question: public void ensureCapacity ( int minimumCapacity ) { if ( minimumCapacity <= _capacity ) return ; if ( minimumCapacity > 0x1000 ) { _capacity = ( minimumCapacity + 0xfff ) & ~ 0xfff ; } else { while ( _capacity < minimumCapacity ) { _capacity += _capacity ; } } byte [ ] bytes = new byte [ _capacity ] ; System . arraycopy ( _buffer , 0 , bytes , 0 , _length ) ; _buffer = bytes ; }
target:  Ensure the buffer can hold at least 'minimumCapacity' bytes.