### Question:
UnusedVariable extends BugChecker implements CompilationUnitTreeMatcher { private static boolean exemptedByName(Name name) { String nameString = name.toString(); return Ascii.toLowerCase(nameString).startsWith(EXEMPT_PREFIX) || EXEMPT_NAMES.contains(nameString); } UnusedVariable(ErrorProneFlags flags); @Override Description matchCompilationUnit(CompilationUnitTree tree, VisitorState state);  }### Answer:
@Test public void exemptedByName() { helper .addSourceLines( "Unuseds.java", "package unusedvars;", "class ExemptedByName {", " private int unused;", " private int unusedInt;", " private static final int UNUSED_CONSTANT = 5;", " private int ignored;", "}") .doTest(); }