Analyse following RPM build log snippet. Describe contents accurately, without speculation or suggestions for resolution.            
Your analysis must be as concise as possible, while keeping relevant information intact.
Snippet: 
[javac] error: Source option 1.3 is no longer supported. Use 8 or later./builddir/build/BUILD/bsf-2.4.0-build/bsf-2.4.0/build.xml:219: Compile failed; see the compiler error output for details.
Ant build failure related to javac tool.