lambda expressions are not supported at this language level intellij

環境：intellij 14.0.2， jdk 1.8

編譯錯誤：lambda expressions are not supported at this language level intellij

操作1：（如果刪除了專案檔案，如.idea .iml, 下次開啟專案需重新配置）

To compile with Java 8 (lambdas etc) in IntelliJ;

• CTRL + ALT + SHIFT + S or File / Project Structure

• Open Project tab

• Set Project SDK to compatible java version (1.8)

• Set Project language level to 8

• Open Modules tab

• Set Language level to 8, click OK

• CTRL + ALT + S or File / Settings

• Build, Execution, Deployment / Compiler / Java Compiler

• Change Target bytecode version to 1.8, click OK

操作2: （一次配置永久生效）

add the following content to pom.xml

<build>
    <plugins>
        <plugin>
            <groupId>org.apache.maven.plugins</groupId>
            <artifactId>maven-compiler-plugin</artifactId>
            <version>3.6.1</version>
            <configuration>
                <source>1.8</source>
                <target>1.8</target>
            </configuration>
        </plugin>
    </plugins>
</build>

參考：

http://stackoverflow.com/questions/22703412/java-lambda-expressions-not-supported-at-this-language-level