Added KeyDeserializer class and test code (#1523)

* Solr w Apache SolrJ

* Solr w Apache SolrJ

* updated test names and moved add to @before method

* create apache-solrj module, moved code from spring-data-solr

* More examples for indexing,delete,and query for solrj

* More examples for indexing,delete,and query for solrj

* Jackson Map Serialize/Deserialize

* Jackson Map Serialize/Deserialize

* Jackson version update

* keydeserializer code added

* keydeserializer code added

jackson/src/main/java/com/baeldung/jackson/entities/ClassWithAMap.java

@@ -0,0 +1,24 @@
+package com.baeldung.jackson.entities;
+
+import java.util.Map;
+
+import com.baeldung.jackson.serialization.MyPairDeserializer;
+import com.fasterxml.jackson.annotation.JsonCreator;
+import com.fasterxml.jackson.annotation.JsonProperty;
+import com.fasterxml.jackson.databind.annotation.JsonDeserialize;
+
+public class ClassWithAMap {
+
+	@JsonProperty("map")
+	@JsonDeserialize(keyUsing = MyPairDeserializer.class)
+	private final Map<MyPair, String> map;
+
+	@JsonCreator
+	public ClassWithAMap(Map<MyPair, String> map) {
+		this.map = map;
+	}
+
+	public Map<MyPair, String> getMap() {
+		return map;
+	}
+}

jackson/src/main/java/com/baeldung/jackson/serialization/MyPairDeserializer.java

@@ -0,0 +1,18 @@
+package com.baeldung.jackson.serialization;
+
+import java.io.IOException;
+
+import com.baeldung.jackson.entities.MyPair;
+import com.fasterxml.jackson.core.JsonProcessingException;
+import com.fasterxml.jackson.databind.DeserializationContext;
+import com.fasterxml.jackson.databind.KeyDeserializer;
+
+public class MyPairDeserializer extends KeyDeserializer {
+
+	@Override
+	public MyPair deserializeKey(String key, DeserializationContext ctxt)
+			throws IOException, JsonProcessingException {
+
+		return new MyPair(key);
+	}
+}

jackson/src/test/java/com/baeldung/jackson/deserialization/JacksonMapDeserializeTest.java

@@ -7,6 +7,7 @@ import java.util.Map;
 import org.junit.Assert;
 import org.junit.Test;
 
+import com.baeldung.jackson.entities.ClassWithAMap;
 import com.baeldung.jackson.entities.MyPair;
 import com.fasterxml.jackson.core.JsonParseException;
 import com.fasterxml.jackson.core.type.TypeReference;
@@ -36,14 +37,21 @@ public class JacksonMapDeserializeTest {
 	public void whenObjectStringMapDeserialize_thenCorrect()
 			throws JsonParseException, JsonMappingException, IOException {
 
-		final String jsonInput = "{\"Abbott and Costello\" : \"Comedy\"}";
+		final String jsonInput = "{\"Abbott and Costello\":\"Comedy\"}";
 		final ObjectMapper mapper = new ObjectMapper();
 
 		TypeReference<HashMap<MyPair, String>> typeRef = new TypeReference<HashMap<MyPair, String>>() {
 		};
+
 		map = mapper.readValue(jsonInput, typeRef);
 
 		Assert.assertEquals("Comedy", map.get(new MyPair("Abbott", "Costello")));
+
+		ClassWithAMap classWithMap = mapper.readValue(jsonInput,
+				ClassWithAMap.class);
+
+		Assert.assertEquals("Comedy",
+				classWithMap.getMap().get(new MyPair("Abbott", "Costello")));
 	}
 
 	@Test