Multiple users on the blockchain can jointly participate in the development of smart contracts,and the rights and obligations of both parties are clearly defined in the contract agreement.After both parties agree on the content and objectives of the contract,By developers converting these protocols into code,the code contains conditions that trigger automatic contract execution.
当编码完成后，智能合约就会被上传到区块链上，即全网验证节点都会接收这份合约信息。
区块链等技术的参与。区块链是Web3.0最突出的关键技术，助力安全、透明和防篡改的交易。Web3.0同时也包含其他机制促进和推动去中心化，如云计算、AR Cloud和其他网络空间关键技术等；
//SPDX-License-Identifier:BUSL-1.1
pragma solidity=0.7.6;
import'./interfaces/IUniswapV3Factory.sol';
import'./UniswapV3PoolDeployer.sol';
import'./NoDelegateCall.sol';
import'./UniswapV3Pool.sol';
///title Canonical Uniswap V3 factory
///notice Deploys Uniswap V3 pools and manages ownership and control over pool protocol fees
contract UniswapV3Factory is IUniswapV3Factory,UniswapV3PoolDeployer,NoDelegateCall{
///inheritdoc IUniswapV3Factory
address public override owner;
///inheritdoc IUniswapV3Factory
mapping(uint24=>int24)public override feeAmountTickSpacing;
///inheritdoc IUniswapV3Factory
mapping(address=>mapping(address=>mapping(uint24=>address)))public override getPool;
constructor(){
owner=msg.sender;
emit OwnerChanged(address(0),msg.sender);
feeAmountTickSpacing[500]=10;
emit FeeAmountEnabled(500,10);
feeAmountTickSpacing[3000]=60;
emit FeeAmountEnabled(3000,60);
feeAmountTickSpacing[10000]=200;
emit FeeAmountEnabled(10000,200);
}
///inheritdoc IUniswapV3Factory
function createPool(
address tokenA,
address tokenB,
uint24 fee
)external override noDelegateCall returns(address pool){
require(tokenA!=tokenB);
(address token0,address token1)=tokenA<tokenB?(tokenA,tokenB):(tokenB,tokenA);
require(token0!=address(0));
int24 tickSpacing=feeAmountTickSpacing[fee];
require(tickSpacing!=0);
require(getPool[token0][token1][fee]==address(0));
pool=deploy(address(this),token0,token1,fee,tickSpacing);
getPool[token0][token1][fee]=pool;
//populate mapping in the reverse direction,deliberate choice to avoid the cost of comparing addresses
getPool[token1][token0][fee]=pool;
emit PoolCreated(token0,token1,fee,tickSpacing,pool);
}
///inheritdoc IUniswapV3Factory
function setOwner(address _owner)external override{
require(msg.sender==owner);
emit OwnerChanged(owner,_owner);
owner=_owner;
}
///inheritdoc IUniswapV3Factory
function enableFeeAmount(uint24 fee,int24 tickSpacing)public override{
require(msg.sender==owner);
require(fee<1000000);
//tick spacing is capped at 16384 to prevent the situation where tickSpacing is so large that
//TickBitmap#nextInitializedTickWithinOneWord overflows int24 container from a valid tick
//16384 ticks represents a>5x price change with ticks of 1 bips
require(tickSpacing>0&&tickSpacing<16384);
require(feeAmountTickSpacing[fee]==0);
feeAmountTickSpacing[fee]=tickSpacing;
emit FeeAmountEnabled(fee,tickSpacing);
}
}
