### Question:
SingletonIndexCursor extends AbstractIndexCursor<V> { @Override public boolean available() { return onSingleton; } SingletonIndexCursor( PartitionTxn partitionTxn, IndexEntry<V, String> singleton ); @Override boolean available(); @Override void beforeFirst(); @Override void afterLast(); @Override boolean first(); @Override boolean last(); @Override boolean isFirst(); @Override boolean isLast(); @Override boolean isAfterLast(); @Override boolean isBeforeFirst(); @Override boolean previous(); @Override boolean next(); IndexEntry<V, String> get(); @Override void close(); @Override void close( Exception cause );  }### Answer:
@Test public void testAvailable() throws Exception { assertFalse( indexCursor.available() ); indexCursor.first(); assertTrue( indexCursor.available() ); indexCursor.last(); assertTrue( indexCursor.available() ); indexCursor.afterLast(); assertFalse( indexCursor.available() ); indexCursor.beforeFirst(); assertFalse( indexCursor.available() ); }