Event support

abi-parser-simple/src/main/java/com/openelements/hiero/smartcontract/abi/simple/GsonAbiParser.java

@@ -18,7 +18,6 @@ public GsonAbiParser() {
         this.gson = new GsonBuilder()
                 .registerTypeAdapterFactory(new AbiTypeAdapterFactory())
                 .create();
-
     }
 
     public @NonNull AbiModel parse(@NonNull Reader abiReader) throws AbiParserException {

abi-parser-simple/src/main/java/com/openelements/hiero/smartcontract/abi/simple/implementation/AbiEntryTypeAdapter.java

@@ -12,6 +12,7 @@
 import java.util.ArrayList;
 import java.util.Collections;
 import java.util.List;
+import org.jspecify.annotations.NonNull;
 
 public class AbiEntryTypeAdapter extends BasicTypeAdapter<AbiEntry> {
 
@@ -20,7 +21,7 @@ public AbiEntryTypeAdapter(Gson gson) {
     }
 
     @Override
-    public AbiEntry read(JsonReader in) throws IOException {
+    public AbiEntry read(@NonNull final JsonReader in) throws IOException {
         final JsonObject abiEntryObject = readObject(in);
         final AbiEntryType type = getStringValue(abiEntryObject, "type")
                 .map(AbiEntryType::of)

abi-parser-simple/src/main/java/com/openelements/hiero/smartcontract/abi/simple/implementation/AbiModelTypeAdapter.java

@@ -18,7 +18,7 @@ public AbiModelTypeAdapter(@NonNull Gson gson) {
     }
 
     @Override
-    public AbiModel read(JsonReader in) throws IOException {
+    public AbiModel read(@NonNull final JsonReader in) throws IOException {
         JsonArray array = readArray(in);
         final List<AbiEntry> entries = new ArrayList<>();
         array.forEach(jsonElement -> {

abi-parser-simple/src/main/java/com/openelements/hiero/smartcontract/abi/simple/implementation/AbiParameterTypeAdapter.java

@@ -9,6 +9,7 @@
 import java.util.ArrayList;
 import java.util.Collections;
 import java.util.List;
+import org.jspecify.annotations.NonNull;
 
 public class AbiParameterTypeAdapter extends BasicTypeAdapter<AbiParameter> {
 
@@ -17,7 +18,7 @@ public AbiParameterTypeAdapter(Gson gson) {
     }
 
     @Override
-    public AbiParameter read(JsonReader in) throws IOException {
+    public AbiParameter read(@NonNull final JsonReader in) throws IOException {
         final JsonObject parameterObject = readObject(in);
 
         final String name = getStringValue(parameterObject, "name")

abi-parser-simple/src/main/java/com/openelements/hiero/smartcontract/abi/simple/implementation/AbiTypeAdapterFactory.java

@@ -7,11 +7,14 @@
 import com.openelements.hiero.smartcontract.abi.model.AbiEntry;
 import com.openelements.hiero.smartcontract.abi.model.AbiModel;
 import com.openelements.hiero.smartcontract.abi.model.AbiParameter;
+import java.util.Objects;
+import org.jspecify.annotations.NonNull;
 
 public class AbiTypeAdapterFactory implements TypeAdapterFactory {
 
     @Override
-    public <T> TypeAdapter<T> create(Gson gson, TypeToken<T> type) {
+    public <T> TypeAdapter<T> create(@NonNull final Gson gson, @NonNull final TypeToken<T> type) {
+        Objects.requireNonNull(type, "type must not be null");
         if (type.getRawType().equals(AbiModel.class)) {
             return (TypeAdapter<T>) new AbiModelTypeAdapter(gson);
         }

abi-parser-simple/src/main/java/com/openelements/hiero/smartcontract/abi/simple/implementation/BasicTypeAdapter.java

@@ -21,31 +21,30 @@ public abstract class BasicTypeAdapter<T> extends TypeAdapter<T> {
 
     private final TypeAdapter<JsonArray> arrayTypeAdapter;
 
-
-    public BasicTypeAdapter(final Gson gson) {
+    public BasicTypeAdapter(@NonNull final Gson gson) {
         this.gson = Objects.requireNonNull(gson, "gson");
         objectTypeAdapter = gson.getAdapter(JsonObject.class);
         arrayTypeAdapter = gson.getAdapter(JsonArray.class);
     }
 
-    protected JsonObject readObject(JsonReader in) throws IOException {
+    protected JsonObject readObject(@NonNull final JsonReader in) throws IOException {
         return objectTypeAdapter.read(in);
     }
 
-    protected JsonArray readArray(JsonReader in) throws IOException {
+    protected JsonArray readArray(@NonNull final JsonReader in) throws IOException {
         return arrayTypeAdapter.read(in);
     }
 
-
-    protected <T> T fromJson(JsonElement json, Class<T> classOfT) throws JsonSyntaxException {
+    protected <T> T fromJson(@NonNull final JsonElement json, @NonNull final Class<T> classOfT) throws JsonSyntaxException {
         return gson.fromJson(json, classOfT);
     }
 
-
+    @NonNull
     protected Gson getGson() {
         return gson;
     }
 
+    @NonNull
     protected TypeAdapter<JsonObject> getObjectTypeAdapter() {
         return objectTypeAdapter;
     }
@@ -55,6 +54,7 @@ public void write(JsonWriter out, T value) throws IOException {
         throw new UnsupportedOperationException("Not supported yet.");
     }
 
+    @NonNull
     protected JsonArray getArray(@NonNull final JsonObject jsonObject, @NonNull final String key) {
         Objects.requireNonNull(jsonObject, "jsonObject");
         Objects.requireNonNull(key, "key");
@@ -69,6 +69,7 @@ protected JsonArray getArray(@NonNull final JsonObject jsonObject, @NonNull fina
         return new JsonArray();
     }
 
+    @NonNull
     protected Optional<String> getStringValue(@NonNull final JsonObject jsonObject, @NonNull final String key) {
         Objects.requireNonNull(jsonObject, "jsonObject");
         Objects.requireNonNull(key, "key");
@@ -82,6 +83,7 @@ protected Optional<String> getStringValue(@NonNull final JsonObject jsonObject,
         return Optional.empty();
     }
 
+    @NonNull
     protected Optional<Boolean> getBooleanValue(@NonNull final JsonObject jsonObject, @NonNull final String key) {
         Objects.requireNonNull(jsonObject, "jsonObject");
         Objects.requireNonNull(key, "key");

abi-parser/pom.xml

@@ -23,6 +23,15 @@
       <artifactId>jspecify</artifactId>
       <scope>compile</scope>
     </dependency>
+    <dependency>
+      <groupId>org.bouncycastle</groupId>
+      <artifactId>bcprov-jdk15to18</artifactId>
+    </dependency>
+    <dependency>
+      <groupId>org.junit.jupiter</groupId>
+      <artifactId>junit-jupiter</artifactId>
+      <scope>test</scope>
+    </dependency>
   </dependencies>
 
   <build>

abi-parser/src/main/java/com/openelements/hiero/smartcontract/abi/model/AbiEvent.java

@@ -1,9 +1,11 @@
 package com.openelements.hiero.smartcontract.abi.model;
 
+import com.openelements.hiero.smartcontract.abi.util.HexConverter;
+import com.openelements.hiero.smartcontract.abi.util.KeccakUtil;
+import java.nio.charset.StandardCharsets;
 import java.util.List;
 import java.util.Objects;
 import org.jspecify.annotations.NonNull;
-import org.jspecify.annotations.Nullable;
 
 public record AbiEvent(@NonNull String name, @NonNull List<AbiParameter> inputs, boolean anonymous) implements AbiEntry{
 
@@ -16,4 +18,32 @@ public record AbiEvent(@NonNull String name, @NonNull List<AbiParameter> inputs,
     public AbiEntryType type() {
         return AbiEntryType.EVENT;
     }
+
+    @NonNull
+    public List<AbiParameter> getIndexedInputParameters() {
+        return inputs.stream().filter(AbiParameter::indexed).toList();
+    }
+
+    @NonNull
+    public List<AbiParameter> getNonIndexedInputParameters() {
+        return inputs.stream().filter(parameter -> !parameter.indexed()).toList();
+    }
+
+    @NonNull
+    private String createEventSignature() {
+        final List<String> canonicalParameterTypes = inputs.stream().map(AbiParameter::getCanonicalType).toList();
+        return name + "(" + String.join(",", canonicalParameterTypes) + ")";
+    }
+
+    @NonNull
+    private byte[] createEventSignatureHash() {
+        final String eventSignature = createEventSignature();
+        return KeccakUtil.keccak256(eventSignature.getBytes(StandardCharsets.UTF_8));
+    }
+
+    @NonNull
+    public String createEventSignatureHashAsHex() {
+        final byte[] eventSignatureHash = createEventSignatureHash();
+        return "0x" + HexConverter.bytesToHex(eventSignatureHash);
+    }
 }

abi-parser/src/main/java/com/openelements/hiero/smartcontract/abi/model/AbiFunction.java

@@ -36,6 +36,5 @@ public record AbiFunction(@NonNull AbiEntryType type, @Nullable String name, @No
         Objects.requireNonNull(inputs, "inputs");
         Objects.requireNonNull(outputs, "outputs");
         Objects.requireNonNull(stateMutability, "stateMutability");
-
     }
 }

abi-parser/src/main/java/com/openelements/hiero/smartcontract/abi/model/AbiModel.java

@@ -10,19 +10,24 @@ public record AbiModel(@NonNull List<AbiEntry> entries) {
         Objects.requireNonNull(entries, "entries");
     }
 
+    @NonNull
     public List<AbiFunction> getFunctions() {
         return getEntriesOfType(AbiFunction.class);
     }
 
+    @NonNull
     public List<AbiEvent> getEvents() {
         return getEntriesOfType(AbiEvent.class);
     }
 
+    @NonNull
     public List<AbiError> getErrors() {
         return getEntriesOfType(AbiError.class);
     }
 
-    private <T extends AbiEntry> List<T> getEntriesOfType(Class<T> type) {
+    @NonNull
+    private <T extends AbiEntry> List<T> getEntriesOfType(@NonNull final Class<T> type) {
+        Objects.requireNonNull(type, "type must not be null");
         return entries.stream()
                 .filter(type::isInstance)
                 .map(type::cast)

abi-parser/src/main/java/com/openelements/hiero/smartcontract/abi/model/AbiParameter.java

@@ -18,4 +18,8 @@ public record AbiParameter(@NonNull String name, @NonNull AbiParameterType type,
         }
     }
 
+    public String getCanonicalType() {
+        return type.getCanonicalType();
+    }
+
 }

abi-parser/src/main/java/com/openelements/hiero/smartcontract/abi/model/AbiParameterType.java

@@ -6,6 +6,7 @@ public enum AbiParameterType {
     BYTE32,
     BOOL,
     UINT256,
+    UINT,
     TUPLE;
 
     public static AbiParameterType of(final String name) {
@@ -15,7 +16,39 @@ public static AbiParameterType of(final String name) {
             case "bytes32" -> BYTE32;
             case "bool" -> BOOL;
             case "uint256" -> UINT256;
+            case "uint" -> UINT;
+            case "tuple" -> TUPLE;
             default -> throw new IllegalArgumentException("Unknown value type: " + name);
         };
     }
+
+    public String getCanonicalType() {
+        return switch (this) {
+            case ADDRESS -> "address";
+            case STRING -> "string";
+            case BYTE32 -> "bytes32";
+            case BOOL -> "bool";
+            case UINT256 -> "uint256";
+            case TUPLE -> "tuple";
+            case UINT -> "uint256";
+        };
+    }
+
+    public boolean isDynamic() {
+        return switch (this) {
+            case STRING, BYTE32 -> true;
+            default -> false;
+        };
+    }
+
+    public int getFixedSize() {
+        return switch (this) {
+            case ADDRESS -> 20;
+            case BOOL -> 1;
+            case UINT256 -> 32;
+            case UINT -> 32;
+            case BYTE32 -> 32;
+            default -> throw new IllegalStateException("No fixed size for type: " + this);
+        };
+    }
 }

abi-parser/src/main/java/com/openelements/hiero/smartcontract/abi/util/HexConverter.java

@@ -0,0 +1,35 @@
+package com.openelements.hiero.smartcontract.abi.util;
+
+import java.nio.charset.StandardCharsets;
+import java.util.Objects;
+import org.jspecify.annotations.NonNull;
+
+public class HexConverter {
+
+    private static final byte[] HEX_ARRAY = "0123456789ABCDEF".getBytes(StandardCharsets.US_ASCII);
+
+    @NonNull
+    public static String bytesToHex(@NonNull final byte[] bytes) {
+        //see https://stackoverflow.com/questions/9655181/java-convert-a-byte-array-to-a-hex-string
+        Objects.requireNonNull(bytes, "bytes must not be null");
+        final byte[] hexChars = new byte[bytes.length * 2];
+        for (int j = 0; j < bytes.length; j++) {
+            int v = bytes[j] & 0xFF;
+            hexChars[j * 2] = HEX_ARRAY[v >>> 4];
+            hexChars[j * 2 + 1] = HEX_ARRAY[v & 0x0F];
+        }
+        return new String(hexChars, StandardCharsets.UTF_8).toLowerCase();
+    }
+
+    @NonNull
+    public static byte[] hexToBytes(@NonNull final String hex) {
+        Objects.requireNonNull(hex, "hex must not be null");
+        int len = hex.length();
+        byte[] data = new byte[len / 2];
+        for (int i = 0; i < len; i += 2) {
+            data[i / 2] = (byte) ((Character.digit(hex.charAt(i), 16) << 4)
+                    + Character.digit(hex.charAt(i+1), 16));
+        }
+        return data;
+    }
+}

abi-parser/src/main/java/com/openelements/hiero/smartcontract/abi/util/KeccakUtil.java

@@ -0,0 +1,13 @@
+package com.openelements.hiero.smartcontract.abi.util;
+
+import org.bouncycastle.jcajce.provider.digest.Keccak;
+import org.jspecify.annotations.NonNull;
+
+public class KeccakUtil {
+
+    public static byte[] keccak256(@NonNull final byte[] data) {
+        final Keccak.DigestKeccak kecc = new Keccak.Digest256();
+        kecc.update(data);
+        return kecc.digest();
+    }
+}

abi-parser/src/main/java/module-info.java

@@ -1,5 +1,7 @@
 module com.openelements.hiero.smartcontract.abi {
     exports com.openelements.hiero.smartcontract.abi;
     exports com.openelements.hiero.smartcontract.abi.model;
+    exports com.openelements.hiero.smartcontract.abi.util;
     requires org.jspecify;
+    requires org.bouncycastle.provider;
 }

abi-parser/src/test/java/com/openelements/hiero/smartcontract/abi/test/AbiEventTests.java

@@ -0,0 +1,44 @@
+package com.openelements.hiero.smartcontract.abi.test;
+
+import com.openelements.hiero.smartcontract.abi.model.AbiEvent;
+import com.openelements.hiero.smartcontract.abi.model.AbiParameter;
+import com.openelements.hiero.smartcontract.abi.model.AbiParameterType;
+import java.util.List;
+import org.junit.jupiter.api.Assertions;
+import org.junit.jupiter.api.Test;
+
+public class AbiEventTests {
+
+    @Test
+    void testEventSignatureCreation() {
+        // Given
+        final List<AbiParameter> inputs = List.of(
+                new AbiParameter("identifier_", AbiParameterType.STRING, List.of(), false)
+        );
+        final AbiEvent event = new AbiEvent("HashAdded", inputs, false);
+
+
+        // When
+        String hex = event.createEventSignatureHashAsHex();
+
+        // Then
+        Assertions.assertEquals("0xe0c9f5e6f5abddac86dac0e02afc9f3fda7b7fc6d9454a13c51fcb28621e1e5f", hex);
+    }
+
+    @Test
+    void testEventSignatureCreation2() {
+        // Given
+        final List<AbiParameter> inputs = List.of(
+                new AbiParameter("count", AbiParameterType.UINT, List.of(), false)
+        );
+        final AbiEvent event = new AbiEvent("MissingVerificationCountUpdated", inputs, false);
+
+
+        // When
+        String hex = event.createEventSignatureHashAsHex();
+
+        // Then
+        Assertions.assertEquals("0x271219bdbb9b91472a5df68ef7a9d3f8de02f3c27b93a35306f888acf081ea60", hex);
+    }
+
+}