优化getCaptcha接口

ibms-data-sdk/src/main/java/com/persagy/ibms/data/sdk/util/HttpClientUtil.java

@@ -193,8 +193,15 @@ public class HttpClientUtil {
 		entity.setContentType("application/json");
 		HttpResponse httpResponse = client.execute(httpost);
 		String guid = httpResponse.getHeaders("guid")[0].getValue();
-		HttpEntity entity2 = httpResponse.getEntity();
-		byte[] data = EntityUtils.toByteArray(entity2);
+		InputStream is = httpResponse.getEntity().getContent();
+		ByteArrayOutputStream baos = new ByteArrayOutputStream();
+		int b = -1;
+		while ((b = is.read()) != -1) {
+			baos.write(b);
+		}
+		baos.close();
+		is.close();
+		byte[] data = baos.toByteArray();
 		BASE64Encoder encoder = new BASE64Encoder();
 		String imageBase64 = "data:image/png;base64," + encoder.encodeBuffer(data).trim();
 		imageBase64 = imageBase64.replaceAll("\n", "").replaceAll("\r", "").replaceAll(" ", "");