Key Takeaways
- Java bulk send on an Android SMS gateway is HttpClient to POST /messages (or POST /campaigns) — not a Maven “Complete SMS SDK.”
- Several numbers in to[], or a saved list via campaigns. Confirm live JSON in Developer Center.
- Tight for-loops outrun the SIM. Queue, cap msgs/min, persist ids, same Idempotency-Key on retry.
- HTTP 200 is accepted. Watch DLR mid-campaign. Unknown ≠ resend the whole file.
- You bring the phone and operator credit. Platform pricing is devices plus send volume.
A loop is not a radio
Hub: Android SMS gateway API. Feature: bulk CSV. This page is a Java worker that will not melt a SIM. Live fields: Developer Center.
We meter devices and volume. A faster executor does not include pulsa. Checklist: bulk campaign checklist.
HTTPS/JSON, not a Java SDK
POST https://app.sms-gateway.app/api/v1/messages with Authorization: Bearer. HttpClient intro: OpenJDK HttpClient. PHP/C# on this site are REST samples too — not packages: PHP.
“If your thread pool is sized for the JVM, not the tray, you will discover OEM rate ceilings as a production incident.”
Bulk-loop failure modes
| Symptom | Likely cause | First check |
|---|---|---|
| Pending pile | Loop faster than claim | Last-seen; cap concurrency |
| Duplicate rows | Retry without Idempotency-Key | Stable key per recipient+campaign |
| OTP delayed | Same deviceId | Named campaign pool |
| Excel wrecked MSISDNs | Scientific notation | Contacts |
| Mapped 200 to delivered | No DLR | DLR |
Pace to devices
Multi-device multiplies radios, not magic. Multi-device. SMS Retriever is end-user OTP UX — not this loop. Pairing.
Keep OTP off this loop
Isolate OTP. STOP: auto-reply. Pricing.
Next steps
Canary 10 rows. Watch Pending age. Then the list. Operator credit stays yours.
Related product pages
Jump to the live product docs for this topic—not another long-form article.
- bulk SMS from Excel and CSVSpreadsheet campaigns
- bulk SMS with consent best practicesHigh-volume outreach
- SMS API documentationLive endpoint reference
- device and SMS volume pricingPlans and allowances
