Java基礎 awt Graphics2D 生成矩形圖片並向其中畫一條直線

時間 2019-11-06

標籤 java 基礎 awt graphics2d graphics 生成矩形圖片並向其中一條直線欄目 Java 简体版

原文原文鏈接

JDK ：OpenJDK-11

OS ：CentOS 7.6.1810

IDE ：Eclipse 2019‑03

typesetting ：Markdown

code

package per.jizuiku.gui;

import java.awt.BasicStroke;
import java.awt.Color;
import java.awt.Graphics2D;
import java.awt.image.BufferedImage;
import java.io.FileNotFoundException;
import java.io.FileOutputStream;
import java.io.IOException;

import javax.imageio.ImageIO;

/**
 * @author 給最苦
 * @date 2019/06/30
 * @blog www.cnblogs.com/jizuiku
 */
public class Demo {

    /**
     * @param args
     */
    public static void main(String[] args) {
        try {
            getImage();
        } catch (IOException e) {
            // TODO Auto-generated catch block
            e.printStackTrace();
        }

    }

    /**
     * 
     * @throws FileNotFoundException
     * @throws IOException
     */
    public static void getImage() throws FileNotFoundException, IOException {
        // 獲得圖片緩衝區
        int width = 100;
        int height = 50;
        int imageType = BufferedImage.TYPE_INT_BGR;
        BufferedImage myImage = new BufferedImage(width, height, imageType);

        // 獲得畫筆
        Graphics2D pen = (Graphics2D)myImage.getGraphics();

        // 設置筆的顏色,即背景色
        pen.setColor(Color.WHITE);

        // 畫出一個矩形
        // 座標x 座標y 寬度100 長度50
        pen.fillRect(0, 0, 100, 50);

        // 字的顏色 和 背景的顏色 要不一樣的
        pen.setColor(Color.blue);

        // 劃線
        // 點動成線，線動成面，面動成體
        // 兩點肯定一條直線
        int xStart = 5;
        int yStart = 15;
        int xEnd = 60;
        int yEnd = 30;

        // 設置線的寬度
        float lineWidth = 7F;
        pen.setStroke(new BasicStroke(lineWidth));

        pen.drawLine(xStart, yStart, xEnd, yEnd);

        ImageIO.write(myImage, "JPEG", new FileOutputStream("line" + ".jpg"));

    }

}

result

sourceCode

/**
    * Draws a line, using the current color, between the points
    * <code>(x1,&nbsp;y1)</code> and <code>(x2,&nbsp;y2)</code>
    * in this graphics context's coordinate system.
    * @param   x1  the first point's <i>x</i> coordinate.
    * @param   y1  the first point's <i>y</i> coordinate.
    * @param   x2  the second point's <i>x</i> coordinate.
    * @param   y2  the second point's <i>y</i> coordinate.
    */
public abstract void drawLine(int x1, int y1, int x2, int y2);