question: protected final void expandCapacity ( int minimumCapacity ) { int newCapacity = Math . max ( 2 * _buffer . length , minimumCapacity ) ; char [ ] chars = new char [ newCapacity ] ; System . arraycopy ( buffer ( ) , 0 , chars , 0 , _buffer . length ) ; _buffer = chars ; }
target:  Expands the capacity to a new value.