Resource specification not allowed here for source level below 1.7

Despite of the fact that you are using Java 1.7 you can compile source code as if you had compiler from Java 1.6 (this can be useful for example for cross-compilation). As Shivam Tiwari said in Eclipse you can change it in window->preferences->java->Compiler Compiler

If you are using Maven you should add the following plugin:

<plugin>
  <groupId>org.apache.maven.plugins</groupId>
  <artifactId>maven-compiler-plugin</artifactId>
  <version>2.5.1</version>
  <configuration>
    <source>1.7</source>
    <target>1.7</target>
  </configuration>
</plugin>

In Eclipse. Go to Project->Properties->Click on Java Compiler and change Compiler compliance level to 1.8 or above. It works for me many times.