在一个原有图片上叠加上指定的文字

编写一个工具类实现文字叠加的功能，叫ImageUttils

import cn.hutool.core.img.Img;
import cn.hutool.core.io.resource.Resource;import lombok.extern.slf4j.Slf4j;
import org.springframework.beans.factory.annotation.Value;
import org.springframework.stereotype.Component;
import org.springframework.util.StringUtils;
//import sun.misc.BASE64Encoder;
import org.apache.commons.codec.binary.Base64;import javax.imageio.ImageIO;
import java.awt.*;
import java.awt.image.BufferedImage;
import java.io.*;
import java.net.URL;/*** @ClassName ImageUtils* @Description 图片合成工具类* @Version**/
@Component
@Slf4j
public class ImageUtils {@Value("${image.fontSize}")private int fontSize;@Value("${image.backgroundColor}")private String backgroundColor;@Value("${image.fontColor}")private String fontColor;@Value("${image.compression}")private double compression;@Value("${text.line.height}")private int textLineHeight;@Value("${image.compress.size}")private Double imageCompressSize;public byte[] addTextToImage(String imageUrl, String text){
//        logger.info("修改base64");log.info("进入ImageUtils图片合成方法");long t1 = System.currentTimeMillis();//获取图片byte[] bytes = new byte[0];ByteArrayOutputStream baos  = null;try {Image image = ImageIO.read(new URL(imageUrl));int width = (int)(image.getWidth(null) * compression);int height = (int)(image.getHeight(null) * compression);log.debug("原图的大小为：width = {}, height = {}", width, height);int size = (int)(fontSize * compression);int n = width/size;String[] split = null;bytes = null;try {text= getStringByEnter(n, text);
//                split = StringUtils.split(text, "\\r?\\n");//更换成一下方式，上面的方法获取的split = nullsplit = text.split("\n");} catch (Exception e) {log.error("imageUrl={},text={},getStringByEnter error , e = {}", imageUrl, text, e);}int heightPlus = 0;if (split== null || split.length==0){heightPlus = textLineHeight;} else {heightPlus = split.length * textLineHeight;}log.debug("heightPlus = {}", heightPlus);BufferedImage bi = new BufferedImage(width,height,BufferedImage.TYPE_INT_RGB);Graphics2D g2 =  bi.createGraphics();g2.drawImage(image, 0, 0, width, height - heightPlus, null);g2.setColor(colorMapping(fontColor));g2.setFont(new Font("宋体",Font.BOLD, size));//g2.drawString(text, 0, height - 2 * size);for(int i = 0 ; i < split.length; i++){String line = split[i];g2.drawString(line, 0, height - size*(split.length - i));}g2.dispose();baos = new ByteArrayOutputStream();//图片格式要保证和源图格式相同，否则图片大小差别会很大ImageIO.write(bi, "jpg", baos);bytes = baos.toByteArray();//压缩图片ByteArrayOutputStream out = new ByteArrayOutputStream();InputStream sbs = new ByteArrayInputStream(bytes);Img.from(sbs).setQuality(imageCompressSize).write(out);return out.toByteArray();} catch (Exception e) {log.error("imageUrl={}, text={}, addTextToImage error = {}",imageUrl, text, e);} finally {try {baos.close();} catch (IOException e) {log.error("imageUrl={}, text={}, io close error , e = {}", imageUrl,text, e);}}long t2 = System.currentTimeMillis();log.info("imageUrl={}, text={}, addTextToImage cost = {}ms", imageUrl,text, t2 -t1);return bytes;}private static String getClassPath() {String classPath = null;URL url = ImageUtils.class.getResource("/");if(null != url){classPath = url.toString().replaceFirst("file:/", "/");}return classPath;}/*** 自动换行* @param string* @return*/public String getStringByEnter(int length, String string) throws Exception {StringBuilder sb = new StringBuilder();for (int i = 0; i < string.length(); i++){/*if (string.substring(0, i).getBytes("GBK").length > length){return string.substring(0, i - 1) + "\n" +getStringByEnter(length, string.substring(i - 1));}*/sb.append(string.charAt(i));if((i+1)%length == 0){sb.append("\n");}}return sb.toString();}public String encodeBase64File(String path) throws Exception {File file = new File(path);FileInputStream inputFile = new FileInputStream(file);byte[] buffer = new byte[(int) file.length()];inputFile.read(buffer);inputFile.close();
//        return new BASE64Encoder().encode(buffer);return Base64.encodeBase64String(buffer);}private Color colorMapping(String color){Color color1 = Color.BLACK;switch (color) {case "red":color1 =  Color.RED;break;case "white":color1 = Color.WHITE;break;case "gray":color1 = Color.GRAY;break;case "blue":color1 = Color.BLUE;break;default:color1 = Color.BLACK;break;}return color1;}
}

其中入参在配置文件中，如下

#------图片页面字体设置-------
image.backgroundColor=black
image.fontColor=red
image.fontSize=20
image.compression=1.0
text.line.height=33