Initial commit for json serialization

pom.xml

@@ -12,7 +12,7 @@
     <groupId>org.lwes</groupId>
     <artifactId>lwes-java</artifactId>
     <packaging>jar</packaging>
-    <version>1.4.3-SNAPSHOT</version>
+    <version>1.4.4-SNAPSHOT</version>
     <name>lwes-java</name>
     <description>Lightweight event system, java implementation</description>
     <url>http://lwes.org</url>
@@ -48,6 +48,13 @@
     </developers>
 
     <dependencies>
+
+        <dependency>
+            <groupId>com.google.code.gson</groupId>
+            <artifactId>gson</artifactId>
+            <version>2.2.4</version>
+        </dependency>
+
         <dependency>
             <groupId>junit</groupId>
             <artifactId>junit</artifactId>

src/main/java/org/lwes/ArrayEvent.java

@@ -18,6 +18,7 @@
 import java.util.EnumMap;
 import java.util.Enumeration;
 import java.util.Iterator;
+import java.util.LinkedHashMap;
 import java.util.Map;
 import java.util.Map.Entry;
 import java.util.SortedSet;
@@ -26,6 +27,7 @@
 import org.apache.commons.lang3.mutable.MutableInt;
 import org.lwes.serializer.Deserializer;
 import org.lwes.serializer.DeserializerState;
+import org.lwes.serializer.JsonSerializer;
 import org.lwes.serializer.Serializer;
 import org.lwes.util.EncodedString;
 
@@ -38,6 +40,7 @@ public final class ArrayEvent extends DefaultEvent {
     private short encoding = DEFAULT_ENCODING;
     private static Map<ArrayEventStats, MutableInt> STATS =
             new EnumMap<ArrayEventStats, MutableInt>(ArrayEventStats.class);
+    private Map<String, BaseType> attributes;
 
     static {
         byte[] temp = new byte[256];
@@ -51,6 +54,7 @@ public final class ArrayEvent extends DefaultEvent {
     //  * UINT64|INT64|BOOLEAN|STRING)
 
     public ArrayEvent() {
+        attributes = new LinkedHashMap<String, BaseType>();
         length = getValueListIndex();
         setEncoding(DEFAULT_ENCODING);
         final MutableInt creations = STATS.get(ArrayEventStats.CREATIONS);
@@ -168,6 +172,7 @@ public void set(String key, FieldType type, Object value) {
                 if (oldType == type && type.isConstantSize()) {
                     // Modify the value in place, requiring no shifts.
                     Serializer.serializeValue(type, value, encoding, bytes, tokenIndex + 1);
+                    attributes.put(key, new BaseType(type, value));
                     return;
                 }
                 clear(key);
@@ -192,6 +197,7 @@ private void appendField(String key, FieldType type, Object value) {
             length += Serializer.serializeATTRIBUTEWORD(key, bytes, length);
             length += Serializer.serializeBYTE(type.token, bytes, length);
             length += Serializer.serializeValue(type, value, encoding, bytes, length);
+            attributes.put(key, new BaseType(type, value));
             setNumEventAttributes(getNumEventAttributes() + 1);
         }
         catch (ArrayIndexOutOfBoundsException e) {
@@ -679,4 +685,9 @@ public Object getValue() {
             return value;
         }
     }
+
+    public String toJson() {
+        return JsonSerializer.getInstance().toJson(getEventName(), attributes);
+    }
+
 }

src/main/java/org/lwes/Event.java

@@ -226,6 +226,8 @@ public interface Event extends Iterable<FieldAccessor> {
     void deserialize(DataInput stream, int length) throws IOException;
 
     int getBytesSize();
+
+    String toJson();
 
     // MISCELLANEOUS
 

src/main/java/org/lwes/EventFactory.java

@@ -13,6 +13,7 @@
 package org.lwes;
 
 import org.lwes.db.EventTemplateDB;
+import org.lwes.serializer.JsonDeserializer;
 
 import java.io.File;
 import java.io.InputStream;
@@ -189,5 +190,22 @@ public Event createEvent(byte[] bytes, boolean validate) throws EventSystemExcep
         }
         return new MapEvent(bytes, validate, eventTemplateDB);
     }
+
+    /**
+     * Create an event from its json representation
+     * @param json
+     * @param type
+     * @return
+     */
+    public Event createEventFromJson(String json, EventImplementation type){
+        JsonDeserializer deSerializer = JsonDeserializer.getInstance();
+        switch (type) {
+        case MAP_EVENT:
+            return deSerializer.fromJson(json, new MapEvent());
+        case ARRAY_EVENT:
+            return deSerializer.fromJson(json, new ArrayEvent());
+        }
+        return null;
+    }
 
 }

src/main/java/org/lwes/EventImplementation.java

@@ -0,0 +1,5 @@
+package org.lwes;
+
+public enum EventImplementation {
+    MAP_EVENT, ARRAY_EVENT;
+}

src/main/java/org/lwes/MapEvent.java

@@ -23,6 +23,7 @@
 import org.lwes.db.EventTemplateDB;
 import org.lwes.serializer.Deserializer;
 import org.lwes.serializer.DeserializerState;
+import org.lwes.serializer.JsonSerializer;
 import org.lwes.serializer.Serializer;
 
 public class MapEvent extends DefaultEvent {
@@ -606,4 +607,9 @@ public FieldType getType(String field) {
     public int getBytesSize() {
         return bytesStoreSize;
     }
+
+    public String toJson() {
+        return JsonSerializer.getInstance().toJson(name, attributes);
+    }
+
 }

src/main/java/org/lwes/TypeValue.java

@@ -0,0 +1,19 @@
+package org.lwes;
+
+public class TypeValue {
+
+    private String type;
+    private String value;
+    public String getType() {
+        return type;
+    }
+    public String getValue() {
+        return value;
+    }
+    public TypeValue(String type, String value) {
+        super();
+        this.type = type;
+        this.value = value;
+    }
+
+}

src/main/java/org/lwes/serializer/JsonDeserializer.java

@@ -0,0 +1,173 @@
+package org.lwes.serializer;
+
+import java.math.BigInteger;
+import java.util.HashMap;
+import java.util.Map;
+import java.util.Map.Entry;
+import java.util.Set;
+
+import org.apache.commons.lang3.StringUtils;
+import org.lwes.Event;
+import org.lwes.FieldType;
+import org.lwes.TypeValue;
+import org.lwes.util.IPAddress;
+
+import com.google.gson.Gson;
+import com.google.gson.GsonBuilder;
+import com.google.gson.JsonElement;
+import com.google.gson.JsonObject;
+import com.google.gson.JsonParser;
+
+public class JsonDeserializer {
+
+private static JsonDeserializer instance;
+
+    private Gson gson;
+    private JsonParser parser;
+
+    public static JsonDeserializer getInstance(){
+        if(instance == null){
+            synchronized (JsonSerializer.class) {
+                //Double-checked locking
+                if(instance == null)
+                    instance = new JsonDeserializer();
+            }
+        }
+        return instance;
+    }
+
+    private JsonDeserializer(){
+        parser = new JsonParser();
+        GsonBuilder bldr = new GsonBuilder();
+        gson = bldr.create();
+    }
+
+    public Event fromJson(String json, Event e){
+        try{
+            JsonObject root = parser.parse(json).getAsJsonObject();
+            String name = root.getAsJsonPrimitive("name").getAsString();
+            if(StringUtils.isEmpty(name))
+                return null;
+            JsonObject typedContainer = root.getAsJsonObject("typed");
+            if(typedContainer == null)
+                return null;
+            Map<String, TypeValue> typedElems = parseTyped(typedContainer);
+
+            e.setEventName(name);
+            for(Entry<String, TypeValue> element : typedElems.entrySet()){
+                FieldType ft = FieldType.byName(element.getValue().getType());
+                e.set(element.getKey(),
+                        FieldType.byName(element.getValue().getType()),
+                        getObjectForType(ft, element.getValue().getValue()));
+            }
+
+        }catch(Exception ex){
+            ex.printStackTrace();
+            return null;
+        }
+        return e;
+    }
+
+    Map<String, TypeValue> parseTyped(JsonObject typedContainer){
+        Set<Entry<String, JsonElement>> types = typedContainer.entrySet();
+        Map<String, TypeValue> typedElements = new HashMap<String, TypeValue>();
+        for(Entry<String, JsonElement> type : types){
+            TypeValue tv = getTypeValue(type.getValue().getAsJsonObject());
+            if(tv != null)
+                typedElements.put(type.getKey(), tv);
+        }
+        return typedElements;
+    }
+
+    TypeValue getTypeValue(JsonObject typedElement){
+        String type = typedElement.getAsJsonPrimitive("type").getAsString();
+        String value = typedElement.getAsJsonPrimitive("value").getAsString();
+        FieldType fType = FieldType.byName(type);
+        if(fType == null)
+            return null;
+        return new TypeValue(fType.name, value);
+    }
+
+    Object getObjectForType(FieldType ft, String str) {
+        //Giant switch statement dervied from Serializer.serializeValue's
+        //type system definition
+        switch (ft) {
+            case BOOLEAN:
+                return getObjectForType(str, Boolean.class);
+            case BYTE:
+                return getObjectForType(str, Byte.class);
+            case DOUBLE:
+                return getObjectForType(str, Double.class);
+            case FLOAT:
+                return getObjectForType(str, Float.class);
+            case INT16:
+                return getObjectForType(str, Short.class);
+            case INT32:
+                return getObjectForType(str, Integer.class);
+            case INT64:
+                return getObjectForType(str, Long.class);
+            case IPADDR:
+                return getObjectForType(str, IPAddress.class);
+            case STRING:
+                return getObjectForType(str, String.class);
+            case UINT16:
+                return getObjectForType(str, Integer.class);
+            case UINT32:
+                return getObjectForType(str, Long.class);
+            case UINT64:
+                return getObjectForType(str, BigInteger.class);
+            case BOOLEAN_ARRAY:
+                return getObjectForType(str, boolean[].class);
+            case BYTE_ARRAY:
+                return getObjectForType(str, byte[].class);
+            case DOUBLE_ARRAY:
+                return getObjectForType(str, double[].class);
+            case FLOAT_ARRAY:
+                return getObjectForType(str, float[].class);
+            case INT16_ARRAY:
+                return getObjectForType(str, short[].class);
+            case INT32_ARRAY:
+                return getObjectForType(str, int[].class);
+            case INT64_ARRAY:
+                return getObjectForType(str, long[].class);
+            case IP_ADDR_ARRAY:
+                return getObjectForType(str, IPAddress[].class);
+            case STRING_ARRAY:
+                return getObjectForType(str, String[].class);
+            case UINT16_ARRAY:
+                return getObjectForType(str, int[].class);
+            case UINT32_ARRAY:
+                return getObjectForType(str, long[].class);
+            case UINT64_ARRAY:
+                return getObjectForType(str, BigInteger[].class);
+            case NBOOLEAN_ARRAY:
+                return getObjectForType(str, Boolean[].class);
+            case NBYTE_ARRAY:
+                return getObjectForType(str, Byte[].class);
+            case NDOUBLE_ARRAY:
+                return getObjectForType(str, Double[].class);
+            case NFLOAT_ARRAY:
+                return getObjectForType(str, Float[].class);
+            case NINT16_ARRAY:
+                return getObjectForType(str, Short[].class);
+            case NINT32_ARRAY:
+                return getObjectForType(str, Integer[].class);
+            case NINT64_ARRAY:
+                return getObjectForType(str, Long[].class);
+            case NSTRING_ARRAY:
+                return getObjectForType(str, String[].class);
+            case NUINT16_ARRAY:
+                return getObjectForType(str, Integer[].class);
+            case NUINT32_ARRAY:
+                return getObjectForType(str, Long[].class);
+            case NUINT64_ARRAY:
+                return getObjectForType(str, BigInteger[].class);
+            default:
+                return str;
+        }
+    }
+
+    Object getObjectForType(String str, Class clz){
+        return gson.fromJson(str, clz);
+    }
+}