IDEA -source 1.5 中不支持 lambda 表达式解决方法

一直在用scala编写Spark或者Flink代码，对于Java的lambda表达式一直认为没有前者一直点(".")下去方便，偶然用后者写代码中间出现一些小的设置问题，记录一下：

示例代码

......
final LocalEnvironment env = ExecutionEnvironment.createLocalEnvironment();
final DataSource&lt;Integer&gt; source = env.fromElements(1, 2, 3, 4, 5, 2, 3, 4, 5, 2, 3, 4, 5, 2, 3, 4, 5, 2, 3, 4, 5);
source
    .map(i-&gt;i*i)
    .print();
......

......

final LocalEnvironment env = ExecutionEnvironment.createLocalEnvironment();

final DataSource<Integer> source = env.fromElements(1, 2, 3, 4, 5, 2, 3, 4, 5, 2, 3, 4, 5, 2, 3, 4, 5, 2, 3, 4, 5);

source

.map(i->i*i)

.print();

......

Error:(18, 15) java: -source 1.5 中不支持 lambda 表达式

Information:java: Errors occurred while compiling module 'flink-suit'
Information:javac 1.8.0_181 was used to compile java sources
Information:Module "flink-suit" was fully rebuilt due to project configuration/dependencies changes
Information:2018/10/1 下午7:17 - Compilation completed with 1 error and 4 warnings in 4s 948ms
Warning:scalac: there was one deprecation warning; re-run with -deprecation for details
Warning:java: 源值1.5已过时, 将在未来所有发行版中删除
Warning:java: 目标值1.5已过时, 将在未来所有发行版中删除
Warning:java: 要隐藏有关已过时选项的警告, 请使用 -Xlint:-options。
/Users/neters/computing/flink-suit/src/main/java/com/yidian/data/api/LambdaAPI.java
Error:(18, 15) java: -source 1.5 中不支持 lambda 表达式
  (请使用 -source 8 或更高版本以启用 lambda 表达式)

Information:java: Errors occurred while compiling module 'flink-suit'

Information:javac 1.8.0_181 was used to compile java sources

Information:Module "flink-suit" was fully rebuilt due to project configuration/dependencies changes

Information:2018/10/1 下午7:17 - Compilation completed with 1 error and 4 warnings in 4s 948ms

Warning:scalac: there was one deprecation warning; re-run with -deprecation for details

Warning:java: 源值1.5已过时, 将在未来所有发行版中删除

Warning:java: 目标值1.5已过时, 将在未来所有发行版中删除

Warning:java: 要隐藏有关已过时选项的警告, 请使用 -Xlint:-options。

/Users/neters/computing/flink-suit/src/main/java/com/yidian/data/api/LambdaAPI.java

Error:(18, 15) java: -source 1.5 中不支持 lambda 表达式

(请使用 -source 8 或更高版本以启用 lambda 表达式)

解决方法：

右键点击工程名->"Open Module Setting"

Error:java: Compilation failed: internal java compiler error

Information:java: javacTask: 源发行版 1.8 需要目标发行版 1.8
Information:java: Errors occurred while compiling module 'flink-suit'
Information:javac 1.8.0_181 was used to compile java sources
Information:2018/10/1 下午7:17 - Compilation completed with 1 error and 1 warning in 2s 899ms
Error:java: Compilation failed: internal java compiler error
Warning:scalac: there was one deprecation warning; re-run with -deprecation for details