java licence限制

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mob64ca12e5502a 2024-06-24 06:43:34 ©著作权

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实现Java Licence 限制教程

1. 流程步骤:

步骤	操作
1	生成密钥对
2	生成许可证
3	验证许可证

2. 生成密钥对

在Java中生成密钥对的方式是使用KeyPairGenerator类，下面是代码示例：

// 生成RSA密钥对
KeyPairGenerator keyGen = KeyPairGenerator.getInstance("RSA");
keyGen.initialize(1024);
KeyPair keyPair = keyGen.generateKeyPair();

// 获取公钥和私钥
PublicKey publicKey = keyPair.getPublic();
PrivateKey privateKey = keyPair.getPrivate();

3. 生成许可证

生成许可证的过程需要将许可证信息进行签名，下面是代码示例：

// 加载私钥
byte[] privateKeyBytes = Files.readAllBytes(Paths.get("privateKey.txt"));
PKCS8EncodedKeySpec privateKeySpec = new PKCS8EncodedKeySpec(privateKeyBytes);
KeyFactory keyFactory = KeyFactory.getInstance("RSA");
PrivateKey privateKey = keyFactory.generatePrivate(privateKeySpec);

// 生成许可证信息
String licenseInfo = "Valid until 2022-12-31";

// 签名许可证信息
Signature signature = Signature.getInstance("SHA256withRSA");
signature.initSign(privateKey);
signature.update(licenseInfo.getBytes());
byte[] signatureBytes = signature.sign();

// 将许可证信息和签名保存到文件
String license = licenseInfo + "#" + Base64.getEncoder().encodeToString(signatureBytes);
Files.write(Paths.get("license.txt"), license.getBytes());

4. 验证许可证

验证许可证的过程需要将许可证信息和签名进行验签，下面是代码示例：

// 加载公钥
byte[] publicKeyBytes = Files.readAllBytes(Paths.get("publicKey.txt"));
X509EncodedKeySpec publicKeySpec = new X509EncodedKeySpec(publicKeyBytes);
PublicKey publicKey = keyFactory.generatePublic(publicKeySpec);

// 读取许可证文件
String license = new String(Files.readAllBytes(Paths.get("license.txt")));
String[] parts = license.split("#");
String licenseInfo = parts[0];
byte[] signatureBytes = Base64.getDecoder().decode(parts[1]);

// 验证许可证信息
Signature signature = Signature.getInstance("SHA256withRSA");
signature.initVerify(publicKey);
signature.update(licenseInfo.getBytes());
boolean verified = signature.verify(signatureBytes);

if (verified) {
    System.out.println("License is valid.");
} else {
    System.out.println("License is invalid.");
}