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	/*
	* Copyright (c) 1997, 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.
	*/

	package java.awt;

	import java.beans.ConstructorProperties;

	import java.lang.annotation.Native;

	/**
	* The <code>BasicStroke</code> class defines a basic set of rendering
	* attributes for the outlines of graphics primitives, which are rendered
	* with a {@link Graphics2D} object that has its Stroke attribute set to
	* this <code>BasicStroke</code>.
	* The rendering attributes defined by <code>BasicStroke</code> describe
	* the shape of the mark made by a pen drawn along the outline of a
	* {@link Shape} and the decorations applied at the ends and joins of
	* path segments of the <code>Shape</code>.
	* These rendering attributes include:
	* <dl>
	* <dt><i>width</i>
	* <dd>The pen width, measured perpendicularly to the pen trajectory.
	* <dt><i>end caps</i>
	* <dd>The decoration applied to the ends of unclosed subpaths and
	* dash segments. Subpaths that start and end on the same point are
	* still considered unclosed if they do not have a CLOSE segment.
	* See {@link java.awt.geom.PathIterator#SEG_CLOSE SEG_CLOSE}
	* for more information on the CLOSE segment.
	* The three different decorations are: {@link #CAP_BUTT},
	* {@link #CAP_ROUND}, and {@link #CAP_SQUARE}.
	* <dt><i>line joins</i>
	* <dd>The decoration applied at the intersection of two path segments
	* and at the intersection of the endpoints of a subpath that is closed
	* using {@link java.awt.geom.PathIterator#SEG_CLOSE SEG_CLOSE}.
	* The three different decorations are: {@link #JOIN_BEVEL},
	* {@link #JOIN_MITER}, and {@link #JOIN_ROUND}.
	* <dt><i>miter limit</i>
	* <dd>The limit to trim a line join that has a JOIN_MITER decoration.
	* A line join is trimmed when the ratio of miter length to stroke
	* width is greater than the miterlimit value. The miter length is
	* the diagonal length of the miter, which is the distance between
	* the inside corner and the outside corner of the intersection.
	* The smaller the angle formed by two line segments, the longer
	* the miter length and the sharper the angle of intersection. The
	* default miterlimit value of 10.0f causes all angles less than
	* 11 degrees to be trimmed. Trimming miters converts
	* the decoration of the line join to bevel.
	* <dt><i>dash attributes</i>
	* <dd>The definition of how to make a dash pattern by alternating
	* between opaque and transparent sections.
	* </dl>
	* All attributes that specify measurements and distances controlling
	* the shape of the returned outline are measured in the same
	* coordinate system as the original unstroked <code>Shape</code>
	* argument. When a <code>Graphics2D</code> object uses a
	* <code>Stroke</code> object to redefine a path during the execution
	* of one of its <code>draw</code> methods, the geometry is supplied
	* in its original form before the <code>Graphics2D</code> transform
	* attribute is applied. Therefore, attributes such as the pen width
	* are interpreted in the user space coordinate system of the
	* <code>Graphics2D</code> object and are subject to the scaling and
	* shearing effects of the user-space-to-device-space transform in that
	* particular <code>Graphics2D</code>.
	* For example, the width of a rendered shape's outline is determined
	* not only by the width attribute of this <code>BasicStroke</code>,
	* but also by the transform attribute of the
	* <code>Graphics2D</code> object. Consider this code:
	* <blockquote><tt>
	* // sets the Graphics2D object's Transform attribute
	* g2d.scale(10, 10);
	* // sets the Graphics2D object's Stroke attribute
	* g2d.setStroke(new BasicStroke(1.5f));
	* </tt></blockquote>
	* Assuming there are no other scaling transforms added to the
	* <code>Graphics2D</code> object, the resulting line
	* will be approximately 15 pixels wide.
	* As the example code demonstrates, a floating-point line
	* offers better precision, especially when large transforms are
	* used with a <code>Graphics2D</code> object.
	* When a line is diagonal, the exact width depends on how the
	* rendering pipeline chooses which pixels to fill as it traces the
	* theoretical widened outline. The choice of which pixels to turn
	* on is affected by the antialiasing attribute because the
	* antialiasing rendering pipeline can choose to color
	* partially-covered pixels.
	* <p>
	* For more information on the user space coordinate system and the
	* rendering process, see the <code>Graphics2D</code> class comments.
	* @see Graphics2D
	* @author Jim Graham
	*/
	public class BasicStroke implements Stroke {

	/**
	* Joins path segments by extending their outside edges until
	* they meet.
	*/
	@Native public final static int JOIN_MITER = 0;

	/**
	* Joins path segments by rounding off the corner at a radius
	* of half the line width.
	*/
	@Native public final static int JOIN_ROUND = 1;

	/**
	* Joins path segments by connecting the outer corners of their
	* wide outlines with a straight segment.
	*/
	@Native public final static int JOIN_BEVEL = 2;

	/**
	* Ends unclosed subpaths and dash segments with no added
	* decoration.
	*/
	@Native public final static int CAP_BUTT = 0;

	/**
	* Ends unclosed subpaths and dash segments with a round
	* decoration that has a radius equal to half of the width
	* of the pen.
	*/
	@Native public final static int CAP_ROUND = 1;

	/**
	* Ends unclosed subpaths and dash segments with a square
	* projection that extends beyond the end of the segment
	* to a distance equal to half of the line width.
	*/
	@Native public final static int CAP_SQUARE = 2;

	float width;

	int join;
	int cap;
	float miterlimit;

	float dash[];
	float dash_phase;

	/**
	* Constructs a new <code>BasicStroke</code> with the specified
	* attributes.
	* @param width the width of this <code>BasicStroke</code>. The
	* width must be greater than or equal to 0.0f. If width is
	* set to 0.0f, the stroke is rendered as the thinnest
	* possible line for the target device and the antialias
	* hint setting.
	* @param cap the decoration of the ends of a <code>BasicStroke</code>
	* @param join the decoration applied where path segments meet
	* @param miterlimit the limit to trim the miter join. The miterlimit
	* must be greater than or equal to 1.0f.
	* @param dash the array representing the dashing pattern
	* @param dash_phase the offset to start the dashing pattern
	* @throws IllegalArgumentException if <code>width</code> is negative
	* @throws IllegalArgumentException if <code>cap</code> is not either
	* CAP_BUTT, CAP_ROUND or CAP_SQUARE
	* @throws IllegalArgumentException if <code>miterlimit</code> is less
	* than 1 and <code>join</code> is JOIN_MITER
	* @throws IllegalArgumentException if <code>join</code> is not
	* either JOIN_ROUND, JOIN_BEVEL, or JOIN_MITER
	* @throws IllegalArgumentException if <code>dash_phase</code>
	* is negative and <code>dash</code> is not <code>null</code>
	* @throws IllegalArgumentException if the length of
	* <code>dash</code> is zero
	* @throws IllegalArgumentException if dash lengths are all zero.
	*/
	@ConstructorProperties({ "lineWidth", "endCap", "lineJoin", "miterLimit", "dashArray", "dashPhase" })
	public BasicStroke(float width, int cap, int join, float miterlimit,
	float dash[], float dash_phase) {
	if (width < 0.0f) {
	throw new IllegalArgumentException("negative width");
	}
	if (cap != CAP_BUTT && cap != CAP_ROUND && cap != CAP_SQUARE) {
	throw new IllegalArgumentException("illegal end cap value");
	}
	if (join == JOIN_MITER) {
	if (miterlimit < 1.0f) {
	throw new IllegalArgumentException("miter limit < 1");
	}
	} else if (join != JOIN_ROUND && join != JOIN_BEVEL) {
	throw new IllegalArgumentException("illegal line join value");
	}
	if (dash != null) {
	if (dash_phase < 0.0f) {
	throw new IllegalArgumentException("negative dash phase");
	}
	boolean allzero = true;
	for (int i = 0; i < dash.length; i++) {
	float d = dash[i];
	if (d > 0.0) {
	allzero = false;
	} else if (d < 0.0) {
	throw new IllegalArgumentException("negative dash length");
	}
	}
	if (allzero) {
	throw new IllegalArgumentException("dash lengths all zero");
	}
	}
	this.width = width;
	this.cap = cap;
	this.join = join;
	this.miterlimit = miterlimit;
	if (dash != null) {
	this.dash = (float []) dash.clone();
	}
	this.dash_phase = dash_phase;
	}

	/**
	* Constructs a solid <code>BasicStroke</code> with the specified
	* attributes.
	* @param width the width of the <code>BasicStroke</code>
	* @param cap the decoration of the ends of a <code>BasicStroke</code>
	* @param join the decoration applied where path segments meet
	* @param miterlimit the limit to trim the miter join
	* @throws IllegalArgumentException if <code>width</code> is negative
	* @throws IllegalArgumentException if <code>cap</code> is not either
	* CAP_BUTT, CAP_ROUND or CAP_SQUARE
	* @throws IllegalArgumentException if <code>miterlimit</code> is less
	* than 1 and <code>join</code> is JOIN_MITER
	* @throws IllegalArgumentException if <code>join</code> is not
	* either JOIN_ROUND, JOIN_BEVEL, or JOIN_MITER
	*/
	public BasicStroke(float width, int cap, int join, float miterlimit) {
	this(width, cap, join, miterlimit, null, 0.0f);
	}

	/**
	* Constructs a solid <code>BasicStroke</code> with the specified
	* attributes. The <code>miterlimit</code> parameter is
	* unnecessary in cases where the default is allowable or the
	* line joins are not specified as JOIN_MITER.
	* @param width the width of the <code>BasicStroke</code>
	* @param cap the decoration of the ends of a <code>BasicStroke</code>
	* @param join the decoration applied where path segments meet
	* @throws IllegalArgumentException if <code>width</code> is negative
	* @throws IllegalArgumentException if <code>cap</code> is not either
	* CAP_BUTT, CAP_ROUND or CAP_SQUARE
	* @throws IllegalArgumentException if <code>join</code> is not
	* either JOIN_ROUND, JOIN_BEVEL, or JOIN_MITER
	*/
	public BasicStroke(float width, int cap, int join) {
	this(width, cap, join, 10.0f, null, 0.0f);
	}

	/**
	* Constructs a solid <code>BasicStroke</code> with the specified
	* line width and with default values for the cap and join
	* styles.
	* @param width the width of the <code>BasicStroke</code>
	* @throws IllegalArgumentException if <code>width</code> is negative
	*/
	public BasicStroke(float width) {
	this(width, CAP_SQUARE, JOIN_MITER, 10.0f, null, 0.0f);
	}

	/**
	* Constructs a new <code>BasicStroke</code> with defaults for all
	* attributes.
	* The default attributes are a solid line of width 1.0, CAP_SQUARE,
	* JOIN_MITER, a miter limit of 10.0.
	*/
	public BasicStroke() {
	this(1.0f, CAP_SQUARE, JOIN_MITER, 10.0f, null, 0.0f);
	}


	/**
	* Returns a <code>Shape</code> whose interior defines the
	* stroked outline of a specified <code>Shape</code>.
	* @param s the <code>Shape</code> boundary be stroked
	* @return the <code>Shape</code> of the stroked outline.
	*/
	public Shape createStrokedShape(Shape s) {
	sun.java2d.pipe.RenderingEngine re =
	sun.java2d.pipe.RenderingEngine.getInstance();
	return re.createStrokedShape(s, width, cap, join, miterlimit,
	dash, dash_phase);
	}

	/**
	* Returns the line width. Line width is represented in user space,
	* which is the default-coordinate space used by Java 2D. See the
	* <code>Graphics2D</code> class comments for more information on
	* the user space coordinate system.
	* @return the line width of this <code>BasicStroke</code>.
	* @see Graphics2D
	*/
	public float getLineWidth() {
	return width;
	}

	/**
	* Returns the end cap style.
	* @return the end cap style of this <code>BasicStroke</code> as one
	* of the static <code>int</code> values that define possible end cap
	* styles.
	*/
	public int getEndCap() {
	return cap;
	}

	/**
	* Returns the line join style.
	* @return the line join style of the <code>BasicStroke</code> as one
	* of the static <code>int</code> values that define possible line
	* join styles.
	*/
	public int getLineJoin() {
	return join;
	}

	/**
	* Returns the limit of miter joins.
	* @return the limit of miter joins of the <code>BasicStroke</code>.
	*/
	public float getMiterLimit() {
	return miterlimit;
	}

	/**
	* Returns the array representing the lengths of the dash segments.
	* Alternate entries in the array represent the user space lengths
	* of the opaque and transparent segments of the dashes.
	* As the pen moves along the outline of the <code>Shape</code>
	* to be stroked, the user space
	* distance that the pen travels is accumulated. The distance
	* value is used to index into the dash array.
	* The pen is opaque when its current cumulative distance maps
	* to an even element of the dash array and transparent otherwise.
	* @return the dash array.
	*/
	public float[] getDashArray() {
	if (dash == null) {
	return null;
	}

	return (float[]) dash.clone();
	}

	/**
	* Returns the current dash phase.
	* The dash phase is a distance specified in user coordinates that
	* represents an offset into the dashing pattern. In other words, the dash
	* phase defines the point in the dashing pattern that will correspond to
	* the beginning of the stroke.
	* @return the dash phase as a <code>float</code> value.
	*/
	public float getDashPhase() {
	return dash_phase;
	}

	/**
	* Returns the hashcode for this stroke.
	* @return a hash code for this stroke.
	*/
	public int hashCode() {
	int hash = Float.floatToIntBits(width);
	hash = hash * 31 + join;
	hash = hash * 31 + cap;
	hash = hash * 31 + Float.floatToIntBits(miterlimit);
	if (dash != null) {
	hash = hash * 31 + Float.floatToIntBits(dash_phase);
	for (int i = 0; i < dash.length; i++) {
	hash = hash * 31 + Float.floatToIntBits(dash[i]);
	}
	}
	return hash;
	}

	/**
	* Returns true if this BasicStroke represents the same
	* stroking operation as the given argument.
	*/
	/**
	* Tests if a specified object is equal to this <code>BasicStroke</code>
	* by first testing if it is a <code>BasicStroke</code> and then comparing
	* its width, join, cap, miter limit, dash, and dash phase attributes with
	* those of this <code>BasicStroke</code>.
	* @param obj the specified object to compare to this
	* <code>BasicStroke</code>
	* @return <code>true</code> if the width, join, cap, miter limit, dash, and
	* dash phase are the same for both objects;
	* <code>false</code> otherwise.
	*/
	public boolean equals(Object obj) {
	if (!(obj instanceof BasicStroke)) {
	return false;
	}

	BasicStroke bs = (BasicStroke) obj;
	if (width != bs.width) {
	return false;
	}

	if (join != bs.join) {
	return false;
	}

	if (cap != bs.cap) {
	return false;
	}

	if (miterlimit != bs.miterlimit) {
	return false;
	}

	if (dash != null) {
	if (dash_phase != bs.dash_phase) {
	return false;
	}

	if (!java.util.Arrays.equals(dash, bs.dash)) {
	return false;
	}
	}
	else if (bs.dash != null) {
	return false;
	}

	return true;
	}
	}

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