Flink自定义Sink系列2

Flink自定义Sink系列之JDBC前言一、代码如下总结

使用flink的官方JDBC连接器创建数据库的连接Sink

代码如下（示例）：

public class JDBCSink {

    public  SinkFunction getSinkFunction(String sql){
        return JdbcSink.sink(sql,
                new JdbcStatementBuilder() {
                    @Override
                    public void accept(PreparedStatement preparedStatement, T t) throws SQLException {
                        Class aClass = t.getClass();
                        Field[] fields = aClass.getDeclaredFields();
                        Object o=null;
                        for (int i = 0; i < fields.length; i++) {
                            try {
                                fields[i].setAccessible(true);
                                o = fields[i].get(t);
                            } catch (IllegalAccessException e) {
                                e.printStackTrace();
                            }
                            preparedStatement.setObject(i+1,o);
                        }
                    }
                }, JdbcExecutionOptions.builder()
                        .withBatchSize(1000)
                        .withBatchIntervalMs(200)
                        .withMaxRetries(5)
                        .build()
        ,new JdbcConnectionOptions.JdbcConnectionOptionsBuilder()
        .withUrl("jdbc:postgresql://dbhost:5432/postgresdb")
        .withDriverName("org.postgresql.Driver")
        .withUsername("someUser")
        .withPassword("somePassword")
        .build());
    }
}

注意这里可以点进去源码看到，后面的实例不是new出来的，而是通过Build来创建的，但是这两个Build是有区别的，一个是static final,一个是staic,通过static final修饰，其实原理是一样的都是通过内部类来实现的

public static class JdbcConnectionOptionsBuilder {
		private String url;
		private String driverName;
		private String username;
		private String password;

		public JdbcConnectionOptionsBuilder withUrl(String url) {
			this.url = url;
			return this;
		}

		public JdbcConnectionOptionsBuilder withDriverName(String driverName) {
			this.driverName = driverName;
			return this;
		}

		public JdbcConnectionOptionsBuilder withUsername(String username) {
			this.username = username;
			return this;
		}

		public JdbcConnectionOptionsBuilder withPassword(String password) {
			this.password = password;
			return this;
		}

		public JdbcConnectionOptions build() {
			return new JdbcConnectionOptions(url, driverName, username, password);
		}
	}

第二种

    public static Builder builder() {
		return new Builder();
	}

	
	public static final class Builder {
		private long intervalMs = DEFAULT_INTERVAL_MILLIS;
		private int size = DEFAULT_SIZE;
		private int maxRetries = DEFAULT_MAX_RETRY_TIMES;

		public Builder withBatchSize(int size) {
			this.size = size;
			return this;
		}

		public Builder withBatchIntervalMs(long intervalMs) {
			this.intervalMs = intervalMs;
			return this;
		}

		public Builder withMaxRetries(int maxRetries) {
			this.maxRetries = maxRetries;
			return this;
		}

		public JdbcExecutionOptions build() {
			return new JdbcExecutionOptions(intervalMs, size, maxRetries);
		}
	}

对于内部类的使用是通过
new 主类.内部类().xxxx这样去实例化的。

以上就是对flink jdbcsink的简单记录！