java模仿微信QQ群聊头像拼接，根据群聊内的用户头像拼接群聊头像，九宫格
效果图，这里只放了几张，1-9张图片都可以的，如果图片路径是从数据库查出来的相对路径，记得加上绝对路径否则会报找不到读取文件错误，把查出来的群成员头像路径加上绝对路径前缀，封装到list集合即可，然后在调用下面的工具类
List paths = new ArrayList<>();
String logoUrl = UUID.randomUUID() + “.png”;//防止覆盖
UpdateGroupLogoUtil.generate(paths, BIDE.getFilePath() + logoUrl);
BIDE.getFilePath() + logoUrl这个参数是拼接之后生成的图片地址和图片名
如：F:\zsl\33 .jpg
附带测试
package im.bide.utils;import javax.imageio.ImageIO;import java.awt.*;import java.awt.geom.AffineTransform;import java.awt.image.AffineTransformOp;import java.awt.image.BufferedImage;import java.io.File;import java.io.IOException;import java.util.ArrayList;import java.util.List;public abstract class UpdateGroupLogoUtil {/*** 图片格式：JPG*/private static final String PICTRUE_FORMATE = "jpg";/*** 生成组合头像* 画布宽度和高度为166，图片间距为2** @param paths 用户头像路径列表* @param outPath 生成后的头像保存路径* @throws IOException*/public static void generate(List<String> paths, String outPath) throws IOException {generate(paths, 166, 4, outPath);}/*** 生成组合头像** @param paths 用户头像路径列表* @param length 画板的宽高和高度* @param interval 画板中的图片间距* @param outPath 生成后的头像保存路径* @throws IOException*/public static void generate(List<String> paths, int length, int interval, String outPath) throws IOException {int wh = (length - interval * 4) / 3; // 每个图片的宽高和高度：图片数>4if (paths.size() == 1) {wh = length - interval * 2; // 每个图片的宽高和高度：图片数=1}if (paths.size() > 1 && paths.size() < 5) {wh = (length - interval * 3) / 2; // 每个图片的宽高和高度：图片数>0并且<5}List<BufferedImage> bufferedImages = new ArrayList<BufferedImage>();for (int i = 0; i < paths.size(); i++) {bufferedImages.add(UpdateGroupLogoUtil.resize(paths.get(i), wh, wh, false));}// BufferedImage.TYPE_INT_RGB可以自己定义可查看APIBufferedImage outImage = new BufferedImage(length, length, BufferedImage.TYPE_INT_RGB);// 生成画布Graphics g = outImage.getGraphics();Graphics2D g2d = (Graphics2D) g;// 设置背景色g2d.setBackground(new Color(255, 255, 255));// 通过使用当前绘图表面的背景色进行填充来清除指定的矩形。g2d.clearRect(0, 0, length, length);// 开始拼凑 根据图片的数量判断该生成那种样式的组合头像for (int i = 1; i <= bufferedImages.size(); i++) {int j = i % 3 + 1;if (bufferedImages.size() < 5) {j = i % 2 + 1;}int x = interval * j + wh * (j - 1);int split = (wh + interval) / 2;if (bufferedImages.size() == 9) {if (i <= 3) {g2d.drawImage(bufferedImages.get(i - 1), x, wh * 2 + interval * 3, null);} else if (i <= 6) {g2d.drawImage(bufferedImages.get(i - 1), x, wh + interval * 2, null);} else {g2d.drawImage(bufferedImages.get(i - 1), x, interval, null);}} else if (bufferedImages.size() == 8) {if (i <= 3) {g2d.drawImage(bufferedImages.get(i - 1), x, wh * 2 + interval * 3, null);} else if (i <= 6) {g2d.drawImage(bufferedImages.get(i - 1), x, wh + interval * 2, null);} else {g2d.drawImage(bufferedImages.get(i - 1), x - split, interval, null);}} else if (bufferedImages.size() == 7) {if (i <= 3) {g2d.drawImage(bufferedImages.get(i - 1), x, wh * 2 + interval * 3, null);} else if (i <= 6) {g2d.drawImage(bufferedImages.get(i - 1), x, wh + interval * 2, null);} else {g2d.drawImage(bufferedImages.get(i - 1), (length - wh) / 2, interval, null);}} else if (bufferedImages.size() == 6) {if (i <= 3) {g2d.drawImage(bufferedImages.get(i - 1), x, wh * 2 + interval * 3 - split, null);} else if (i <= 6) {g2d.drawImage(bufferedImages.get(i - 1), x, wh + interval * 2 - split, null);}} else if (bufferedImages.size() == 5) {if (i <= 3) {g2d.drawImage(bufferedImages.get(i - 1), x, wh * 2 + interval * 3 - split, null);} else {g2d.drawImage(bufferedImages.get(i - 1), x - split, wh + interval * 2 - split, null);}} else if (bufferedImages.size() == 4) {if (i <= 2) {g2d.drawImage(bufferedImages.get(i - 1), x, wh + interval * 2, null);} else {g2d.drawImage(bufferedImages.get(i - 1), x, interval, null);}} else if (bufferedImages.size() == 3) {if (i <= 2) {g2d.drawImage(bufferedImages.get(i - 1), x, wh + interval * 2, null);} else {g2d.drawImage(bufferedImages.get(i - 1), x - split, interval, null);}} else if (bufferedImages.size() == 2) {g2d.drawImage(bufferedImages.get(i - 1), x, wh + interval * 2 - split, null);} else if (bufferedImages.size() == 1) {g2d.drawImage(bufferedImages.get(i - 1), interval, interval, null);}// 需要改变颜色的话在这里绘上颜色。可能会用到AlphaComposite类}ImageIO.write(outImage, PICTRUE_FORMATE, new File(outPath));}public static BufferedImage resize(String filePath, int width, int height) {try {BufferedImage bi = ImageIO.read(new File(filePath));bi.getSubimage(0, 0, width, height);} catch (IOException e) {e.printStackTrace();}return null;}/*** 图片缩放** @param filePath 图片路径* @param height 高度* @param width 宽度* @param bb 比例不对时是否需要补白*/public static BufferedImage resize(String filePath, int height, int width, boolean bb) {try {double ratio = 0; // 缩放比例File f = new File(filePath);BufferedImage bi = ImageIO.read(f);Image itemp = bi.getScaledInstance(width, height, Image.SCALE_SMOOTH);// 计算比例if ((bi.getHeight() > height) || (bi.getWidth() > width)) {if (bi.getHeight() > bi.getWidth()) {ratio = (new Integer(height)).doubleValue() / bi.getHeight();} else {ratio = (new Integer(width)).doubleValue() / bi.getWidth();}AffineTransformOp op = new AffineTransformOp(AffineTransform.getScaleInstance(ratio, ratio), null);itemp = op.filter(bi, null);}if (bb) {BufferedImage image = new BufferedImage(width, height, BufferedImage.TYPE_INT_RGB);Graphics2D g = image.createGraphics();g.setColor(Color.white);g.fillRect(0, 0, width, height);if (width == itemp.getWidth(null)) {g.drawImage(itemp, 0, (height - itemp.getHeight(null)) / 2, itemp.getWidth(null), itemp.getHeight(null), Color.white, null);} else {g.drawImage(itemp, (width - itemp.getWidth(null)) / 2, 0, itemp.getWidth(null), itemp.getHeight(null), Color.white, null);}g.dispose();itemp = image;}return (BufferedImage) itemp;} catch (IOException e) {e.printStackTrace();}return null;}public static void main(String[] args) throws Exception {ArrayList<String> picUrls = new ArrayList<>();String pic = "F:\\zsl\\";picUrls.add(pic + "1.jpg");picUrls.add(pic + "2.jpg");picUrls.add(pic + "3.jpg");// picUrls.add(pic + "4.jpg");// picUrls.add(pic + "5.jpg");// picUrls.add(pic + "6.jpg");// picUrls.add(pic + "7.jpg");// picUrls.add(pic + "8.jpg");// picUrls.add(pic + "9.jpg");//2 调用工具类 生成九宫格 并保存在已有路径UpdateGroupLogoUtil.generate(picUrls, "F:\\zsl\\33 .jpg");}}
