### Question:
ELContextDecorator extends ELContext { @Override public FunctionMapper getFunctionMapper() { return this.elContext.getFunctionMapper(); } ELContextDecorator(ELContext elContext); @Override void setPropertyResolved(boolean resolved); @Override boolean isPropertyResolved(); @Override @SuppressWarnings("rawtypes") void putContext(Class key, Object contextObject); @Override @SuppressWarnings("rawtypes") Object getContext(Class key); @Override Locale getLocale(); @Override void setLocale(Locale locale); @Override ELResolver getELResolver(); @Override FunctionMapper getFunctionMapper(); @Override VariableMapper getVariableMapper();  }### Answer:
@Test public void shouldDecorateGetFunctionMapper() throws Exception { FunctionMapper funcationMapper = mock(FunctionMapper.class); given(this.decorated.getFunctionMapper()).willReturn(funcationMapper); FunctionMapper actual = this.decorator.getFunctionMapper(); assertThat(actual, is(funcationMapper)); verify(this.decorated).getFunctionMapper(); }