java 根据指定链接生成二维码

import com.google.zxing.BarcodeFormat;
import com.google.zxing.EncodeHintType;
import com.google.zxing.MultiFormatWriter;
import com.google.zxing.common.BitMatrix;

import javax.imageio.ImageIO;
import javax.swing.filechooser.FileSystemView;
import java.awt.image.BufferedImage;
import java.io.File;
import java.io.IOException;
import java.io.OutputStream;
import java.util.HashMap;
import java.util.Map;

public class QrCodeUtil {
    public static void main(String[] args) {
        String url = "http://www.baidu.com";
        String path = FileSystemView.getFileSystemView().getHomeDirectory() + File.separator + "testQrcode";
        String fileName = "temp.jpg";
        createQrCode(url, path, fileName);
    }

    public static String createQrCode(String url, String path, String fileName) {
        try {
            Map<EncodeHintType, String> hints = new HashMap<>();
            hints.put(EncodeHintType.CHARACTER_SET, "UTF-8");
            B