<pluginManagement>
            <plugins>
                <plugin>
                    <groupId>org.apache.maven.plugins</groupId>
                    <artifactId>maven-compiler-plugin</artifactId>
                    <version>3.3</version>
                    <
 
configuration>
                        <source>1.8</source>
                        <target>1.8</target>
                        <encoding>UTF-8</encoding>
                        <testIncludes>
                            <testInclude>none</testInclude
 
>
                        </testIncludes>
                    </configuration>
                </plugin>
              
        </pluginManagement>

插入上述代碼 修改成1.8即可

Maven項目Update Project...後JRE System Library會自動變回1.5解決辦法