Introduce composed JsonPatchOperation as opposed to inherited

src/main/java/com/github/fge/jsonpatch/action/JsonPatchOperationAction.java

@@ -0,0 +1,15 @@
+package com.github.fge.jsonpatch.action;
+
+import com.fasterxml.jackson.databind.JsonNode;
+import com.fasterxml.jackson.databind.JsonSerializable;
+import com.github.fge.jsonpatch.JsonPatchException;
+import com.github.fge.jsonpatch.operation.policy.PathMissingPolicy;
+
+/**
+ *
+ */
+public interface JsonPatchOperationAction extends JsonSerializable
+{
+    public JsonNode apply(final JsonNode node, final PathMissingPolicy pathMissingPolicy)
+        throws JsonPatchException;
+}

src/main/java/com/github/fge/jsonpatch/action/OmitAction.java

@@ -0,0 +1,93 @@
+package com.github.fge.jsonpatch.action;
+
+import com.fasterxml.jackson.core.JsonGenerator;
+import com.fasterxml.jackson.core.JsonProcessingException;
+import com.fasterxml.jackson.databind.JsonNode;
+import com.fasterxml.jackson.databind.JsonSerializable;
+import com.fasterxml.jackson.databind.SerializerProvider;
+import com.fasterxml.jackson.databind.jsontype.TypeSerializer;
+import com.fasterxml.jackson.databind.node.ArrayNode;
+import com.fasterxml.jackson.databind.node.MissingNode;
+import com.fasterxml.jackson.databind.node.ObjectNode;
+import com.github.fge.jackson.JsonNumEquals;
+import com.github.fge.jackson.jsonpointer.JsonPointer;
+import com.github.fge.jsonpatch.JsonPatchException;
+import com.github.fge.jsonpatch.JsonPatchMessages;
+import com.github.fge.jsonpatch.operation.policy.PathMissingPolicy;
+import com.github.fge.jsonpatch.properties.PathValueProperties;
+import com.github.fge.msgsimple.bundle.MessageBundle;
+import com.github.fge.msgsimple.load.MessageBundles;
+import com.google.common.base.Equivalence;
+import com.google.common.collect.Iterables;
+
+import java.io.IOException;
+
+public final class OmitAction
+        implements JsonPatchOperationAction
+{
+    private final PathValueProperties properties;
+
+    private static final MessageBundle BUNDLE
+        = MessageBundles.getBundle(JsonPatchMessages.class);
+    private static final Equivalence<JsonNode> EQUIVALENCE
+        = JsonNumEquals.getInstance();
+
+    public OmitAction(final PathValueProperties properties)
+    {
+        this.properties = properties;
+    }
+
+    public JsonNode apply(final JsonNode node, final PathMissingPolicy pathMissingPolicy)
+        throws JsonPatchException
+    {
+        final String op = properties.getOp();
+        final JsonPointer path = properties.getPath();
+        final JsonNode value = properties.getValue();
+
+        final JsonNode ret = node.deepCopy();
+        if (path.isEmpty()) {
+            if (EQUIVALENCE.equivalent(ret, value)) {
+                return MissingNode.getInstance();
+            } else {
+                return ret;
+            }
+        }
+        final JsonNode valueAtPath = path.path(ret);
+        if (valueAtPath.isMissingNode()) {
+            switch (pathMissingPolicy) {
+                case THROW:
+                    throw new JsonPatchException(BUNDLE.getMessage(
+                        "jsonPatch.noSuchPath"));
+                case SKIP:
+                    return ret;
+                default:
+                    throw new JsonPatchException(BUNDLE.getMessage(
+                        "jsonPatch.invalidPolicy"));
+            }
+        }
+
+        if (EQUIVALENCE.equivalent(valueAtPath, value)) {
+            final JsonNode parent = path.parent().get(ret);
+            final String rawToken = Iterables.getLast(path).getToken().getRaw();
+            if (parent.isObject())
+                ((ObjectNode) parent).remove(rawToken);
+            else
+                ((ArrayNode) parent).remove(Integer.parseInt(rawToken));
+        }
+        return ret;
+    }
+
+    public final void serialize(final JsonGenerator jgen,
+        final SerializerProvider provider)
+        throws IOException, JsonProcessingException
+    {
+        properties.serialize(jgen, provider);
+    }
+
+    public final void serializeWithType(final JsonGenerator jgen,
+        final SerializerProvider provider, final TypeSerializer typeSer)
+        throws IOException, JsonProcessingException
+    {
+        properties.serializeWithType(jgen, provider, typeSer);
+    }
+}

src/main/java/com/github/fge/jsonpatch/operation/JsonPatchOperationComposed.java

@@ -0,0 +1,47 @@
+package com.github.fge.jsonpatch.operation;
+
+import com.fasterxml.jackson.core.JsonGenerator;
+import com.fasterxml.jackson.core.JsonProcessingException;
+import com.fasterxml.jackson.databind.JsonNode;
+import com.fasterxml.jackson.databind.SerializerProvider;
+import com.fasterxml.jackson.databind.jsontype.TypeSerializer;
+import com.github.fge.jsonpatch.JsonPatchException;
+import com.github.fge.jsonpatch.action.JsonPatchOperationAction;
+import com.github.fge.jsonpatch.operation.policy.PathMissingPolicy;
+
+import java.io.IOException;
+
+/**
+ * TODO: rename me!
+ */
+public class JsonPatchOperationComposed implements JsonPatchOperation
+{
+    private JsonPatchOperationAction action;
+    private PathMissingPolicy pathMissingPolicy;
+
+    public JsonPatchOperationComposed(JsonPatchOperationAction action, PathMissingPolicy pathMissingPolicy)
+    {
+        this.action = action;
+        this.pathMissingPolicy = pathMissingPolicy;
+    }
+
+    public JsonNode apply(final JsonNode node)
+            throws JsonPatchException
+    {
+        return action.apply(node, pathMissingPolicy);
+    }
+
+    public final void serialize(final JsonGenerator jgen,
+        final SerializerProvider provider)
+        throws IOException, JsonProcessingException
+    {
+        action.serialize(jgen, provider);
+    }
+
+    public final void serializeWithType(final JsonGenerator jgen,
+        final SerializerProvider provider, final TypeSerializer typeSer)
+        throws IOException, JsonProcessingException
+    {
+        action.serializeWithType(jgen, provider, typeSer);
+    }
+}

src/main/java/com/github/fge/jsonpatch/operation/JsonPatchOperationFactory.java

@@ -11,12 +11,6 @@ public interface JsonPatchOperationFactory
      */
     public String getOperationName();
 
-    /**
-     * Gets the class of JsonPatchOperation that this factory will create.
-     * @return
-     */
-    public Class<? extends JsonPatchOperation> getOperationClass();
-
     /**
      * Creates a JsonPatchOperation from a JsonNode
      * @param node The JsonNode to create the JsonPatchOperation from

src/main/java/com/github/fge/jsonpatch/operation/JsonPatchOperationFactoryBase.java

@@ -18,6 +18,12 @@ public abstract class JsonPatchOperationFactoryBase implements JsonPatchOperatio
     private static final MessageBundle BUNDLE
         = MessageBundles.getBundle(JsonPatchMessages.class);
 
+    /**
+     * Gets the class of JsonPatchOperation that this factory will create.
+     * @return
+     */
+    public abstract Class<? extends JsonPatchOperation> getOperationClass();
+
     public JsonPatchOperation create(JsonNode node)
         throws JsonPatchException
     {

src/main/java/com/github/fge/jsonpatch/operation/OmitOperationFactory.java

@@ -1,13 +1,34 @@
 package com.github.fge.jsonpatch.operation;
 
-public final class OmitOperationFactory extends JsonPatchOperationFactoryBase
+import com.fasterxml.jackson.databind.JsonNode;
+import com.github.fge.jackson.JacksonUtils;
+import com.github.fge.jsonpatch.JsonPatchException;
+import com.github.fge.jsonpatch.JsonPatchMessages;
+import com.github.fge.jsonpatch.action.OmitAction;
+import com.github.fge.jsonpatch.operation.policy.PathMissingPolicy;
+import com.github.fge.jsonpatch.properties.PathValueProperties;
+import com.github.fge.msgsimple.bundle.MessageBundle;
+import com.github.fge.msgsimple.load.MessageBundles;
+
+import java.io.IOException;
+
+public final class OmitOperationFactory implements JsonPatchOperationFactory
 {
+    private static final MessageBundle BUNDLE
+            = MessageBundles.getBundle(JsonPatchMessages.class);
+
     public String getOperationName()
     {
         return OmitOperation.OPERATION_NAME;
     }
-    public Class<? extends JsonPatchOperation> getOperationClass()
+    public JsonPatchOperation create(JsonNode node)
+            throws JsonPatchException
     {
-        return OmitOperation.class;
+        try {
+            PathValueProperties properties = JacksonUtils.getReader().withType(PathValueProperties.class).readValue(node);
+            return new JsonPatchOperationComposed(new OmitAction(properties), PathMissingPolicy.THROW);
+        } catch (IOException e) {
+            throw new JsonPatchException(BUNDLE.getMessage("jsonPatch.deserFailed"), e);
+        }
     }
 }

src/main/java/com/github/fge/jsonpatch/operation/policy/PathMissingPolicy.java

@@ -5,5 +5,5 @@
  */
 public enum PathMissingPolicy
 {
-    THROW, SKIP
+    THROW, SKIP, NOT_APPLICABLE
 }

src/main/java/com/github/fge/jsonpatch/properties/JsonPatchOperationProperties.java

@@ -0,0 +1,10 @@
+package com.github.fge.jsonpatch.properties;
+
+import com.fasterxml.jackson.databind.JsonSerializable;
+
+/**
+ *
+ */
+interface JsonPatchOperationProperties extends JsonSerializable
+{
+}

src/main/java/com/github/fge/jsonpatch/properties/PathValueProperties.java

@@ -0,0 +1,87 @@
+package com.github.fge.jsonpatch.properties;
+
+import com.fasterxml.jackson.annotation.JsonCreator;
+import com.fasterxml.jackson.annotation.JsonProperty;
+import com.fasterxml.jackson.core.JsonGenerator;
+import com.fasterxml.jackson.core.JsonProcessingException;
+import com.fasterxml.jackson.databind.JsonNode;
+import com.fasterxml.jackson.databind.SerializerProvider;
+import com.fasterxml.jackson.databind.annotation.JsonSerialize;
+import com.fasterxml.jackson.databind.jsontype.TypeSerializer;
+import com.github.fge.jackson.jsonpointer.JsonPointer;
+import com.github.fge.jsonpatch.JsonPatchMessages;
+import com.github.fge.msgsimple.bundle.MessageBundle;
+import com.github.fge.msgsimple.load.MessageBundles;
+
+import java.io.IOException;
+
+/**
+ *
+ */
+public class PathValueProperties
+        implements JsonPatchOperationProperties
+{
+    protected static final MessageBundle BUNDLE
+        = MessageBundles.getBundle(JsonPatchMessages.class);
+
+    protected final String op;
+
+    protected final JsonPointer path;
+
+    @JsonSerialize
+    protected final JsonNode value;
+
+    /**
+     * @param op operation name
+     * @param path affected path
+     * @param value JSON value
+     */
+    @JsonCreator
+    public PathValueProperties(@JsonProperty("op") final String op,
+                               @JsonProperty("path") final JsonPointer path,
+                               @JsonProperty("value") final JsonNode value)
+    {
+        this.op = op;
+        this.path = path;
+        this.value = value.deepCopy();
+    }
+
+    public String getOp()
+    {
+        return op;
+    }
+
+    public JsonPointer getPath()
+    {
+        return path;
+    }
+
+    public JsonNode getValue()
+    {
+        return value.deepCopy();
+    }
+
+    public final void serialize(final JsonGenerator jgen,
+        final SerializerProvider provider)
+        throws IOException, JsonProcessingException
+    {
+        jgen.writeStartObject();
+        jgen.writeStringField("op", op);
+        jgen.writeStringField("path", path.toString());
+        jgen.writeFieldName("value");
+        jgen.writeTree(value);
+        jgen.writeEndObject();
+    }
+
+    public final void serializeWithType(final JsonGenerator jgen,
+        final SerializerProvider provider, final TypeSerializer typeSer)
+        throws IOException, JsonProcessingException
+    {
+        serialize(jgen, provider);
+    }
+
+    public final String toString()
+    {
+        return "op: " + op + "; path: \"" + path + "\"; value: " + value;
+    }
+}

src/main/resources/com/github/fge/jsonpatch/messages.properties

@@ -27,4 +27,5 @@ jsonPatch.noSuchIndex=no such index in target array
 jsonPatch.noSuchPath=no such path in target JSON document
 jsonPatch.parentNotContainer=parent of path to add to is not a container
 jsonPatch.valueTestFailure=value differs from expectations
+jsonPatch.invalidPolicy=invalid json operation policy
 mergePatch.notContainer=value is neither an object or an array (found %s)