国密算法（SM2-SM3）Java 使用 demo maven 工程

很高兴回答你的问题！以下是一个使用国密算法（SM2-SM3）的Java Demo Maven工程，供您参考：

1. 首先，在pom.xml文件中添加以下依赖：

<dependency>
    <groupId>com.huawei.security</groupId>
    <artifactId>sm</artifactId>
    <version>2.0.5.300</version>
</dependency>

2. 创建SM2密钥对

import com.huawei.security.sm.SM2KeyPair;
import com.huawei.security.sm.SM2PrivateKey;
import com.huawei.security.sm.SM2PublicKey;
import java.security.NoSuchAlgorithmException;
import java.security.NoSuchProviderException;
import java.security.Security;

public class SM2Demo {
    public static void main(String[] args) throws NoSuchProviderException, NoSuchAlgorithmException {
        Security.addProvider(new org.bouncycastle.jce.provider.BouncyCastleProvider());

        SM2KeyPair sm2KeyPair = new SM2KeyPair();
        SM2PublicKey publicKey = sm2KeyPair.getPublicKey();
        SM2PrivateKey privateKey = sm2KeyPair.getPrivateKey();

        System.out.println("publicKey: " + publicKey.getHexString());
        System.out.println("privateKey: " + privateKey.getHexString());
    }
}

3. SM2加密和解密

import com.huawei.security.sm.SM2PrivateKey;
import com.huawei.security.sm.SM2PublicKey;
import com.huawei.security.sm.SM2Engine;
import java.security.NoSuchAlgorithmException;
import java.security.NoSuchProviderException;
import java.security.Security;
import java.security.InvalidAlgorithmParameterException;
import java.security.InvalidKeyException;
import java.security.KeyPairGenerator;
import javax.crypto.Cipher;
import javax.crypto.NoSuchPaddingException;

public class SM2Demo {
    public static void main(String[] args) throws NoSuchProviderException, NoSuchAlgorithmException, InvalidAlgorithmParameterException, InvalidKeyException, NoSuchPaddingException {
        Security.addProvider(new org.bouncycastle.jce.provider.BouncyCastleProvider());

        // 创建密钥对
        KeyPairGenerator keyPairGenerator = KeyPairGenerator.getInstance("EC", "BC");
        keyPairGenerator.initialize(256);
        SM2KeyPair sm2KeyPair = new SM2KeyPair(keyPairGenerator.generateKeyPair());

        // 获取公钥和私钥
        SM2PublicKey publicKey = sm2KeyPair.getPublicKey();
        SM2PrivateKey privateKey = sm2KeyPair.getPrivateKey();

        // 加密
        SM2Engine sm2Engine = new SM2Engine();
        Cipher cipher = Cipher.getInstance(sm2Engine.getAlgorithmName(), "BC");
        cipher.init(Cipher.ENCRYPT_MODE, publicKey);
        byte[] plaintext = "Hello, world!".getBytes();
        byte[] ciphertext = cipher.doFinal(plaintext);
        System.out.println("ciphertext: " + new String(ciphertext));

        // 解密
        cipher.init(Cipher.DECRYPT_MODE, privateKey);
        byte[] decrypted = cipher.doFinal(ciphertext);
        System.out.println("decrypted: " + new String(decrypted));
    }
}

4. SM3哈希算法

import com.huawei.security.sm.SM3Digest;
import java.security.NoSuchAlgorithmException;
import java.security.NoSuchProviderException;
import java.security.Security;

public class SM3Demo {
    public static void main(String[] args) throws NoSuchProviderException, NoSuchAlgorithmException {
        Security.addProvider(new org.bouncycastle.jce.provider.BouncyCastleProvider());

        // 计算哈希值
        SM3Digest sm3Digest = new SM3Digest();
        byte[] plaintext = "Hello, world!".getBytes();
        sm3Digest.update(plaintext, 0, plaintext.length);
        byte[] hash = new byte[sm3Digest.getDigestSize()];
        sm3Digest.doFinal(hash, 0);
        System.out.println("hash: " + org.bouncycastle.util.encoders.Hex.toHexString(hash));
    }
}

希望这个Demo工程能够帮助您使用国密算法（SM2-SM3）的Java开发。如果您有任何疑问，请随时联系我！