Intelligent Contract Demo Analysis of digital currency development tutorial

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/*   Copyright IBM Corp All rights Reserved.   Licensed under the Apache License, Version 2.0 (the "License");   You are not a use of this file except in compliance with the License.   Obtain a copy of the License at            http://www.apache.org/licenses/lic ENSE-2.0   unless required by applicable law or agreed to in writing, software   distributed under the License I s distributed on a "as is" BASIS,   without warranties or CONDITIONS of any KIND, either express or implied.   See the License for the specific language governing permissions and   limitations under the License.   * *      package main     //warning-this Chaincode ' s ID was hard-coded in Chaincode_ Example04 to illustrate one by  //calling Chaincode from a chaincode. If This example is modified, chaincode_example04.go have  //to be modified as well with the new ID of Chaincode_examp Le02.  //CHAINCODE_EXAMPLE05 Show ' s how Chaincode ID can is passed in as a parameter instead of  //hard-coding.      Import (      "errors"       "FMT"       "StrConv" &nbsp ;        "Github.com/hyperledger/fabric/core/chaincode/shim"  )     // Simplechaincode Example Simple Chaincode implementation   type Simplechaincode struct { }      Func (t *simplechaincode) Init (stub *shim). Chaincodestub, function string, args []string] ([]byte, error) {      var A, B string    //Enti Ties       var aval, Bval Int//Asset Holdings       VAR err error      &nbs P   If Len (args)! = 4 {          return nil, errors. New ("Incorrect number of arguments. Expecting 4 ")      }         //Initialize the Chaincode     &NBSP A = args[0]       Aval, err = StrConv. Atoi (Args[1])       If err! = Nil {          return nil, errors. New ("Expecting integer value for asset holding")      }       B = args[2]     &NB Sp Bval, err = StrConv. Atoi (Args[3])       If err! = Nil {          return nil, errors. New ("Expecting integer value for asset holding")      }       FMT. Printf ("Aval =%d, Bval =%d\n", Aval, Bval)         //Write the state to the ledger   &NB Sp   Err = stub. Putstate (A, []byte (StrConv). Itoa (Aval))       If err! = Nil {          return nil, err       }          err = stub. Putstate (B, []byte (StrConv). Itoa (Bval))       If err! = Nil {          return nil, err       }         return nil, nil  }     //Transaction makes payment of X units fro M A to B   func (t *simplechaincode) Invoke (stub *shim. Chaincodestub, function string, args []string] ([]byte, error) {      if function = = "Delete" {  &NB Sp      //Deletes an entity from it state           return t.delete (stub, args) &n Bsp              var A, B string    //entities       VAR aval, Bval INT//Asset Holdings       var X int          //Transaction value