请使用flinkcdc的api方式将pg数据库写入到starrocks数据库中，请使用java代码实现

好的，以下是使用Flink CDC API将PG数据库写入StarRocks数据库的Java代码实现，供参考：

import org.apache.flink.api.common.functions.MapFunction;
import org.apache.flink.streaming.api.environment.StreamExecutionEnvironment;
import org.apache.flink.table.api.EnvironmentSettings;
import org.apache.flink.table.api.bridge.java.StreamTableEnvironment;
import org.apache.flink.table.api.bridge.java.internal.StreamTableEnvironmentImpl;
import org.apache.flink.table.api.internal.TableEnvironmentInternal;
import org.apache.flink.table.expressions.Expression;
import org.apache.flink.table.expressions.UnresolvedFieldReferenceExpression;
import org.apache.flink.table.types.logical.RowType;
import org.apache.flink.types.Row;

import java.util.Arrays;

public class PgToStarRocks {

    public static void main(String[] args) throws Exception {
        final StreamExecutionEnvironment env = StreamExecutionEnvironment.getExecutionEnvironment();
        EnvironmentSettings settings = EnvironmentSettings.newInstance().useBlinkPlanner().inStreamingMode().build();
        StreamTableEnvironment tEnv = StreamTableEnvironment.create(env, settings);

        // PG 数据库连接信息
        String pgUrl = "jdbc:postgresql://localhost:5432/pg_db";
        String pgUsername = "postgres";
        String pgPassword = "postgres";
        String pgTable = "pg_table";

        // StarRocks 数据库连接信息
        String starRocksUrl = "jdbc:mysql://localhost:9030/starrocks_db";
        String starRocksUsername = "root";
        String starRocksPassword = "root";
        String starRocksTable = "starrocks_table";

        // 定义 RowType
        RowType rowType = new RowType(
                Arrays.asList(
                        new RowType.RowField("id", new RowType.IntType()),
                        new RowType.RowField("name", new RowType.VarCharType(50)),
                        new RowType.RowField("age", new RowType.IntType())
                )
        );

        // 创建 PG 数据源表
        tEnv.executeSql(String.format("CREATE TABLE pg_source_table (id INT, name VARCHAR(50), age INT) WITH ('connector'='jdbc', 'url'='%s', 'table-name'='%s', 'username'='%s', 'password'='%s')", pgUrl, pgTable, pgUsername, pgPassword));

        // 创建 StarRocks 目标表
        tEnv.executeSql(String.format("CREATE TABLE starrocks_sink_table (id INT, name VARCHAR(50), age INT) WITH ('connector'='jdbc', 'url'='%s', 'table-name'='%s', 'username'='%s', 'password'='%s')", starRocksUrl, starRocksTable, starRocksUsername, starRocksPassword));

        // 使用 CDC API 读取 PG 数据源表
        Expression[] fieldNames = new Expression[] {
                new UnresolvedFieldReferenceExpression("id"),
                new UnresolvedFieldReferenceExpression("name"),
                new UnresolvedFieldReferenceExpression("age")
        };
        tEnv.createTable("pg_source", tEnv.fromChangelogSource("pg_source_table").schema(rowType).toChangelogStream(), fieldNames);

        // 将读取的数据写入 StarRocks 目标表
        tEnv.from("pg_source")
                .map(new MapFunction<Row, Row>() {
                    @Override
                    public Row map(Row value) throws Exception {
                        return value;
                    }
                })
                .executeInsert("starrocks_sink_table");

        env.execute("PgToStarRocks");
    }

}

注意：这里使用了 Flink 1.14.0 版本的 API，需要确保您的 Flink 环境已安装该版本的 Flink 和相应的 JDBC 驱动程序。