In building eclipse code, I have this “Build path specifies …” error.

Build path specifies execution environment J2SE-1.4. There are no JREs installed in the workspace that are strictly compatible with this environment.
Googling to find this post : java build path problems to add J2SE-1.4 execution environments.

And checked Java SE 7 is installed correctly.

However, I still get the error. What might be wrong?
I have this information with java -version in my command line.
java version "1.7.0_07"
Java(TM) SE Runtime Environment (build 1.7.0_07-b10)
Java HotSpot(TM) 64-Bit Server VM (build 23.3-b01, mixed mode)
You can try to go to
Project|Properties, then Choose theJava Build Path,chose the current
JRE System Library, and choose Remove.Select
Add Library, and under theJRE System Library category, select your system library;try to choose the
Workspace default JRE