import java.io.*;
import java.net.URL;
import java.util.Base64;

public class ImageUtils {

    /**
     * 在線圖片 URL 轉(zhuǎn)為 Base64 字符串
     * @param imageUrl 圖片的在線地址
     * @return Base64 編碼字符串
     * @throws IOException 網(wǎng)絡(luò)異?；蜃x取失敗
     */
    public static String convertImageUrlToBase64(String imageUrl) throws IOException {
        URL url = new URL(imageUrl);
        try (InputStream is = url.openStream();
             ByteArrayOutputStream baos = new ByteArrayOutputStream()) {

            byte[] buffer = new byte[8192]; // 緩沖區(qū)
            int bytesRead;
            while ((bytesRead = is.read(buffer)) != -1) {
                baos.write(buffer, 0, bytesRead);
            }

            // 獲取字節(jié)數(shù)組并進(jìn)行 Base64 編碼
            byte[] imageBytes = baos.toByteArray();
            return Base64.getEncoder().encodeToString(imageBytes);
        }
    }

    // 示例入口
    public static void main(String[] args) throws IOException {
        String url = "https://example.com/image.jpg";
        String base64 = convertImageUrlToBase64(url);
        System.out.println("Base64 編碼結(jié)果：" + base64);
    }
}

import java.io.*;
import java.util.Base64;

public class Base64ToImage {

    /**
     * 將 Base64 編碼字符串轉(zhuǎn)為圖片并保存本地
     * @param base64Str 圖片的 Base64 字符串
     * @param outputPath 本地保存路徑，如 "output.jpg"
     * @throws IOException 寫入異常
     */
    public static void saveBase64ToImage(String base64Str, String outputPath) throws IOException {
        byte[] imageBytes = Base64.getDecoder().decode(base64Str);
        try (OutputStream os = new FileOutputStream(outputPath)) {
            os.write(imageBytes);
        }
    }

    // 示例入口
    public static void main(String[] args) throws IOException {
        String base64Str = "你的Base64編碼";
        saveBase64ToImage(base64Str, "output.jpg");
        System.out.println("圖片已保存至本地");
    }
}

import java.io.*;
import java.util.Base64;

public class Base64ToImage {

    /**
     * 從文本文件中讀取 Base64，并保存為圖片
     * @param base64FilePath 存儲(chǔ) Base64 的 .txt 文件路徑
     * @param outputImagePath 輸出圖片路徑
     * @throws IOException
     */
    public static void convertBase64FileToImage(String base64FilePath, String outputImagePath) throws IOException {
        // 讀取 Base64 內(nèi)容
        StringBuilder sb = new StringBuilder();
        try (BufferedReader reader = new BufferedReader(new FileReader(base64FilePath))) {
            String line;
            while ((line = reader.readLine()) != null) {
                sb.append(line);
            }
        }

        // 解碼并寫出圖片
        byte[] imageBytes = Base64.getDecoder().decode(sb.toString());
        try (OutputStream os = new FileOutputStream(outputImagePath)) {
            os.write(imageBytes);
        }
    }

    public static void main(String[] args) throws IOException {
        String base64File = "base64_image.txt";
        String outputPath = "restored.jpg";
        convertBase64FileToImage(base64File, outputPath);
        System.out.println("圖片還原成功！");
    }
}