From a60fe48720b967a93c821e4f7865d731a2400937 Mon Sep 17 00:00:00 2001
From: jamesm <jamesm@lmax.com>
Date: Tue, 29 Oct 2024 17:09:57 -0400
Subject: [PATCH] Sha256 can just be a helper method on
 SolanaProgramDerivedAddress - it doesn't need to be it's own class

---
 .../encoding/SolanaProgramDerivedAddress.java | 19 ++++++++-
 .../java/com/lmax/solana4j/util/Sha256.java   | 40 -------------------
 .../com/lmax/solana4j/util/Sha256Test.java    | 25 ------------
 3 files changed, 17 insertions(+), 67 deletions(-)
 delete mode 100644 message-encoding/src/main/java/com/lmax/solana4j/util/Sha256.java
 delete mode 100644 message-encoding/src/test/java/com/lmax/solana4j/util/Sha256Test.java

diff --git a/message-encoding/src/main/java/com/lmax/solana4j/encoding/SolanaProgramDerivedAddress.java b/message-encoding/src/main/java/com/lmax/solana4j/encoding/SolanaProgramDerivedAddress.java
index 2cf1ec2c..0b427012 100644
--- a/message-encoding/src/main/java/com/lmax/solana4j/encoding/SolanaProgramDerivedAddress.java
+++ b/message-encoding/src/main/java/com/lmax/solana4j/encoding/SolanaProgramDerivedAddress.java
@@ -3,10 +3,11 @@
 import com.lmax.solana4j.api.ProgramDerivedAddress;
 import com.lmax.solana4j.api.PublicKey;
 import com.lmax.solana4j.util.Ed25519;
-import com.lmax.solana4j.util.Sha256;
 
 import java.nio.ByteBuffer;
 import java.nio.charset.StandardCharsets;
+import java.security.MessageDigest;
+import java.security.NoSuchAlgorithmException;
 import java.util.List;
 import java.util.Objects;
 
@@ -37,7 +38,7 @@ static ProgramDerivedAddress deriveProgramAddress(final List<byte[]> seeds, fina
             programId.write(seedsBuffer);
             seedsBuffer.put(PROGRAM_DERIVED_ADDRESS_BYTES);
 
-            final byte[] programAddress = Sha256.hash(seedsBuffer.array());
+            final byte[] programAddress = hash(seedsBuffer.array());
 
             if (isOffCurve(programAddress))
             {
@@ -48,6 +49,20 @@ static ProgramDerivedAddress deriveProgramAddress(final List<byte[]> seeds, fina
         throw new RuntimeException("Could not find a program address off the curve.");
     }
 
+    private static byte[] hash(final byte[] input)
+    {
+        final MessageDigest digest;
+        try
+        {
+            digest = MessageDigest.getInstance("SHA-256");
+        }
+        catch (final NoSuchAlgorithmException e)
+        {
+            throw new RuntimeException(e);
+        }
+        return digest.digest(input);
+    }
+
     private static boolean isOffCurve(final byte[] programAddress)
     {
         try
diff --git a/message-encoding/src/main/java/com/lmax/solana4j/util/Sha256.java b/message-encoding/src/main/java/com/lmax/solana4j/util/Sha256.java
deleted file mode 100644
index 3642ecb4..00000000
--- a/message-encoding/src/main/java/com/lmax/solana4j/util/Sha256.java
+++ /dev/null
@@ -1,40 +0,0 @@
-package com.lmax.solana4j.util;
-
-import java.security.MessageDigest;
-import java.security.NoSuchAlgorithmException;
-
-/**
- * Utility class for generating SHA-256 hashes.
- * <p>
- * This class provides a method to generate a SHA-256 hash from a given byte array.
- * SHA-256 is a cryptographic hash function that produces a 256-bit (32-byte) hash value.
- * It's commonly used for data integrity and security purposes.
- * </p>
- */
-public final class Sha256
-{
-    private Sha256()
-    {
-    }
-
-    /**
-     * Computes the SHA-256 hash of the input byte array.
-     *
-     * @param input the byte array to be hashed
-     * @return a byte array containing the SHA-256 hash of the input
-     * @throws RuntimeException if the SHA-256 algorithm is not available
-     */
-    public static byte[] hash(final byte[] input)
-    {
-        final MessageDigest digest;
-        try
-        {
-            digest = MessageDigest.getInstance("SHA-256");
-        }
-        catch (final NoSuchAlgorithmException e)
-        {
-            throw new RuntimeException(e);
-        }
-        return digest.digest(input);
-    }
-}
diff --git a/message-encoding/src/test/java/com/lmax/solana4j/util/Sha256Test.java b/message-encoding/src/test/java/com/lmax/solana4j/util/Sha256Test.java
deleted file mode 100644
index 4150b319..00000000
--- a/message-encoding/src/test/java/com/lmax/solana4j/util/Sha256Test.java
+++ /dev/null
@@ -1,25 +0,0 @@
-package com.lmax.solana4j.util;
-
-import org.junit.jupiter.api.Test;
-
-import static org.assertj.core.api.Assertions.assertThat;
-
-class Sha256Test
-{
-    @Test
-    void shouldHashToExpectedValue()
-    {
-        final var sample = new byte[]{10, 20, 30, 40, 50, 60, 70, 80, 90};
-        final var hashSample = new byte[]
-                {
-                -91, 31, -102, 11, 110, -93, 82, 58, -49, 70,
-                -105, -84, 116, -4, -114, 54, 83, -82, -116, -66,
-                 26, -65, 88, -83, -1, -80, 105, -31, -11, -24,
-                -62, -27
-                };
-
-        final byte[] hash = Sha256.hash(sample);
-
-        assertThat(hash).containsExactly(hashSample);
-    }
-}
\ No newline at end of file