话不多说，直接上成品

原底图

开始：入口：get()

 package com.ruoyi.web.controller.picture;

import com.ruoyi.common.core.domain.R;
import com.ruoyi.common.utils.ImagEyeCopyHelper;
import com.ruoyi.common.utils.ImageUtils;
import com.ruoyi.system.service.IPictureService;
import io.swagger.annotations.Api;
import io.swagger.annotations.ApiOperation;
import org.springframework.beans.factory. annotation .Autowired;
import org.springframework.web.bind.annotation.PostMapping;
import org.springframework.web.bind.annotation. Request Mapping;
import org.springframework.web.bind.annotation.RestController;

import  javax .imageio.ImageIO;
import java.awt.*;
import java.awt.image.BufferedImage;
import java.io.BufferedOutputStream;
import java.io. File ;
import java.io.FileOutputStream;

@Api(description = "图片生成控制器")
@RestController
@RequestMapping("/picture")
public class PictureController {

    @Autowired
     private  IPictureService iPictureService;


    @ApiOperation("生成图片")
    @PostMapping("/generate")
    public R generate()  throws  Exception {
        return R.ok(iPictureService.generate());
    }

    public  static   void  main(String[] args) throws Exception {
        System.out.println(get());
    }


    public static String get() throws Exception {
        String imageUrl = "";
        final BufferedImage thumbImage = ImagEyeCopyHelper.getBaseImage(imageUrl);
        // 先添加平铺式水印
        ImageUtils.addWaterMark(thumbImage, "@是我小汤圆呀");
        // 添加文字内容填充
        Font font = new Font("微软雅黑", Font.PLAIN, 45);
        Color red = new Color(255, 200, 0,255);
        Color black = new Color(0, 0, 0, 255);
        ImageUtils.addWaterMark(thumbImage, "大风吹倒梧桐树，自有旁人论短长。", red, font, 180, 320);
        ImageUtils.addWaterMark(thumbImage, "针对同一件事，不同的人站在不同的角度，", black, font, 180, 510);
        ImageUtils.addWaterMark(thumbImage, "会有不同的看法。任何事情都有评论，不要", black , font, 180, 610);
        ImageUtils.addWaterMark(thumbImage, "太计较别人的看法，太计较别人的看法不是", black, font, 180, 710);
        ImageUtils.addWaterMark(thumbImage, "一件好事，会迷失自我。", black, font, 180, 810);
        ImageUtils.addWaterMark(thumbImage, "2022年10月26日", black, font, 700, 910);
        ImageUtils.addWaterMark(thumbImage, "@是我小汤圆呀", black, font, 710, 1010);
        // 写到本地
         String  path = "D:\\" + System.currentTimeMillis() + ".jpg";
        BufferedOutputStream out = new BufferedOutputStream(new FileOutputStream(path));
        String formatName = path.substring(path.lastIndexOf(".") + 1);
        System.out.println("formatName is :" + formatName);
        ImageIO.write(thumbImage, formatName, new File(path));
        out.close();
        return null;
    }


}
  

ImagEyeCopyHelper.java

 package com.ruoyi.common.utils;

import javax.imageio.ImageIO;
import java.awt.*;
import java.awt.image.BufferedImage;
import java.io.IOException;
import java.io. InputStream ;

public class ImagEyeCopyHelper {

    /**
     * left代表图片距离画布最左端的距离
     */
    private static final int left = 1320;
    /**
     * top代表图片距离画布最上端的距离
     */
    private static final int top = 80;

    /**
     * 获取一张基础的图片素材底图
     *
     * @param userImagUrl 网络图片地址
     * @return
     * @throws IOException
     */
    public static BufferedImage getBaseImage(String userImagUrl) throws IOException {
        // 加载本地基础底图图片
        InputStream inputStream = ImagEyeCopyHelper.class.getClassLoader().getResourceAsStream("picture/bg-clean-01.jpg");
        BufferedImage thumbImage = ImageIO.read(inputStream);
        Graphics2D g = thumbImage.createGraphics();

        if (StringUtils.isEmpty(userImagUrl)) {
            return thumbImage;
        }

        BufferedImage minImag = ImageUtils.getUrlByBufferedImage(userImagUrl);
        // 先裁切成圆形
        minImag = ImageUtils.convertCircular(minImag);
        // 图片合成
        g.drawImage(minImag.getScaledInstance(160, 160, Image.SCALE_SMOOTH), left, top, null);
        return thumbImage;
    }


}
  

ImageUtils.java

 package com.ruoyi.common.utils;

import javax.imageio.ImageIO;
import java.awt.*;
import java.awt.font. Font RenderContext;
import java.awt.font.TextLayout;
import java.awt.geom.AffineTransform;
import java.awt.geom.Ellipse2D;
import java.awt.image.BufferedImage;
import java.io.IOException;
import java.net.HttpURLConnection;
import java.net.URL;

public class ImageUtils {

    /**
     * 通过网络获取图片
     *
     * @param url
     * @return
     */
    public static BufferedImage getUrlByBufferedImage(String url) {
        try {
            URL urlObj = new URL(url);
            HttpURLConnection conn = (HttpURLConnection) urlObj.openConnection();
            // 连接超时
            conn.setDoInput(true);
            conn.setDoOutput(true);
            conn.setConnectTimeout(25000);
            // 读取超时 --服务器响应比较慢,增大时间
            conn.setReadTimeout(25000);
            conn.setRequestMethod("GET");
            conn.addRequestProperty("Accept-Language", "zh-cn");
            conn.addRequestProperty("Content-type", "image/jpeg");
            conn.addRequestProperty("User-Agent", "Mozilla/4.0 (compatible; MSIE 8.0; Windows NT 5.1; Trident/4.0; .NET CLR 2.0.50727)");
            conn.connect();
            BufferedImage bufImg = ImageIO.read(conn.getInputStream());
            conn.disconnect();
            return bufImg;
        } catch (Exception e) {
            e.printStackTrace();
        }
        return null;
    }

    /**
     * 传入的图像必须是正方形的 才会 圆形 如果是长方形的比例则会变成椭圆的
     *
     * @param image 用户头像
     * @return
     * @throws IOException
     */
    public static BufferedImage convertCircular(BufferedImage image) throws IOException {
        int min;//若是长方形图片则按照边短的去裁剪成圆，如果没有这个就会变成椭圆
        if (image.getWidth() > image.getHeight()) {
            min = image.getHeight();
        } else {
            min = image.getWidth();
        }

        // 透明底的图片
        BufferedImage bi2 = new BufferedImage(min, min, BufferedImage.TYPE_4BYTE_ABGR);
        Ellipse2D.Double shape = new Ellipse2D.Double(0, 0, min, min);
        Graphics2D g2 = bi2.createGraphics();
        g2.setClip(shape);
        // 使用 setRenderingHint 设置抗锯齿
        g2.setRenderingHint(RenderingHints.KEY_ANTIALIASING, RenderingHints.VALUE_ANTIALIAS_ON);
        g2.drawImage(image, 0, 0, null);
        // 设置颜色
        g2.setBackground(Color.green);
        g2.dispose();
        return bi2;
    }

    /**
     * 对图片上添加平铺式水印
     *
     * @param image
     * @param text
     * @throws IOException
     */
    public static void addWaterMark(BufferedImage image, String text) {
        if (StringUtils.isEmpty(text)) {
            return;
        }
        int angel = -30;//旋转角度
        int xpadding = 400;//每个水印水平间隔
        int ypadding = 400;//每个水印垂直间隔
        int fontSize = 22;

        Graphics2D g = image.createGraphics();
        g.setRenderingHint(RenderingHints.KEY_ANTIALIASING, RenderingHints.VALUE_ANTIALIAS_ON);

        //绘制原图片
        float alpha = 1F;
        AlphaComposite ac = AlphaComposite. getInstance (AlphaComposite.SRC_OVER, alpha);
        g.setComposite(ac);
        g.drawImage(image, 0, 0, image.getWidth(), image.getHeight(), null);
        g.setBackground(Color.BLACK);

        //开始绘制水印
        //水印字体
        Font font = new Font("微软雅黑", Font.BOLD, fontSize);
        g.setFont(font);
        FontRenderContext frc = g.getFontRenderContext();
        TextLayout tl = new TextLayout(text, font, frc);
        //水印串宽度
        int stringWidth = g.getFontMetrics(g.getFont()).charsWidth(text.toCharArray(), 0, text.length());

        //旋转水印
        g.rotate(Math.toRadians(angel), (double) image.getWidth() / 2, (double) image.getHeight() / 2);
        //水印透明度
        g.setComposite(AlphaComposite.getInstance(AlphaComposite.SRC_OVER, 0.1F));
        // 字体色
        g.setColor(Color.black);

        int x = -image.getHeight() / 2;
        int y = -image.getWidth() / 2;

        //循环绘制
        while (x < image.getWidth() + image.getHeight() / 2) {
            y = -image.getWidth() / 2;
            while (y < image.getHeight() + image.getWidth() / 2) {
                Shape sha = tl.getOutline(AffineTransform.getTranslateInstance(x, y));
                g.fill(sha);

                y += ypadding;
            }
            x += stringWidth + xpadding;
        }
        //释放资源
        g.dispose();
    }

    /**
     * 对图片上添加文字 普通文字
     *
     * @param bufImg           源图片
     * @param waterMarkContent 文字内容
     * @param markContentColor 文字颜色
     * @param font             文字字体
     * @param x                坐标 左上角为起点
     * @param y                坐标 左上角为起点
     */
    public static void addWaterMark(BufferedImage bufImg, String waterMarkContent, Color markContentColor, Font font, int x, int y) {
        try {
            // 加水印
            Graphics2D g = bufImg.createGraphics();
            g.drawImage(bufImg, 0, 0, bufImg.getWidth(), bufImg.getHeight(), null);
            g.setColor(markContentColor); //根据图片的背景设置水印颜色

            g.setFont(font);              //设置字体
            //设置水印的坐标
            g.drawString(waterMarkContent, x, y);  //画出水印
            g.dispose();
        } catch (Exception e) {
            e.printStackTrace();
        }
    }
}
  

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