in the text, 0 is returned.
	*/
	int endIndex = 0;

	/**
	* Output: Start offset of field in text.
	* If the field does not occur in the text, 0 is returned.
	*/
	int beginIndex = 0;

	/**
	* Desired field this FieldPosition is for.
	*/
	private Format.Field attribute;

	/**
	* Creates a FieldPosition object for the given field. Fields are
	* identified by constants, whose names typically end with _FIELD,
	* in the various subclasses of Format.
	*
	* @param field the field identifier
	* @see java.text.NumberFormat#INTEGER_FIELD
	* @see java.text.NumberFormat#FRACTION_FIELD
	* @see java.text.DateFormat#YEAR_FIELD
	* @see java.text.DateFormat#MONTH_FIELD
	*/
	public FieldPosition(int field) {
	this.field = field;
	}

	/**
	* Creates a FieldPosition object for the given field constant. Fields are
	* identified by constants defined in the various <code>Format</code>
	* subclasses. This is equivalent to calling
	* <code>new FieldPosition(attribute, -1)</code>.
	*
	* @param attribute Format.Field constant identifying a field
	* @since 1.4
	*/
	public FieldPosition(Format.Field attribute) {
	this(attribute, -1);
	}

	/**
	* Creates a <code>FieldPosition</code> object for the given field.
	* The field is identified by an attribute constant from one of the
	* <code>Field</code> subclasses as well as an integer field ID
	* defined by the <code>Format</code> subclasses. <code>Format</code>
	* subclasses that are aware of <code>Field</code> should give precedence
	* to <code>attribute</code> and ignore <code>fieldID</code> if
	* <code>attribute</code> is not null. However, older <code>Format</code>
	* subclasses may not be aware of <code>Field</code> and rely on
	* <code>fieldID</code>. If the field has no corresponding integer
	* constant, <code>fieldID</code> should be -1.
	*
	* @param attribute Format.Field constant identifying a field
	* @param fieldID integer constant identifying a field
	* @since 1.4
	*/
	public FieldPosition(Format.Field attribute, int fieldID) {
	this.attribute = attribute;
	this.field = fieldID;
	}

	/**
	* Returns the field identifier as an attribute constant
	* from one of the <code>Field</code> subclasses. May return null if
	* the field is specified only by an integer field ID.
	*
	* @return Identifier for the field
	* @since 1.4
	*/
	public Format.Field getFieldAttribute() {
	return attribute;
	}

	/**
	* Retrieves the field identifier.
	*
	* @return the field identifier
	*/
	public int getField() {
	return field;
	}

	/**
	* Retrieves the index of the first character in the requested field.
	*
	* @return the begin index
	*/
	public int getBeginIndex() {
	return beginIndex;
	}

	/**
	* Retrieves the index of the character following the last character in the
	* requested field.
	*
	* @return the end index
	*/
	public int getEndIndex() {
	return endIndex;
	}

	/**
	* Sets the begin index. For use by subclasses of Format.
	*
	* @param bi the begin index
	* @since 1.2
	*/
	public void setBeginIndex(int bi) {
	beginIndex = bi;
	}

	/**
	* Sets the end index. For use by subclasses of Format.
	*
	* @param ei the end index
	* @since 1.2
	*/
	public void setEndIndex(int ei) {
	endIndex = ei;
	}

	/**
	* Returns a <code>Format.FieldDelegate</code> instance that is associated
	* with the FieldPosition. When the delegate is notified of the same
	* field the FieldPosition is associated with, the begin/end will be
	* adjusted.
	*/
	Format.FieldDelegate getFieldDelegate() {
	return new Delegate();
	}

	/**
	* Overrides equals
	*/
	public boolean equals(Object obj)
	{
	if (obj == null) return false;
	if (!(obj instanceof FieldPosition))
	return false;
	FieldPosition other = (FieldPosition) obj;
	if (attribute == null) {
	if (other.attribute != null) {
	return false;
	}
	}
	else if (!attribute.equals(other.attribute)) {
	return false;
	}
	return (beginIndex == other.beginIndex
	&& endIndex == other.endIndex
	&& field == other.field);
	}

	/**
	* Returns a hash code for this FieldPosition.
	* @return a hash code value for this object
	*/
	public int hashCode() {
	return (field << 24) \| (beginIndex << 16) \| endIndex;
	}

	/**
	* Return a string representation of this FieldPosition.
	* @return a string representation of this object
	*/
	public String toString() {
	return getClass().getName() +
	"[field=" + field + ",attribute=" + attribute +
	",beginIndex=" + beginIndex +
	",endIndex=" + endIndex + ']';
	}


	/**
	* Return true if the receiver wants a <code>Format.Field</code> value and
	* <code>attribute</code> is equal to it.
	*/
	private boolean matchesField(Format.Field attribute) {
	if (this.attribute != null) {
	return this.attribute.equals(attribute);
	}
	return false;
	}

	/**
	* Return true if the receiver wants a <code>Format.Field</code> value and
	* <code>attribute</code> is equal to it, or true if the receiver
	* represents an inteter constant and <code>field</code> equals it.
	*/
	private boolean matchesField(Format.Field attribute, int field) {
	if (this.attribute != null) {
	return this.attribute.equals(attribute);
	}
	return (field == this.field);
	}


	/**
	* An implementation of FieldDelegate that will adjust the begin/end
	* of the FieldPosition if the arguments match the field of
	* the FieldPosition.
	*/
	private class Delegate implements Format.FieldDelegate {
	/**
	* Indicates whether the field has been encountered before. If this
	* is true, and <code>formatted</code> is invoked, the begin/end
	* are not updated.
	*/
	private boolean encounteredField;

	public void formatted(Format.Field attr, Object value, int start,
	int end, StringBuffer buffer) {
	if (!encounteredField && matchesField(attr)) {
	setBeginIndex(start);
	setEndIndex(end);
	encounteredField = (start != end);
	}
	}

	public void formatted(int fieldID, Format.Field attr, Object value,
	int start, int end, StringBuffer buffer) {
	if (!encounteredField && matchesField(attr, fieldID)) {
	setBeginIndex(start);
	setEndIndex(end);
	encounteredField = (start != end);
	}
	}
	}
	}

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