### Build a Log Service Client

Source: https://github.com/aliyun/aliyun-log-java-sdk/blob/master/README_EN.md

Initializes the Log Service client with host, access ID, and access key. Optionally enables metric store URL for improved performance with metricstores.

```java
String accessId = "your_access_id";
String accessKey = "your_access_key";
String host = "your_endpoint";
Client client = new Client(host, accessId, accessKey);

// Notes on UseMetricStoreUrl:
// 1. The setting is global at the Client level. It auto-appends the hash key (METRICS_STORE_AUTO_HASH).
//    Use it only when the destination Store is a Metricstore — for Metricstores with a large
//    time-series cardinality it improves time-series query performance.
// 2. When both Logstore and Metricstore writes coexist, the caller must manually set HashKey
//    to METRICS_STORE_AUTO_HASH to trigger the auto-hash write path for the Metricstore.
client.setUseMetricStoreUrl(true);
```

--------------------------------

### Create a Logstore

Source: https://github.com/aliyun/aliyun-log-java-sdk/blob/master/README_EN.md

Creates a new Logstore within a specified project. Configures the Logstore's time-to-live (TTL) and shard count.

```java
String project = "your_project_name";
String logstore = "your_logstore";
int ttl_in_day = 3;
int shard_count = 10;
LogStore store = new LogStore(logstore, ttl_in_day, shard_count);
CreateLogStoreResponse res = client.CreateLogStore(project, store);
```

--------------------------------

### Maven Dependency with Protobuf Exclusion

Source: https://github.com/aliyun/aliyun-log-java-sdk/blob/master/README_EN.md

Provides a Maven dependency configuration for the Aliyun Log SDK that excludes the default protobuf-java dependency to resolve conflicts.

```xml
<dependency>
    <groupId>com.aliyun.openservices</groupId>
    <artifactId>aliyun-log</artifactId>
    <version>0.6.97</version>
    <classifier>jar-with-dependencies</classifier>
    <exclusions>
        <exclusion>
            <groupId>com.google.protobuf</groupId>
            <artifactId>protobuf-java</artifactId>
        </exclusion>
    </exclusions>
</dependency>
```

--------------------------------

### Maven Dependency for Aliyun Log SDK

Source: https://github.com/aliyun/aliyun-log-java-sdk/blob/master/README_EN.md

Specifies the Maven dependency required to include the Aliyun Log Java SDK in your project.

```xml
<dependency>
    <groupId>com.aliyun.openservices</groupId>
    <artifactId>aliyun-log</artifactId>
    <version>0.6.97</version>
</dependency>
```

--------------------------------

### Write Data to Logstore

Source: https://github.com/aliyun/aliyun-log-java-sdk/blob/master/README_EN.md

Writes multiple log items to a specified Logstore. Each log item includes a timestamp and key-value pairs. Includes error handling for LogException.

```java
int numLogGroup = 10;
/**
 * Send numLogGroup log packets to Log Service. Each packet contains 2 log lines.
 */
for (int i = 0; i < numLogGroup; i++) {
    List<LogItem> logGroup = new ArrayList<LogItem>();
    LogItem logItem = new LogItem((int) (new Date().getTime() / 1000));
    logItem.PushBack("level", "info");
    logItem.PushBack("name", String.valueOf(i));
    logItem.PushBack("message", "it's a test message");

    logGroup.add(logItem);

    LogItem logItem2 = new LogItem((int) (new Date().getTime() / 1000));
    logItem2.PushBack("level", "error");
    logItem2.PushBack("name", String.valueOf(i));
    logItem2.PushBack("message", "it's a test message");
    logGroup.add(logItem2);

    try {
        client.PutLogs(project, logStore, topic, logGroup, "");
    } catch (LogException e) {
        System.out.println("error code :" + e.GetErrorCode());
        System.out.println("error message :" + e.GetErrorMessage());
        System.out.println("error requestId :" + e.GetRequestId());
        throw e;
    }

}
```

--------------------------------

### Read Data from Logstore

Source: https://github.com/aliyun/aliyun-log-java-sdk/blob/master/README_EN.md

Reads log data from a specific shard within a Logstore. It retrieves a cursor for the initial read and then iteratively fetches batches of logs using cursors.

```java
int shardId = 0;  // Read data from shard 0 only
GetCursorResponse res;
try {
    // Cursor for the first batch of logs received in the last hour
    long fromTime = (int)(System.currentTimeMillis()/1000.0 - 3600);
    res = client.GetCursor(project, logStore, shardId, fromTime);
    System.out.println("shard_id:" + shardId + " Cursor:" + res.GetCursor());
} catch (LogException e) {
    e.printStackTrace();
}

String cursor = res.GetCursor();
while(true) {
    BatchGetLogResponse logDataRes = client.BatchGetLog(
    project, logStore, shardId, 100, cursor);
    // Data returned by the server
    List<LogGroupData> logGroups = logDataRes.GetLogGroups();

    String nextCursor = logDataRes.GetNextCursor();  // Cursor for the next read
    System.out.print("The Next cursor:" + nextCursor);
    if (cursor.equals(nextCursor)) {
        break;
    }
    cursor = nextCursor;
}
```

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