java之base64解码

import org.eclipse.paho.client.mqttv3.IMqttDeliveryToken;
import org.eclipse.paho.client.mqttv3.MqttCallback;
import org.eclipse.paho.client.mqttv3.MqttClient;
import org.eclipse.paho.client.mqttv3.MqttConnectOptions;
import org.eclipse.paho.client.mqttv3.MqttException;
import org.eclipse.paho.client.mqttv3.MqttMessage;
import org.eclipse.paho.client.mqttv3.MqttSecurityException;
import org.eclipse.paho.client.mqttv3.persist.MemoryPersistence;
import org.jsoup.Jsoup;
import org.jsoup.nodes.Document;
import org.jsoup.nodes.Element;
import org.jsoup.select.Elements;
import okhttp3.*;
import java.io.IOException;
import java.nio.file.Files;
import java.nio.file.Paths;
import java.util.Base64;
public class main {


    public static void main(String[] args) {


        String base64Data = "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"; // 示例Base64编码字符串（"Hello World!"）
        String outputPath = "test.png"; // 输出文件路径

        try {
            // 1. Base64解码
            byte[] decodedBytes = Base64.getDecoder().decode(base64Data);

            // 2. 保存到文件
            Files.write(Paths.get(outputPath), decodedBytes);
            System.out.println("文件保存成功: " + outputPath);
        } catch (IOException e) {
            System.err.println("处理失败: " + e.getMessage());
            e.printStackTrace();
        }
    }
}