question: public TransactionInput addInput ( TransactionOutput from ) { return addInput ( new TransactionInput ( params , this , from ) ) ; }
target:  Adds an input to this transaction that imports value from the given output. Note that this input is NOT complete and after every input is added with addInput() and every output is added with addOutput(), signInputs() must be called to finalize the transaction and finish the inputs off. Otherwise it won't be accepted by the network. Returns the newly created input.