[#1] code cleanup

update README.md
Signed-off-by: Ori Bruk <o.bruk@yadro.com>

README.md

@@ -21,18 +21,18 @@ neo-go wallet export -w <path_to_your_wallet> -d <address_from_p1>
 ### Container
 
 ```java
-import info.FrostFS.sdk.enums.BasicAcl;
 import info.FrostFS.sdk.dto.container.Container;
 import info.FrostFS.sdk.dto.netmap.PlacementPolicy;
 import info.FrostFS.sdk.dto.netmap.Replica;
+import info.FrostFS.sdk.enums.BasicAcl;
+import info.FrostFS.sdk.jdo.ClientSettings;
 import info.FrostFS.sdk.services.FrostFSClient;
 
 public class ContainerExample {
 
     public void example() {
-        Client client = new Client( < your_key >);
+        ClientSettings clientSettings = new ClientSettings(<your_key>, <your_host>);
-        GrpcClient grpcClient = new GrpcClient( < your_host >);
+        FrostFSClient frostFSClient = new FrostFSClient(clientSettings);
-        FrostFSClient frostFSClient = new FrostFSClient(grpcClient, client);
 
         // Create container
         var placementPolicy = new PlacementPolicy(true, new Replica[]{new Replica(1)});
@@ -58,6 +58,7 @@ import info.FrostFS.sdk.dto.container.ContainerId;
 import info.FrostFS.sdk.dto.object.ObjectAttribute;
 import info.FrostFS.sdk.dto.object.ObjectFilter;
 import info.FrostFS.sdk.dto.object.ObjectHeader;
+import info.FrostFS.sdk.jdo.PutObjectParameters;
 import info.FrostFS.sdk.services.FrostFSClient;
 
 import java.io.FileInputStream;
@@ -66,9 +67,8 @@ import java.io.IOException;
 public class ObjectExample {
 
     public void example() {
-        Client client = new Client( < your_key >);
+        ClientSettings clientSettings = new ClientSettings(<your_key>, <your_host>);
-        GrpcClient grpcClient = new GrpcClient( < your_host >);
+        FrostFSClient frostFSClient = new FrostFSClient(clientSettings);
-        FrostFSClient frostFSClient = new FrostFSClient(grpcClient, client);
 
         // Put object
         info.FrostFS.sdk.dto.object.ObjectId objectId;
@@ -76,7 +76,9 @@ public class ObjectExample {
             var cat = new ObjectHeader(
                     containerId, ObjectType.REGULAR, new ObjectAttribute[]{new ObjectAttribute("Filename", "cat.jpg")}
             );
-            objectId = frostFSClient.putObject(cat, fis);
+
+            var params = new PutObjectParameters(cat, fis);
+            objectId = frostFSClient.putObject(params);
         } catch (IOException e) {
             throw new RuntimeException(e);
         }

client/src/main/java/info/FrostFS/sdk/Main.java

@@ -1,67 +0,0 @@
-package info.FrostFS.sdk;
-
-import info.FrostFS.sdk.dto.container.Container;
-import info.FrostFS.sdk.dto.container.ContainerId;
-import info.FrostFS.sdk.enums.BasicAcl;
-import info.FrostFS.sdk.enums.ObjectType;
-import info.FrostFS.sdk.dto.netmap.PlacementPolicy;
-import info.FrostFS.sdk.dto.netmap.Replica;
-import info.FrostFS.sdk.dto.object.ObjectAttribute;
-import info.FrostFS.sdk.dto.object.ObjectFrostFS;
-import info.FrostFS.sdk.dto.object.ObjectHeader;
-import info.FrostFS.sdk.dto.object.ObjectId;
-import info.FrostFS.sdk.services.FrostFSClient;
-import info.FrostFS.sdk.tools.ClientSettings;
-import info.FrostFS.sdk.tools.PutObjectParameters;
-
-import java.io.FileInputStream;
-import java.io.FileNotFoundException;
-import java.util.Collections;
-import java.util.List;
-
-public class Main {
-    public static void main(String[] args) throws Exception {
-        ClientSettings clientSettings = new ClientSettings("KwHDAJ66o8FoLBjVbjP2sWBmgBMGjt7Vv4boA7xQrBoAYBE397Aq", "http://localhost:8080");
-        FrostFSClient frostFSClient = new FrostFSClient(clientSettings);
-/*
-        var res2 = frostFSClient.searchObjectsAsync(new ContainerId("EQGx2QeYHJb53uRwYGzcQaW191sZpdNrjutk6veUSV2R"));
-*/
-        var placementPolicy = new PlacementPolicy(true, new Replica[]{new Replica(1)});
-        var containerId = frostFSClient.createContainer(new Container(BasicAcl.PUBLIC_RW, placementPolicy));
-        Thread.sleep(1000);
-
-        FileInputStream file = null;
-        try {
-            file = new FileInputStream("/home/ori/Desktop/cat.jpg");
-            var cat = new ObjectHeader(containerId, ObjectType.REGULAR, Collections.singletonList(new ObjectAttribute("Filename", "cat3.jpg")));
-
-            var params = new PutObjectParameters(cat, file, false, 1024);
-            var tty = frostFSClient.putObject(params);
-
-            System.out.println(1);
-        } catch (FileNotFoundException e) {
-            throw new RuntimeException(e);
-        }
-
-
-        var res = frostFSClient.searchObjects(containerId);
-
-        ObjectFrostFS res3 = frostFSClient
-                .getObject(new ContainerId("EQGx2QeYHJb53uRwYGzcQaW191sZpdNrjutk6veUSV2R"), new ObjectId("85orCLKSu3X1jGiTFmwmTUsBU88RBARNwuRwrEy5pyww"));
-
-
-        var ttttt = frostFSClient.getNetworkSettings();
-        Container container2 = frostFSClient.getContainer(new ContainerId("EQGx2QeYHJb53uRwYGzcQaW191sZpdNrjutk6veUSV2R"));
-
-
-
-
-        Container container = frostFSClient.getContainer(containerId);
-        List<ContainerId> containerIds = frostFSClient.listContainers();
-/*
-        frostFSClient.deleteContainerAsync(containerId);
-*/
-        containerIds = frostFSClient.listContainers();
-        System.out.println();
-    }
-}

client/src/main/java/info/FrostFS/sdk/constants/CryptoConst.java

@@ -0,0 +1,5 @@
+package info.FrostFS.sdk.constants;
+
+public class CryptoConst {
+    public static final String SIGNATURE_ALGORITHM = "NONEwithECDSAinP1363Format";
+}

client/src/main/java/info/FrostFS/sdk/jdo/ClientEnvironment.java

@@ -1,4 +1,4 @@
-package info.FrostFS.sdk.tools;
+package info.FrostFS.sdk.jdo;
 
 import info.FrostFS.sdk.dto.OwnerId;
 import info.FrostFS.sdk.dto.Version;

client/src/main/java/info/FrostFS/sdk/jdo/ClientSettings.java

@@ -1,4 +1,4 @@
-package info.FrostFS.sdk.tools;
+package info.FrostFS.sdk.jdo;
 
 import io.grpc.ChannelCredentials;
 import org.apache.commons.lang3.StringUtils;

client/src/main/java/info/FrostFS/sdk/jdo/ECDsa.java

@@ -1,4 +1,4 @@
-package info.FrostFS.sdk.tools;
+package info.FrostFS.sdk.jdo;
 
 import java.security.PrivateKey;
 

client/src/main/java/info/FrostFS/sdk/jdo/NetworkSettings.java

@@ -1,4 +1,4 @@
-package info.FrostFS.sdk.tools;
+package info.FrostFS.sdk.jdo;
 
 import java.util.HashMap;
 import java.util.Map;

client/src/main/java/info/FrostFS/sdk/jdo/PutObjectParameters.java

@@ -1,4 +1,4 @@
-package info.FrostFS.sdk.tools;
+package info.FrostFS.sdk.jdo;
 
 import info.FrostFS.sdk.dto.object.ObjectHeader;
 

client/src/main/java/info/FrostFS/sdk/services/ContextAccessor.java

@@ -1,6 +1,6 @@
 package info.FrostFS.sdk.services;
 
-import info.FrostFS.sdk.tools.ClientEnvironment;
+import info.FrostFS.sdk.jdo.ClientEnvironment;
 
 public class ContextAccessor {
     private final ClientEnvironment context;

client/src/main/java/info/FrostFS/sdk/services/FrostFSClient.java

@@ -1,29 +1,32 @@
 package info.FrostFS.sdk.services;
 
 import frostFS.session.Types;
-import info.FrostFS.sdk.tools.ClientSettings;
-import info.FrostFS.sdk.tools.PutObjectParameters;
-import info.FrostFS.sdk.dto.container.Container;
-import info.FrostFS.sdk.dto.container.ContainerId;
 import info.FrostFS.sdk.dto.SessionToken;
 import info.FrostFS.sdk.dto.Version;
+import info.FrostFS.sdk.dto.container.Container;
+import info.FrostFS.sdk.dto.container.ContainerId;
 import info.FrostFS.sdk.dto.netmap.NetmapSnapshot;
 import info.FrostFS.sdk.dto.netmap.NodeInfo;
 import info.FrostFS.sdk.dto.object.ObjectFilter;
 import info.FrostFS.sdk.dto.object.ObjectFrostFS;
 import info.FrostFS.sdk.dto.object.ObjectHeader;
 import info.FrostFS.sdk.dto.object.ObjectId;
+import info.FrostFS.sdk.jdo.ClientEnvironment;
+import info.FrostFS.sdk.jdo.ClientSettings;
+import info.FrostFS.sdk.jdo.NetworkSettings;
+import info.FrostFS.sdk.jdo.PutObjectParameters;
 import info.FrostFS.sdk.services.impl.*;
-import info.FrostFS.sdk.tools.ClientEnvironment;
-import info.FrostFS.sdk.tools.NetworkSettings;
 import io.grpc.Channel;
 
 import java.util.List;
 
-import static info.FrostFS.sdk.GrpcClient.initGrpcChannel;
+import static info.FrostFS.sdk.tools.GrpcClient.initGrpcChannel;
 import static java.util.Objects.isNull;
 
 public class FrostFSClient implements ContainerClient, ObjectClient, NetmapClient, SessionClient, ToolsClient {
+    private static final String ERROR_CLIENT_OPTIONS_INIT = "Options must be initialized.";
+    private static final String ERROR_VERSION_SUPPORT_TEMPLATE = "FrostFS %s is not supported.";
+
     private final ContainerService containerService;
     private final NetmapService netmapService;
     private final ObjectService objectService;
@@ -32,7 +35,7 @@ public class FrostFSClient implements ContainerClient, ObjectClient, NetmapClien
 
     public FrostFSClient(ClientSettings clientSettings) {
         if (isNull(clientSettings)) {
-            throw new IllegalArgumentException("Options must be initialized");
+            throw new IllegalArgumentException(ERROR_CLIENT_OPTIONS_INIT);
         }
 
         clientSettings.validate();
@@ -53,9 +56,9 @@ public class FrostFSClient implements ContainerClient, ObjectClient, NetmapClien
     private void checkFrostFsVersionSupport(Version version) {
         var localNodeInfo = netmapService.getLocalNodeInfo();
         if (!localNodeInfo.getVersion().isSupported(version)) {
-            var msg = String.format("FrostFS %s is not supported.", localNodeInfo.getVersion());
+            throw new IllegalArgumentException(
-            System.out.println(msg);
+                    String.format(ERROR_VERSION_SUPPORT_TEMPLATE, localNodeInfo.getVersion())
-            throw new IllegalArgumentException(msg);
+            );
         }
     }
 

client/src/main/java/info/FrostFS/sdk/services/NetmapClient.java

@@ -2,7 +2,7 @@ package info.FrostFS.sdk.services;
 
 import info.FrostFS.sdk.dto.netmap.NetmapSnapshot;
 import info.FrostFS.sdk.dto.netmap.NodeInfo;
-import info.FrostFS.sdk.tools.NetworkSettings;
+import info.FrostFS.sdk.jdo.NetworkSettings;
 
 public interface NetmapClient {
     NetmapSnapshot getNetmapSnapshot();

client/src/main/java/info/FrostFS/sdk/services/ObjectClient.java

@@ -1,11 +1,11 @@
 package info.FrostFS.sdk.services;
 
 import info.FrostFS.sdk.dto.container.ContainerId;
-import info.FrostFS.sdk.tools.PutObjectParameters;
 import info.FrostFS.sdk.dto.object.ObjectFilter;
 import info.FrostFS.sdk.dto.object.ObjectFrostFS;
 import info.FrostFS.sdk.dto.object.ObjectHeader;
 import info.FrostFS.sdk.dto.object.ObjectId;
+import info.FrostFS.sdk.jdo.PutObjectParameters;
 
 public interface ObjectClient {
     ObjectHeader getObjectHead(ContainerId containerId, ObjectId objectId);

client/src/main/java/info/FrostFS/sdk/services/impl/ContainerService.java

@@ -2,23 +2,23 @@ package info.FrostFS.sdk.services.impl;
 
 import frostFS.container.ContainerServiceGrpc;
 import frostFS.container.Service;
-import info.FrostFS.sdk.Verifier;
 import info.FrostFS.sdk.dto.container.Container;
 import info.FrostFS.sdk.dto.container.ContainerId;
-import info.FrostFS.sdk.mappers.container.ContainerIdMapper;
+import info.FrostFS.sdk.jdo.ClientEnvironment;
-import info.FrostFS.sdk.mappers.container.ContainerMapper;
 import info.FrostFS.sdk.mappers.OwnerIdMapper;
 import info.FrostFS.sdk.mappers.VersionMapper;
+import info.FrostFS.sdk.mappers.container.ContainerIdMapper;
+import info.FrostFS.sdk.mappers.container.ContainerMapper;
 import info.FrostFS.sdk.services.ContainerClient;
 import info.FrostFS.sdk.services.ContextAccessor;
-import info.FrostFS.sdk.tools.ClientEnvironment;
+import info.FrostFS.sdk.tools.Verifier;
 
 import java.util.List;
 import java.util.stream.Collectors;
 
-import static info.FrostFS.sdk.RequestConstructor.addMetaHeader;
+import static info.FrostFS.sdk.tools.RequestConstructor.addMetaHeader;
-import static info.FrostFS.sdk.RequestSigner.sign;
+import static info.FrostFS.sdk.tools.RequestSigner.sign;
-import static info.FrostFS.sdk.RequestSigner.signRFC6979;
+import static info.FrostFS.sdk.tools.RequestSigner.signRFC6979;
 
 public class ContainerService extends ContextAccessor implements ContainerClient {
     private final ContainerServiceGrpc.ContainerServiceBlockingStub serviceBlockingStub;

client/src/main/java/info/FrostFS/sdk/services/impl/NetmapService.java

@@ -3,20 +3,20 @@ package info.FrostFS.sdk.services.impl;
 import frostFS.netmap.NetmapServiceGrpc;
 import frostFS.netmap.Service;
 import frostFS.netmap.Types;
-import info.FrostFS.sdk.Verifier;
 import info.FrostFS.sdk.dto.netmap.NetmapSnapshot;
 import info.FrostFS.sdk.dto.netmap.NodeInfo;
+import info.FrostFS.sdk.jdo.ClientEnvironment;
+import info.FrostFS.sdk.jdo.NetworkSettings;
 import info.FrostFS.sdk.mappers.netmap.NetmapSnapshotMapper;
 import info.FrostFS.sdk.mappers.netmap.NodeInfoMapper;
 import info.FrostFS.sdk.services.ContextAccessor;
 import info.FrostFS.sdk.services.NetmapClient;
-import info.FrostFS.sdk.tools.ClientEnvironment;
+import info.FrostFS.sdk.tools.Verifier;
-import info.FrostFS.sdk.tools.NetworkSettings;
 
 import java.nio.charset.StandardCharsets;
 
-import static info.FrostFS.sdk.RequestConstructor.addMetaHeader;
+import static info.FrostFS.sdk.tools.RequestConstructor.addMetaHeader;
-import static info.FrostFS.sdk.RequestSigner.sign;
+import static info.FrostFS.sdk.tools.RequestSigner.sign;
 import static java.util.Objects.nonNull;
 
 public class NetmapService extends ContextAccessor implements NetmapClient {

client/src/main/java/info/FrostFS/sdk/services/impl/ObjectReader.java

@@ -2,11 +2,14 @@ package info.FrostFS.sdk.services.impl;
 
 import frostFS.object.Service;
 import frostFS.object.Types;
-import info.FrostFS.sdk.Verifier;
+import info.FrostFS.sdk.tools.Verifier;
 
 import java.util.Iterator;
 
 public class ObjectReader {
+    public static final String ERROR_UNEXPECTED_STREAM = "unexpected end of stream";
+    public static final String ERROR_UNEXPECTED_MESSAGE_TYPE = "unexpected message type";
+
     public Iterator<Service.GetResponse> call;
 
     public ObjectReader(Iterator<Service.GetResponse> call) {
@@ -15,14 +18,14 @@ public class ObjectReader {
 
     public Types.Object readHeader() {
         if (!call.hasNext()) {
-            throw new IllegalArgumentException("unexpected end of stream");
+            throw new IllegalArgumentException(ERROR_UNEXPECTED_STREAM);
         }
 
         var response = call.next();
         Verifier.checkResponse(response);
 
         if (response.getBody().getObjectPartCase().getNumber() != Service.GetResponse.Body.INIT_FIELD_NUMBER) {
-            throw new IllegalArgumentException("unexpected message type");
+            throw new IllegalArgumentException(ERROR_UNEXPECTED_MESSAGE_TYPE);
         }
 
         return Types.Object.newBuilder()
@@ -40,7 +43,7 @@ public class ObjectReader {
         Verifier.checkResponse(response);
 
         if (response.getBody().getObjectPartCase().getNumber() != Service.GetResponse.Body.CHUNK_FIELD_NUMBER) {
-            throw new IllegalArgumentException("unexpected message type");
+            throw new IllegalArgumentException(ERROR_UNEXPECTED_MESSAGE_TYPE);
         }
 
         return response.getBody().getChunk().toByteArray();

client/src/main/java/info/FrostFS/sdk/services/impl/ObjectService.java

@@ -5,21 +5,22 @@ import com.google.protobuf.ByteString;
 import frostFS.object.ObjectServiceGrpc;
 import frostFS.object.Service;
 import frostFS.refs.Types;
-import info.FrostFS.sdk.Verifier;
 import info.FrostFS.sdk.constants.AppConst;
-import info.FrostFS.sdk.dto.container.ContainerId;
 import info.FrostFS.sdk.dto.Split;
+import info.FrostFS.sdk.dto.container.ContainerId;
 import info.FrostFS.sdk.dto.object.*;
-import info.FrostFS.sdk.mappers.*;
+import info.FrostFS.sdk.jdo.ClientEnvironment;
+import info.FrostFS.sdk.jdo.PutObjectParameters;
+import info.FrostFS.sdk.mappers.OwnerIdMapper;
+import info.FrostFS.sdk.mappers.VersionMapper;
 import info.FrostFS.sdk.mappers.container.ContainerIdMapper;
 import info.FrostFS.sdk.mappers.object.ObjectFilterMapper;
+import info.FrostFS.sdk.mappers.object.ObjectFrostFSMapper;
 import info.FrostFS.sdk.mappers.object.ObjectHeaderMapper;
 import info.FrostFS.sdk.mappers.object.ObjectIdMapper;
-import info.FrostFS.sdk.mappers.object.ObjectFrostFSMapper;
 import info.FrostFS.sdk.services.ContextAccessor;
 import info.FrostFS.sdk.services.ObjectClient;
-import info.FrostFS.sdk.tools.ClientEnvironment;
+import info.FrostFS.sdk.tools.Verifier;
-import info.FrostFS.sdk.tools.PutObjectParameters;
 import org.apache.commons.collections4.CollectionUtils;
 
 import java.io.FileInputStream;
@@ -29,12 +30,14 @@ import java.util.Arrays;
 import java.util.List;
 
 import static info.FrostFS.sdk.Helper.getSha256;
-import static info.FrostFS.sdk.RequestConstructor.addMetaHeader;
+import static info.FrostFS.sdk.tools.RequestConstructor.addMetaHeader;
-import static info.FrostFS.sdk.RequestConstructor.addObjectSessionToken;
+import static info.FrostFS.sdk.tools.RequestConstructor.addObjectSessionToken;
-import static info.FrostFS.sdk.RequestSigner.sign;
+import static info.FrostFS.sdk.tools.RequestSigner.sign;
 import static java.util.Objects.nonNull;
 
 public class ObjectService extends ContextAccessor implements ObjectClient {
+    private static final String ERROR_PAYLOAD = "PayloadLength must be specified";
+
     private final ObjectServiceGrpc.ObjectServiceBlockingStub objectServiceBlockingClient;
     private final ObjectServiceGrpc.ObjectServiceStub objectServiceClient;
     private final ObjectTools objectTools;
@@ -257,7 +260,7 @@ public class ObjectService extends ContextAccessor implements ObjectClient {
         var objectSize = (int) Math.min(payloadSize, networkSettings.getMaxObjectSize());
         var fullLength = header.getPayloadLength() == 0 ? payloadSize : header.getPayloadLength();
         if (fullLength == 0) {
-            throw new IllegalArgumentException("Payload stream must be able to seek or PayloadLength must be specified");
+            throw new IllegalArgumentException(ERROR_PAYLOAD);
         }
 
         var buffer = new byte[objectSize];

client/src/main/java/info/FrostFS/sdk/services/impl/ObjectTools.java

@@ -5,17 +5,17 @@ import frostFS.object.Types;
 import info.FrostFS.sdk.dto.object.ObjectFrostFS;
 import info.FrostFS.sdk.dto.object.ObjectHeader;
 import info.FrostFS.sdk.dto.object.ObjectId;
-import info.FrostFS.sdk.mappers.object.ObjectHeaderMapper;
+import info.FrostFS.sdk.jdo.ClientEnvironment;
-import info.FrostFS.sdk.mappers.object.ObjectIdMapper;
 import info.FrostFS.sdk.mappers.OwnerIdMapper;
 import info.FrostFS.sdk.mappers.VersionMapper;
+import info.FrostFS.sdk.mappers.object.ObjectHeaderMapper;
+import info.FrostFS.sdk.mappers.object.ObjectIdMapper;
 import info.FrostFS.sdk.services.ContextAccessor;
 import info.FrostFS.sdk.services.ToolsClient;
-import info.FrostFS.sdk.tools.ClientEnvironment;
 import org.apache.commons.collections4.ListUtils;
 
 import static info.FrostFS.sdk.Helper.getSha256;
-import static info.FrostFS.sdk.RequestSigner.signData;
+import static info.FrostFS.sdk.tools.RequestSigner.signData;
 import static java.util.Objects.nonNull;
 
 public class ObjectTools extends ContextAccessor implements ToolsClient {

client/src/main/java/info/FrostFS/sdk/services/impl/SearchReader.java

@@ -1,7 +1,7 @@
 package info.FrostFS.sdk.services.impl;
 
 import frostFS.object.Service;
-import info.FrostFS.sdk.Verifier;
+import info.FrostFS.sdk.tools.Verifier;
 
 import java.util.Iterator;
 import java.util.List;

client/src/main/java/info/FrostFS/sdk/services/impl/SessionService.java

@@ -4,14 +4,14 @@ import frostFS.session.Service;
 import frostFS.session.SessionServiceGrpc;
 import frostFS.session.Types;
 import info.FrostFS.sdk.dto.SessionToken;
+import info.FrostFS.sdk.jdo.ClientEnvironment;
 import info.FrostFS.sdk.mappers.OwnerIdMapper;
 import info.FrostFS.sdk.mappers.SessionMapper;
 import info.FrostFS.sdk.services.ContextAccessor;
 import info.FrostFS.sdk.services.SessionClient;
-import info.FrostFS.sdk.tools.ClientEnvironment;
 
-import static info.FrostFS.sdk.RequestConstructor.addMetaHeader;
+import static info.FrostFS.sdk.tools.RequestConstructor.addMetaHeader;
-import static info.FrostFS.sdk.RequestSigner.sign;
+import static info.FrostFS.sdk.tools.RequestSigner.sign;
 
 public class SessionService extends ContextAccessor implements SessionClient {
     private final SessionServiceGrpc.SessionServiceBlockingStub serviceBlockingStub;

client/src/main/java/info/FrostFS/sdk/tools/GrpcClient.java

@@ -1,4 +1,4 @@
-package info.FrostFS.sdk;
+package info.FrostFS.sdk.tools;
 
 import io.grpc.Channel;
 import io.grpc.ChannelCredentials;
@@ -10,6 +10,7 @@ import java.net.URISyntaxException;
 import static java.util.Objects.isNull;
 
 public class GrpcClient {
+    private static final String ERROR_INVALID_HOST_TEMPLATE = "Host %s has invalid format. Error: %s";
 
     public static Channel initGrpcChannel(String host, ChannelCredentials creds) {
         try {
@@ -19,8 +20,7 @@ public class GrpcClient {
 
             return channelBuilder.usePlaintext().build();
         } catch (URISyntaxException exp) {
-            var message = String.format("Host %s has invalid format. Error: %s", host, exp.getMessage());
+            throw new IllegalArgumentException(String.format(ERROR_INVALID_HOST_TEMPLATE, host, exp.getMessage()));
-            throw new IllegalArgumentException(message);
         }
     }
 }

client/src/main/java/info/FrostFS/sdk/tools/MessageHelper.java

@@ -0,0 +1,15 @@
+package info.FrostFS.sdk.tools;
+
+import com.google.protobuf.Message;
+import com.google.protobuf.MessageOrBuilder;
+
+public class MessageHelper {
+
+    public static Message getField(MessageOrBuilder messageOrBuilder, String fieldName) {
+        return (Message) messageOrBuilder.getField(messageOrBuilder.getDescriptorForType().findFieldByName(fieldName));
+    }
+
+    public static void setField(Message.Builder builder, String fieldName, Object value) {
+        builder.setField(builder.getDescriptorForType().findFieldByName(fieldName), value);
+    }
+}

client/src/main/java/info/FrostFS/sdk/tools/RequestConstructor.java

@@ -1,36 +1,37 @@
-package info.FrostFS.sdk;
+package info.FrostFS.sdk.tools;
 
-import com.google.protobuf.AbstractMessage;
+import com.google.protobuf.Message;
 import frostFS.session.Types;
 import info.FrostFS.sdk.dto.MetaHeader;
+import info.FrostFS.sdk.jdo.ECDsa;
 import info.FrostFS.sdk.mappers.MetaHeaderMapper;
-import info.FrostFS.sdk.tools.ECDsa;
 
-import static info.FrostFS.sdk.RequestSigner.signMessagePart;
+import static info.FrostFS.sdk.constants.FieldConst.META_HEADER_FIELD_NAME;
+import static info.FrostFS.sdk.tools.MessageHelper.getField;
+import static info.FrostFS.sdk.tools.MessageHelper.setField;
+import static info.FrostFS.sdk.tools.RequestSigner.signMessagePart;
 import static java.util.Objects.isNull;
 
 public class RequestConstructor {
 
-    public static void addMetaHeader(AbstractMessage.Builder request) {
+    public static void addMetaHeader(Message.Builder request) {
         addMetaHeader(request, null);
     }
 
-    public static void addMetaHeader(AbstractMessage.Builder request, Types.RequestMetaHeader metaHeader) {
+    public static void addMetaHeader(Message.Builder request, Types.RequestMetaHeader metaHeader) {
         if (isNull(metaHeader) || metaHeader.getSerializedSize() == 0) {
             metaHeader = MetaHeaderMapper.toGrpcMessage(MetaHeader.getDefault());
-            var field = request.getDescriptorForType().findFieldByName("meta_header");
+            setField(request, META_HEADER_FIELD_NAME, metaHeader);
-            request.setField(field, metaHeader);
         }
     }
 
-    public static void addObjectSessionToken(AbstractMessage.Builder request,
+    public static void addObjectSessionToken(Message.Builder request,
                                              Types.SessionToken sessionToken,
                                              frostFS.refs.Types.ContainerID cid,
                                              frostFS.refs.Types.ObjectID oid,
                                              Types.ObjectSessionContext.Verb verb,
                                              ECDsa key) {
-        var headerField = request.getDescriptorForType().findFieldByName("meta_header");
+        var header = (Types.RequestMetaHeader) getField(request, META_HEADER_FIELD_NAME);
-        var header = (Types.RequestMetaHeader) request.getField(headerField);
         if (header.getSessionToken().getSerializedSize() > 0) {
             return;
         }
@@ -46,6 +47,6 @@ public class RequestConstructor {
                 .setBody(body)
                 .build();
 
-        request.setField(headerField, header.toBuilder().setSessionToken(sessionToken).build());
+        setField(request, META_HEADER_FIELD_NAME, header.toBuilder().setSessionToken(sessionToken).build());
     }
 }

client/src/main/java/info/FrostFS/sdk/tools/RequestSigner.java

@@ -1,9 +1,9 @@
-package info.FrostFS.sdk;
+package info.FrostFS.sdk.tools;
 
-import com.google.protobuf.AbstractMessage;
 import com.google.protobuf.ByteString;
+import com.google.protobuf.Message;
 import frostFS.session.Types;
-import info.FrostFS.sdk.tools.ECDsa;
+import info.FrostFS.sdk.jdo.ECDsa;
 import org.apache.commons.codec.digest.DigestUtils;
 import org.bouncycastle.asn1.sec.SECNamedCurves;
 import org.bouncycastle.asn1.sec.SECObjectIdentifiers;
@@ -15,17 +15,22 @@ import org.bouncycastle.crypto.signers.HMacDSAKCalculator;
 import java.math.BigInteger;
 import java.security.Signature;
 
+import static info.FrostFS.sdk.constants.CryptoConst.SIGNATURE_ALGORITHM;
+import static info.FrostFS.sdk.constants.FieldConst.*;
+import static info.FrostFS.sdk.tools.MessageHelper.getField;
+import static info.FrostFS.sdk.tools.MessageHelper.setField;
 import static org.bouncycastle.crypto.util.DigestFactory.createSHA256;
 import static org.bouncycastle.util.BigIntegers.asUnsignedByteArray;
 
 public class RequestSigner {
+    public static final String ERROR_UNSUPPORTED_TYPE_TEMPLATE = "Unsupported message type: %s";
     public static final int RFC6979_SIGNATURE_SIZE = 64;
 
     public static byte[] signData(ECDsa key, byte[] data) {
         var hash = new byte[65];
         hash[0] = 0x04;
         try {
-            Signature signature = Signature.getInstance("NONEwithECDSAinP1363Format");
+            Signature signature = Signature.getInstance(SIGNATURE_ALGORITHM);
             signature.initSign(key.getPrivateKey());
             signature.update(DigestUtils.sha512(data));
             byte[] sig = signature.sign();
@@ -62,7 +67,7 @@ public class RequestSigner {
         return signature;
     }
 
-    public static frostFS.refs.Types.SignatureRFC6979 signRFC6979(ECDsa key, AbstractMessage message) {
+    public static frostFS.refs.Types.SignatureRFC6979 signRFC6979(ECDsa key, Message message) {
         return frostFS.refs.Types.SignatureRFC6979.newBuilder()
                 .setKey(ByteString.copyFrom(key.getPublicKeyByte()))
                 .setSign(ByteString.copyFrom(signRFC6979(key, message.toByteArray())))
@@ -76,7 +81,7 @@ public class RequestSigner {
                 .build();
     }
 
-    public static frostFS.refs.Types.Signature signMessagePart(ECDsa key, AbstractMessage data) {
+    public static frostFS.refs.Types.Signature signMessagePart(ECDsa key, Message data) {
         var data2Sign = data.getSerializedSize() == 0 ? new byte[]{} : data.toByteArray();
         return frostFS.refs.Types.Signature.newBuilder()
                 .setKey(ByteString.copyFrom(key.getPublicKeyByte()))
@@ -84,39 +89,32 @@ public class RequestSigner {
                 .build();
     }
 
-    public static void sign(AbstractMessage.Builder request, ECDsa key) {
+    public static void sign(Message.Builder request, ECDsa key) {
-        var meta = (AbstractMessage) request.getField(request.getDescriptorForType().findFieldByName("meta_header"));
+        var meta = getField(request, META_HEADER_FIELD_NAME);
-        var body = (AbstractMessage) request.getField(request.getDescriptorForType().findFieldByName("body"));
+        var body = getField(request, BODY_FIELD_NAME);
-        var verify = (AbstractMessage) request.getField(request.getDescriptorForType().findFieldByName("verify_header"));
+        var verify = getField(request, VERIFY_HEADER_FIELD_NAME);
+        var verifyOrigin = getField(verify, ORIGIN_FIELD_NAME);
 
-        AbstractMessage.Builder verifyBuilder;
+        Message.Builder verifyBuilder;
         if (verify instanceof Types.RequestVerificationHeader) {
             verifyBuilder = Types.RequestVerificationHeader.newBuilder();
         } else if (verify instanceof Types.ResponseVerificationHeader) {
             verifyBuilder = Types.ResponseVerificationHeader.newBuilder();
         } else {
-            throw new IllegalArgumentException("Unsopported message type");
+            throw new IllegalArgumentException(
-        }
+                    String.format(ERROR_UNSUPPORTED_TYPE_TEMPLATE, verify.getClass().getName())
-
-        var verifyOrigin = (AbstractMessage) verify.getField(verify.getDescriptorForType().findFieldByName("origin"));
-        if (verifyOrigin.getSerializedSize() == 0) {
-            verifyBuilder.setField(
-                    verifyBuilder.getDescriptorForType().findFieldByName("body_signature"),
-                    signMessagePart(key, body)
             );
-        } else {
-            verifyBuilder.setField(verifyBuilder.getDescriptorForType().findFieldByName("origin"), verifyOrigin);
         }
 
-        verifyBuilder.setField(
+        if (verifyOrigin.getSerializedSize() == 0) {
-                verifyBuilder.getDescriptorForType().findFieldByName("meta_signature"),
+            setField(verifyBuilder, BODY_SIGNATURE_FIELD_NAME, signMessagePart(key, body));
-                signMessagePart(key, meta)
+        } else {
-        );
+            setField(verifyBuilder, ORIGIN_FIELD_NAME, verifyOrigin);
-        verifyBuilder.setField(
+        }
-                verifyBuilder.getDescriptorForType().findFieldByName("origin_signature"),
-                signMessagePart(key, verifyOrigin)
-        );
 
-        request.setField(request.getDescriptorForType().findFieldByName("verify_header"), verifyBuilder.build());
+        setField(verifyBuilder, META_SIGNATURE_FIELD_NAME, signMessagePart(key, meta));
+        setField(verifyBuilder, ORIGIN_SIGNATURE_FIELD_NAME, signMessagePart(key, verifyOrigin));
+        setField(request, VERIFY_HEADER_FIELD_NAME, verifyBuilder.build());
     }
+
 }

client/src/main/java/info/FrostFS/sdk/tools/Verifier.java

@@ -1,7 +1,7 @@
-package info.FrostFS.sdk;
+package info.FrostFS.sdk.tools;
 
-import com.google.protobuf.AbstractMessage;
+import com.google.protobuf.Message;
-import frostFS.refs.Types;
+import frostFS.session.Types;
 import info.FrostFS.sdk.mappers.StatusMapper;
 import org.apache.commons.codec.digest.DigestUtils;
 import org.bouncycastle.asn1.sec.SECNamedCurves;
@@ -17,17 +17,20 @@ import java.security.Signature;
 import java.util.Arrays;
 
 import static info.FrostFS.sdk.KeyExtension.getPublicKeyFromBytes;
+import static info.FrostFS.sdk.constants.CryptoConst.SIGNATURE_ALGORITHM;
+import static info.FrostFS.sdk.constants.FieldConst.*;
+import static info.FrostFS.sdk.tools.MessageHelper.getField;
 import static java.util.Objects.isNull;
 import static org.bouncycastle.crypto.util.DigestFactory.createSHA256;
 import static org.bouncycastle.util.BigIntegers.fromUnsignedByteArray;
 
 public class Verifier {
+    public static final String ERROR_WRONG_SIG_SIZE_TEMPLATE = "Wrong signature size. Expected length=%s, actual=%s";
+    public static final String ERROR_INVALID_RESPONSE = "Invalid response";
     public static final int RFC6979_SIG_SIZE = 64;
 
-    public static boolean verifyRFC6979(Types.SignatureRFC6979 signature, AbstractMessage message) {
+    public static boolean verifyRFC6979(frostFS.refs.Types.SignatureRFC6979 signature, Message data) {
-        return verifyRFC6979(
+        return verifyRFC6979(signature.getKey().toByteArray(), data.toByteArray(), signature.getSign().toByteArray());
-                signature.getKey().toByteArray(), message.toByteArray(), signature.getSign().toByteArray()
-        );
     }
 
     public static boolean verifyRFC6979(byte[] publicKey, byte[] data, byte[] sig) {
@@ -49,8 +52,7 @@ public class Verifier {
     private static BigInteger[] decodeSignature(byte[] sig) {
         if (sig.length != RFC6979_SIG_SIZE) {
             throw new IllegalArgumentException(
-                    String.format("Wrong signature size. Expected length=%s, actual=%s",
+                    String.format(ERROR_WRONG_SIG_SIZE_TEMPLATE, RFC6979_SIG_SIZE, sig.length)
-                            RFC6979_SIG_SIZE, sig.length)
             );
         }
 
@@ -61,42 +63,40 @@ public class Verifier {
         return rs;
     }
 
-    public static void checkResponse(AbstractMessage response) {
+    public static void checkResponse(Message response) {
         if (!verify(response)) {
-            throw new IllegalArgumentException("Invalid response");
+            throw new IllegalArgumentException(ERROR_INVALID_RESPONSE);
         }
-        var metaHeader = (frostFS.session.Types.ResponseMetaHeader) response
+
-                .getField(response.getDescriptorForType().findFieldByName("meta_header"));
+        var metaHeader = (Types.ResponseMetaHeader) getField(response, META_HEADER_FIELD_NAME);
         var status = StatusMapper.toModel(metaHeader.getStatus());
         if (!status.isSuccess()) {
             throw new IllegalArgumentException(status.toString());
         }
     }
 
-    public static boolean verify(AbstractMessage message) {
+    public static boolean verify(Message response) {
-        var body = (AbstractMessage) message.getField(message.getDescriptorForType().findFieldByName("body"));
+        var body = getField(response, BODY_FIELD_NAME);
-        var metaHeader = (frostFS.session.Types.ResponseMetaHeader)
+        var metaHeader = (Types.ResponseMetaHeader) getField(response, META_HEADER_FIELD_NAME);
-                message.getField(message.getDescriptorForType().findFieldByName("meta_header"));
+        var verifyHeader = (Types.ResponseVerificationHeader) getField(response, VERIFY_HEADER_FIELD_NAME);
-        var verifyHeader = (frostFS.session.Types.ResponseVerificationHeader)
-                message.getField(message.getDescriptorForType().findFieldByName("verify_header"));
 
         return verifyMatryoshkaLevel(body, metaHeader, verifyHeader);
     }
 
-    public static boolean verifyMatryoshkaLevel(AbstractMessage body,
+    public static boolean verifyMatryoshkaLevel(Message data,
                                                 frostFS.session.Types.ResponseMetaHeader meta,
                                                 frostFS.session.Types.ResponseVerificationHeader verification) {
         if (!verifyMessagePart(verification.getMetaSignature(), meta)) return false;
         var origin = verification.getOrigin();
         if (!verifyMessagePart(verification.getOriginSignature(), origin)) return false;
         if (origin.getSerializedSize() == 0) {
-            return verifyMessagePart(verification.getBodySignature(), body);
+            return verifyMessagePart(verification.getBodySignature(), data);
         }
         return verification.getBodySignature().getSerializedSize() == 0
-                && verifyMatryoshkaLevel(body, meta.getOrigin(), origin);
+                && verifyMatryoshkaLevel(data, meta.getOrigin(), origin);
     }
 
-    public static boolean verifyMessagePart(Types.Signature sig, AbstractMessage data) {
+    public static boolean verifyMessagePart(frostFS.refs.Types.Signature sig, Message data) {
         if (sig.getSerializedSize() == 0 || sig.getKey().isEmpty() || sig.getSign().isEmpty()) return false;
 
         var publicKey = getPublicKeyFromBytes(sig.getKey().toByteArray());
@@ -107,7 +107,7 @@ public class Verifier {
 
     public static boolean verifyData(PublicKey publicKey, byte[] data, byte[] sig) {
         try {
-            Signature signature = Signature.getInstance("NONEwithECDSAinP1363Format");
+            Signature signature = Signature.getInstance(SIGNATURE_ALGORITHM);
             signature.initVerify(publicKey);
             signature.update(DigestUtils.sha512(data));
             return signature.verify(Arrays.copyOfRange(sig, 1, sig.length));

cryptography/pom.xml

@@ -1,6 +1,6 @@
 <?xml version="1.0" encoding="UTF-8"?>
-<project xmlns="http://maven.apache.org/POM/4.0.0"
+<project xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
-         xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
+         xmlns="http://maven.apache.org/POM/4.0.0"
          xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 http://maven.apache.org/xsd/maven-4.0.0.xsd">
     <modelVersion>4.0.0</modelVersion>
     <parent>

cryptography/src/main/java/info/FrostFS/sdk/Helper.java

@@ -1,7 +1,7 @@
 package info.FrostFS.sdk;
 
-import com.google.protobuf.AbstractMessage;
 import com.google.protobuf.ByteString;
+import com.google.protobuf.Message;
 import org.bouncycastle.crypto.digests.RIPEMD160Digest;
 
 import java.math.BigInteger;
@@ -30,7 +30,7 @@ public class Helper {
         return getSha256Instance().digest(value);
     }
 
-    public static ByteString getSha256(AbstractMessage value) {
+    public static ByteString getSha256(Message value) {
         return ByteString.copyFrom(getSha256(value.toByteArray()));
     }
 

models/pom.xml

@@ -1,6 +1,6 @@
 <?xml version="1.0" encoding="UTF-8"?>
-<project xmlns="http://maven.apache.org/POM/4.0.0"
+<project xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
-         xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
+         xmlns="http://maven.apache.org/POM/4.0.0"
          xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 http://maven.apache.org/xsd/maven-4.0.0.xsd">
     <modelVersion>4.0.0</modelVersion>
     <parent>

models/src/main/java/info/FrostFS/sdk/constants/FieldConst.java

@@ -0,0 +1,11 @@
+package info.FrostFS.sdk.constants;
+
+public class FieldConst {
+    public static final String META_HEADER_FIELD_NAME = "meta_header";
+    public static final String META_SIGNATURE_FIELD_NAME = "meta_signature";
+    public static final String BODY_FIELD_NAME = "body";
+    public static final String BODY_SIGNATURE_FIELD_NAME = "body_signature";
+    public static final String ORIGIN_FIELD_NAME = "origin";
+    public static final String ORIGIN_SIGNATURE_FIELD_NAME = "origin_signature";
+    public static final String VERIFY_HEADER_FIELD_NAME = "verify_header";
+}