Flink学习笔记——Environment

Flink有以下几种Environment

1. 批处理Environment，ExecutionEnvironment

ExecutionEnvironment env = ExecutionEnvironment.getExecutionEnvironment();

2.流处理Environment，StreamExecutionEnvironment

StreamExecutionEnvironment env = StreamExecutionEnvironment.getExecutionEnvironment();

3. 本机Environment，LocalEnvironment

ExecutionEnvironment env = LocalEnvironment.getExecutionEnvironment();

4. java集合Environment，CollectionEnvironment

ExecutionEnvironment env = CollectionEnvironment.getExecutionEnvironment();

Ref

https://www.yuque.com/cuteximi/base/flink-02?language=en-us

　　

创建Environment的方法

1. getExecutionEnvironment ，含义就是本地运行就是
    createLocalEnvironment，如果是通过client提交到集群上，就返回集群的环境

Creates an execution environment that represents the context in which the program is currently executed.
 * If the program is invoked standalone, this method returns a local execution environment, as returned by
 * {@link #createLocalEnvironment()}. If the program is invoked from within the command line client to be
 * submitted to a cluster, this method returns the execution environment of this cluster.

Ref

https://github.com/apache/flink/blob/master/flink-java/src/main/java/org/apache/flink/api/java/ExecutionEnvironment.java

2. createLocalEnvironment ，返回本地执行环境，需要在调用时指定默认的并行度，比如

LocalStreamEnvironment env1 = StreamExecutionEnvironment.createLocalEnvironment(1);

LocalEnvironment env2 = ExecutionEnvironment.createLocalEnvironment(1);

3. createRemoteEnvironment， 返回集群执行环境，将 Jar 提交到远程服务器。需要在调用时指定 JobManager 的 IP 和端口号，并指定要在集群中运行的 Jar 包，比如

StreamExecutionEnvironment env1 = StreamExecutionEnvironment.createRemoteEnvironment("127.0.0.1", 8080, "/path/word_count.jar");

ExecutionEnvironment env2 = ExecutionEnvironment.createRemoteEnvironment("127.0.0.1", 8080, "/path/word_count.jar");