Add new message format support [ECR-3473]: (#1085)

Add support for new protocol buffers-based
message format. SignedMessage supports
any Exonum message; whilst TransactionMessage
(including ParsedTransactionMessage) represent
a transaction message and allow to access
any properties of the transaction.

As transaction payloads (arguments) are often
protocol buffer messages, some methods
now have protobuf-specific overloads for
higher convenience
(e.g., TransactionMessage.Builder#payload).

Author: dmitry-timofeev

exonum-java-binding/common/checkstyle-suppressions.xml

@@ -14,4 +14,7 @@
     <!-- Allow underscore in the class name so that IDEs work properly. -->
     <suppress files="Message_Builder2Test\.java" checks="TypeName"/>
 
+    <!-- Allow `aInstance` name -->
+    <suppress files="SignedMessageTest.java|ParsedTransactionMessageTest.java|JsonSerializerTest.java"
+      checks="MethodName"/>
 </suppressions>

exonum-java-binding/common/pom.xml

@@ -142,6 +142,7 @@
         <executions>
           <execution>
             <goals>
+              <goal>compile</goal>
               <goal>test-compile</goal>
             </goals>
             <configuration>

exonum-java-binding/common/src/main/java/com/exonum/binding/common/crypto/AbstractKey.java

@@ -19,6 +19,8 @@
 import static com.exonum.binding.common.crypto.CryptoUtils.byteArrayToHex;
 import static com.google.common.base.Preconditions.checkArgument;
 
+import com.exonum.binding.common.hash.Funnel;
+import com.exonum.binding.common.hash.PrimitiveSink;
 import java.util.Arrays;
 
 /**
@@ -78,4 +80,20 @@ public final int hashCode() {
   public String toString() {
     return byteArrayToHex(rawKey);
   }
+
+  /**
+   * Returns a funnel for any key.
+   */
+  public static Funnel<AbstractKey> keyFunnel() {
+    return KeyFunnel.INSTANCE;
+  }
+
+  private enum KeyFunnel implements Funnel<AbstractKey> {
+    INSTANCE;
+
+    @Override
+    public void funnel(AbstractKey from, PrimitiveSink into) {
+      into.putBytes(from.toBytesNoCopy());
+    }
+  }
 }

exonum-java-binding/common/src/main/java/com/exonum/binding/common/message/BinaryTransactionMessage.java

@@ -0,0 +1,43 @@
+/*
+ * Copyright 2019 The Exonum Team
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package com.exonum.binding.common.message;
+
+import com.exonum.binding.common.hash.Funnel;
+import com.exonum.binding.common.hash.PrimitiveSink;
+import com.google.protobuf.ByteString;
+
+/**
+ * A funnel for ByteStrings which puts their bytes to the sink without copying.
+ */
+enum ByteStringFunnel implements Funnel<ByteString> {
+
+  INSTANCE;
+
+  static Funnel<ByteString> byteStringFunnel() {
+    return INSTANCE;
+  }
+
+  @Override
+  public void funnel(ByteString from, PrimitiveSink into) {
+    // We use #asReadOnlyByteBuffer instead of #asReadOnlyByteBufferList because
+    // it is not expected that in our main usages of this funnel a RopeByteString will
+    // appear.
+    // If this funnel is used more widely, it might be reasonable to use #asReadOnlyByteBufferList
+    // to prevent copying in case of RopeByteString.
+    into.putBytes(from.asReadOnlyByteBuffer());
+  }
+}