openzeppelin-contracts/contracts/examples/SampleCrowdsale.sol

pragma solidity ^0.4.23;

import "../crowdsale/validation/CappedCrowdsale.sol";
import "../crowdsale/distribution/RefundableCrowdsale.sol";
import "../crowdsale/emission/MintedCrowdsale.sol";
import "../token/ERC20/MintableToken.sol";


/**
 * @title SampleCrowdsaleToken
 * @dev Very simple ERC20 Token that can be minted.
 * It is meant to be used in a crowdsale contract.
 */
contract SampleCrowdsaleToken is MintableToken {

  string public constant name = "Sample Crowdsale Token"; // solium-disable-line uppercase
  string public constant symbol = "SCT"; // solium-disable-line uppercase
  uint8 public constant decimals = 18; // solium-disable-line uppercase

}


/**
 * @title SampleCrowdsale
 * @dev This is an example of a fully fledged crowdsale.
 * The way to add new features to a base crowdsale is by multiple inheritance.
 * In this example we are providing following extensions:
 * CappedCrowdsale - sets a max boundary for raised funds
 * RefundableCrowdsale - set a min goal to be reached and returns funds if it's not met
 *
 * After adding multiple features it's good practice to run integration tests
 * to ensure that subcontracts works together as intended.
 */
contract SampleCrowdsale is CappedCrowdsale, RefundableCrowdsale, MintedCrowdsale {

  constructor(
    uint256 _openingTime,
    uint256 _closingTime,
    uint256 _rate,
    address _wallet,
    uint256 _cap,
    MintableToken _token,
    uint256 _goal
  )
    public
    Crowdsale(_rate, _wallet, _token)
    CappedCrowdsale(_cap)
    TimedCrowdsale(_openingTime, _closingTime)
    RefundableCrowdsale(_goal)
  {
    //As goal needs to be met for a successful crowdsale
    //the value needs to less or equal than a cap which is limit for accepted funds
    require(_goal <= _cap);
  }
}