BJ-88: Add serializer and reader interface (#8)

* BJ-88: Add interfaces

* BJ-88: Fix serializer interface

* BJ-88: Change interface logic

src/main/java/com/rbkmoney/kebab/Kebab.java

@@ -1,8 +1,8 @@
 package com.rbkmoney.kebab;
 
-import com.rbkmoney.kebab.serializer.TBaseSerializer;
-import com.rbkmoney.kebab.writer.JsonStructWriter;
-import com.rbkmoney.kebab.writer.MsgPackWriter;
+import com.rbkmoney.kebab.handler.JsonStructHandler;
+import com.rbkmoney.kebab.handler.MsgPackHandler;
+import com.rbkmoney.kebab.processor.TBaseStructProcessor;
 import org.apache.thrift.TBase;
 
 import java.io.ByteArrayOutputStream;
@@ -17,11 +17,9 @@ public class Kebab<T extends TBase> {
     public String toJson(T src) {
         try {
             StringWriter writer = new StringWriter();
-            Serializer serializer = new TBaseSerializer();
-            JsonStructWriter jsonStructWriter = new JsonStructWriter(writer);
-            serializer.write(jsonStructWriter, src);
-            jsonStructWriter.close();
-            return writer.toString();
+            TBaseStructProcessor structProcessor = new TBaseStructProcessor();
+            JsonStructHandler jsonStructHandler = new JsonStructHandler(writer);
+            return  structProcessor.process(src, jsonStructHandler);
         } catch (IOException ex) {
             throw new RuntimeException(ex);
         }
@@ -30,11 +28,10 @@ public class Kebab<T extends TBase> {
     public byte[] toMsgPack(T src, boolean useDict) {
         try {
             ByteArrayOutputStream os = new ByteArrayOutputStream();
-            MsgPackWriter writer = new MsgPackWriter(os, true, true);
-            TBaseSerializer serializer = new TBaseSerializer();
+            MsgPackHandler handler = new MsgPackHandler(os, true, true);
+            TBaseStructProcessor serializer = new TBaseStructProcessor();
 
-            serializer.write(writer, src);
-            writer.close();
+            serializer.process(src, handler);
             return os.toByteArray();
 
         } catch (IOException e) {
@@ -42,10 +39,10 @@ public class Kebab<T extends TBase> {
         }
     }
 
-    public byte[] write(T src, StructWriter writer) {
-        Serializer serializer = new TBaseSerializer();
+    public byte[] write(T src, StructHandler writer) {
+        StructProcessor structProcessor = new TBaseStructProcessor();
         try {
-            serializer.write(writer, src);
+            structProcessor.process(src, writer);
             return new byte[0];
         } catch (IOException ex) {
             throw new RuntimeException(ex);

src/main/java/com/rbkmoney/kebab/Serializer.java

@@ -1,12 +0,0 @@
-package com.rbkmoney.kebab;
-
-import java.io.IOException;
-
-/**
- * Created by tolkonepiu on 27/01/2017.
- */
-public interface Serializer<T> {
-
-    void write(StructWriter out, T value) throws IOException;
-
-}

src/main/java/com/rbkmoney/kebab/StructHandler.java

@@ -1,12 +1,11 @@
 package com.rbkmoney.kebab;
 
-import java.io.Closeable;
 import java.io.IOException;
 
 /**
  * Created by tolkonepiu on 26/01/2017.
  */
-public interface StructWriter extends Closeable {
+public interface StructHandler<R> {
 
     void beginStruct(int size) throws IOException;
 
@@ -48,4 +47,6 @@ public interface StructWriter extends Closeable {
 
     void nullValue() throws IOException;
 
+    R getResult() throws IOException;
+
 }

src/main/java/com/rbkmoney/kebab/StructProcessor.java

@@ -0,0 +1,12 @@
+package com.rbkmoney.kebab;
+
+import java.io.IOException;
+
+/**
+ * Created by tolkonepiu on 27/01/2017.
+ */
+public interface StructProcessor<S> {
+
+    <R> R process(S value, StructHandler<R> handler) throws IOException;
+
+}

src/main/java/com/rbkmoney/kebab/handler/JsonStructHandler.java

@@ -1,7 +1,7 @@
-package com.rbkmoney.kebab.writer;
+package com.rbkmoney.kebab.handler;
 
 import com.rbkmoney.kebab.ByteStack;
-import com.rbkmoney.kebab.StructWriter;
+import com.rbkmoney.kebab.StructHandler;
 import com.rbkmoney.kebab.ThriftType;
 import com.rbkmoney.kebab.exception.BadFormatException;
 
@@ -13,7 +13,7 @@ import java.util.Objects;
 /**
  * Created by tolkonepiu on 27/01/2017.
  */
-public class JsonStructWriter implements StructWriter {
+public class JsonStructHandler implements StructHandler<String> {
 
     static final byte EMPTY_STRUCT = 1;
 
@@ -43,11 +43,11 @@ public class JsonStructWriter implements StructWriter {
         stack.push(EMPTY_DOCUMENT);
     }
 
-    public JsonStructWriter(Writer out) {
+    public JsonStructHandler(Writer out) {
         this(out, false);
     }
 
-    public JsonStructWriter(Writer out, boolean pretty) {
+    public JsonStructHandler(Writer out, boolean pretty) {
         Objects.requireNonNull(out, "Writer must not be null");
         this.out = out;
         this.pretty = pretty;
@@ -262,11 +262,14 @@ public class JsonStructWriter implements StructWriter {
     }
 
     @Override
-    public void close() throws IOException {
+    public String getResult() throws IOException {
         out.close();
 
         if (stack.size() > 1 || stack.size() == 1 && stack.peek() != NONEMPTY_DOCUMENT) {
             throw new BadFormatException();
         }
+
+        return out.toString();
     }
+
 }

src/main/java/com/rbkmoney/kebab/handler/MsgPackHandler.java

@@ -1,6 +1,6 @@
-package com.rbkmoney.kebab.writer;
+package com.rbkmoney.kebab.handler;
 
-import com.rbkmoney.kebab.StructWriter;
+import com.rbkmoney.kebab.StructHandler;
 import com.rbkmoney.kebab.exception.BadFormatException;
 import gnu.trove.map.hash.TObjectCharHashMap;
 import org.msgpack.core.MessagePack;
@@ -9,13 +9,13 @@ import org.msgpack.core.MessagePacker;
 import java.io.IOException;
 import java.io.OutputStream;
 
-import static com.rbkmoney.kebab.writer.StringUtil.compressAsciiString;
-import static com.rbkmoney.kebab.writer.StringUtil.toAsciiBytes;
+import static com.rbkmoney.kebab.handler.StringUtil.compressAsciiString;
+import static com.rbkmoney.kebab.handler.StringUtil.toAsciiBytes;
 
 /**
  * Created by vpankrashkin on 31.01.17.
  */
-public class MsgPackWriter implements StructWriter {
+public class MsgPackHandler implements StructHandler<OutputStream> {
     private static final byte nop = 0;
     private static final byte startStruct = 1;
     private static final byte endStruct = 2;
@@ -39,7 +39,7 @@ public class MsgPackWriter implements StructWriter {
     private final char noDictEntryValue = 0;
     private char nextDictIdx = 0;
 
-    public MsgPackWriter(OutputStream stream, boolean autoClose, boolean useDictionary) {
+    public MsgPackHandler(OutputStream stream, boolean autoClose, boolean useDictionary) {
         this.autoClose = autoClose;
         this.msgPacker = MessagePack.newDefaultPacker(stream);
         this.useDictionary = useDictionary;
@@ -58,7 +58,7 @@ public class MsgPackWriter implements StructWriter {
 
     /**
      * @param size if >= 0, expected to be defined list size; if < 0, means stream mode with not fixed size
-     * */
+     */
     @Override
     public void beginList(int size) throws IOException {
         if (size >= 0) {
@@ -111,7 +111,7 @@ public class MsgPackWriter implements StructWriter {
 
     /**
      * @param name - only ASCII symbols expected
-     * */
+     */
     @Override
     public void name(String name) throws IOException {
         int length = name.length();
@@ -180,12 +180,14 @@ public class MsgPackWriter implements StructWriter {
     }
 
     @Override
-    public void close() throws IOException {
+    public OutputStream getResult() throws IOException {
         if (autoClose) {
             msgPacker.close();
         } else {
             msgPacker.flush();
         }
+
+        return null;
     }
 
 }

src/main/java/com/rbkmoney/kebab/handler/StringUtil.java

@@ -1,4 +1,4 @@
-package com.rbkmoney.kebab.writer;
+package com.rbkmoney.kebab.handler;
 
 import com.rbkmoney.kebab.exception.BadFormatException;
 

src/main/java/com/rbkmoney/kebab/processor/TBaseStructProcessor.java

@@ -1,7 +1,7 @@
-package com.rbkmoney.kebab.serializer;
+package com.rbkmoney.kebab.processor;
 
-import com.rbkmoney.kebab.Serializer;
-import com.rbkmoney.kebab.StructWriter;
+import com.rbkmoney.kebab.StructProcessor;
+import com.rbkmoney.kebab.StructHandler;
 import com.rbkmoney.kebab.ThriftType;
 import org.apache.thrift.TBase;
 import org.apache.thrift.TFieldIdEnum;
@@ -16,19 +16,21 @@ import java.util.Set;
 /**
  * Created by tolkonepiu on 27/01/2017.
  */
-public class TBaseSerializer implements Serializer<TBase> {
+public class TBaseStructProcessor implements StructProcessor<TBase> {
 
     @Override
-    public void write(StructWriter out, TBase value) throws IOException {
+    public <R> R process(TBase value, StructHandler<R> handler) throws IOException {
         if (value == null) {
-            out.nullValue();
-            return;
+            handler.nullValue();
+            return null;
         }
 
-        writeStruct(out, value);
+        writeStruct(handler, value);
+
+        return handler.getResult();
     }
 
-    private void writeStruct(StructWriter out, TBase value) throws IOException {
+    private void writeStruct(StructHandler out, TBase value) throws IOException {
         TFieldIdEnum[] tFieldIdEnums = value.getFields();
         Map<TFieldIdEnum, FieldMetaData> fieldMetaDataMap = value.getFieldMetaData();
         int size = getFieldsCount(value, tFieldIdEnums);
@@ -57,7 +59,7 @@ public class TBaseSerializer implements Serializer<TBase> {
         return size;
     }
 
-    private void write(StructWriter out, Object object, FieldValueMetaData fieldValueMetaData) throws IOException {
+    private void write(StructHandler out, Object object, FieldValueMetaData fieldValueMetaData) throws IOException {
         if (object == null) {
             out.nullValue();
             return;
@@ -112,7 +114,7 @@ public class TBaseSerializer implements Serializer<TBase> {
         }
     }
 
-    private void writeSet(StructWriter out, Set objectSet, SetMetaData metaData) throws IOException {
+    private void writeSet(StructHandler out, Set objectSet, SetMetaData metaData) throws IOException {
         out.beginList(objectSet.size());
         for (Object object : objectSet) {
             write(out, object, metaData.getElementMetaData());
@@ -120,7 +122,7 @@ public class TBaseSerializer implements Serializer<TBase> {
         out.endList();
     }
 
-    private void writeList(StructWriter out, List objectList, ListMetaData metaData) throws IOException {
+    private void writeList(StructHandler out, List objectList, ListMetaData metaData) throws IOException {
         out.beginList(objectList.size());
         for (Object object : objectList) {
             write(out, object, metaData.getElementMetaData());
@@ -128,7 +130,7 @@ public class TBaseSerializer implements Serializer<TBase> {
         out.endList();
     }
 
-    private void writeMap(StructWriter out, Map objectMap, MapMetaData metaData) throws IOException {
+    private void writeMap(StructHandler out, Map objectMap, MapMetaData metaData) throws IOException {
         out.beginMap(objectMap.size());
         for (Map.Entry entry : (Set<Map.Entry>) objectMap.entrySet()) {
             out.beginKey();

src/test/java/com/rbkmoney/kebab/KebabTest.java

@@ -1,8 +1,8 @@
 package com.rbkmoney.kebab;
 
-import com.rbkmoney.kebab.serializer.TBaseSerializer;
+import com.rbkmoney.kebab.processor.TBaseStructProcessor;
 import com.rbkmoney.kebab.test.*;
-import com.rbkmoney.kebab.writer.WriterStub;
+import com.rbkmoney.kebab.handler.HandlerStub;
 import org.apache.thrift.TException;
 import org.apache.thrift.TSerializer;
 import org.apache.thrift.protocol.TBinaryProtocol;
@@ -29,7 +29,7 @@ public class KebabTest {
     public void tBaseSerializerTest() throws IOException {
         TestObject testObject = getTestObject();
         long start = System.currentTimeMillis();
-        new TBaseSerializer().write(new MockStructWriter(), testObject);
+        new TBaseStructProcessor().process(testObject, new MockStructHandler());
         long end = System.currentTimeMillis();
         System.out.println("TBaseSerializer: execution time " + (end - start) + " ms");
     }
@@ -104,7 +104,7 @@ public class KebabTest {
         boolean useDict = true;
         TestObject testObject = getTestObject(100, () -> Status.unknown(new Unknown("SomeData")));
         //warmup
-        WriterStub writerStub = new WriterStub();
+        HandlerStub writerStub = new HandlerStub();
         TSerializer serializer = new TSerializer(new TBinaryProtocol.Factory());
         IntConsumer stubConsumer = i -> kebab.write(testObject, writerStub);
         IntConsumer msgPackConsumer = i -> kebab.toMsgPack(testObject, useDict);

src/test/java/com/rbkmoney/kebab/MockStructHandler.java

@@ -5,7 +5,7 @@ import java.io.IOException;
 /**
  * Created by tolkonepiu on 03/02/2017.
  */
-public class MockStructWriter implements StructWriter {
+public class MockStructHandler implements StructHandler {
     @Override
     public void beginStruct(int size) throws IOException {
         //do nothing
@@ -107,7 +107,7 @@ public class MockStructWriter implements StructWriter {
     }
 
     @Override
-    public void close() throws IOException {
-        //do nothing
+    public Object getResult() throws IOException {
+        return null;
     }
 }

src/test/java/com/rbkmoney/kebab/handler/HandlerStub.java

@@ -1,13 +1,13 @@
-package com.rbkmoney.kebab.writer;
+package com.rbkmoney.kebab.handler;
 
-import com.rbkmoney.kebab.StructWriter;
+import com.rbkmoney.kebab.StructHandler;
 
 import java.io.IOException;
 
 /**
  * Created by vpankrashkin on 03.02.17.
  */
-public class WriterStub implements StructWriter {
+public class HandlerStub implements StructHandler {
     @Override
     public void beginStruct(int size) throws IOException {
 
@@ -109,7 +109,8 @@ public class WriterStub implements StructWriter {
     }
 
     @Override
-    public void close() throws IOException {
+    public Object getResult() throws IOException {
+        return null;
+    }
 
 }
-}

src/test/java/com/rbkmoney/kebab/handler/StringUtilCompressingTest.java

@@ -1,4 +1,4 @@
-package com.rbkmoney.kebab.writer;
+package com.rbkmoney.kebab.handler;
 
 import com.rbkmoney.kebab.exception.BadFormatException;
 import org.junit.Test;
@@ -8,8 +8,8 @@ import org.junit.runners.Parameterized;
 import java.util.Arrays;
 import java.util.Collection;
 
-import static com.rbkmoney.kebab.writer.StringUtil.intToString;
-import static com.rbkmoney.kebab.writer.StringUtil.isAsciiString;
+import static com.rbkmoney.kebab.handler.StringUtil.intToString;
+import static com.rbkmoney.kebab.handler.StringUtil.isAsciiString;
 import static org.junit.Assert.*;
 import static java.lang.System.*;