江陵月色

Java与智能合约交互

合约代码

先准备好一份合约代码如下：

合约的功能是实现一个简单的用户管理系统，包括

注册功能
登录功能
修改密码
获得用户信息
获得系统用户总数

pragma solidity >= 0.5.0;
contract UserManagerment {
    // 用户结构体
    struct User {
        address ethAddr;
        string userName;
        bytes32 password;
    }
    // 合约部署者地址
    address host;
    // 保存所有用户
    User[] userInfos;
    // 用户名到是否注册的映射
    mapping(string => bool) registerPool;
    // 用户名到用户的映射
    mapping(string => User) userPool;
    // 构造函数 设置合约拥有者地址
    constructor() public {
        host = msg.sender;
    }
    // 登录功能
    function doLogin(string memory userName, string memory password)  public view returns (bool) {
        return userPool[userName].password == keccak256(abi.encode(password));
    }
    // 注册检测
    function checkRegister(string memory userName)  public view returns (bool) {
        return registerPool[userName];
    }
	// 用户注册
    function register(address ethAddr, string memory  userName, string memory password) public {
        // 检查用户是否注册 当 require() 中的条件值为假时抛出异常,异常信息为：“用户已经注册”
        require(!checkRegister(userName),"用户已经注册！");
        // 保存注册信息
		userPool[userName] = User(ethAddr, userName, keccak256(abi.encode(password)));
        // 设置用户名为已经注册
		registerPool[userName] = true;
        // 添加到用户数组中
        userInfos.push(userPool[userName]);
    }
    // 更新密码
    function updatePassword(string memory userName, string memory newPwd) public {
        // keccak256加密
		userPool[userName].password = keccak256(abi.encode(newPwd));
    }
    // 获得用户信息
    function getUserInfoByUserName(string memory userName) public view returns (address,string memory){
        require(registerPool[userName],"未查到该用户信息");
        User storage user = userPool[userName];
        return (user.ethAddr,user.userName);
    }
    // 获得所有用户信息
    function getAllUserInfos(uint index)public view returns (address,string memory){
        // 检查下表范围
        require(index < userInfos.length,"下标越界");
        // 检查用户权限，只有合约创建者才能执行该操作
        require(msg.sender == host,"非法访问");
        // 取出用户信息
        User storage user = userInfos[index];
        // 返回数据
        return (user.ethAddr,user.userName);
    }
    // 获得系统用户数
    function getTotalUserNum() public view returns (uint){
        // 检查用户权限，只有合约创建者才能执行该操作
        require(msg.sender == host,"非法访问");
        return userInfos.length;
    }
}

编译合约

由于使用的VS Code编辑器，安装的插件solidity0.0.72可以直接按F5编译

编译后，在文件夹根目录生成了bin文件夹。里头的内容如下：

java打包合约

下载web3j命令行工具

下载连接：点击直达
解压工具包

注：可以将bin文件夹路径添加到系统环境变量中，这样省得之后进入bin目录使用命令

进入文件夹bin目录

输入如下命令：

web3j solidity generate /path/to/.bin /path/to/.abi -o /path/to/src/main/java -p com.your.organisation.name

说明：

/path/to/.bin 智能合约编译后的生成物
/path/to/.abi 智能合约编译后的生成物
-o /path/to/src/main/java 输出路径
-p com.your.organisation.name 打包的包名

举例：

web3j solidity generate E:\BlockChain\Solidity\bin\UserManagerment.bin E:\BlockChain\Solidity\bin\UserManagerment.abi  -o E:\Web3j -p com.my.contract

输出结果：

修改Java代码

上述操作生成的UserManagerment.java内容如下：

package com.my.contract;

import java.math.BigInteger;
import java.util.Arrays;
import java.util.Collections;

import org.web3j.abi.TypeReference;
import org.web3j.abi.datatypes.Function;
import org.web3j.abi.datatypes.Type;
import org.web3j.crypto.Credentials;
import org.web3j.protocol.Web3j;
import org.web3j.protocol.core.RemoteCall;
import org.web3j.protocol.core.methods.response.TransactionReceipt;
import org.web3j.tx.Contract;
import org.web3j.tx.TransactionManager;
import org.web3j.tx.gas.ContractGasProvider;

/**
 * 
 * Auto generated code.
 * 

 * Do not modify!
 * 

 * Please use the web3j
 * command line tools, or the
 * org.web3j.codegen.SolidityFunctionWrapperGenerator in the
 * codegen
 * module to update.
 *
 * 
 * Generated with web3j version 3.6.0.
 */
public class UserManagerment extends Contract {
	private static final String BINARY = "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	public static final String FUNC_CHECKREGISTER = "checkRegister";

	public static final String FUNC_DOLOGIN = "doLogin";

	public static final String FUNC_GETALLUSERINFOS = "getAllUserInfos";

	public static final String FUNC_GETTOTALUSERNUM = "getTotalUserNum";

	public static final String FUNC_GETUSERINFOBYUSERNAME = "getUserInfoByUserName";

	public static final String FUNC_REGISTER = "register";

	public static final String FUNC_UPDATEPASSWORD = "updatePassword";

	@Deprecated
	protected UserManagerment(String contractAddress, Web3j web3j, Credentials credentials, BigInteger gasPrice,
			BigInteger gasLimit) {
		super(BINARY, contractAddress, web3j, credentials, gasPrice, gasLimit);
	}

	protected UserManagerment(String contractAddress, Web3j web3j, Credentials credentials,
			ContractGasProvider contractGasProvider) {
		super(BINARY, contractAddress, web3j, credentials, contractGasProvider);
	}

	@Deprecated
	protected UserManagerment(String contractAddress, Web3j web3j, TransactionManager transactionManager,
			BigInteger gasPrice, BigInteger gasLimit) {
		super(BINARY, contractAddress, web3j, transactionManager, gasPrice, gasLimit);
	}

	protected UserManagerment(String contractAddress, Web3j web3j, TransactionManager transactionManager,
			ContractGasProvider contractGasProvider) {
		super(BINARY, contractAddress, web3j, transactionManager, contractGasProvider);
	}

	public static RemoteCall<UserManagerment> deploy(Web3j web3j, Credentials credentials,
			ContractGasProvider contractGasProvider) {
		return deployRemoteCall(UserManagerment.class, web3j, credentials, contractGasProvider, BINARY, "");
	}

	public static RemoteCall<UserManagerment> deploy(Web3j web3j, TransactionManager transactionManager,
			ContractGasProvider contractGasProvider) {
		return deployRemoteCall(UserManagerment.class, web3j, transactionManager, contractGasProvider, BINARY, "");
	}

	@Deprecated
	public static RemoteCall<UserManagerment> deploy(Web3j web3j, Credentials credentials, BigInteger gasPrice,
			BigInteger gasLimit) {
		return deployRemoteCall(UserManagerment.class, web3j, credentials, gasPrice, gasLimit, BINARY, "");
	}

	@Deprecated
	public static RemoteCall<UserManagerment> deploy(Web3j web3j, TransactionManager transactionManager,
			BigInteger gasPrice, BigInteger gasLimit) {
		return deployRemoteCall(UserManagerment.class, web3j, transactionManager, gasPrice, gasLimit, BINARY, "");
	}

	public RemoteCall<TransactionReceipt> checkRegister(String userName) {
		final Function function = new Function(FUNC_CHECKREGISTER,
				Arrays.<Type>asList(new org.web3j.abi.datatypes.Utf8String(userName)),
				Collections.<?>>emptyList());
		return executeRemoteCallTransaction(function);
	}

	public RemoteCall<TransactionReceipt> doLogin(String userName, String password) {
		final Function function = new Function(FUNC_DOLOGIN,
				Arrays.<Type>asList(new org.web3j.abi.datatypes.Utf8String(userName),
						new org.web3j.abi.datatypes.Utf8String(password)),
				Collections.<?>>emptyList());
		return executeRemoteCallTransaction(function);
	}

	public RemoteCall<TransactionReceipt> getAllUserInfos(BigInteger index) {
		final Function function = new Function(FUNC_GETALLUSERINFOS,
				Arrays.<Type>asList(new org.web3j.abi.datatypes.generated.Uint256(index)),
				Collections.<?>>emptyList());
		return executeRemoteCallTransaction(function);
	}

	public RemoteCall<TransactionReceipt> getTotalUserNum() {
		final Function function = new Function(FUNC_GETTOTALUSERNUM, Arrays.<Type>asList(),
				Collections.<?>>emptyList());
		return executeRemoteCallTransaction(function);
	}

	public RemoteCall<TransactionReceipt> getUserInfoByUserName(String userName) {
		final Function function = new Function(FUNC_GETUSERINFOBYUSERNAME,
				Arrays.<Type>asList(new org.web3j.abi.datatypes.Utf8String(userName)),
				Collections.<?>>emptyList());
		return executeRemoteCallTransaction(function);
	}

	public RemoteCall<TransactionReceipt> register(String ethAddr, String userName, String password) {
		final Function function = new Function(FUNC_REGISTER,
				Arrays.<Type>asList(new org.web3j.abi.datatypes.Address(ethAddr),
						new org.web3j.abi.datatypes.Utf8String(userName),
						new org.web3j.abi.datatypes.Utf8String(password)),
				Collections.<?>>emptyList());
		return executeRemoteCallTransaction(function);
	}

	public RemoteCall<TransactionReceipt> updatePassword(String userName, String newPwd) {
		final Function function = new Function(FUNC_UPDATEPASSWORD,
				Arrays.<Type>asList(new org.web3j.abi.datatypes.Utf8String(userName),
						new org.web3j.abi.datatypes.Utf8String(newPwd)),
				Collections.<?>>emptyList());
		return executeRemoteCallTransaction(function);
	}

	@Deprecated
	public static UserManagerment load(String contractAddress, Web3j web3j, Credentials credentials,
			BigInteger gasPrice, BigInteger gasLimit) {
		return new UserManagerment(contractAddress, web3j, credentials, gasPrice, gasLimit);
	}

	@Deprecated
	public static UserManagerment load(String contractAddress, Web3j web3j, TransactionManager transactionManager,
			BigInteger gasPrice, BigInteger gasLimit) {
		return new UserManagerment(contractAddress, web3j, transactionManager, gasPrice, gasLimit);
	}

	public static UserManagerment load(String contractAddress, Web3j web3j, Credentials credentials,
			ContractGasProvider contractGasProvider) {
		return new UserManagerment(contractAddress, web3j, credentials, contractGasProvider);
	}

	public static UserManagerment load(String contractAddress, Web3j web3j, TransactionManager transactionManager,
			ContractGasProvider contractGasProvider) {
		return new UserManagerment(contractAddress, web3j, transactionManager, contractGasProvider);
	}
}

代码内容介绍

合约二进制串

private static final String BINARY = "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";

我们定义的function名称

	public static final String FUNC_CHECKREGISTER = "checkRegister";

	public static final String FUNC_DOLOGIN = "doLogin";

	public static final String FUNC_GETALLUSERINFOS = "getAllUserInfos";

	public static final String FUNC_GETTOTALUSERNUM = "getTotalUserNum";

	public static final String FUNC_GETUSERINFOBYUSERNAME = "getUserInfoByUserName";

	public static final String FUNC_REGISTER = "register";

	public static final String FUNC_UPDATEPASSWORD = "updatePassword";

合约部署函数

  public static RemoteCall<UserManagerment> deploy(Web3j web3j, Credentials credentials,
			ContractGasProvider contractGasProvider) {
		return deployRemoteCall(UserManagerment.class, web3j, credentials, contractGasProvider, BINARY, "");
	}

	public static RemoteCall<UserManagerment> deploy(Web3j web3j, TransactionManager transactionManager,
			ContractGasProvider contractGasProvider) {
		return deployRemoteCall(UserManagerment.class, web3j, transactionManager, contractGasProvider, BINARY, "");
	}

	@Deprecated
	public static RemoteCall<UserManagerment> deploy(Web3j web3j, Credentials credentials, BigInteger gasPrice,
			BigInteger gasLimit) {
		return deployRemoteCall(UserManagerment.class, web3j, credentials, gasPrice, gasLimit, BINARY, "");
	}

	@Deprecated
	public static RemoteCall<UserManagerment> deploy(Web3j web3j, TransactionManager transactionManager,
			BigInteger gasPrice, BigInteger gasLimit) {
		return deployRemoteCall(UserManagerment.class, web3j, transactionManager, gasPrice, gasLimit, BINARY, "");
	}

合约加载函数

	@Deprecated
	public static UserManagerment load(String contractAddress, Web3j web3j, Credentials credentials,
			BigInteger gasPrice, BigInteger gasLimit) {
		return new UserManagerment(contractAddress, web3j, credentials, gasPrice, gasLimit);
	}

	@Deprecated
	public static UserManagerment load(String contractAddress, Web3j web3j, TransactionManager transactionManager,
			BigInteger gasPrice, BigInteger gasLimit) {
		return new UserManagerment(contractAddress, web3j, transactionManager, gasPrice, gasLimit);
	}

	public static UserManagerment load(String contractAddress, Web3j web3j, Credentials credentials,
			ContractGasProvider contractGasProvider) {
		return new UserManagerment(contractAddress, web3j, credentials, contractGasProvider);
	}

	public static UserManagerment load(String contractAddress, Web3j web3j, TransactionManager transactionManager,
			ContractGasProvider contractGasProvider) {
		return new UserManagerment(contractAddress, web3j, transactionManager, contractGasProvider);
	}

自定义的函数

public RemoteCall<TransactionReceipt> checkRegister(String userName) {
		final Function function = new Function(FUNC_CHECKREGISTER,
				Arrays.<Type>asList(new org.web3j.abi.datatypes.Utf8String(userName)),
				Collections.<?>>emptyList());
		return executeRemoteCallTransaction(function);
	}

	public RemoteCall<TransactionReceipt> doLogin(String userName, String password) {
		final Function function = new Function(FUNC_DOLOGIN,
				Arrays.<Type>asList(new org.web3j.abi.datatypes.Utf8String(userName),
						new org.web3j.abi.datatypes.Utf8String(password)),
				Collections.<?>>emptyList());
		return executeRemoteCallTransaction(function);
	}

	public RemoteCall<TransactionReceipt> getAllUserInfos(BigInteger index) {
		final Function function = new Function(FUNC_GETALLUSERINFOS,
				Arrays.<Type>asList(new org.web3j.abi.datatypes.generated.Uint256(index)),
				Collections.<?>>emptyList());
		return executeRemoteCallTransaction(function);
	}

	public RemoteCall<TransactionReceipt> getTotalUserNum() {
		final Function function = new Function(FUNC_GETTOTALUSERNUM, Arrays.<Type>asList(),
				Collections.<?>>emptyList());
		return executeRemoteCallTransaction(function);
	}

	public RemoteCall<TransactionReceipt> getUserInfoByUserName(String userName) {
		final Function function = new Function(FUNC_GETUSERINFOBYUSERNAME,
				Arrays.<Type>asList(new org.web3j.abi.datatypes.Utf8String(userName)),
				Collections.<?>>emptyList());
		return executeRemoteCallTransaction(function);
	}

	public RemoteCall<TransactionReceipt> register(String ethAddr, String userName, String password) {
		final Function function = new Function(FUNC_REGISTER,
				Arrays.<Type>asList(new org.web3j.abi.datatypes.Address(ethAddr),
						new org.web3j.abi.datatypes.Utf8String(userName),
						new org.web3j.abi.datatypes.Utf8String(password)),
				Collections.<?>>emptyList());
		return executeRemoteCallTransaction(function);
	}

	public RemoteCall<TransactionReceipt> updatePassword(String userName, String newPwd) {
		final Function function = new Function(FUNC_UPDATEPASSWORD,
				Arrays.<Type>asList(new org.web3j.abi.datatypes.Utf8String(userName),
						new org.web3j.abi.datatypes.Utf8String(newPwd)),
				Collections.<?>>emptyList());
		return executeRemoteCallTransaction(function);
	}

自定义的函数介绍

举例说明：
```
	public RemoteCall<TransactionReceipt> checkRegister(String userName) {
		final Function function = new Function(FUNC_CHECKREGISTER,
				Arrays.<Type>asList(new org.web3j.abi.datatypes.Utf8String(userName)),
				Collections.<?>>emptyList());
		return executeRemoteCallTransaction(function);
	}
```
这是自动生成的Java代码，但是好像有些问题。因为我们在合约中定义的函数是有返回值的。
- RemoteCall
  
  <> 中是函数的返回类型>
  
  TransactionReceipt 表示返回的是区块的信息
- Function()中有三个参数
  
  函数名称、输入参数、返回值
- return executeRemoteCallTransaction(function)
  
  表示执行远程调用，返回的是 TransactionReceipt

开始修改

举例：

	public RemoteCall<TransactionReceipt> checkRegister(String userName) {
		final Function function = new Function(FUNC_CHECKREGISTER,
				Arrays.<Type>asList(new org.web3j.abi.datatypes.Utf8String(userName)),
				Collections.<?>>emptyList());
		return executeRemoteCallTransaction(function);
	}

合约中我们定义的是返回Bool值，所以要修改如下几处内容：

修改后内容：

	public RemoteCall<Bool> checkRegister(String userName) {
		final Function function = new Function(FUNC_CHECKREGISTER,
				Arrays.<Type>asList(new org.web3j.abi.datatypes.Utf8String(userName)),
				Arrays.<?>>asList(new TypeReference<Bool>() {
				}));
		return executeRemoteCallSingleValueReturn(function);
	}

修改后完整代码

package com.mao.contract;

import java.math.BigInteger;
import java.util.Arrays;
import java.util.Collections;
import java.util.List;

import org.web3j.abi.TypeReference;
import org.web3j.abi.datatypes.Address;
import org.web3j.abi.datatypes.Bool;
import org.web3j.abi.datatypes.Function;
import org.web3j.abi.datatypes.Type;
import org.web3j.abi.datatypes.Utf8String;
import org.web3j.abi.datatypes.generated.Uint256;
import org.web3j.crypto.Credentials;
import org.web3j.protocol.Web3j;
import org.web3j.protocol.core.RemoteCall;
import org.web3j.protocol.core.methods.response.TransactionReceipt;
import org.web3j.tx.Contract;
import org.web3j.tx.TransactionManager;
import org.web3j.tx.gas.ContractGasProvider;

public class UserManagerment extends Contract {
	private static final String BINARY = "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";

	public static final String FUNC_CHECKREGISTER = "checkRegister";

	public static final String FUNC_DOLOGIN = "doLogin";

	public static final String FUNC_GETALLUSERINFOS = "getAllUserInfos";

	public static final String FUNC_GETTOTALUSERNUM = "getTotalUserNum";

	public static final String FUNC_GETUSERINFOBYUSERNAME = "getUserInfoByUserName";

	public static final String FUNC_REGISTER = "register";

	public static final String FUNC_UPDATEPASSWORD = "updatePassword";

	@Deprecated
	protected UserManagerment(String contractAddress, Web3j web3j, Credentials credentials, BigInteger gasPrice,
			BigInteger gasLimit) {
		super(BINARY, contractAddress, web3j, credentials, gasPrice, gasLimit);
	}

	protected UserManagerment(String contractAddress, Web3j web3j, Credentials credentials,
			ContractGasProvider contractGasProvider) {
		super(BINARY, contractAddress, web3j, credentials, contractGasProvider);
	}

	@Deprecated
	protected UserManagerment(String contractAddress, Web3j web3j, TransactionManager transactionManager,
			BigInteger gasPrice, BigInteger gasLimit) {
		super(BINARY, contractAddress, web3j, transactionManager, gasPrice, gasLimit);
	}

	protected UserManagerment(String contractAddress, Web3j web3j, TransactionManager transactionManager,
			ContractGasProvider contractGasProvider) {
		super(BINARY, contractAddress, web3j, transactionManager, contractGasProvider);
	}

	public static RemoteCall<UserManagerment> deploy(Web3j web3j, Credentials credentials,
			ContractGasProvider contractGasProvider) {
		return deployRemoteCall(UserManagerment.class, web3j, credentials, contractGasProvider, BINARY, "");
	}

	public static RemoteCall<UserManagerment> deploy(Web3j web3j, TransactionManager transactionManager,
			ContractGasProvider contractGasProvider) {
		return deployRemoteCall(UserManagerment.class, web3j, transactionManager, contractGasProvider, BINARY, "");
	}

	@Deprecated
	public static RemoteCall<UserManagerment> deploy(Web3j web3j, Credentials credentials, BigInteger gasPrice,
			BigInteger gasLimit) {
		return deployRemoteCall(UserManagerment.class, web3j, credentials, gasPrice, gasLimit, BINARY, "");
	}

	@Deprecated
	public static RemoteCall<UserManagerment> deploy(Web3j web3j, TransactionManager transactionManager,
			BigInteger gasPrice, BigInteger gasLimit) {
		return deployRemoteCall(UserManagerment.class, web3j, transactionManager, gasPrice, gasLimit, BINARY, "");
	}
	
	/**************************************** 自定义的函数 ********************************************************/
	public RemoteCall<Bool> checkRegister(String userName) {
		final Function function = new Function(FUNC_CHECKREGISTER,
				Arrays.<Type>asList(new org.web3j.abi.datatypes.Utf8String(userName)),
				Arrays.<?>>asList(new TypeReference<Bool>() {
				}));
		return executeRemoteCallSingleValueReturn(function);
	}

	public RemoteCall<Bool> doLogin(String userName, String password) {
		final Function function = new Function(FUNC_DOLOGIN,
				Arrays.<Type>asList(new org.web3j.abi.datatypes.Utf8String(userName),
						new org.web3j.abi.datatypes.Utf8String(password)),
				Arrays.<?>>asList(new TypeReference<Bool>() {
				}));
		return executeRemoteCallSingleValueReturn(function);
	}

	public RemoteCall<List<Type>> getAllUserInfos(int index) {
		final Function function = new Function(FUNC_GETALLUSERINFOS,
				Arrays.<Type>asList(new org.web3j.abi.datatypes.generated.Uint256(index)),
				Arrays.<?>>asList(new TypeReference<Address>() {
				}, new TypeReference<Utf8String>() {
				}));
		return executeRemoteCallMultipleValueReturn(function);
	}

	public RemoteCall<Uint256> getTotalUserNum() {
		final Function function = new Function(FUNC_GETTOTALUSERNUM, Arrays.<Type>asList(),
				Arrays.<?>>asList(new TypeReference<Uint256>() {
				}));
		return executeRemoteCallSingleValueReturn(function);
	}

	public RemoteCall<List<Type>> getUserInfoByUserName(String userName) {
		final Function function = new Function(FUNC_GETUSERINFOBYUSERNAME,
				Arrays.<Type>asList(new org.web3j.abi.datatypes.Utf8String(userName)),
				Arrays.<?>>asList(new TypeReference<Address>() {
				}, new TypeReference<Utf8String>() {
				}));
		return executeRemoteCallMultipleValueReturn(function);
	}

	public RemoteCall<TransactionReceipt> register(String ethAddr, String userName, String password) {
		final Function function = new Function(FUNC_REGISTER,
				Arrays.<Type>asList(new org.web3j.abi.datatypes.Address(ethAddr),
						new org.web3j.abi.datatypes.Utf8String(userName),
						new org.web3j.abi.datatypes.Utf8String(password)),
				Collections.<?>>emptyList());
		return executeRemoteCallTransaction(function);
	}

	public RemoteCall<TransactionReceipt> updatePassword(String userName, String newPwd) {
		final Function function = new Function(FUNC_UPDATEPASSWORD,
				Arrays.<Type>asList(new org.web3j.abi.datatypes.Utf8String(userName),
						new org.web3j.abi.datatypes.Utf8String(newPwd)),
				Collections.<?>>emptyList());
		return executeRemoteCallTransaction(function);
	}
	/**************************************** END ********************************************************/
	
	@Deprecated
	public static UserManagerment load(String contractAddress, Web3j web3j, Credentials credentials,
			BigInteger gasPrice, BigInteger gasLimit) {
		return new UserManagerment(contractAddress, web3j, credentials, gasPrice, gasLimit);
	}

	@Deprecated
	public static UserManagerment load(String contractAddress, Web3j web3j, TransactionManager transactionManager,
			BigInteger gasPrice, BigInteger gasLimit) {
		return new UserManagerment(contractAddress, web3j, transactionManager, gasPrice, gasLimit);
	}

	public static UserManagerment load(String contractAddress, Web3j web3j, Credentials credentials,
			ContractGasProvider contractGasProvider) {
		return new UserManagerment(contractAddress, web3j, credentials, contractGasProvider);
	}

	public static UserManagerment load(String contractAddress, Web3j web3j, TransactionManager transactionManager,
			ContractGasProvider contractGasProvider) {
		return new UserManagerment(contractAddress, web3j, transactionManager, contractGasProvider);
	}
}

部署和调用

启动私链

（不再介绍，看之前记录）

部署合约

Consts.java

public class Consts {
	// GAS价格
	public static BigInteger GAS_PRICE = BigInteger.valueOf(2000_000_000L);
	// GAS上限
	public static BigInteger GAS_LIMIT = BigInteger.valueOf(4_300_000L);
	// 交易费用
	public static BigInteger GAS_VALUE = BigInteger.valueOf(100_000L);;
	// 账户密码
	public static String PASSWORD = "123";
	// 账户文件路径
	public static String PATH = "E:/BlockChain/node5/data/keystore/UTC--2020-04-11T07-54-54.678177700Z--12d4e53d6f017a2a62807876ec41fc97a0f60a71";
	// 合约地址，第一次部署之后记录下来
	public static String ADDRESS = "0x2e2d63186093b543d9f84a3f8343c59a3047718f";
	// chain id,在创世区块中定义的
	public static byte CHAINID = (byte) 666;
}

DeployedContract.java

public class DeployedContract {

	public static void main(String[] args) throws Exception {
		// 1. 默认连接到 http://localhost:8545/
		Web3j web3j = Web3j.build(new HttpService());
		// 2. 获取凭证
		Credentials credentials = WalletUtils.loadCredentials(Consts.PASSWORD, Consts.PATH);
		// 3.部署合约
		UserManagerment contract = UserManagerment.deploy(web3j, credentials, Consts.GAS_PRICE, Consts.GAS_LIMIT).send();
		// 4.获得合约地址
		System.out.println(contract.getContractAddress());
	}

}

调用合约

Main.java

public class Main {
	public static void main(String[] args) throws Exception {
		// 1.默认连接到 http://localhost:8545/
		Web3j web3j = Web3j.build(new HttpService());
		// 2.获取凭证
		Credentials credentials = WalletUtils.loadCredentials(Consts.PASSWORD, Consts.PATH);
		// 3.加载合约
		UserManagerment contract = UserManagerment.load(Consts.ADDRESS, web3j, credentials, Consts.GAS_PRICE,
				Consts.GAS_LIMIT);
		// 4.调用合约
		// 检查注册
		Boolean isRegister = contract.checkRegister("张三").send().getValue();
		System.out.println("用户名‘张三’是否被注册：" + isRegister);
		// 注册
		contract.register("0x2e2d63186093b543d9f84a3f8343c59a3047718f", "张三", "123").send();
		isRegister = contract.checkRegister("张三").send().getValue();
		System.out.println("用户名‘张三’是否被注册：" + isRegister);
		// 登录
		Boolean canLogin = contract.doLogin("张三", "123").send().getValue();
		if (canLogin) {
			System.out.println("登录成功");
		} else {
			System.out.println("登录失败");
		}
		// 获得用户信息
		System.out.println("张三信息如下：");
		List<Type> userInfo = contract.getUserInfoByUserName("张三").send();
		for (Type info : userInfo) {
			System.out.println(info.toString());
		}
		// 系统用户人数
		int userNum = contract.getTotalUserNum().send().getValue().intValue();
		System.out.println("总共的用户数：" + userNum);
		// 输出所有用户信息
		for (int i = 0; i < userNum; i++) {
			List<Type> user = contract.getAllUserInfos(i).send();
			for (Type info : user) {
				System.out.println(info.toString());
			}
		}
		// 5.关闭连接
		web3j.shutdown();
	}
}

运行结果：

最后

以上内容纯属学习记录！！！

附完整代码

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