JMeter example source code file (VerticalLayout.java)

This example JMeter source code file (VerticalLayout.java) is included in the DevDaily.com "Java Source Code Warehouse" project. The intent of this project is to help you "Learn Java by Example" ^TM.

Java - JMeter tags/keywords

awt, both, center, center, component, dimension, dimension, insets, io, left, right, serializable, top, top, verticallayout, verticallayout

The JMeter VerticalLayout.java source code

/*
 * Licensed to the Apache Software Foundation (ASF) under one or more
 * contributor license agreements.  See the NOTICE file distributed with
 * this work for additional information regarding copyright ownership.
 * The ASF licenses this file to You under the Apache License, Version 2.0
 * (the "License"); you may not use this file except in compliance with
 * the License.  You may obtain a copy of the License at
 *
 *   http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 *
 */

package org.apache.jorphan.gui.layout;

import java.awt.Component;
import java.awt.Container;
import java.awt.Dimension;
import java.awt.Insets;
import java.awt.LayoutManager;
import java.io.Serializable;

/**
 * A vertical layout manager similar to java.awt.FlowLayout. Like FlowLayout
 * components do not expand to fill available space except when the horizontal
 * alignment is <code>BOTH in which case components are stretched
 * horizontally. Unlike FlowLayout, components will not wrap to form another
 * column if there isn't enough space vertically. VerticalLayout can optionally
 * anchor components to the top or bottom of the display area or center them
 * between the top and bottom. Revision date 04 April 1999
 *
 * @version $Revision: 905024 $
 */
public class VerticalLayout implements LayoutManager, Serializable {
    private static final long serialVersionUID = 240L;

    /**
     * The horizontal alignment constant that designates centering. Also used to
     * designate center anchoring.
     */
    public final static int CENTER = 0;

    /**
     * The horizontal alignment constant that designates right justification.
     */
    public final static int RIGHT = 1;

    /**
     * The horizontal alignment constant that designates left justification.
     */
    public final static int LEFT = 2;

    /**
     * The horizontal alignment constant that designates stretching the
     * component horizontally.
     */
    public final static int BOTH = 3;

    /**
     * The anchoring constant that designates anchoring to the top of the
     * display area.
     */
    public final static int TOP = 1;

    /**
     * The anchoring constant that designates anchoring to the bottom of the
     * display area.
     */
    public final static int BOTTOM = 2;

    /** The vertical vgap between components...defaults to 5. */
    private int vgap;

    /** LEFT, RIGHT, CENTER or BOTH...how the components are justified. */
    private int alignment;

    /**
     * TOP, BOTTOM or CENTER ...where are the components positioned in an
     * overlarge space.
     */
    private int anchor;

    // Constructors
    /**
     * Constructs an instance of VerticalLayout with a vertical vgap of 5
     * pixels, horizontal centering and anchored to the top of the display area.
     */
    public VerticalLayout() {
        this(5, CENTER, TOP);
    }

    /**
     * Constructs a VerticalLayout instance with horizontal centering, anchored
     * to the top with the specified vgap.
     *
     * @param vgap
     *            an int value indicating the vertical seperation of the
     *            components
     */
    public VerticalLayout(int vgap) {
        this(vgap, CENTER, TOP);
    }

    /**
     * Constructs a VerticalLayout instance anchored to the top with the
     * specified vgap and horizontal alignment.
     *
     * @param vgap
     *            an int value indicating the vertical seperation of the
     *            components
     * @param alignment
     *            an int value which is one of <code>RIGHT, LEFT,
     *                   CENTER, BOTH</code>
     *            for the horizontal alignment.
     */
    public VerticalLayout(int vgap, int alignment) {
        this(vgap, alignment, TOP);
    }

    /**
     * Constructs a VerticalLayout instance with the specified vgap, horizontal
     * alignment and anchoring
     *
     * @param vgap
     *            an int value indicating the vertical seperation of the
     *            components
     * @param alignment
     *            an int value which is one of <code>RIGHT, LEFT, CENTER,
     *                  BOTH</code>
     *            for the horizontal alignment.
     * @param anchor
     *            an int value which is one of <code>TOP, BOTTOM,
     *                  CENTER</code>
     *            indicating where the components are to appear if the display
     *            area exceeds the minimum necessary.
     */
    public VerticalLayout(int vgap, int alignment, int anchor) {
        this.vgap = vgap;
        this.alignment = alignment;
        this.anchor = anchor;
    }

    /**
     * Lays out the container.
     */
    public void layoutContainer(Container parent) {
        Insets insets = parent.getInsets();
        // NOTUSED Dimension dim = layoutSize(parent, false);
        synchronized (parent.getTreeLock()) {
            int n = parent.getComponentCount();
            Dimension pd = parent.getSize();
            int y = 0;
            // work out the total size
            for (int i = 0; i < n; i++) {
                Component c = parent.getComponent(i);
                Dimension d = c.getPreferredSize();
                y += d.height + vgap;
            }
            y -= vgap; // otherwise there's a vgap too many
            // Work out the anchor paint
            if (anchor == TOP) {
                y = insets.top;
            } else if (anchor == CENTER) {
                y = (pd.height - y) / 2;
            } else {
                y = pd.height - y - insets.bottom;
            }
            // do layout
            for (int i = 0; i < n; i++) {
                Component c = parent.getComponent(i);
                Dimension d = c.getPreferredSize();
                int x = insets.left;
                int wid = d.width;
                if (alignment == CENTER) {
                    x = (pd.width - d.width) / 2;
                } else if (alignment == RIGHT) {
                    x = pd.width - d.width - insets.right;
                } else if (alignment == BOTH) {
                    wid = pd.width - insets.left - insets.right;
                }
                c.setBounds(x, y, wid, d.height);
                y += d.height + vgap;
            }
        }
    }

    public Dimension minimumLayoutSize(Container parent) {
        return layoutSize(parent, true);
    }

    public Dimension preferredLayoutSize(Container parent) {
        return layoutSize(parent, false);
    }

    /**
     * Not used by this class.
     */
    public void addLayoutComponent(String name, Component comp) {
    }

    /**
     * Not used by this class.
     */
    public void removeLayoutComponent(Component comp) {
    }

    @Override
    public String toString() {
        return getClass().getName() + "[vgap=" + vgap + " align=" + alignment + " anchor=" + anchor + "]";
    }

    private Dimension layoutSize(Container parent, boolean minimum) {
        Dimension dim = new Dimension(0, 0);
        Dimension d;
        synchronized (parent.getTreeLock()) {
            int n = parent.getComponentCount();
            for (int i = 0; i < n; i++) {
                Component c = parent.getComponent(i);
                if (c.isVisible()) {
                    d = minimum ? c.getMinimumSize() : c.getPreferredSize();
                    dim.width = Math.max(dim.width, d.width);
                    dim.height += d.height;
                    if (i > 0) {
                        dim.height += vgap;
                    }
                }
            }
        }
        Insets insets = parent.getInsets();
        dim.width += insets.left + insets.right;
        dim.height += insets.top + insets.bottom + vgap + vgap;
        return dim;
    }
}