> For clean Markdown of any page, append .md to the page URL. > For a complete documentation index, see https://docs.6mm.com/llms.txt. > For AI client integration (Claude Code, Cursor, etc.), connect to the MCP server at https://docs.6mm.com/_mcp/server. # Contract Ledger This guide targets **Agent Java SDK `v0.3.0`**, Java 8+, and the tagged public contract. Examples run in a partner backend after initializing `client` in [Quick Start](/sdk/agent-sdk/java/quick-start). ## Example prerequisites The Java snippets share these imports. Initialize `client` using Quick Start and obtain `platformUserId` from the saved binding. Example user/order IDs must be replaced with your own persisted values. ```java import com.sixmm.agent.*; import com.sixmm.agent.model.*; import java.util.*; ``` ## `listPerpetualLedger` Request model: `PerpetualLedgerRequest`. ```java import com.sixmm.agent.model.PerpetualLedgerRequest; import com.sixmm.agent.model.PerpetualResponse; import java.util.Collections; PerpetualLedgerRequest request = new PerpetualLedgerRequest(); request.platformUserIds = Collections.singletonList("1188041528"); request.limit = 100; request.endTime = System.currentTimeMillis(); request.startTime = request.endTime - 3_600_000L; PerpetualResponse response = client.listPerpetualLedger(request); System.out.println(response.data.items.size()); System.out.println(response.data.hasMore); System.out.println(response.data.nextCursor); ``` ### Request fields | Field | Java type | Required | Meaning | | ----------------- | ------------------------ | ----------- | -------------------------------------------------------------------------------------------------------------------------------------- | | `platformUserIds` | `java.util.List` | Conditional | 1–100 unique public IDs; required for fills and conditional orders. Omit on supported queries for direct-player scope; \[] is invalid. | | `assetType` | `String` | No | Asset classification as returned by the ledger; do not assume USDT. | | `changeType` | `String` | No | Ledger business-change type, preserving source values. | | `startTime` | `Long` | No | Inclusive Unix milliseconds; use a fixed UTC history window. | | `endTime` | `Long` | No | Exclusive Unix milliseconds. | | `limit` | `Integer` | No | Default 500; 1–1000. | | `cursor` | `String` | No | Use the returned nextCursor with unchanged filters; stop when hasMore is false. | The example reads one page. For required fields, player scope, filter semantics, limit, cursor and bounded retries, follow [Query overview](/sdk/agent-sdk/java/perpetual-queries). Keep all filters unchanged while paging; do not interpret an error as an empty result. ## Contract ledger records Interface: `account/ledger`. The returned data only contains the following 11 business fields and does not carry the order boolean flags. | `data` field | type | meaning | | --------------------- | ------- | ------------------------------------------------------------------------------------------------------------------------------------------------------------------------------ | | `ledgerId` | string | The source ledger records to the transaction ID; the same transaction may be split into multiple details | | `symbol` | string | Related trading pair, may be omitted if not related | | `assetType` | string | Asset type, saved by source value; used for asset classification, not inferred by default USDT | | `changeType` | string | Account change business type, saved according to source value, such as handling fee, profit and loss, transfer; can be filtered by the same field | | `amount` | string | The change amount of this detail, a positive number indicates an increase, a negative number indicates a decrease; precision is retained | | `walletBalanceBefore` | string | The wallet balance before the account change recorded in this detail | | `walletBalanceAfter` | string | The wallet balance after the account change recorded in this detail | | `frozenBalanceBefore` | string | The frozen balance recorded before the account change is recorded in this detail | | `frozenBalanceAfter` | string | The frozen balance recorded in this detail after the account change | | `referenceId` | string | Associated business number; interpreted as changeType and cannot be uniformly regarded as order orderId; "0" indicates that the source does not have a valid associated number | | `createdAt` | integer | Creation time of account change details, milliseconds; this field is used for time filtering in this interface | Use the balance before and after the account change returned by the interface. Different changeType have different semantics, and it cannot be assumed that each amount is equal to walletBalanceAfter − walletBalanceBefore. The display/summary of ledger records should retain the type and detail identity. Here's an example of the format, using a fictitious ID and amount: ```json { "code": 0, "message": "success", "data": { "items": [ { "platformUserId": "1188041528", "entityType": "ACCOUNT_LEDGER", "entityId": "900001", "data": { "ledgerId": "ledger-example-001", "symbol": "BTCUSDT", "assetType": "USDT", "changeType": "HANDLING_FEE", "amount": "-0.10000000", "walletBalanceBefore": "100.00000000", "walletBalanceAfter": "99.90000000", "frozenBalanceBefore": "0.00000000", "frozenBalanceAfter": "0.00000000", "referenceId": "800001", "createdAt": 1791590400000 } } ], "nextCursor": "", "hasMore": false } } ``` ## Example response envelope This is an illustrative empty page, not a sample of a completed trade. Resource-specific field tables above describe populated `items[].data`. ```json {"code":0,"message":"success","data":{"items":[],"nextCursor":"","hasMore":false}} ``` ## Source and related guides * [Official v0.3.0 source](https://github.com/6mm-com/agent-java-sdk/tree/54aa3c1) * [Query overview and pagination](/sdk/agent-sdk/java/perpetual-queries) * [Funding wallet](/sdk/agent-sdk/java/funding-wallet) * [Upgrade guide](/sdk/agent-sdk/java/upgrade)