update README.md (#24)

README.md

@@ -1,2 +1,84 @@
-# cryptology-java
-libsodium compatible SealedBox and SecretBox implementation in Java
+# CryptologyJava
+
+libsodium compatible CryptoSign, SealedBox and SecretBox implementation in Java.
+
+## Download
+
+Include in your project using Maven:
+
+```xml
+<dependency>
+    <groupId>io.xconn</groupId>
+    <artifactId>cryptology</artifactId>
+    <version>0.1.0</version>
+</dependency>
+```
+
+Or with Gradle:
+
+```groovy
+implementation 'io.xconn:cryptology:0.1.0'
+```
+
+## Usage
+
+### CryptoSign
+
+Generate ED25519 KeyPair
+
+```java
+KeyPair keyPair = CryptoSign.generateKeyPair();
+```
+
+Get PublicKey from PrivateKey
+
+```java
+byte[] privateKey = // ED25519 private key bytes
+byte[] publicKey = CryptoSign.getPublicKey(privateKey);
+```
+
+Sign Message
+
+```java
+byte[] privateKey = // ED25519 private key bytes
+byte[] message = "Hello, world!".getBytes();
+byte[] signature = CryptoSign.sign(privateKey, message);
+```
+
+### SealedBox
+
+Seal Message
+
+```java
+byte[] recipientPublicKey = // X25519 recipient's public key bytes
+byte[] message = "Secret message".getBytes();
+byte[] encryptedMessage = SealedBox.seal(message, recipientPublicKey);
+```
+
+Open Sealed Message
+
+```java
+byte[] privateKey = // X25519 recipient's private key bytes
+byte[] sealedMessage = // Sealed message bytes
+byte[] decryptedMessage = SealedBox.sealOpen(sealedMessage, privateKey);
+```
+
+### SecretBox
+
+Encrypt Message
+
+```java
+byte[] nonce = SecretBox.generateNonce();
+byte[] secretKey = SecretBox.generateSecret();
+byte[] message = "Secret message".getBytes();
+byte[] encryptedMessage = SecretBox.box(nonce, message, secretKey);
+```
+
+Decrypt Message
+
+```java
+byte[] nonce = // Nonce bytes
+byte[] secretKey = // Secret key bytes
+byte[] sealedMessage = // Sealed message bytes
+byte[] decryptedMessage = SecretBox.boxOpen(sealedMessage, nonce, secretKey);
+```