Java合并PNG图像（保持背景透明）
import java.awt.Graphics2D;import java.awt.Transparency;import java.awt.image.BufferedImage;import java.io.File;import java.io.IOException;import java.util.List;import javax.imageio.ImageIO;public class PngFileWriter { public void append(List<String> inputFileNameList, String outputFileName, boolean isX) { if (inputFileNameList == null || inputFileNameList.size() == 0) { return; } try { boolean isFirstPng = true; BufferedImage outputImg = null; int outputImgW = 0; int outputImgH = 0; for (String pngFileName : inputFileNameList) { if (isFirstPng) { isFirstPng = false; outputImg = ImageIO.read(new File(pngFileName)); outputImgW = outputImg.getWidth(); outputImgH = outputImg.getHeight(); } else { BufferedImage appendImg = ImageIO.read(new File(pngFileName)); int appendImgW = appendImg.getWidth(); int appendImgH = appendImg.getHeight(); if (isX) { outputImgW = outputImgW + appendImgW; outputImgH = outputImgH > appendImgH ? outputImgH : appendImgH; } else { outputImgW = outputImgW > appendImgW ? outputImgW : appendImgW; outputImgH = outputImgH + appendImgH; } // create basic image Graphics2D g2d = outputImg.createGraphics(); BufferedImage imageNew = g2d.getDeviceConfiguration().createCompatibleImage(outputImgW, outputImgH, Transparency.TRANSLUCENT); g2d.dispose(); g2d = imageNew.createGraphics(); int oldImgW = outputImg.getWidth(); int oldImgH = outputImg.getHeight(); g2d.drawImage(outputImg, 0, 0, oldImgW, oldImgH, null); if (isX) { g2d.drawImage(appendImg, oldImgW, 0, appendImgW, appendImgH, null); } else { g2d.drawImage(appendImg, 0, oldImgH, appendImgW, appendImgH, null); } g2d.dispose(); outputImg = imageNew; } } writeImageLocal(outputFileName, outputImg); } catch (Exception e) { e.printStackTrace(); } } private void writeImageLocal(String fileName, BufferedImage image) { if (fileName != null && image != null) { try { File file = new File(fileName); ImageIO.write(image, "png", file); } catch (IOException e) { e.printStackTrace(); } } }}?