微信小程序 - 通过调用小程序接口在本地生成小程序码的图片

import java.io.DataOutputStream;
import java.io.File;
import java.net.HttpURLConnection;
import java.net.URL;
import java.util.HashMap;
import java.util.Map;
import javax.imageio.stream.FileImageOutputStream;
import org.apache.commons.io.IOUtils;
import com.alibaba.fastjson.JSON;
import com.pucheit.common.util.Utils;

public class Generator {
	
	public static final String FileBasePath = "D:/微信小程序二维码/";
	public static final String AppId = "xxxx";//核工院点餐正式
	public static final String AppSecret = "xxxxxx";

	public static String getAccessToken(){
		String url = "https://api.weixin.qq.com/cgi-bin/token?grant_type=client_credential&appid="+AppId+"&secret="+AppSecret;
		String result = Utils.httpGet(url,new HashMap());
		Map reMap = JSON.parseObject(result,Map.class);
		String accessToken = reMap.get("access_token");
		return accessToken;
	}
	
	public static void getQRCode(String accessToken) {
            try {
                String url = "https://api.weixin.qq.com/wxa/getwxacode?access_token="+accessToken;
                Map param = new HashMap<>();
                param.put("path", "pages/index/index");
                param.put("width", 430);
            
                URL urlObj = new URL(url);
                HttpURLConnection connection = (HttpURLConnection) urlObj.openConnection();
                connection.setDoOutput(true);
                connection.setDoInput(true);
                connection.setRequestMethod("POST");
                connection.setUseCaches(false);
                connection.setInstanceFollowRedirects(true);
                connection.setRequestProperty("Content-type", "application/json;charset=UTF-8"); 
                connection.connect();

                //POST请求
                DataOutputStream out = new DataOutputStream(connection.getOutputStream());
                out.writeBytes(JSON.toJSONString(param));
                out.flush();
                out.close();

                //读取响应
                byte[] oriBytes = IOUtils.toByteArray(connection.getInputStream());
                FileImageOutputStream imageOutput = new FileImageOutputStream(new File(FileBasePath+"aa.png"));//打开输入流
                imageOutput.write(oriBytes, 0, oriBytes.length);//将byte写入硬盘
                imageOutput.close();
            
            } catch (Exception e) {
        	e.printStackTrace();
            }
        }
}