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	/*
	* Copyright (c) 1995, 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
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	* questions.
	*/

	package java.awt;

	/**
	* The <code>GridLayout</code> class is a layout manager that
	* lays out a container's components in a rectangular grid.
	* The container is divided into equal-sized rectangles,
	* and one component is placed in each rectangle.
	* For example, the following is an applet that lays out six buttons
	* into three rows and two columns:
	*
	* <hr><blockquote>
	* <pre>
	* import java.awt.*;
	* import java.applet.Applet;
	* public class ButtonGrid extends Applet {
	* public void init() {
	* setLayout(new GridLayout(3,2));
	* add(new Button("1"));
	* add(new Button("2"));
	* add(new Button("3"));
	* add(new Button("4"));
	* add(new Button("5"));
	* add(new Button("6"));
	* }
	* }
	* </pre></blockquote><hr>
	* <p>
	* If the container's <code>ComponentOrientation</code> property is horizontal
	* and left-to-right, the above example produces the output shown in Figure 1.
	* If the container's <code>ComponentOrientation</code> property is horizontal
	* and right-to-left, the example produces the output shown in Figure 2.
	*
	* <table style="float:center" WIDTH=600 summary="layout">
	* <tr ALIGN=CENTER>
	* <td><img SRC="doc-files/GridLayout-1.gif"
	* alt="Shows 6 buttons in rows of 2. Row 1 shows buttons 1 then 2.
	* Row 2 shows buttons 3 then 4. Row 3 shows buttons 5 then 6.">
	* </td>
	*
	* <td ALIGN=CENTER><img SRC="doc-files/GridLayout-2.gif"
	* alt="Shows 6 buttons in rows of 2. Row 1 shows buttons 2 then 1.
	* Row 2 shows buttons 4 then 3. Row 3 shows buttons 6 then 5.">
	* </td>
	* </tr>
	*
	* <tr ALIGN=CENTER>
	* <td>Figure 1: Horizontal, Left-to-Right</td>
	*
	* <td>Figure 2: Horizontal, Right-to-Left</td>
	* </tr>
	* </table>
	* <p>
	* When both the number of rows and the number of columns have
	* been set to non-zero values, either by a constructor or
	* by the <tt>setRows</tt> and <tt>setColumns</tt> methods, the number of
	* columns specified is ignored. Instead, the number of
	* columns is determined from the specified number of rows
	* and the total number of components in the layout. So, for
	* example, if three rows and two columns have been specified
	* and nine components are added to the layout, they will
	* be displayed as three rows of three columns. Specifying
	* the number of columns affects the layout only when the
	* number of rows is set to zero.
	*
	* @author Arthur van Hoff
	* @since JDK1.0
	*/
	public class GridLayout implements LayoutManager, java.io.Serializable {
	/*
	* serialVersionUID
	*/
	private static final long serialVersionUID = -7411804673224730901L;

	/**
	* This is the horizontal gap (in pixels) which specifies the space
	* between columns. They can be changed at any time.
	* This should be a non-negative integer.
	*
	* @serial
	* @see #getHgap()
	* @see #setHgap(int)
	*/
	int hgap;
	/**
	* This is the vertical gap (in pixels) which specifies the space
	* between rows. They can be changed at any time.
	* This should be a non negative integer.
	*
	* @serial
	* @see #getVgap()
	* @see #setVgap(int)
	*/
	int vgap;
	/**
	* This is the number of rows specified for the grid. The number
	* of rows can be changed at any time.
	* This should be a non negative integer, where '0' means
	* 'any number' meaning that the number of Rows in that
	* dimension depends on the other dimension.
	*
	* @serial
	* @see #getRows()
	* @see #setRows(int)
	*/
	int rows;
	/**
	* This is the number of columns specified for the grid. The number
	* of columns can be changed at any time.
	* This should be a non negative integer, where '0' means
	* 'any number' meaning that the number of Columns in that
	* dimension depends on the other dimension.
	*
	* @serial
	* @see #getColumns()
	* @see #setColumns(int)
	*/
	int cols;

	/**
	* Creates a grid layout with a default of one column per component,
	* in a single row.
	* @since JDK1.1
	*/
	public GridLayout() {
	this(1, 0, 0, 0);
	}

	/**
	* Creates a grid layout with the specified number of rows and
	* columns. All components in the layout are given equal size.
	* <p>
	* One, but not both, of <code>rows</code> and <code>cols</code> can
	* be zero, which means that any number of objects can be placed in a
	* row or in a column.
	* @param rows the rows, with the value zero meaning
	* any number of rows.
	* @param cols the columns, with the value zero meaning
	* any number of columns.
	*/
	public GridLayout(int rows, int cols) {
	this(rows, cols, 0, 0);
	}

	/**
	* Creates a grid layout with the specified number of rows and
	* columns. All components in the layout are given equal size.
	* <p>
	* In addition, the horizontal and vertical gaps are set to the
	* specified values. Horizontal gaps are placed between each
	* of the columns. Vertical gaps are placed between each of
	* the rows.
	* <p>
	* One, but not both, of <code>rows</code> and <code>cols</code> can
	* be zero, which means that any number of objects can be placed in a
	* row or in a column.
	* <p>
	* All <code>GridLayout</code> constructors defer to this one.
	* @param rows the rows, with the value zero meaning
	* any number of rows
	* @param cols the columns, with the value zero meaning
	* any number of columns
	* @param hgap the horizontal gap
	* @param vgap the vertical gap
	* @exception IllegalArgumentException if the value of both
	* <code>rows</code> and <code>cols</code> is
	* set to zero
	*/
	public GridLayout(int rows, int cols, int hgap, int vgap) {
	if ((rows == 0) && (cols == 0)) {
	throw new IllegalArgumentException("rows and cols cannot both be zero");
	}
	this.rows = rows;
	this.cols = cols;
	this.hgap = hgap;
	this.vgap = vgap;
	}

	/**
	* Gets the number of rows in this layout.
	* @return the number of rows in this layout
	* @since JDK1.1
	*/
	public int getRows() {
	return rows;
	}

	/**
	* Sets the number of rows in this layout to the specified value.
	* @param rows the number of rows in this layout
	* @exception IllegalArgumentException if the value of both
	* <code>rows</code> and <code>cols</code> is set to zero
	* @since JDK1.1
	*/
	public void setRows(int rows) {
	if ((rows == 0) && (this.cols == 0)) {
	throw new IllegalArgumentException("rows and cols cannot both be zero");
	}
	this.rows = rows;
	}

	/**
	* Gets the number of columns in this layout.
	* @return the number of columns in this layout
	* @since JDK1.1
	*/
	public int getColumns() {
	return cols;
	}

	/**
	* Sets the number of columns in this layout to the specified value.
	* Setting the number of columns has no affect on the layout
	* if the number of rows specified by a constructor or by
	* the <tt>setRows</tt> method is non-zero. In that case, the number
	* of columns displayed in the layout is determined by the total
	* number of components and the number of rows specified.
	* @param cols the number of columns in this layout
	* @exception IllegalArgumentException if the value of both
	* <code>rows</code> and <code>cols</code> is set to zero
	* @since JDK1.1
	*/
	public void setColumns(int cols) {
	if ((cols == 0) && (this.rows == 0)) {
	throw new IllegalArgumentException("rows and cols cannot both be zero");
	}
	this.cols = cols;
	}

	/**
	* Gets the horizontal gap between components.
	* @return the horizontal gap between components
	* @since JDK1.1
	*/
	public int getHgap() {
	return hgap;
	}

	/**
	* Sets the horizontal gap between components to the specified value.
	* @param hgap the horizontal gap between components
	* @since JDK1.1
	*/
	public void setHgap(int hgap) {
	this.hgap = hgap;
	}

	/**
	* Gets the vertical gap between components.
	* @return the vertical gap between components
	* @since JDK1.1
	*/
	public int getVgap() {
	return vgap;
	}

	/**
	* Sets the vertical gap between components to the specified value.
	* @param vgap the vertical gap between components
	* @since JDK1.1
	*/
	public void setVgap(int vgap) {
	this.vgap = vgap;
	}

	/**
	* Adds the specified component with the specified name to the layout.
	* @param name the name of the component
	* @param comp the component to be added
	*/
	public void addLayoutComponent(String name, Component comp) {
	}

	/**
	* Removes the specified component from the layout.
	* @param comp the component to be removed
	*/
	public void removeLayoutComponent(Component comp) {
	}

	/**
	* Determines the preferred size of the container argument using
	* this grid layout.
	* <p>
	* The preferred width of a grid layout is the largest preferred
	* width of all of the components in the container times the number of
	* columns, plus the horizontal padding times the number of columns
	* minus one, plus the left and right insets of the target container.
	* <p>
	* The preferred height of a grid layout is the largest preferred
	* height of all of the components in the container times the number of
	* rows, plus the vertical padding times the number of rows minus one,
	* plus the top and bottom insets of the target container.
	*
	* @param parent the container in which to do the layout
	* @return the preferred dimensions to lay out the
	* subcomponents of the specified container
	* @see java.awt.GridLayout#minimumLayoutSize
	* @see java.awt.Container#getPreferredSize()
	*/
	public Dimension preferredLayoutSize(Container parent) {
	synchronized (parent.getTreeLock()) {
	Insets insets = parent.getInsets();
	int ncomponents = parent.getComponentCount();
	int nrows = rows;
	int ncols = cols;

	if (nrows > 0) {
	ncols = (ncomponents + nrows - 1) / nrows;
	} else {
	nrows = (ncomponents + ncols - 1) / ncols;
	}
	int w = 0;
	int h = 0;
	for (int i = 0 ; i < ncomponents ; i++) {
	Component comp = parent.getComponent(i);
	Dimension d = comp.getPreferredSize();
	if (w < d.width) {
	w = d.width;
	}
	if (h < d.height) {
	h = d.height;
	}
	}
	return new Dimension(insets.left + insets.right + ncolsw + (ncols-1)hgap,
	insets.top + insets.bottom + nrowsh + (nrows-1)vgap);
	}
	}

	/**
	* Determines the minimum size of the container argument using this
	* grid layout.
	* <p>
	* The minimum width of a grid layout is the largest minimum width
	* of all of the components in the container times the number of columns,
	* plus the horizontal padding times the number of columns minus one,
	* plus the left and right insets of the target container.
	* <p>
	* The minimum height of a grid layout is the largest minimum height
	* of all of the components in the container times the number of rows,
	* plus the vertical padding times the number of rows minus one, plus
	* the top and bottom insets of the target container.
	*
	* @param parent the container in which to do the layout
	* @return the minimum dimensions needed to lay out the
	* subcomponents of the specified container
	* @see java.awt.GridLayout#preferredLayoutSize
	* @see java.awt.Container#doLayout
	*/
	public Dimension minimumLayoutSize(Container parent) {
	synchronized (parent.getTreeLock()) {
	Insets insets = parent.getInsets();
	int ncomponents = parent.getComponentCount();
	int nrows = rows;
	int ncols = cols;

	if (nrows > 0) {
	ncols = (ncomponents + nrows - 1) / nrows;
	} else {
	nrows = (ncomponents + ncols - 1) / ncols;
	}
	int w = 0;
	int h = 0;
	for (int i = 0 ; i < ncomponents ; i++) {
	Component comp = parent.getComponent(i);
	Dimension d = comp.getMinimumSize();
	if (w < d.width) {
	w = d.width;
	}
	if (h < d.height) {
	h = d.height;
	}
	}
	return new Dimension(insets.left + insets.right + ncolsw + (ncols-1)hgap,
	insets.top + insets.bottom + nrowsh + (nrows-1)vgap);
	}
	}

	/**
	* Lays out the specified container using this layout.
	* <p>
	* This method reshapes the components in the specified target
	* container in order to satisfy the constraints of the
	* <code>GridLayout</code> object.
	* <p>
	* The grid layout manager determines the size of individual
	* components by dividing the free space in the container into
	* equal-sized portions according to the number of rows and columns
	* in the layout. The container's free space equals the container's
	* size minus any insets and any specified horizontal or vertical
	* gap. All components in a grid layout are given the same size.
	*
	* @param parent the container in which to do the layout
	* @see java.awt.Container
	* @see java.awt.Container#doLayout
	*/
	public void layoutContainer(Container parent) {
	synchronized (parent.getTreeLock()) {
	Insets insets = parent.getInsets();
	int ncomponents = parent.getComponentCount();
	int nrows = rows;
	int ncols = cols;
	boolean ltr = parent.getComponentOrientation().isLeftToRight();

	if (ncomponents == 0) {
	return;
	}
	if (nrows > 0) {
	ncols = (ncomponents + nrows - 1) / nrows;
	} else {
	nrows = (ncomponents + ncols - 1) / ncols;
	}
	// 4370316. To position components in the center we should:
	// 1. get an amount of extra space within Container
	// 2. incorporate half of that value to the left/top position
	// Note that we use trancating division for widthOnComponent
	// The reminder goes to extraWidthAvailable
	int totalGapsWidth = (ncols - 1) * hgap;
	int widthWOInsets = parent.width - (insets.left + insets.right);
	int widthOnComponent = (widthWOInsets - totalGapsWidth) / ncols;
	int extraWidthAvailable = (widthWOInsets - (widthOnComponent * ncols + totalGapsWidth)) / 2;

	int totalGapsHeight = (nrows - 1) * vgap;
	int heightWOInsets = parent.height - (insets.top + insets.bottom);
	int heightOnComponent = (heightWOInsets - totalGapsHeight) / nrows;
	int extraHeightAvailable = (heightWOInsets - (heightOnComponent * nrows + totalGapsHeight)) / 2;
	if (ltr) {
	for (int c = 0, x = insets.left + extraWidthAvailable; c < ncols ; c++, x += widthOnComponent + hgap) {
	for (int r = 0, y = insets.top + extraHeightAvailable; r < nrows ; r++, y += heightOnComponent + vgap) {
	int i = r * ncols + c;
	if (i < ncomponents) {
	parent.getComponent(i).setBounds(x, y, widthOnComponent, heightOnComponent);
	}
	}
	}
	} else {
	for (int c = 0, x = (parent.width - insets.right - widthOnComponent) - extraWidthAvailable; c < ncols ; c++, x -= widthOnComponent + hgap) {
	for (int r = 0, y = insets.top + extraHeightAvailable; r < nrows ; r++, y += heightOnComponent + vgap) {
	int i = r * ncols + c;
	if (i < ncomponents) {
	parent.getComponent(i).setBounds(x, y, widthOnComponent, heightOnComponent);
	}
	}
	}
	}
	}
	}

	/**
	* Returns the string representation of this grid layout's values.
	* @return a string representation of this grid layout
	*/
	public String toString() {
	return getClass().getName() + "[hgap=" + hgap + ",vgap=" + vgap +
	",rows=" + rows + ",cols=" + cols + "]";
	}
	}

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